organizing GUImode-specific code

7 files changed, 2434 insertions, 0 deletions

diff --git a/src/gui/__init__.py b/src/gui/__init__.py
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/src/gui/__init__.py
diff --git a/src/gui/mainwindow.py b/src/gui/mainwindow.py
new file mode 100644
index 0000000..af6e190
--- /dev/null
+++ b/src/gui/mainwindow.py
@@ -0,0 +1,946 @@
+'''
+    When using GUI mode, this module's object (the main window) takes
+    user input to construct a program state (stored in the Core object).
+    This shows a preview of the video being created and allows for saving
+    projects and exporting the video at a later time.
+'''
+from PyQt5 import QtCore, QtGui, uic, QtWidgets
+from PyQt5.QtWidgets import QMenu, QShortcut
+from PIL import Image
+from queue import Queue
+import sys
+import os
+import signal
+import filecmp
+import time
+import logging
+
+from core import Core
+import preview_thread
+from preview_win import PreviewWindow
+from presetmanager import PresetManager
+from toolkit import disableWhenEncoding, disableWhenOpeningProject, checkOutput
+
+
+log = logging.getLogger('AVP.MainWindow')
+
+
+class MainWindow(QtWidgets.QMainWindow):
+    '''
+        The MainWindow wraps many Core methods in order to update the GUI
+        accordingly. E.g., instead of self.core.openProject(), it will use
+        self.openProject() and update the window titlebar within the wrapper.
+
+        MainWindow manages the autosave feature, although Core has the
+        primary functions for opening and creating project files.
+    '''
+
+    createVideo = QtCore.pyqtSignal()
+    newTask = QtCore.pyqtSignal(list)  # for the preview window
+    processTask = QtCore.pyqtSignal()
+
+    def __init__(self, window, project):
+        QtWidgets.QMainWindow.__init__(self)
+        self.window = window
+        self.core = Core()
+        log.debug(
+            'Main thread id: {}'.format(int(QtCore.QThread.currentThreadId())))
+
+        # widgets of component settings
+        self.pages = []
+        self.lastAutosave = time.time()
+        # list of previous five autosave times, used to reduce update spam
+        self.autosaveTimes = []
+        self.autosaveCooldown = 0.2
+        self.encoding = False
+
+        # Find settings created by Core object
+        self.dataDir = Core.dataDir
+        self.presetDir = Core.presetDir
+        self.autosavePath = os.path.join(self.dataDir, 'autosave.avp')
+        self.settings = Core.settings
+
+        self.presetManager = PresetManager(
+            uic.loadUi(
+                os.path.join(Core.wd, 'presetmanager.ui')), self)
+
+        # Create the preview window and its thread, queues, and timers
+        log.debug('Creating preview window')
+        self.previewWindow = PreviewWindow(self, os.path.join(
+            Core.wd, "background.png"))
+        window.verticalLayout_previewWrapper.addWidget(self.previewWindow)
+
+        log.debug('Starting preview thread')
+        self.previewQueue = Queue()
+        self.previewThread = QtCore.QThread(self)
+        self.previewWorker = preview_thread.Worker(self, self.previewQueue)
+        self.previewWorker.error.connect(self.previewWindow.threadError)
+        self.previewWorker.moveToThread(self.previewThread)
+        self.previewWorker.imageCreated.connect(self.showPreviewImage)
+        self.previewThread.start()
+
+        log.debug('Starting preview timer')
+        self.timer = QtCore.QTimer(self)
+        self.timer.timeout.connect(self.processTask.emit)
+        self.timer.start(500)
+
+        # Begin decorating the window and connecting events
+        self.window.installEventFilter(self)
+        componentList = self.window.listWidget_componentList
+
+        if sys.platform == 'darwin':
+            log.debug(
+                'Darwin detected: showing progress label below progress bar')
+            window.progressBar_createVideo.setTextVisible(False)
+        else:
+            window.progressLabel.setHidden(True)
+
+        window.toolButton_selectAudioFile.clicked.connect(
+            self.openInputFileDialog)
+
+        window.toolButton_selectOutputFile.clicked.connect(
+            self.openOutputFileDialog)
+
+        def changedField():
+            self.autosave()
+            self.updateWindowTitle()
+
+        window.lineEdit_audioFile.textChanged.connect(changedField)
+        window.lineEdit_outputFile.textChanged.connect(changedField)
+
+        window.progressBar_createVideo.setValue(0)
+
+        window.pushButton_createVideo.clicked.connect(
+            self.createAudioVisualisation)
+
+        window.pushButton_Cancel.clicked.connect(self.stopVideo)
+
+        for i, container in enumerate(Core.encoderOptions['containers']):
+            window.comboBox_videoContainer.addItem(container['name'])
+            if container['name'] == self.settings.value('outputContainer'):
+                selectedContainer = i
+
+        window.comboBox_videoContainer.setCurrentIndex(selectedContainer)
+        window.comboBox_videoContainer.currentIndexChanged.connect(
+            self.updateCodecs
+        )
+
+        self.updateCodecs()
+
+        for i in range(window.comboBox_videoCodec.count()):
+            codec = window.comboBox_videoCodec.itemText(i)
+            if codec == self.settings.value('outputVideoCodec'):
+                window.comboBox_videoCodec.setCurrentIndex(i)
+
+        for i in range(window.comboBox_audioCodec.count()):
+            codec = window.comboBox_audioCodec.itemText(i)
+            if codec == self.settings.value('outputAudioCodec'):
+                window.comboBox_audioCodec.setCurrentIndex(i)
+
+        window.comboBox_videoCodec.currentIndexChanged.connect(
+            self.updateCodecSettings
+        )
+
+        window.comboBox_audioCodec.currentIndexChanged.connect(
+            self.updateCodecSettings
+        )
+
+        vBitrate = int(self.settings.value('outputVideoBitrate'))
+        aBitrate = int(self.settings.value('outputAudioBitrate'))
+
+        window.spinBox_vBitrate.setValue(vBitrate)
+        window.spinBox_aBitrate.setValue(aBitrate)
+        window.spinBox_vBitrate.valueChanged.connect(self.updateCodecSettings)
+        window.spinBox_aBitrate.valueChanged.connect(self.updateCodecSettings)
+
+        # Make component buttons
+        self.compMenu = QMenu()
+        for i, comp in enumerate(self.core.modules):
+            action = self.compMenu.addAction(comp.Component.name)
+            action.triggered.connect(
+                lambda _, item=i: self.core.insertComponent(0, item, self)
+            )
+
+        self.window.pushButton_addComponent.setMenu(self.compMenu)
+
+        componentList.dropEvent = self.dragComponent
+        componentList.itemSelectionChanged.connect(
+            self.changeComponentWidget
+        )
+        componentList.itemSelectionChanged.connect(
+            self.presetManager.clearPresetListSelection
+        )
+        self.window.pushButton_removeComponent.clicked.connect(
+            lambda: self.removeComponent()
+        )
+
+        componentList.setContextMenuPolicy(QtCore.Qt.CustomContextMenu)
+        componentList.customContextMenuRequested.connect(
+            self.componentContextMenu
+        )
+
+        currentRes = str(self.settings.value('outputWidth'))+'x' + \
+            str(self.settings.value('outputHeight'))
+        for i, res in enumerate(Core.resolutions):
+            window.comboBox_resolution.addItem(res)
+            if res == currentRes:
+                currentRes = i
+                window.comboBox_resolution.setCurrentIndex(currentRes)
+                window.comboBox_resolution.currentIndexChanged.connect(
+                    self.updateResolution
+                )
+
+        self.window.pushButton_listMoveUp.clicked.connect(
+            lambda: self.moveComponent(-1)
+        )
+        self.window.pushButton_listMoveDown.clicked.connect(
+            lambda: self.moveComponent(1)
+        )
+
+        # Configure the Projects Menu
+        self.projectMenu = QMenu()
+        self.window.menuButton_newProject = self.projectMenu.addAction(
+            "New Project"
+        )
+        self.window.menuButton_newProject.triggered.connect(
+            lambda: self.createNewProject()
+        )
+        self.window.menuButton_openProject = self.projectMenu.addAction(
+            "Open Project"
+        )
+        self.window.menuButton_openProject.triggered.connect(
+            lambda: self.openOpenProjectDialog()
+        )
+
+        action = self.projectMenu.addAction("Save Project")
+        action.triggered.connect(self.saveCurrentProject)
+
+        action = self.projectMenu.addAction("Save Project As")
+        action.triggered.connect(self.openSaveProjectDialog)
+
+        self.window.pushButton_projects.setMenu(self.projectMenu)
+
+        # Configure the Presets Button
+        self.window.pushButton_presets.clicked.connect(
+            self.openPresetManager
+        )
+
+        self.updateWindowTitle()
+        log.debug('Showing main window')
+        window.show()
+
+        if project and project != self.autosavePath:
+            if not project.endswith('.avp'):
+                project += '.avp'
+            # open a project from the commandline
+            if not os.path.dirname(project):
+                project = os.path.join(
+                    self.settings.value("projectDir"), project
+                )
+            self.currentProject = project
+            self.settings.setValue("currentProject", project)
+            if os.path.exists(self.autosavePath):
+                os.remove(self.autosavePath)
+        else:
+            # open the last currentProject from settings
+            self.currentProject = self.settings.value("currentProject")
+
+            # delete autosave if it's identical to this project
+            if self.autosaveExists(identical=True):
+                os.remove(self.autosavePath)
+
+            if self.currentProject and os.path.exists(self.autosavePath):
+                ch = self.showMessage(
+                    msg="Restore unsaved changes in project '%s'?"
