def _initgworld(self):
old_port, old_dev = Qdoffs.GetGWorld()
try:
movie_w = self.videodescr['width']
movie_h = self.videodescr['height']
movie_rect = (0, 0, movie_w, movie_h)
self.gworld = Qdoffs.NewGWorld(32, movie_rect, None, None, QDOffscreen.keepLocal)
self.pixmap = self.gworld.GetGWorldPixMap()
Qdoffs.LockPixels(self.pixmap)
Qdoffs.SetGWorld(self.gworld.as_GrafPtr(), None)
Qd.EraseRect(movie_rect)
self.movie.SetMovieGWorld(self.gworld.as_GrafPtr(), None)
self.movie.SetMovieBox(movie_rect)
self.movie.SetMovieActive(1)
self.movie.MoviesTask(0)
self.movie.SetMoviePlayHints(QuickTime.hintsHighQuality, QuickTime.hintsHighQuality)
# XXXX framerate
finally:
Qdoffs.SetGWorld(old_port, old_dev)
def readFrame(inputMovieName, outputImageName, frameNumber):
try: os.unlink(outputImageName) # delete the existing outputImageName, if it exists
except: pass
try:
Qt.EnterMovies()
fd = Qt.OpenMovieFile(inputMovieName, 0)
movie, junk1, junk2 = Qt.NewMovieFromFile(fd, 0, 0)
try:
videotrack = movie.GetMovieIndTrackType(1, QuickTime.VisualMediaCharacteristic, QuickTime.movieTrackCharacteristic)
videomedia = videotrack.GetTrackMedia()
except Qt.Error:
videotrack = videomedia = None
if videotrack:
x0, y0, x1, y1 = movie.GetMovieBox()
width, height = x1-x0, y1-y0
old_port, old_dev = Qdoffs.GetGWorld()
try:
movie_rect = (0, 0, width, height)
gworld = Qdoffs.NewGWorld(32, movie_rect, None, None, QDOffscreen.keepLocal)
pixmap = gworld.GetGWorldPixMap()
Qdoffs.LockPixels(pixmap)
Qdoffs.SetGWorld(gworld.as_GrafPtr(), None)
Qd.EraseRect(movie_rect)
movie.SetMovieGWorld(gworld.as_GrafPtr(), None)
movie.SetMovieBox(movie_rect)
movie.SetMovieActive(1)
movie.MoviesTask(0)
movie.SetMoviePlayHints(QuickTime.hintsHighQuality, QuickTime.hintsHighQuality)
finally:
Qdoffs.SetGWorld(old_port, old_dev)
# finished with Quicktime initialization
QTSearchFlags = QuickTime.nextTimeMediaSample|QuickTime.nextTimeEdgeOK
startTime, frameDuration = videomedia.GetMediaNextInterestingTime(QTSearchFlags, 0, 1.0)
# startTime is time at start of movie (start offset)
# frameDuration is the number of video time units that pass each frame (in videotimescale units)
if debug: print "frameDuration", frameDuration
movieDuration = videotrack.GetTrackDuration() # in movietimescale units
if debug: print "movieDuration", movieDuration
movietimescale = movie.GetMovieTimeScale()
if debug: print "movietimescale", movietimescale
videotimescale = videomedia.GetMediaTimeScale()
if debug: print "videotimescale", videotimescale
movieDurationSeconds = float(movieDuration) / movietimescale
if debug: print "movieDurationSeconds", movieDurationSeconds
frameLengthSeconds = float(frameDuration) / videotimescale
if debug: print "frameLengthSeconds", frameLengthSeconds, "(inverse)", 1.0/frameLengthSeconds
totalFrames = movieDurationSeconds / frameLengthSeconds
if debug: print "totalFrames", totalFrames, "(rounded)", int(round(totalFrames))
frames = int(round(totalFrames))
if debug: print "reading frame", frameNumber, "at videotime", startTime+frameNumber*frameDuration
timestamp = videomedia.GetMediaNextInterestingTimeOnly(QTSearchFlags, startTime+frameNumber*frameDuration, 1)
if timestamp < 0:
raise "Quicktime error", "error %s, frame search failed at videotime %s" % (timestamp,startTime+frameNumber*frameDuration)
moviecurtime, junk1, junk2 = Qt.ConvertTimeScale((timestamp, videotimescale, None), movietimescale)
# I don't know why this time adjustment is needed, but it sometimes seeks to the wrong frame without it
movieframetime, junk1, junk2 = Qt.ConvertTimeScale((frameDuration, videotimescale, None), movietimescale)
if debug: print "movieframetime", movieframetime
if movieframetime > 1:
moviecurtime += 1
movie.SetMovieTimeValue(moviecurtime)
movie.MoviesTask(0)
# shuffle the offscreen PixMap data, because it may have funny stride values and alpha channel
rowbytes = Qdoffs.GetPixRowBytes(pixmap)
start = 0
rv = []
for i in range(height):
nextline = Qdoffs.GetPixMapBytes(pixmap, start, width*4)
for j in range(width):
rgb = nextline[4*j+1:4*j+4] # skip alpha plane data at nextline[4*j]
rv.append(rgb)
start = start + rowbytes
data = string.join(rv, '')
if debug: print "timestamp found", timestamp, "length of image data", len(data)
videomedia = videotrack = movie = None # this is required to deallocate memory
except Exception, err:
writeError(outputImageName, err.__str__())
# Video file reader, using QuickTime