HDR color primaries and luminance passthrough options

x265_passthrough.py

#!/usr/bin/env python
from subprocess import run, PIPE
import re
import sys
import json 

su = re.compile(r'",\s*}')


def run_ffprobe(video_file):
    command = (f'ffprobe "{video_file}" -show_streams -select_streams v:0 -read_intervals "%+#10" '
               f'-show_frames -show_entries side_data -v quiet -pretty -print_format json -of json')
    result = run(command, stdout=PIPE)
    if result.returncode != 0:
        raise Exception(f"Error while running ffprobe {result}")
    return json.loads(su.sub('"}', result.stdout.decode("utf-8")))


def parse_json(data):
    master_display_raw = None
    max_cll = 0
    max_fall = 0
    for frame in data["packets_and_frames"]:
        if frame["type"] != "frame" or "side_data_list" not in frame:
            continue
        for item in frame["side_data_list"]:
            if not master_display_raw and item["side_data_type"] == "Mastering display metadata":
                master_display_raw = item
            if item["side_data_type"] == "Content light level metadata":
                max_cll = item["max_content"]
                max_fall = item["max_average"]

    if not master_display_raw:
        if data["streams"][0]["codec_tag_string"] == "dvhe":
            raise Exception("This is a dolby vision file, No master display data provided")
        raise Exception("No master display data found")

    del master_display_raw['side_data_type']
    for key in master_display_raw.keys():
        master_display_raw[key] = master_display_raw[key].split("/")[0]

    return master_display_raw, max_cll, max_fall


if __name__ == '__main__':
    video = sys.argv[1]

    ffprobe_output = run_ffprobe(video)
    main_stream = ffprobe_output["streams"][0]
    mdr, cll, fall = parse_json(ffprobe_output)

    master_display = ("master-display="
                      f"G({mdr['green_x']},{mdr['green_y']})"
                      f"B({mdr['blue_x']},{mdr['blue_y']})"
                      f"R({mdr['red_x']},{mdr['red_y']})"
                      f"WP({mdr['white_point_x']},{mdr['white_point_y']})"
                      f"L({mdr['max_luminance']},{mdr['min_luminance']})")

    max_lum = f"max-cll={cll},{fall}"

    params = (f'-pix_fmt {main_stream["pix_fmt"]} -x265-params '
              f'"aq-mode=1:'
              f'colorprim={main_stream["color_primaries"]}:'
              f'colormatrix={main_stream["color_space"]}:'
              f'transfer={main_stream["color_transfer"]}:'
              f'chromaloc=2:'
              f'{master_display}:'
              f'{max_lum}:'
              f'hdr-opt=1:hdr=1:info=1:repeat-headers=1"')

    print(params)

$ x265_passthrough.py video.mkv

-pix_fmt yuv420p10le -x265-params "aq-mode=1:colorprim=bt2020:colormatrix=bt2020nc:transfer=smpte2084:chromaloc=2:master-display=G(13250,34500)B(7500,3000)R(34000,16000)WP(15635,16450)L(10000000,1):max-cll=0,0:hdr-opt=1:hdr=1:info=1:repeat-headers=1"