+                    % os.path.basename(self.currentProject)[:-4],
+                    showCancel=True)
+                if ch:
+                    self.saveProjectChanges()
+                else:
+                    os.remove(self.autosavePath)
+
+        self.openProject(self.currentProject, prompt=False)
+        self.drawPreview(True)
+
+        # verify Pillow version
+        if not self.settings.value("pilMsgShown") \
+                and 'post' not in Image.PILLOW_VERSION:
+            self.showMessage(
+                msg="You are using the standard version of the "
+                "Python imaging library (Pillow %s). Upgrade "
+                "to the Pillow-SIMD fork to enable hardware accelerations "
+                "and export videos faster." % Image.PILLOW_VERSION
+            )
+            self.settings.setValue("pilMsgShown", True)
+
+        # verify Ffmpeg version
+        if not self.settings.value("ffmpegMsgShown"):
+            try:
+                with open(os.devnull, "w") as f:
+                    ffmpegVers = checkOutput(
+                        ['ffmpeg', '-version'], stderr=f
+                    )
+                goodVersion = str(ffmpegVers).split()[2].startswith('3')
+            except Exception:
+                goodVersion = False
+        else:
+            goodVersion = True
+
+        if not goodVersion:
+            self.showMessage(
+                msg="You're using an old version of Ffmpeg. "
+                "Some features may not work as expected."
+            )
+        self.settings.setValue("ffmpegMsgShown", True)
+
+        # Hotkeys for projects
+        QtWidgets.QShortcut("Ctrl+S", self.window, self.saveCurrentProject)
+        QtWidgets.QShortcut("Ctrl+A", self.window, self.openSaveProjectDialog)
+        QtWidgets.QShortcut("Ctrl+O", self.window, self.openOpenProjectDialog)
+        QtWidgets.QShortcut("Ctrl+N", self.window, self.createNewProject)
+
+        # Hotkeys for component list
+        for inskey in ("Ctrl+T", QtCore.Qt.Key_Insert):
+            QtWidgets.QShortcut(
+                inskey, self.window,
+                activated=lambda: self.window.pushButton_addComponent.click()
+            )
+        for delkey in ("Ctrl+R", QtCore.Qt.Key_Delete):
+            QtWidgets.QShortcut(
+                delkey, self.window.listWidget_componentList,
+                self.removeComponent
+            )
+        QtWidgets.QShortcut(
+            "Ctrl+Space", self.window,
+            activated=lambda: self.window.listWidget_componentList.setFocus()
+        )
+        QtWidgets.QShortcut(
+            "Ctrl+Shift+S", self.window,
+            self.presetManager.openSavePresetDialog
+        )
+        QtWidgets.QShortcut(
+            "Ctrl+Shift+C", self.window, self.presetManager.clearPreset
+        )
+
+        QtWidgets.QShortcut(
+            "Ctrl+Up", self.window.listWidget_componentList,
+            activated=lambda: self.moveComponent(-1)
+        )
+        QtWidgets.QShortcut(
+            "Ctrl+Down", self.window.listWidget_componentList,
+            activated=lambda: self.moveComponent(1)
+        )
+        QtWidgets.QShortcut(
+            "Ctrl+Home", self.window.listWidget_componentList,
+            activated=lambda: self.moveComponent('top')
+        )
+        QtWidgets.QShortcut(
+            "Ctrl+End", self.window.listWidget_componentList,
+            activated=lambda: self.moveComponent('bottom')
+        )
+
+        # Debug Hotkeys
+        QtWidgets.QShortcut(
+            "Ctrl+Alt+Shift+R", self.window, self.drawPreview
+        )
+        QtWidgets.QShortcut(
+            "Ctrl+Alt+Shift+F", self.window, self.showFfmpegCommand
+        )
+
+    @QtCore.pyqtSlot()
+    def cleanUp(self, *args):
+        log.info('Ending the preview thread')
+        self.timer.stop()
+        self.previewThread.quit()
+        self.previewThread.wait()
+
+    @disableWhenOpeningProject
+    def updateWindowTitle(self):
+        appName = 'Audio Visualizer'
+        try:
+            if self.currentProject:
+                appName += ' - %s' % \
+                    os.path.splitext(
+                        os.path.basename(self.currentProject))[0]
+            if self.autosaveExists(identical=False):
+                appName += '*'
+        except AttributeError:
+            pass
+        log.debug('Setting window title to %s' % appName)
+        self.window.setWindowTitle(appName)
+
+    @QtCore.pyqtSlot(int, dict)
+    def updateComponentTitle(self, pos, presetStore=False):
+        if type(presetStore) is dict:
+            name = presetStore['preset']
+            if name is None or name not in self.core.savedPresets:
+                modified = False
+            else:
+                modified = (presetStore != self.core.savedPresets[name])
+        else:
+            modified = bool(presetStore)
+        if pos < 0:
+            pos = len(self.core.selectedComponents)-1
+        name = str(self.core.selectedComponents[pos])
+        title = str(name)
+        if self.core.selectedComponents[pos].currentPreset:
+            title += ' - %s' % self.core.selectedComponents[pos].currentPreset
+            if modified:
+                title += '*'
+        if type(presetStore) is bool:
+            log.debug('Forcing %s #%s\'s modified status to %s: %s' % (
+                name, pos, modified, title
+            ))
+        else:
+            log.debug('Setting %s #%s\'s title: %s' % (
+                name, pos, title
+            ))
+        self.window.listWidget_componentList.item(pos).setText(title)
+
+    def updateCodecs(self):
+        containerWidget = self.window.comboBox_videoContainer
+        vCodecWidget = self.window.comboBox_videoCodec
+        aCodecWidget = self.window.comboBox_audioCodec
+        index = containerWidget.currentIndex()
+        name = containerWidget.itemText(index)
+        self.settings.setValue('outputContainer', name)
+
+        vCodecWidget.clear()
+        aCodecWidget.clear()
+
+        for container in Core.encoderOptions['containers']:
+            if container['name'] == name:
+                for vCodec in container['video-codecs']:
+                    vCodecWidget.addItem(vCodec)
+                for aCodec in container['audio-codecs']:
+                    aCodecWidget.addItem(aCodec)
+
+    def updateCodecSettings(self):
+        '''Updates settings.ini to match encoder option widgets'''
+        vCodecWidget = self.window.comboBox_videoCodec
+        vBitrateWidget = self.window.spinBox_vBitrate
+        aBitrateWidget = self.window.spinBox_aBitrate
+        aCodecWidget = self.window.comboBox_audioCodec
+        currentVideoCodec = vCodecWidget.currentIndex()
+        currentVideoCodec = vCodecWidget.itemText(currentVideoCodec)
+        currentVideoBitrate = vBitrateWidget.value()
+        currentAudioCodec = aCodecWidget.currentIndex()
+        currentAudioCodec = aCodecWidget.itemText(currentAudioCodec)
+        currentAudioBitrate = aBitrateWidget.value()
+        self.settings.setValue('outputVideoCodec', currentVideoCodec)
+        self.settings.setValue('outputAudioCodec', currentAudioCodec)
+        self.settings.setValue('outputVideoBitrate', currentVideoBitrate)
+        self.settings.setValue('outputAudioBitrate', currentAudioBitrate)
+
+    @disableWhenOpeningProject
+    def autosave(self, force=False):
+        if not self.currentProject:
+            if os.path.exists(self.autosavePath):
+                os.remove(self.autosavePath)
+        elif force or time.time() - self.lastAutosave >= self.autosaveCooldown:
+            self.core.createProjectFile(self.autosavePath, self.window)
+            self.lastAutosave = time.time()
+            if len(self.autosaveTimes) >= 5:
+                # Do some math to reduce autosave spam. This gives a smooth
+                # curve up to 5 seconds cooldown and maintains that for 30 secs
+                # if a component is continuously updated
+                timeDiff = self.lastAutosave - self.autosaveTimes.pop()
+                if not force and timeDiff >= 1.0 \
+                        and timeDiff <= 10.0:
+                    if self.autosaveCooldown / 4.0 < 0.5:
+                        self.autosaveCooldown += 1.0
+                    self.autosaveCooldown = (
+                            5.0 * (self.autosaveCooldown / 5.0)
+                        ) + (self.autosaveCooldown / 5.0) * 2
+                elif force or timeDiff >= self.autosaveCooldown * 5:
+                    self.autosaveCooldown = 0.2
+            self.autosaveTimes.insert(0, self.lastAutosave)
+        else:
+            log.debug('Autosave rejected by cooldown')
+
+    def autosaveExists(self, identical=True):
+        '''Determines if creating the autosave should be blocked.'''
