threading together some screenshot pngs to video

get_image_info.py

def get_image_info(data):
    """
    FROM http://markasread.net/post/17551554979/get-image-size-info-using-pure-python-code

    Return (content_type, width, height) for a given img file content
    no requirements
    """
    import struct
    
    data = str(data)
    size = len(data)
    height = -1
    width = -1
    content_type = ''

    # handle GIFs
    if (size >= 10) and data[:6] in ('GIF87a', 'GIF89a'):
        # Check to see if content_type is correct
        content_type = 'image/gif'
        w, h = struct.unpack("<HH", data[6:10])
        width = int(w)
        height = int(h)

    # See PNG 2. Edition spec (http://www.w3.org/TR/PNG/)
    # Bytes 0-7 are below, 4-byte chunk length, then 'IHDR'
    # and finally the 4-byte width, height
    elif ((size >= 24) and data.startswith('\211PNG\r\n\032\n')
          and (data[12:16] == 'IHDR')):
        content_type = 'image/png'
        w, h = struct.unpack(">LL", data[16:24])
        width = int(w)
        height = int(h)

    # Maybe this is for an older PNG version.
    elif (size >= 16) and data.startswith('\211PNG\r\n\032\n'):
        # Check to see if we have the right content type
        content_type = 'image/png'
        w, h = struct.unpack(">LL", data[8:16])
        width = int(w)
        height = int(h)

    # handle JPEGs
    elif (size >= 2) and data.startswith('\377\330'):
        content_type = 'image/jpeg'
        jpeg = StringIO(data)
        jpeg.read(2)
        b = jpeg.read(1)
        try:
            while (b and ord(b) != 0xDA):
                while (ord(b) != 0xFF): b = jpeg.read
                while (ord(b) == 0xFF): b = jpeg.read(1)
                if (ord(b) >= 0xC0 and ord(b) <= 0xC3):
                    jpeg.read(3)
                    h, w = struct.unpack(">HH", jpeg.read(4))
                    break
                else:
                    jpeg.read(int(struct.unpack(">H", jpeg.read(2))[0])-2)
                b = jpeg.read(1)
            width = int(w)
            height = int(h)
        except struct.error:
            pass
        except ValueError:
            pass

    return content_type, width, height

images_to_video.py

import os
from sys import argv, exit

def images_to_vid(in_folder, out_file=None, img_sentenel=None, vid_type=None, frame_rate=None):
	if not os.path.exists(in_folder):
		print "%s does not exist!" % in_folder
		return False

	if img_sentenel is None:
		img_sentenel = "screenshot_"

	img_info = None

	import re
	for _, _, files in os.walk(in_folder):
		files = [f for f in files if re.match(re.compile("^%s" % img_sentenel), f) is not None]
		try:
			files = sorted(files, key=lambda f: int(f.split(img_sentenel)[1].split('.')[0]))
		except Exception as e:
			print e
			return False

		for f in files:
			if re.match(re.compile("^%s" % img_sentenel), f):
				from get_image_info import get_image_info
				with open(f, 'rb') as img:
					img_info = get_image_info(img.read())
				

				break

	if img_info is None:
		print "no info for any images in folder"
		return False

	sequence_start = None
	try:
		sequence_start = "-start_number %d " % int(files[0].split(img_sentenel)[1].split('.')[0])
	except Exception as e:
		print e

	img_type = None

	if img_info[0] == "image/png":
		img_type = "png"
	if img_info[0] == "image/jpeg":
		img_type = "jpg"

	if img_type is None:
		print "cannot determine image type"
		return False

	if out_file is None:
		from time import time
		out_file = "images_to_vid_%d" % time()

	if vid_type is None:
		vid_type = "mp4"

	if frame_rate is None:
		frame_rate = 2

	mapping = {
		'r' : frame_rate,
		'is' : img_sentenel,
		'is' : "{0}%05d.{1}".format(img_sentenel, img_type),
		'vw' : img_info[1],
		'vh' : img_info[2],
		'of' : "%s.%s" % (out_file, vid_type),
		'ss' : "" if sequence_start is None else sequence_start
	}

	from fabric.api import settings, local

	with settings(warn_only=True):
		ffmpeg_cmd = "ffmpeg -y -r %(r)d %(ss)s-i %(is)s -s %(vw)dx%(vh)d -c:v libx264 -crf 23 -pix_fmt yuv420p %(of)s" % mapping
		res = local(ffmpeg_cmd, capture=True)

		print res
		return True

	return False


if __name__ == "__main__":
	if len(argv) < 2:
		print "usage: images_to_vid.py in_folder [out_file, vid_type, frame_rate]"
		exit(-1)

	out_file = None if len(argv) < 3 else argv[2]
	frame_rate = None if len(argv) < 4 else int(argv[3])
	vid_type = None if len(argv) < 5 else argv[4]
	img_sentenel = None if len(argv) < 6 else argv[5]

	this_dir = os.getcwd()
	os.chdir(argv[1])
	res = images_to_vid(argv[1], out_file=out_file, img_sentenel=img_sentenel, vid_type=vid_type, frame_rate=frame_rate)

	os.chdir(this_dir)
	if res:
		exit(0)

	exit(-1)