Convert video frames to video

images_to_video.py

#
# Convert images to video
#
# Example:
#  python video.py -i 8012 -l 8151 -f 30 -t 800x600/IMG_%FRAME_NUM%_result.jpg
#
# ffmpeg command line from: https://github.com/justin-bennington/somewhere-ml/blob/main/S2_GAN_Art_Generator_(VQGAN%2C_CLIP%2C_Guided_Diffusion).ipynb
#

from PIL import Image
from subprocess import Popen, PIPE


def frames_to_video(init_frame, last_frame, fps, filename_template, video_filename):
    print('Generating video...')
    
    frames = []
    template = filename_template.replace("%FRAME_NUM%", "{i:04}")
    for i in range(init_frame,last_frame):
        filename = template.format(i=i)
        frames.append(Image.open(filename))

    print("Video filename: "+ video_filename)
    
    ffmpeg_cmd = [
        'ffmpeg', '-y',
        '-f', 'image2pipe',
        '-vcodec', 'mjpeg', '-r', str(fps),
        '-i', '-',
        '-vcodec', 'libx264', '-r', str(fps),
        '-pix_fmt', 'yuv420p',
        '-crf', '17',
        '-preset', 'veryslow',
        video_filename
    ]
    p = Popen(ffmpeg_cmd, stdin=PIPE)
    for im in frames:
        im.save(p.stdin, 'JPEG')
    p.stdin.close()

    print("Compressing video...")
    p.wait()
    print("Video ready")


def main():
    import argparse

    parser = argparse.ArgumentParser(prog='frames_to_video')
    parser.add_argument('-i', '--init-frame', type=int, required=True)
    parser.add_argument('-l', '--last-frame', type=int, required=True)
    parser.add_argument('-f', '--fps', type=int, default=6)
    parser.add_argument('-o', '--output', type=str, default="video.mp4", metavar='<path>')
    parser.add_argument('-t', '--template', type=str, metavar='<path>', required=True)
    
    args = parser.parse_args()
    
    fps = args.fps
    init_frame = args.init_frame
    last_frame = args.last_frame
    filename_template = args.template
    video_filename = args.output

    frames_to_video(init_frame, last_frame, fps, filename_template, video_filename)


if __name__ == "__main__":
    main()