+        try:
+            if self.currentProject and os.path.exists(self.autosavePath) \
+                and filecmp.cmp(
+                    self.autosavePath, self.currentProject) == identical:
+                log.debug(
+                    'Autosave found %s to be identical'
+                    % 'not' if not identical else ''
+                )
+                return True
+        except FileNotFoundError:
+            log.error(
+                'Project file couldn\'t be located:', self.currentProject)
+            return identical
+        return False
+
+    def saveProjectChanges(self):
+        '''Overwrites project file with autosave file'''
+        try:
+            os.remove(self.currentProject)
+            os.rename(self.autosavePath, self.currentProject)
+            return True
+        except (FileNotFoundError, IsADirectoryError) as e:
+            self.showMessage(
+                msg='Project file couldn\'t be saved.',
+                detail=str(e))
+            return False
+
+    def openInputFileDialog(self):
+        inputDir = self.settings.value("inputDir", os.path.expanduser("~"))
+
+        fileName, _ = QtWidgets.QFileDialog.getOpenFileName(
+            self.window, "Open Audio File",
+            inputDir, "Audio Files (%s)" % " ".join(Core.audioFormats))
+
+        if fileName:
+            self.settings.setValue("inputDir", os.path.dirname(fileName))
+            self.window.lineEdit_audioFile.setText(fileName)
+
+    def openOutputFileDialog(self):
+        outputDir = self.settings.value("outputDir", os.path.expanduser("~"))
+
+        fileName, _ = QtWidgets.QFileDialog.getSaveFileName(
+            self.window, "Set Output Video File",
+            outputDir,
+            "Video Files (%s);; All Files (*)" % " ".join(
+                Core.videoFormats))
+
+        if fileName:
+            self.settings.setValue("outputDir", os.path.dirname(fileName))
+            self.window.lineEdit_outputFile.setText(fileName)
+
+    def stopVideo(self):
+        log.info('Export cancelled')
+        self.videoWorker.cancel()
+        self.canceled = True
+
+    def createAudioVisualisation(self):
+        # create output video if mandatory settings are filled in
+        audioFile = self.window.lineEdit_audioFile.text()
+        outputPath = self.window.lineEdit_outputFile.text()
+
+        if audioFile and outputPath and self.core.selectedComponents:
+            if not os.path.dirname(outputPath):
+                outputPath = os.path.join(
+                    os.path.expanduser("~"), outputPath)
+            if outputPath and os.path.isdir(outputPath):
+                self.showMessage(
+                    msg='Chosen filename matches a directory, which '
+                        'cannot be overwritten. Please choose a different '
+                        'filename or move the directory.',
+                    icon='Warning',
+                )
+                return
+        else:
+            if not audioFile or not outputPath:
+                self.showMessage(
+                    msg="You must select an audio file and output filename."
+                )
+            elif not self.core.selectedComponents:
+                self.showMessage(
+                    msg="Not enough components."
+                )
+            return
+
+        self.canceled = False
+        self.progressBarUpdated(-1)
+        self.videoWorker = self.core.newVideoWorker(
+            self, audioFile, outputPath
+        )
+        self.videoWorker.progressBarUpdate.connect(self.progressBarUpdated)
+        self.videoWorker.progressBarSetText.connect(
+            self.progressBarSetText)
+        self.videoWorker.imageCreated.connect(self.showPreviewImage)
+        self.videoWorker.encoding.connect(self.changeEncodingStatus)
+        self.createVideo.emit()
+
+    @QtCore.pyqtSlot(str, str)
+    def videoThreadError(self, msg, detail):
+        try:
+            self.stopVideo()
+        except AttributeError as e:
+            if 'videoWorker' not in str(e):
+                raise
+        self.showMessage(
+            msg=msg,
+            detail=detail,
+            icon='Critical',
+        )
+
+    def changeEncodingStatus(self, status):
+        self.encoding = status
+        if status:
+            self.window.pushButton_createVideo.setEnabled(False)
+            self.window.pushButton_Cancel.setEnabled(True)
+            self.window.comboBox_resolution.setEnabled(False)
+            self.window.stackedWidget.setEnabled(False)
+            self.window.tab_encoderSettings.setEnabled(False)
+            self.window.label_audioFile.setEnabled(False)
+            self.window.toolButton_selectAudioFile.setEnabled(False)
+            self.window.label_outputFile.setEnabled(False)
+            self.window.toolButton_selectOutputFile.setEnabled(False)
+            self.window.lineEdit_audioFile.setEnabled(False)
+            self.window.lineEdit_outputFile.setEnabled(False)
+            self.window.pushButton_addComponent.setEnabled(False)
+            self.window.pushButton_removeComponent.setEnabled(False)
+            self.window.pushButton_listMoveDown.setEnabled(False)
+            self.window.pushButton_listMoveUp.setEnabled(False)
+            self.window.menuButton_newProject.setEnabled(False)
+            self.window.menuButton_openProject.setEnabled(False)
+            if sys.platform == 'darwin':
+                self.window.progressLabel.setHidden(False)
+            else:
+                self.window.listWidget_componentList.setEnabled(False)
+        else:
+            self.window.pushButton_createVideo.setEnabled(True)
+            self.window.pushButton_Cancel.setEnabled(False)
+            self.window.comboBox_resolution.setEnabled(True)
+            self.window.stackedWidget.setEnabled(True)
+            self.window.tab_encoderSettings.setEnabled(True)
+            self.window.label_audioFile.setEnabled(True)
+            self.window.toolButton_selectAudioFile.setEnabled(True)
+            self.window.lineEdit_audioFile.setEnabled(True)
+            self.window.label_outputFile.setEnabled(True)
+            self.window.toolButton_selectOutputFile.setEnabled(True)
+            self.window.lineEdit_outputFile.setEnabled(True)
+            self.window.pushButton_addComponent.setEnabled(True)
+            self.window.pushButton_removeComponent.setEnabled(True)
+            self.window.pushButton_listMoveDown.setEnabled(True)
+            self.window.pushButton_listMoveUp.setEnabled(True)
+            self.window.menuButton_newProject.setEnabled(True)
+            self.window.menuButton_openProject.setEnabled(True)
+            self.window.listWidget_componentList.setEnabled(True)
+            self.window.progressLabel.setHidden(True)
+            self.drawPreview(True)
+
+    @QtCore.pyqtSlot(int)
+    def progressBarUpdated(self, value):
+        self.window.progressBar_createVideo.setValue(value)
+
+    @QtCore.pyqtSlot(str)
+    def progressBarSetText(self, value):
+        if sys.platform == 'darwin':
+            self.window.progressLabel.setText(value)
+        else:
+            self.window.progressBar_createVideo.setFormat(value)
+
+    def updateResolution(self):
+        resIndex = int(self.window.comboBox_resolution.currentIndex())
+        res = Core.resolutions[resIndex].split('x')
+        changed = res[0] != self.settings.value("outputWidth")
+        self.settings.setValue('outputWidth', res[0])
+        self.settings.setValue('outputHeight', res[1])
+        if changed:
+            for i in range(len(self.core.selectedComponents)):
+                self.core.updateComponent(i)
+
+    def drawPreview(self, force=False, **kwargs):
+        '''Use autosave keyword arg to force saving or not saving if needed'''
+        self.newTask.emit(self.core.selectedComponents)
+        # self.processTask.emit()
+        if force or 'autosave' in kwargs:
+            if force or kwargs['autosave']:
+                self.autosave(True)
+        else:
+            self.autosave()
+        self.updateWindowTitle()
+
+    @QtCore.pyqtSlot(QtGui.QImage)
+    def showPreviewImage(self, image):
+        self.previewWindow.changePixmap(image)
+
+    def showFfmpegCommand(self):
+        from textwrap import wrap
+        from toolkit.ffmpeg import createFfmpegCommand
+        command = createFfmpegCommand(
+            self.window.lineEdit_audioFile.text(),
+            self.window.lineEdit_outputFile.text(),
+            self.core.selectedComponents
+        )
+        lines = wrap(" ".join(command), 49)
+        self.showMessage(
+            msg="Current FFmpeg command:\n\n %s" % " ".join(lines)
+        )
+
+    def insertComponent(self, index):
+        componentList = self.window.listWidget_componentList
+        stackedWidget = self.window.stackedWidget
+
+        componentList.insertItem(
+            index,
+            self.core.selectedComponents[index].name)
+        componentList.setCurrentRow(index)
+
+        # connect to signal that adds an asterisk when modified
+        self.core.selectedComponents[index].modified.connect(
+            self.updateComponentTitle)
+
+        self.pages.insert(index, self.core.selectedComponents[index].page)
+        stackedWidget.insertWidget(index, self.pages[index])
+        stackedWidget.setCurrentIndex(index)
+
+        return index
+
+    def removeComponent(self):
+        componentList = self.window.listWidget_componentList
+
+        for selected in componentList.selectedItems():
+            index = componentList.row(selected)
+            self.window.stackedWidget.removeWidget(self.pages[index])
+            componentList.takeItem(index)
+            self.core.removeComponent(index)
+            self.pages.pop(index)
+            self.changeComponentWidget()
+        self.drawPreview()
+
+    @disableWhenEncoding
+    def moveComponent(self, change):
+        '''Moves a component relatively from its current position'''
+        componentList = self.window.listWidget_componentList
+        if change == 'top':
+            change = -componentList.currentRow()
+        elif change == 'bottom':
+            change = len(componentList)-componentList.currentRow()-1
+        stackedWidget = self.window.stackedWidget
+
+        row = componentList.currentRow()
+        newRow = row + change
+        if newRow > -1 and newRow < componentList.count():
+            self.core.moveComponent(row, newRow)
+
+            # update widgets
+            page = self.pages.pop(row)
+            self.pages.insert(newRow, page)
+            item = componentList.takeItem(row)
+            newItem = componentList.insertItem(newRow, item)
+            widget = stackedWidget.removeWidget(page)
+            stackedWidget.insertWidget(newRow, page)
+            componentList.setCurrentRow(newRow)
+            stackedWidget.setCurrentIndex(newRow)
+            self.drawPreview(True)
+
+    def getComponentListMousePos(self, position):
+        '''
+        Given a QPos, returns the component index under the mouse cursor
+        or -1 if no component is there.
