framerater.py

#!/usr/bin/python

import Image
import sys

def itergif(gif):
    try:
        gif.seek(0)
        while True:
            yield gif
            gif.seek(gif.tell()+1)
    except EOFError:
        return

def framerate(gif):
    frames = []
    for frame in itergif(gif):
        frames.append(float(frame.info["duration"]))
    average = sum(frames) / len(frames)
    
    for num, frame in enumerate(frames):
        # if the difference between the average and the frame
        difference = abs(average - frame)
        # is more than 5% of the average
        if difference > (average * 0.20):
            raise Exception("frame %d has duration %f, which is more than 20%% different than average of %f" % (num, frame, average))
        if difference > (average * 0.05):
            # then the frame will jitter noticeably as an avi and the user should know
            sys.stderr.write("warning: frame %d has duration %f! (average: %f)\n" % (num, frame, average))
            sys.stderr.flush()
    
    try:
        return 1000.0/average
    except ZeroDivisionError:
        return 25.0

def file_rate(filename):
    return framerate(Image.open(filename))

if __name__ == "__main__":
    print file_rate(sys.argv[-1])

gif2avi.py

import framerater
import os
import subprocess
import tempfile
import sys
import shutil

def command(quitter, *args):
    sys.stderr.write("command: %r\n" % (args,))
    popen = subprocess.Popen(args, stdout=2, stderr=2)
    while True:
        try:
            popen.wait()
            break
        except KeyboardInterrupt:
            quitter.quit()
            continue

class Quitter(object):
    def __init__(self):
        self.quitting = False
    def doquit(self):
        if self.quitting:
            raise KeyboardInterrupt
    def quit(self):
        print "quitting..."
        self.quitting = True 

def name2avi(input):
    output = input
    if output.endswith(".gif"):
        output = output[:-4]
    output = output + ".avi"
    return output

def gif2avi(quitter, input, output=None):
    framerate = framerater.file_rate(input)
    if not output:
        output = name2avi(input)
    if os.path.exists(output):
        raise IOError("file exists: %s" % output)

    tempdir = tempfile.mkdtemp()
    frametemplate = tempdir + "/test%05d.png"
    command(quitter, "/usr/bin/convert", input, "-quality", "10", frametemplate)
    if os.path.exists(output):
        raise IOError("file exists: %s" % output)
    command(quitter, "/usr/bin/ffmpeg", "-r", str(int(framerate)), "-i", frametemplate, output)
    shutil.rmtree(tempdir)
    return output

if __name__ == "__main__":
    print gif2avi(Quitter(), sys.argv[-2], sys.argv[-1])

gifs2avis.py

import os
import glob
import gif2avi
import sys

def gifs2avis(indir, outdir):
    if not os.path.exists(outdir):
        os.makedirs(outdir)
    infiles = glob.glob("%s/*.gif" % indir)
    quitter = gif2avi.Quitter()
    for infile in infiles:
        outfile = gif2avi.name2avi(outdir+"/"+os.path.basename(infile))
        
        stat = os.stat(infile)
        times = (stat.st_atime, stat.st_mtime)
        try:
            gif2avi.gif2avi(quitter, infile, outfile)
        except IOError, e:
            import traceback
            traceback.print_exc()
            continue

        os.utime(outfile, times)
        print infile, outfile
        quitter.doquit()

if __name__ == "__main__":
    gifs2avis(os.path.realpath(sys.argv[-2]),
              os.path.realpath(sys.argv[-1]))