pyaudviz/src/components/video.py

from PIL import Image, ImageDraw
from PyQt5 import uic, QtGui, QtCore, QtWidgets
import os
import subprocess
import threading
from queue import PriorityQueue
from . import __base__


class Video:
    '''Video Component Frame-Fetcher'''
    def __init__(self, **kwargs):
        mandatoryArgs = [
            'ffmpeg',     # path to ffmpeg, usually core.FFMPEG_BIN
            'videoPath',
            'width',
            'height',
            'scale',      # percentage scale
            'frameRate',  # frames per second
            'chunkSize',  # number of bytes in one frame
            'parent',     # mainwindow object
            'component',  # component object
        ]
        for arg in mandatoryArgs:
            try:
                exec('self.%s = kwargs[arg]' % arg)
            except KeyError:
                raise __base__.BadComponentInit(arg, self.__doc__)

        self.frameNo = -1
        self.currentFrame = 'None'
        if 'loopVideo' in kwargs and kwargs['loopVideo']:
            self.loopValue = '-1'
        else:
            self.loopValue = '0'
        self.command = [
            self.ffmpeg,
            '-thread_queue_size', '512',
            '-r', str(self.frameRate),
            '-stream_loop', self.loopValue,
            '-i', self.videoPath,
            '-f', 'image2pipe',
            '-pix_fmt', 'rgba',
            '-filter:v', 'scale=%s:%s' % scale(
                self.scale, self.width, self.height, str),
            '-vcodec', 'rawvideo', '-',
        ]

        self.frameBuffer = PriorityQueue()
        self.frameBuffer.maxsize = self.frameRate
        self.finishedFrames = {}

        self.thread = threading.Thread(
            target=self.fillBuffer,
            name=self.__doc__
        )
        self.thread.daemon = True
        self.thread.start()

    def frame(self, num):
        while True:
            if num in self.finishedFrames:
                image = self.finishedFrames.pop(num)
                return finalizeFrame(
                    self.component, image, self.width, self.height)

            i, image = self.frameBuffer.get()
            self.finishedFrames[i] = image
            self.frameBuffer.task_done()

    def fillBuffer(self):
        pipe = subprocess.Popen(
            self.command, stdout=subprocess.PIPE,
            stderr=subprocess.DEVNULL, bufsize=10**8
        )
        while True:
            if self.parent.canceled:
                break
            self.frameNo += 1

            # If we run out of frames, use the last good frame and loop.
            if len(self.currentFrame) == 0:
                self.frameBuffer.put((self.frameNo-1, self.lastFrame))
                continue

            self.currentFrame = pipe.stdout.read(self.chunkSize)
            if len(self.currentFrame) != 0:
                self.frameBuffer.put((self.frameNo, self.currentFrame))
                self.lastFrame = self.currentFrame


class Component(__base__.Component):
    '''Video'''

    modified = QtCore.pyqtSignal(int, dict)

    def widget(self, parent):
        self.parent = parent
        self.settings = parent.settings
        page = uic.loadUi(os.path.join(
            os.path.dirname(os.path.realpath(__file__)),
            'video.ui'
        ))
        self.videoPath = ''
        self.x = 0
        self.y = 0
        self.loopVideo = False

        page.lineEdit_video.textChanged.connect(self.update)
        page.pushButton_video.clicked.connect(self.pickVideo)
        page.checkBox_loop.stateChanged.connect(self.update)
        page.checkBox_distort.stateChanged.connect(self.update)
        page.spinBox_scale.valueChanged.connect(self.update)
        page.spinBox_x.valueChanged.connect(self.update)
        page.spinBox_y.valueChanged.connect(self.update)

        self.page = page
        return page

    def update(self):
        self.videoPath = self.page.lineEdit_video.text()
        self.loopVideo = self.page.checkBox_loop.isChecked()
        self.distort = self.page.checkBox_distort.isChecked()
        self.scale = self.page.spinBox_scale.value()
        self.xPosition = self.page.spinBox_x.value()
        self.yPosition = self.page.spinBox_y.value()
        self.parent.drawPreview()
        super().update()

    def previewRender(self, previewWorker):
        self.videoFormats = previewWorker.core.videoFormats
        width = int(previewWorker.core.settings.value('outputWidth'))
        height = int(previewWorker.core.settings.value('outputHeight'))
        self.updateChunksize(width, height)
        frame = self.getPreviewFrame(width, height)
        if not frame:
            return self.blankFrame(width, height)
        else:
            return frame