+        '''
+        componentList = self.window.listWidget_componentList
+
+        modelIndexes = [
+            componentList.model().index(i)
+            for i in range(componentList.count())
+        ]
+        rects = [
+            componentList.visualRect(modelIndex)
+            for modelIndex in modelIndexes
+        ]
+        mousePos = [rect.contains(position) for rect in rects]
+        if not any(mousePos):
+            # Not clicking a component
+            mousePos = -1
+        else:
+            mousePos = mousePos.index(True)
+        log.debug('Click component list row %s' % mousePos)
+        return mousePos
+
+    @disableWhenEncoding
+    def dragComponent(self, event):
+        '''Used as Qt drop event for the component listwidget'''
+        componentList = self.window.listWidget_componentList
+        mousePos = self.getComponentListMousePos(event.pos())
+        if mousePos > -1:
+            change = (componentList.currentRow() - mousePos) * -1
+        else:
+            change = (componentList.count() - componentList.currentRow() - 1)
+        self.moveComponent(change)
+
+    def changeComponentWidget(self):
+        selected = self.window.listWidget_componentList.selectedItems()
+        if selected:
+            index = self.window.listWidget_componentList.row(selected[0])
+            self.window.stackedWidget.setCurrentIndex(index)
+
+    def openPresetManager(self):
+        '''Preset manager for importing, exporting, renaming, deleting'''
+        self.presetManager.show()
+
+    def clear(self):
+        '''Get a blank slate'''
+        self.core.clearComponents()
+        self.window.listWidget_componentList.clear()
+        for widget in self.pages:
+            self.window.stackedWidget.removeWidget(widget)
+        self.pages = []
+        for field in (
+                self.window.lineEdit_audioFile,
+                self.window.lineEdit_outputFile
+                ):
+            field.blockSignals(True)
+            field.setText('')
+            field.blockSignals(False)
+        self.progressBarUpdated(0)
+        self.progressBarSetText('')
+
+    @disableWhenEncoding
+    def createNewProject(self, prompt=True):
+        if prompt:
+            self.openSaveChangesDialog('starting a new project')
+
+        self.clear()
+        self.currentProject = None
+        self.settings.setValue("currentProject", None)
+        self.drawPreview(True)
+
+    def saveCurrentProject(self):
+        if self.currentProject:
+            self.core.createProjectFile(self.currentProject, self.window)
+            try:
+                os.remove(self.autosavePath)
+            except FileNotFoundError:
+                pass
+            self.updateWindowTitle()
+        else:
+            self.openSaveProjectDialog()
+
+    def openSaveChangesDialog(self, phrase):
+        success = True
+        if self.autosaveExists(identical=False):
+            ch = self.showMessage(
+                msg="You have unsaved changes in project '%s'. "
+                "Save before %s?" % (
+                    os.path.basename(self.currentProject)[:-4],
+                    phrase
+                ),
+                showCancel=True)
+            if ch:
+                success = self.saveProjectChanges()
+
+        if success and os.path.exists(self.autosavePath):
+            os.remove(self.autosavePath)
+
+    def openSaveProjectDialog(self):
+        filename, _ = QtWidgets.QFileDialog.getSaveFileName(
+            self.window, "Create Project File",
+            self.settings.value("projectDir"),
+            "Project Files (*.avp)")
+        if not filename:
+            return
+        if not filename.endswith(".avp"):
+            filename += '.avp'
+        self.settings.setValue("projectDir", os.path.dirname(filename))
+        self.settings.setValue("currentProject", filename)
+        self.currentProject = filename
+        self.core.createProjectFile(filename, self.window)
+        self.updateWindowTitle()
+
+    @disableWhenEncoding
+    def openOpenProjectDialog(self):
+        filename, _ = QtWidgets.QFileDialog.getOpenFileName(
+            self.window, "Open Project File",
+            self.settings.value("projectDir"),
+            "Project Files (*.avp)")
+        self.openProject(filename)
+
+    def openProject(self, filepath, prompt=True):
+        if not filepath or not os.path.exists(filepath) \
+          or not filepath.endswith('.avp'):
+            return
+
+        self.clear()
+        # ask to save any changes that are about to get deleted
+        if prompt:
+            self.openSaveChangesDialog('opening another project')
+
+        self.currentProject = filepath
+        self.settings.setValue("currentProject", filepath)
+        self.settings.setValue("projectDir", os.path.dirname(filepath))
+        # actually load the project using core method
+        self.core.openProject(self, filepath)
+        self.drawPreview(autosave=False)
+        self.updateWindowTitle()
+
+    def showMessage(self, **kwargs):
+        parent = kwargs['parent'] if 'parent' in kwargs else self.window
+        msg = QtWidgets.QMessageBox(parent)
+        msg.setModal(True)
+        msg.setText(kwargs['msg'])
+        msg.setIcon(
+            eval('QtWidgets.QMessageBox.%s' % kwargs['icon'])
+            if 'icon' in kwargs else QtWidgets.QMessageBox.Information
+        )
+        msg.setDetailedText(kwargs['detail'] if 'detail' in kwargs else None)
+        if 'showCancel'in kwargs and kwargs['showCancel']:
+            msg.setStandardButtons(
+                QtWidgets.QMessageBox.Ok | QtWidgets.QMessageBox.Cancel)
+        else:
+            msg.setStandardButtons(QtWidgets.QMessageBox.Ok)
+        ch = msg.exec_()
+        if ch == 1024:
+            return True
+        return False
+
+    @disableWhenEncoding
+    def componentContextMenu(self, QPos):
+        '''Appears when right-clicking the component list'''
+        componentList = self.window.listWidget_componentList
+        self.menu = QMenu()
+        parentPosition = componentList.mapToGlobal(QtCore.QPoint(0, 0))
+
+        index = self.getComponentListMousePos(QPos)
+        if index > -1:
+            # Show preset menu if clicking a component
+            self.presetManager.findPresets()
+            menuItem = self.menu.addAction("Save Preset")
+            menuItem.triggered.connect(
+                self.presetManager.openSavePresetDialog
+            )
+
+            # submenu for opening presets
+            try:
+                presets = self.presetManager.presets[
+                    str(self.core.selectedComponents[index])
+                ]
+                self.presetSubmenu = QMenu("Open Preset")
+                self.menu.addMenu(self.presetSubmenu)
+
+                for version, presetName in presets:
+                    menuItem = self.presetSubmenu.addAction(presetName)
+                    menuItem.triggered.connect(
+                        lambda _, presetName=presetName:
+                            self.presetManager.openPreset(presetName)
+                    )
+            except KeyError:
+                pass
+
+            if self.core.selectedComponents[index].currentPreset:
+                menuItem = self.menu.addAction("Clear Preset")
+                menuItem.triggered.connect(
+                    self.presetManager.clearPreset
+                )
+            self.menu.addSeparator()
+
+        # "Add Component" submenu
+        self.submenu = QMenu("Add")
+        self.menu.addMenu(self.submenu)
+        insertCompAtTop = self.settings.value("pref_insertCompAtTop")
+        for i, comp in enumerate(self.core.modules):
+            menuItem = self.submenu.addAction(comp.Component.name)
+            menuItem.triggered.connect(
+                lambda _, item=i: self.core.insertComponent(
+                    0 if insertCompAtTop else index, item, self
+                )
+            )
+
+        self.menu.move(parentPosition + QPos)
+        self.menu.show()
+
+    def eventFilter(self, object, event):
+        if event.type() == QtCore.QEvent.WindowActivate \
+                or event.type() == QtCore.QEvent.FocusIn:
+            Core.windowHasFocus = True
+        elif event.type() == QtCore.QEvent.WindowDeactivate \
+                or event.type() == QtCore.QEvent.FocusOut:
+                    Core.windowHasFocus = False
+        return False
diff --git a/src/gui/mainwindow.ui b/src/gui/mainwindow.ui
new file mode 100644
index 0000000..b43d375
--- /dev/null
+++ b/src/gui/mainwindow.ui
@@ -0,0 +1,828 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>MainWindow</class>
+ <widget class="QMainWindow" name="MainWindow">
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>1008</width>
+    <height>575</height>
+   </rect>
+  </property>
+  <property name="sizePolicy">
+   <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+    <horstretch>0</horstretch>
+    <verstretch>0</verstretch>
+   </sizepolicy>
+  </property>
+  <property name="minimumSize">
+   <size>
+    <width>0</width>
+    <height>0</height>
+   </size>
+  </property>
+  <property name="focusPolicy">
+   <enum>Qt::StrongFocus</enum>
+  </property>
+  <property name="windowTitle">
+   <string>MainWindow</string>
+  </property>
+  <widget class="QWidget" name="centralwidget">
+   <property name="sizePolicy">
+    <sizepolicy hsizetype="Preferred" vsizetype="Preferred">
+     <horstretch>0</horstretch>
+     <verstretch>0</verstretch>
+    </sizepolicy>
+   </property>
+   <property name="autoFillBackground">
+    <bool>false</bool>
+   </property>
+   <layout class="QVBoxLayout" name="verticalLayout">
+    <property name="leftMargin">
+     <number>9</number>
+    </property>
+    <property name="bottomMargin">
+     <number>0</number>
+    </property>
+    <item>
+     <layout class="QHBoxLayout" name="horizontalLayout">
+      <item>
+       <spacer name="verticalSpacer_2">
+        <property name="orientation">
+         <enum>Qt::Vertical</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::MinimumExpanding</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>0</width>
+          <height>360</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item>
+       <layout class="QVBoxLayout" name="verticalLayout_previewWrapper">
+        <property name="sizeConstraint">
+         <enum>QLayout::SetDefaultConstraint</enum>
+        </property>
+        <property name="topMargin">
+         <number>0</number>
+        </property>
+        <item>
+         <spacer name="horizontalSpacer_previewSpacer">
