Convert image sequences in folders into high quality mp4 video files.

convert_sequences_mp4.py

"""Convert image sequences in dirs found under `datab_root` into high quality mp4 video files.
"""
import argparse
import os
import subprocess

default_codec = "h264"
default_crf = "18"
default_keyint = "4"

def convert_scenes(datab_root, out_root, codec, crf, keyint, quiet):
	# If not provided, set values by default
	if not codec:
		codec = default_codec
	assert codec in ['h264', 'hevc'], '--codec must be one of h264 or hevc'

	if not crf:
		crf = default_crf

	if not keyint:
		keyint = default_keyint

	# Codec options
	codec_args = ["-preset", "slow"]
	if codec == 'h264':
		codec_args = ["-c:v", "libx264", "-g", keyint,
					  "-profile:v", "high"]
	elif codec == 'hevc' or codec == 'h265':
		codec_args = ["-c:v", "libx265", "-x265-params",
					  "keyint=%s:no-open-gop=1" % (keyint)]
	else:
		raise ValueError("Unknown codec")

	# Quiet mode
	if quiet:
		cmdout = subprocess.DEVNULL
	else:
		cmdout = None

	# Output dir
	if not os.path.isdir(out_root):
		os.makedirs(out_root)
	print('Writing sequences to {}'.format(out_root))

	def convert(in_path, out_path):
		cmd = ["ffmpeg", "-y", "-i", in_path]
		cmd += codec_args
		cmd += ["-crf", crf, "-an", out_path]
		print("Running:", " ".join(cmd))
		subprocess.run(cmd, stdout=cmdout, stderr=cmdout)

	# Convert sequences in subdirs under datab_root
	for subdir in os.listdir(datab_root):
		in_path = os.path.join(datab_root, subdir, '%5d.jpg')
		out_path = os.path.join(out_root, subdir + '.mp4')
		convert(in_path, out_path)