    def preFrameRender(self, **kwargs):
        super().preFrameRender(**kwargs)
        width = int(self.worker.core.settings.value('outputWidth'))
        height = int(self.worker.core.settings.value('outputHeight'))
        self.blankFrame_ = self.blankFrame(width, height)
        self.updateChunksize(width, height)
        self.video = Video(
            ffmpeg=self.parent.core.FFMPEG_BIN, videoPath=self.videoPath,
            width=width, height=height, chunkSize=self.chunkSize,
            frameRate=int(self.settings.value("outputFrameRate")),
            parent=self.parent, loopVideo=self.loopVideo,
            component=self, scale=self.scale
        ) if os.path.exists(self.videoPath) else None

    def frameRender(self, moduleNo, arrayNo, frameNo):
        if self.video:
            return self.video.frame(frameNo)
        else:
            return self.blankFrame_

    def loadPreset(self, pr, presetName=None):
        super().loadPreset(pr, presetName)
        self.page.lineEdit_video.setText(pr['video'])
        self.page.checkBox_loop.setChecked(pr['loop'])
        self.page.checkBox_distort.setChecked(pr['distort'])
        self.page.spinBox_scale.setValue(pr['scale'])
        self.page.spinBox_x.setValue(pr['x'])
        self.page.spinBox_y.setValue(pr['y'])

    def savePreset(self):
        return {
            'preset': self.currentPreset,
            'video': self.videoPath,
            'loop': self.loopVideo,
            'distort': self.distort,
            'scale': self.scale,
            'x': self.xPosition,
            'y': self.yPosition,
        }

    def pickVideo(self):
        imgDir = self.settings.value("backgroundDir", os.path.expanduser("~"))
        filename, _ = QtWidgets.QFileDialog.getOpenFileName(
            self.page, "Choose Video",
            imgDir, "Video Files (%s)" % " ".join(self.videoFormats)
        )
        if filename:
            self.settings.setValue("backgroundDir", os.path.dirname(filename))
            self.page.lineEdit_video.setText(filename)
            self.update()

    def getPreviewFrame(self, width, height):
        if not self.videoPath or not os.path.exists(self.videoPath):
            return

        command = [
            self.parent.core.FFMPEG_BIN,
            '-thread_queue_size', '512',
            '-i', self.videoPath,
            '-f', 'image2pipe',
            '-pix_fmt', 'rgba',
            '-filter:v', 'scale=%s:%s' % scale(
                self.scale, width, height, str),
            '-vcodec', 'rawvideo', '-',
            '-ss', '90',
            '-vframes', '1',
        ]
        pipe = subprocess.Popen(
            command, stdout=subprocess.PIPE,
            stderr=subprocess.DEVNULL, bufsize=10**8
        )
        byteFrame = pipe.stdout.read(self.chunkSize)
        frame = finalizeFrame(self, byteFrame, width, height)
        pipe.stdout.close()
        pipe.kill()

        return frame

    def updateChunksize(self, width, height):
        if self.scale != 100 and not self.distort:
            width, height = scale(self.scale, width, height, int)
        self.chunkSize = 4*width*height

    def command(self, arg):
        if not arg.startswith('preset=') and '=' in arg:
            key, arg = arg.split('=', 1)
            if key == 'path' and os.path.exists(arg):
                if os.path.splitext(arg)[1] in self.core.videoFormats:
                    self.page.lineEdit_video.setText(arg)
                    self.page.spinBox_scale.setValue(100)
                    self.page.checkBox_loop.setChecked(True)
                    return
                else:
                    print("Not a supported video format")
                    quit(1)
        super().command(arg)

    def commandHelp(self):
        print('Load a video:\n    path=/filepath/to/video.mp4')


def scale(scale, width, height, returntype=None):
    width = (float(width) / 100.0) * float(scale)
    height = (float(height) / 100.0) * float(scale)
    if returntype == str:
        return (str(int(width)), str(int(height)))
    elif returntype == int:
        return (int(width), int(height))
    else:
        return (width, height)


def finalizeFrame(self, imageData, width, height):
    if self.distort:
        try:
            image = Image.frombytes(
                'RGBA',
                (width, height),
                imageData)
        except ValueError:
            print('#### ignored invalid data caused by distortion ####')
            image = self.blankFrame(width, height)
    else:
        image = Image.frombytes(
            'RGBA',
            scale(self.scale, width, height, int),
            imageData)

    if self.scale != 100 \
            or self.xPosition != 0 or self.yPosition != 0:
        frame = self.blankFrame(width, height)
        frame.paste(image, box=(self.xPosition, self.yPosition))
    else:
        frame = image
    return frame