+          <property name="orientation">
+           <enum>Qt::Horizontal</enum>
+          </property>
+          <property name="sizeType">
+           <enum>QSizePolicy::MinimumExpanding</enum>
+          </property>
+          <property name="sizeHint" stdset="0">
+           <size>
+            <width>420</width>
+            <height>0</height>
+           </size>
+          </property>
+         </spacer>
+        </item>
+       </layout>
+      </item>
+      <item>
+       <layout class="QVBoxLayout" name="verticalLayout_3">
+        <property name="sizeConstraint">
+         <enum>QLayout::SetMinimumSize</enum>
+        </property>
+        <property name="leftMargin">
+         <number>3</number>
+        </property>
+        <item>
+         <layout class="QVBoxLayout" name="verticalLayout_4">
+          <property name="sizeConstraint">
+           <enum>QLayout::SetMinimumSize</enum>
+          </property>
+          <property name="leftMargin">
+           <number>3</number>
+          </property>
+          <item>
+           <layout class="QHBoxLayout" name="horizontalLayout_16">
+            <property name="sizeConstraint">
+             <enum>QLayout::SetMinimumSize</enum>
+            </property>
+            <item>
+             <spacer name="horizontalSpacer_6">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeType">
+               <enum>QSizePolicy::Fixed</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>140</width>
+                <height>20</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <widget class="QPushButton" name="pushButton_projects">
+              <property name="text">
+               <string>Projects</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="pushButton_presets">
+              <property name="text">
+               <string>Presets</string>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+          <item>
+           <spacer name="verticalSpacer">
+            <property name="orientation">
+             <enum>Qt::Horizontal</enum>
+            </property>
+            <property name="sizeType">
+             <enum>QSizePolicy::Minimum</enum>
+            </property>
+            <property name="sizeHint" stdset="0">
+             <size>
+              <width>20</width>
+              <height>2</height>
+             </size>
+            </property>
+           </spacer>
+          </item>
+          <item>
+           <widget class="QListWidget" name="listWidget_componentList">
+            <property name="sizePolicy">
+             <sizepolicy hsizetype="Minimum" vsizetype="Expanding">
+              <horstretch>0</horstretch>
+              <verstretch>0</verstretch>
+             </sizepolicy>
+            </property>
+            <property name="minimumSize">
+             <size>
+              <width>0</width>
+              <height>0</height>
+             </size>
+            </property>
+            <property name="maximumSize">
+             <size>
+              <width>16777215</width>
+              <height>16777215</height>
+             </size>
+            </property>
+            <property name="acceptDrops">
+             <bool>true</bool>
+            </property>
+            <property name="frameShape">
+             <enum>QFrame::StyledPanel</enum>
+            </property>
+            <property name="frameShadow">
+             <enum>QFrame::Sunken</enum>
+            </property>
+            <property name="lineWidth">
+             <number>1</number>
+            </property>
+            <property name="tabKeyNavigation">
+             <bool>true</bool>
+            </property>
+            <property name="dragEnabled">
+             <bool>true</bool>
+            </property>
+            <property name="dragDropOverwriteMode">
+             <bool>false</bool>
+            </property>
+            <property name="dragDropMode">
+             <enum>QAbstractItemView::InternalMove</enum>
+            </property>
+            <property name="defaultDropAction">
+             <enum>Qt::MoveAction</enum>
+            </property>
+           </widget>
+          </item>
+          <item>
+           <layout class="QHBoxLayout" name="horizontalLayout_14">
+            <item>
+             <widget class="QPushButton" name="pushButton_addComponent">
+              <property name="text">
+               <string>Add</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="pushButton_removeComponent">
+              <property name="text">
+               <string>Remove</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="pushButton_listMoveUp">
+              <property name="text">
+               <string>Up</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="pushButton_listMoveDown">
+              <property name="text">
+               <string>Down</string>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+         </layout>
+        </item>
+        <item>
+         <layout class="QHBoxLayout" name="horizontalLayout_7">
+          <property name="leftMargin">
+           <number>4</number>
+          </property>
+          <property name="rightMargin">
+           <number>2</number>
+          </property>
+         </layout>
+        </item>
+       </layout>
+      </item>
+     </layout>
+    </item>
+    <item>
+     <layout class="QHBoxLayout" name="horizontalLayout_2">
+      <property name="sizeConstraint">
+       <enum>QLayout::SetFixedSize</enum>
+      </property>
+      <property name="topMargin">
+       <number>4</number>
+      </property>
+      <property name="rightMargin">
+       <number>0</number>
+      </property>
+      <item>
+       <widget class="QTabWidget" name="tabWidget">
+        <property name="sizePolicy">
+         <sizepolicy hsizetype="MinimumExpanding" vsizetype="Fixed">
+          <horstretch>0</horstretch>
+          <verstretch>0</verstretch>
+         </sizepolicy>
+        </property>
+        <property name="minimumSize">
+         <size>
+          <width>500</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="maximumSize">
+         <size>
+          <width>16777215</width>
+          <height>180</height>
+         </size>
+        </property>
+        <property name="tabPosition">
+         <enum>QTabWidget::North</enum>
+        </property>
+        <property name="tabShape">
+         <enum>QTabWidget::Rounded</enum>
+        </property>
+        <property name="currentIndex">
+         <number>0</number>
+        </property>
+        <widget class="QWidget" name="tab_exportVideo">
+         <attribute name="title">
+          <string>Export Video</string>
+         </attribute>
+         <layout class="QVBoxLayout" name="verticalLayout_10">
+          <property name="margin">
+           <number>10</number>
+          </property>
+          <item>
+           <layout class="QHBoxLayout" name="horizontalLayout_4">
+            <property name="topMargin">
+             <number>0</number>
+            </property>
+            <item>
+             <widget class="QLabel" name="label_audioFile">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="minimumSize">
+               <size>
+                <width>85</width>
+                <height>0</height>
+               </size>
+              </property>
+              <property name="maximumSize">
+               <size>
+                <width>80</width>
+                <height>16777215</height>
+               </size>
+              </property>
+              <property name="baseSize">
+               <size>
+                <width>80</width>
+                <height>0</height>
+               </size>
+              </property>
+              <property name="text">
+               <string>Audio File</string>
+              </property>
+              <property name="alignment">
+               <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignVCenter</set>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QLineEdit" name="lineEdit_audioFile">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="MinimumExpanding" vsizetype="Fixed">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="minimumSize">
+               <size>
+                <width>0</width>
+                <height>28</height>
+               </size>
+              </property>
+              <property name="maximumSize">
+               <size>
+                <width>16777215</width>
+                <height>28</height>
+               </size>
+              </property>
+              <property name="baseSize">
+               <size>
+                <width>0</width>
+                <height>0</height>
+               </size>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QToolButton" name="toolButton_selectAudioFile">
+              <property name="minimumSize">
+               <size>
+                <width>0</width>
+                <height>28</height>
+               </size>
+              </property>
+              <property name="maximumSize">
+               <size>
+                <width>16777215</width>
+                <height>28</height>
+               </size>
+              </property>
+              <property name="text">
+               <string>...</string>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+          <item>
+           <layout class="QVBoxLayout" name="verticalLayout_11">
+            <item>
+             <layout class="QHBoxLayout" name="horizontalLayout_6">
+              <item>
+               <widget class="QLabel" name="label_outputFile">
+                <property name="sizePolicy">
+                 <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                  <horstretch>0</horstretch>
+                  <verstretch>0</verstretch>
+                 </sizepolicy>
+                </property>
+                <property name="minimumSize">
+                 <size>
+                  <width>85</width>
+                  <height>0</height>
+                 </size>
+                </property>
+                <property name="baseSize">
+                 <size>
+                  <width>0</width>
+                  <height>0</height>
+                 </size>
+                </property>
+                <property name="text">
+                 <string>Output File</string>
+                </property>
+                <property name="alignment">
+                 <set>Qt::AlignLeading|Qt::AlignLeft|Qt::AlignVCenter</set>
+                </property>
+               </widget>
+              </item>
+              <item>
+               <widget class="QLineEdit" name="lineEdit_outputFile">
+                <property name="sizePolicy">
+                 <sizepolicy hsizetype="Minimum" vsizetype="Fixed">
+                  <horstretch>0</horstretch>
+                  <verstretch>0</verstretch>
+                 </sizepolicy>
+                </property>
+                <property name="minimumSize">
+                 <size>
+                  <width>0</width>
+                  <height>28</height>
+                 </size>
+                </property>
+                <property name="maximumSize">
+                 <size>
+                  <width>16777215</width>
+                  <height>28</height>
+                 </size>
+                </property>
+               </widget>
+              </item>
+              <item>
+               <widget class="QToolButton" name="toolButton_selectOutputFile">
+                <property name="minimumSize">
+                 <size>
+                  <width>0</width>
+                  <height>28</height>
+                 </size>
+                </property>
+                <property name="maximumSize">
+                 <size>
+                  <width>16777215</width>
+                  <height>28</height>
+                 </size>
+                </property>
+                <property name="text">
+                 <string>...</string>
+                </property>
+               </widget>
+              </item>
+             </layout>
+            </item>
+           </layout>
+          </item>
+          <item>
+           <layout class="QHBoxLayout" name="horizontalLayout_3">
+            <property name="margin">
+             <number>0</number>
+            </property>
+            <item>
+             <widget class="QProgressBar" name="progressBar_createVideo">
+              <property name="minimumSize">
+               <size>
+                <width>0</width>
+                <height>0</height>
+               </size>
+              </property>
+              <property name="value">
+               <number>24</number>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="horizontalSpacer">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeType">
+               <enum>QSizePolicy::Minimum</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>10</width>
+                <height>20</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <widget class="QPushButton" name="pushButton_createVideo">
+              <property name="text">
+               <string>Create Video</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QPushButton" name="pushButton_Cancel">
+              <property name="enabled">
+               <bool>false</bool>
+              </property>
+              <property name="text">
+               <string>Cancel</string>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+          <item>
+           <widget class="QLabel" name="progressLabel">
+            <property name="text">
+             <string/>
+            </property>
+            <property name="scaledContents">
+             <bool>true</bool>
+            </property>
+            <property name="alignment">
+             <set>Qt::AlignCenter</set>
+            </property>
+            <property name="indent">
+             <number>-1</number>
+            </property>
+           </widget>
+          </item>
+         </layout>
+         <zorder></zorder>
+         <zorder></zorder>
+         <zorder>progressLabel</zorder>
+        </widget>
+        <widget class="QWidget" name="tab_encoderSettings">
+         <attribute name="title">
+          <string>Encoder Settings</string>
+         </attribute>
+         <layout class="QVBoxLayout" name="verticalLayout_9">
+          <property name="margin">
+           <number>10</number>
+          </property>
+          <item>
+           <layout class="QHBoxLayout" name="horizontalLayout_13">
+            <item>
+             <widget class="QLabel" name="label_videoFormat">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="minimumSize">
+               <size>
+                <width>85</width>
+                <height>0</height>
+               </size>
+              </property>
+              <property name="text">
+               <string>Container</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QComboBox" name="comboBox_videoContainer">
+              <property name="minimumSize">
+               <size>
+                <width>150</width>
+                <height>0</height>
+               </size>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="horizontalSpacer_5">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeType">
+               <enum>QSizePolicy::Minimum</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>5</width>
+                <height>5</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <widget class="QLabel" name="label_videoPreset">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="text">
+               <string>Resolution</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QComboBox" name="comboBox_resolution">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="minimumSize">
+               <size>
+                <width>0</width>
+                <height>0</height>
+               </size>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+          <item>
+           <layout class="QHBoxLayout" name="horizontalLayout_10">
+            <item>
+             <widget class="QLabel" name="label_videoCodec">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="minimumSize">
+               <size>
+                <width>85</width>
+                <height>0</height>
+               </size>
+              </property>
+              <property name="text">
+               <string>Video Codec</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QComboBox" name="comboBox_videoCodec">
+              <property name="minimumSize">
+               <size>
+                <width>150</width>
+                <height>0</height>
+               </size>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="horizontalSpacer_4">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeType">
+               <enum>QSizePolicy::Fixed</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>5</width>
+                <height>5</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <widget class="QLabel" name="label_resolution">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="text">
+               <string>Video Bitrate (Kbps)</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QSpinBox" name="spinBox_vBitrate">
+              <property name="maximum">
+               <number>99999</number>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+          <item>
+           <layout class="QHBoxLayout" name="horizontalLayout_11">
+            <item>
+             <widget class="QLabel" name="label_audioCodec">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="minimumSize">
+               <size>
+                <width>85</width>
+                <height>0</height>
+               </size>
+              </property>
+              <property name="text">
+               <string>Audio Codec</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QComboBox" name="comboBox_audioCodec">
+              <property name="minimumSize">
+               <size>
+                <width>150</width>
+                <height>0</height>
+               </size>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <spacer name="horizontalSpacer_3">
+              <property name="orientation">
+               <enum>Qt::Horizontal</enum>
+              </property>
+              <property name="sizeType">
+               <enum>QSizePolicy::Fixed</enum>
+              </property>
+              <property name="sizeHint" stdset="0">
+               <size>
+                <width>5</width>
+                <height>10</height>
+               </size>
+              </property>
+             </spacer>
+            </item>
+            <item>
+             <widget class="QLabel" name="label_audioBitrate">
+              <property name="sizePolicy">
+               <sizepolicy hsizetype="Fixed" vsizetype="Preferred">
+                <horstretch>0</horstretch>
+                <verstretch>0</verstretch>
+               </sizepolicy>
+              </property>
+              <property name="text">
+               <string>Audio Bitrate (Kbps)</string>
+              </property>
+             </widget>
+            </item>
+            <item>
+             <widget class="QSpinBox" name="spinBox_aBitrate">
+              <property name="maximum">
+               <number>9999</number>
+              </property>
+             </widget>
+            </item>
+           </layout>
+          </item>
+         </layout>
+        </widget>
+       </widget>
+      </item>
+      <item>
+       <layout class="QVBoxLayout" name="verticalLayout_5">
+        <property name="sizeConstraint">
+         <enum>QLayout::SetDefaultConstraint</enum>
+        </property>
+        <item>
+         <spacer name="horizontalSpacer_2">
+          <property name="orientation">
+           <enum>Qt::Horizontal</enum>
+          </property>
+          <property name="sizeType">
+           <enum>QSizePolicy::MinimumExpanding</enum>
+          </property>
+          <property name="sizeHint" stdset="0">
+           <size>
+            <width>500</width>
+            <height>0</height>
+           </size>
+          </property>
+         </spacer>
+        </item>
+        <item>
+         <widget class="QStackedWidget" name="stackedWidget">
+          <property name="sizePolicy">
+           <sizepolicy hsizetype="Expanding" vsizetype="Fixed">
+            <horstretch>0</horstretch>
+            <verstretch>0</verstretch>
+           </sizepolicy>
+          </property>
+          <property name="minimumSize">
+           <size>
+            <width>0</width>
+            <height>180</height>
+           </size>
+          </property>
+          <property name="maximumSize">
+           <size>
+            <width>16777215</width>
+            <height>180</height>
+           </size>
+          </property>
+          <property name="currentIndex">
+           <number>-1</number>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
+     </layout>
+    </item>
+   </layout>
+  </widget>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/gui/presetmanager.py b/src/gui/presetmanager.py
new file mode 100644
index 0000000..b1eeb34
--- /dev/null
+++ b/src/gui/presetmanager.py
@@ -0,0 +1,358 @@
+'''
+    Preset manager object handles all interactions with presets, including
+    the context menu accessed from MainWindow.
+'''
+from PyQt5 import QtCore, QtWidgets
+import string
+import os
+
+from toolkit import badName
+from core import Core
+
+
+class PresetManager(QtWidgets.QDialog):
+    def __init__(self, window, parent):
+        super().__init__(parent.window)
+        self.parent = parent
+        self.core = parent.core
+        self.settings = parent.settings
+        self.presetDir = parent.presetDir
+        if not self.settings.value('presetDir'):
+            self.settings.setValue(
+                "presetDir",
+                os.path.join(parent.dataDir, 'projects'))
+
+        self.findPresets()
+
+        # window
+        self.lastFilter = '*'
+        self.presetRows = []  # list of (comp, vers, name) tuples
+        self.window = window
+        self.window.setWindowFlags(QtCore.Qt.WindowStaysOnTopHint)
+
+        # connect button signals
+        self.window.pushButton_delete.clicked.connect(
+            self.openDeletePresetDialog
+        )
+        self.window.pushButton_rename.clicked.connect(
+            self.openRenamePresetDialog
+        )
+        self.window.pushButton_import.clicked.connect(
+            self.openImportDialog
+        )
+        self.window.pushButton_export.clicked.connect(
+            self.openExportDialog
+        )
+        self.window.pushButton_close.clicked.connect(
+            self.window.close
+        )
+
+        # create filter box and preset list
+        self.drawFilterList()
+        self.window.comboBox_filter.currentIndexChanged.connect(
+            lambda: self.drawPresetList(
+                self.window.comboBox_filter.currentText(),
+                self.window.lineEdit_search.text()
+            )
+        )
+
+        # make auto-completion for search bar
+        self.autocomplete = QtCore.QStringListModel()
+        completer = QtWidgets.QCompleter()
+        completer.setModel(self.autocomplete)
+        self.window.lineEdit_search.setCompleter(completer)
+        self.window.lineEdit_search.textChanged.connect(
+            lambda: self.drawPresetList(
+                self.window.comboBox_filter.currentText(),
+                self.window.lineEdit_search.text()
+            )
+        )
+        self.drawPresetList('*')
+
+    def show(self):
+        '''Open a new preset manager window from the mainwindow'''
+        self.findPresets()
+        self.drawFilterList()
+        self.drawPresetList('*')
+        self.window.show()
+
+    def findPresets(self):
+        parseList = []
+        for dirpath, dirnames, filenames in os.walk(self.presetDir):
+            # anything without a subdirectory must be a preset folder
+            if dirnames:
+                continue
+            for preset in filenames:
+                compName = os.path.basename(os.path.dirname(dirpath))
+                if compName not in self.core.compNames:
+                    continue
+                compVers = os.path.basename(dirpath)
+                try:
+                    parseList.append((compName, int(compVers), preset))
+                except ValueError:
+                    continue
+        self.presets = {
+            compName: [
+                (vers, preset)
+                for name, vers, preset in parseList
+                if name == compName
+            ]
+            for compName, _, __ in parseList
+        }
+
+    def drawPresetList(self, compFilter=None, presetFilter=''):
+        self.window.listWidget_presets.clear()
+        if compFilter:
+            self.lastFilter = str(compFilter)
+        else:
+            compFilter = str(self.lastFilter)
+        self.presetRows = []
+        presetNames = []
+        for component, presets in self.presets.items():
+            if compFilter != '*' and component != compFilter:
+                continue
+            for vers, preset in presets:
+                if not presetFilter or presetFilter in preset:
+                    self.window.listWidget_presets.addItem(
+                        '%s: %s' % (component, preset)
+                    )
+                    self.presetRows.append((component, vers, preset))
+                if preset not in presetNames:
+                    presetNames.append(preset)
+        self.autocomplete.setStringList(presetNames)
+
+    def drawFilterList(self):
+        self.window.comboBox_filter.clear()
+        self.window.comboBox_filter.addItem('*')
+        for component in self.presets:
+            self.window.comboBox_filter.addItem(component)
+
+    def clearPreset(self, compI=None):
+        '''Functions on mainwindow level from the context menu'''
+        compI = self.parent.window.listWidget_componentList.currentRow()
+        self.core.clearPreset(compI)
+        self.parent.updateComponentTitle(compI, False)
+
+    def openSavePresetDialog(self):
+        '''Functions on mainwindow level from the context menu'''
+        window = self.parent.window
+        selectedComponents = self.core.selectedComponents
+        componentList = self.parent.window.listWidget_componentList
+
+        if componentList.currentRow() == -1:
+            return
+        while True:
+            index = componentList.currentRow()
+            currentPreset = selectedComponents[index].currentPreset
+            newName, OK = QtWidgets.QInputDialog.getText(
+                self.parent.window,
+                'Audio Visualizer',
+                'New Preset Name:',
+                QtWidgets.QLineEdit.Normal,
+                currentPreset
+            )
+            if OK:
+                if badName(newName):
+                    self.warnMessage(self.parent.window)
+                    continue
+                if newName:
+                    if index != -1:
+                        selectedComponents[index].currentPreset = newName
+                        saveValueStore = \
+                            selectedComponents[index].savePreset()
+                        saveValueStore['preset'] = newName
+                        componentName = str(selectedComponents[index]).strip()
+                        vers = selectedComponents[index].version
+                        self.createNewPreset(
+                            componentName, vers, newName,
+                            saveValueStore, window=self.parent.window)
+                        self.findPresets()
+                        self.drawPresetList()
+                        self.openPreset(newName, index)
+            break
+
+    def createNewPreset(
+            self, compName, vers, filename, saveValueStore, **kwargs):
+        path = os.path.join(self.presetDir, compName, str(vers), filename)
+        if self.presetExists(path, **kwargs):
+            return
+        self.core.createPresetFile(compName, vers, filename, saveValueStore)
+
+    def presetExists(self, path, **kwargs):
+        if os.path.exists(path):
+            window = self.window \
+                if 'window' not in kwargs else kwargs['window']
+            ch = self.parent.showMessage(
+                msg="%s already exists! Overwrite it?" %
+                    os.path.basename(path),
+                showCancel=True,
+                icon='Warning',
+                parent=window)
+            if not ch:
+                # user clicked cancel
+                return True
+
+        return False
+
+    def openPreset(self, presetName, compPos=None):
+        componentList = self.parent.window.listWidget_componentList
+        selectedComponents = self.core.selectedComponents
+
+        index = compPos if compPos is not None else componentList.currentRow()
+        if index == -1:
+            return
+        componentName = str(selectedComponents[index]).strip()
+        version = selectedComponents[index].version
+        dirname = os.path.join(self.presetDir, componentName, str(version))
+        filepath = os.path.join(dirname, presetName)
+        self.core.openPreset(filepath, index, presetName)
+
+        self.parent.updateComponentTitle(index)
+        self.parent.drawPreview()
+
+    def openDeletePresetDialog(self):
+        row = self.getPresetRow()
+        if row == -1:
+            return
+        comp, vers, name = self.presetRows[row]
+        ch = self.parent.showMessage(
+            msg='Really delete %s?' % name,
+            showCancel=True,
+            icon='Warning',
+            parent=self.window
+        )
+        if not ch:
+            return
+        self.deletePreset(comp, vers, name)
+        self.findPresets()
+        self.drawPresetList()
+
+        for i, comp in enumerate(self.core.selectedComponents):
+            if comp.currentPreset == name:
+                self.clearPreset(i)
+
+    def deletePreset(self, comp, vers, name):
+        filepath = os.path.join(self.presetDir, comp, str(vers), name)
+        os.remove(filepath)
+
+    def warnMessage(self, window=None):
+        self.parent.showMessage(
+            msg='Preset names must contain only letters, '
+            'numbers, and spaces.',
+            parent=window if window else self.window)
+
+    def getPresetRow(self):
+        row = self.window.listWidget_presets.currentRow()
+        if row > -1:
+            return row
+
+        # check if component selected in MainWindow has preset loaded
+        componentList = self.parent.window.listWidget_componentList
+        compIndex = componentList.currentRow()
+        if compIndex == -1:
+            return compIndex
+
+        preset = self.core.selectedComponents[compIndex].currentPreset
+        if preset is None:
+            return -1
+        else:
+            rowTuple = (
+                self.core.selectedComponents[compIndex].name,
+                self.core.selectedComponents[compIndex].version,
+                preset
+            )
+            for i, tup in enumerate(self.presetRows):
+                if rowTuple == tup:
+                    index = i
+                    break
+            else:
+                    return -1
+        return index
+
+    def openRenamePresetDialog(self):
+        # TODO: maintain consistency by changing this to call createNewPreset()
+        presetList = self.window.listWidget_presets
+        index = self.getPresetRow()
+        if index == -1:
+            return
+
+        while True:
+            newName, OK = QtWidgets.QInputDialog.getText(
+                self.window,
+                'Preset Manager',
+                'Rename Preset:',
+                QtWidgets.QLineEdit.Normal,
+                self.presetRows[index][2]
+            )
+            if OK:
+                if badName(newName):
+                    self.warnMessage()
+                    continue
+                if newName:
+                    comp, vers, oldName = self.presetRows[index]
+                    path = os.path.join(
+                        self.presetDir, comp, str(vers))
+                    newPath = os.path.join(path, newName)
+                    oldPath = os.path.join(path, oldName)
+                    if self.presetExists(newPath):
+                        return
+                    if os.path.exists(newPath):
+                        os.remove(newPath)
+                    os.rename(oldPath, newPath)
+                    self.findPresets()
+                    self.drawPresetList()
+                    for i, comp in enumerate(self.core.selectedComponents):
+                        if getPresetDir(comp) == path \
+                                and comp.currentPreset == oldName:
+                            self.core.openPreset(newPath, i, newName)
+                            self.parent.updateComponentTitle(i, False)
+                            self.parent.drawPreview()
+            break
+
+    def openImportDialog(self):
+        filename, _ = QtWidgets.QFileDialog.getOpenFileName(
+            self.window, "Import Preset File",
+            self.settings.value("presetDir"),
+            "Preset Files (*.avl)")
+        if filename:
+            # get installed path & ask user to overwrite if needed
+            path = ''
+            while True:
+                if path:
+                    if self.presetExists(path):
+                        break
+                    else:
+                        if os.path.exists(path):
+                            os.remove(path)
+                success, path = self.core.importPreset(filename)
+                if success:
+                    break
+
+            self.findPresets()
+            self.drawPresetList()
+            self.settings.setValue("presetDir", os.path.dirname(filename))
+
+    def openExportDialog(self):
+        index = self.getPresetRow()
+        if index == -1:
+            return
+        filename, _ = QtWidgets.QFileDialog.getSaveFileName(
+            self.window, "Export Preset",
+            self.settings.value("presetDir"),
+            "Preset Files (*.avl)")
+        if filename:
+            comp, vers, name = self.presetRows[index]
+            if not self.core.exportPreset(filename, comp, vers, name):
+                self.parent.showMessage(
+                    msg='Couldn\'t export %s.' % filename,
+                    parent=self.window
+                )
+            self.settings.setValue("presetDir", os.path.dirname(filename))
+
+    def clearPresetListSelection(self):
+        self.window.listWidget_presets.setCurrentRow(-1)
+
+
+def getPresetDir(comp):
+    '''Get the preset subdir for a particular version of a component'''
+    return os.path.join(Core.presetDir, str(comp), str(comp.version))
diff --git a/src/gui/presetmanager.ui b/src/gui/presetmanager.ui
new file mode 100644
index 0000000..5257b1c
--- /dev/null
+++ b/src/gui/presetmanager.ui
@@ -0,0 +1,150 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>presetmanager</class>
+ <widget class="QWidget" name="presetmanager">
+  <property name="windowModality">
+   <enum>Qt::NonModal</enum>
+  </property>
+  <property name="enabled">
+   <bool>true</bool>
+  </property>
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>497</width>
+    <height>377</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Preset Manager</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout_3">
+     <item>
+      <widget class="QLineEdit" name="lineEdit_search">
+       <property name="text">
+        <string/>
+       </property>
+       <property name="placeholderText">
+        <string>Filter by name</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QComboBox" name="comboBox_filter">
+       <property name="minimumSize">
+        <size>
+         <width>200</width>
+         <height>0</height>
+        </size>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout">
+     <item>
+      <widget class="QListWidget" name="listWidget_presets">
+       <property name="sizePolicy">
+        <sizepolicy hsizetype="Expanding" vsizetype="Expanding">
+         <horstretch>0</horstretch>
+         <verstretch>0</verstretch>
+        </sizepolicy>
+       </property>
+       <property name="tabKeyNavigation">
+        <bool>true</bool>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout_2">
+     <property name="sizeConstraint">
+      <enum>QLayout::SetMinimumSize</enum>
+     </property>
+     <item>
+      <widget class="QPushButton" name="pushButton_import">
+       <property name="text">
+        <string>Import</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QPushButton" name="pushButton_export">
+       <property name="text">
+        <string>Export</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <spacer name="horizontalSpacer">
+       <property name="orientation">
+        <enum>Qt::Horizontal</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>40</width>
+         <height>20</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+     <item>
+      <widget class="QPushButton" name="pushButton_rename">
+       <property name="enabled">
+        <bool>true</bool>
+       </property>
+       <property name="text">
+        <string>Rename</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <widget class="QPushButton" name="pushButton_delete">
+       <property name="text">
+        <string>Delete</string>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
+   <item>
+    <layout class="QHBoxLayout" name="horizontalLayout_4">
+     <item alignment="Qt::AlignRight">
+      <widget class="QLabel" name="label">
+       <property name="text">
+        <string>&lt;html&gt;&lt;head/&gt;&lt;body&gt;&lt;p&gt;&lt;span style=&quot; font-size:10pt; font-style:italic;&quot;&gt;Right-click components in the main window to create presets&lt;/span&gt;&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+       </property>
+      </widget>
+     </item>
+     <item>
+      <spacer name="horizontalSpacer_2">
+       <property name="orientation">
+        <enum>Qt::Horizontal</enum>
+       </property>
+       <property name="sizeHint" stdset="0">
+        <size>
+         <width>40</width>
+         <height>20</height>
+        </size>
+       </property>
+      </spacer>
+     </item>
+     <item>
+      <widget class="QPushButton" name="pushButton_close">
+       <property name="text">
+        <string>Close</string>
+       </property>
+      </widget>
+     </item>
+    </layout>
+   </item>
+  </layout>
+ </widget>
+ <resources/>
+ <connections/>
+</ui>
diff --git a/src/gui/preview_thread.py b/src/gui/preview_thread.py
new file mode 100644
index 0000000..9615884
--- /dev/null
+++ b/src/gui/preview_thread.py
@@ -0,0 +1,90 @@
+'''
+    Thread that runs to create QImages for MainWindow's preview label.
+    Processes a queue of component lists.
+'''
+from PyQt5 import QtCore, QtGui, uic
+from PyQt5.QtCore import pyqtSignal, pyqtSlot
+from PIL import Image
+from PIL.ImageQt import ImageQt
+from queue import Queue, Empty
+import os
+import logging
+
+from toolkit.frame import Checkerboard
+from toolkit import disableWhenOpeningProject
+
+
+log = logging.getLogger("AVP.PreviewThread")
+
+
+class Worker(QtCore.QObject):
+
+    imageCreated = pyqtSignal(QtGui.QImage)
+    error = pyqtSignal(str)
+
+    def __init__(self, parent=None, queue=None):
+        QtCore.QObject.__init__(self)
+        parent.newTask.connect(self.createPreviewImage)
+        parent.processTask.connect(self.process)
+        self.parent = parent
+        self.core = parent.core
+        self.settings = parent.settings
+        self.queue = queue
+
+        width = int(self.settings.value('outputWidth'))
+        height = int(self.settings.value('outputHeight'))
+        self.background = Checkerboard(width, height)
+
+    @disableWhenOpeningProject
+    @pyqtSlot(list)
+    def createPreviewImage(self, components):
+        dic = {
+          "components": components,
+        }
+        self.queue.put(dic)
+
+    @pyqtSlot()
+    def process(self):
+        width = int(self.settings.value('outputWidth'))
+        height = int(self.settings.value('outputHeight'))
+        try:
+            nextPreviewInformation = self.queue.get(block=False)
+            while self.queue.qsize() >= 2:
+                try:
+                    self.queue.get(block=False)
+                except Empty:
+                    continue
+            if self.background.width != width \
+                    or self.background.height != height:
+                self.background = Checkerboard(width, height)
+
+            frame = self.background.copy()
+            log.debug('Creating new preview frame')
+            components = nextPreviewInformation["components"]
+            for component in reversed(components):
+                try:
+                    component.lockSize(width, height)
+                    newFrame = component.previewRender()
+                    component.unlockSize()
+                    frame = Image.alpha_composite(
+                        frame, newFrame
+                    )
+
+                except ValueError as e:
+                    errMsg = "Bad frame returned by %s's preview renderer. " \
+                        "%s. New frame size was %s*%s; should be %s*%s." % (
+                            str(component), str(e).capitalize(),
+                            newFrame.width, newFrame.height,
+                            width, height
+                        )
+                    log.critical(errMsg)
+                    self.error.emit(errMsg)
+                    break
+                except RuntimeError as e:
+                    log.error(str(e))
+            else:
+                self.frame = ImageQt(frame)
+                self.imageCreated.emit(QtGui.QImage(self.frame))
+
+        except Empty:
+            True
diff --git a/src/gui/preview_win.py b/src/gui/preview_win.py
new file mode 100644
index 0000000..40c19c6
--- /dev/null
+++ b/src/gui/preview_win.py
@@ -0,0 +1,62 @@
+from PyQt5 import QtCore, QtGui, QtWidgets
+import logging
+
+
+class PreviewWindow(QtWidgets.QLabel):
+    '''
+        Paints the preview QLabel in MainWindow and maintains the aspect ratio
+        when the window is resized.
+    '''
+    log = logging.getLogger('AVP.PreviewWindow')
+
+    def __init__(self, parent, img):
+        super(PreviewWindow, self).__init__()
+        self.parent = parent
+        self.setFrameStyle(QtWidgets.QFrame.StyledPanel)
+        self.pixmap = QtGui.QPixmap(img)
+
+    def paintEvent(self, event):
+        size = self.size()
+        painter = QtGui.QPainter(self)
+        point = QtCore.QPoint(0, 0)
+        scaledPix = self.pixmap.scaled(
+            size,
+            QtCore.Qt.KeepAspectRatio,
+            transformMode=QtCore.Qt.SmoothTransformation)
+
+        # start painting the label from left upper corner
+        point.setX((size.width() - scaledPix.width())/2)
+        point.setY((size.height() - scaledPix.height())/2)
+        painter.drawPixmap(point, scaledPix)
+
+    def changePixmap(self, img):
+        self.pixmap = QtGui.QPixmap(img)
+        self.repaint()
+
+    def mousePressEvent(self, event):
+        if self.parent.encoding:
+            return
+
+        i = self.parent.window.listWidget_componentList.currentRow()
+        if i >= 0:
+            component = self.parent.core.selectedComponents[i]
+            if not hasattr(component, 'previewClickEvent'):
+                self.log.info('Ignored click event')
+                return
+            pos = (event.x(), event.y())
+            size = (self.width(), self.height())
+            butt = event.button()
+            self.log.info('Click event for #%s: %s button %s' % (
+                i, pos, butt))
+            component.previewClickEvent(
+                pos, size, butt
+            )
+            self.parent.core.updateComponent(i)
+
+    @QtCore.pyqtSlot(str)
+    def threadError(self, msg):
+        self.parent.showMessage(
+            msg=msg,
+            icon='Critical',
+            parent=self
+        )