Change #273936

Comments

libavformat/img2enc: add update_filemtime option
Add a new boolean option -update_filemtime to the image2 muxer that
sets each output file's modification time based on the creation_time
metadata plus the frame's PTS offset.

This is useful when extracting frames from dashcam or action camera
footage where wall-clock timestamps should be preserved on the output
files, allowing photo management tools to sort frames by capture time
without post-processing.

The option requires creation_time metadata to be set (via -metadata
creation_time=...). If not present, a warning is logged and the
option is silently disabled. When PTS is unavailable, the creation
time is used as-is without frame offset.

Uses utimes() on POSIX and _utime() on Windows to set file timestamps
with microsecond and second precision respectively.

Includes a FATE roundtrip test that writes frames with a known
creation_time, reads them back using the demuxer's -ts_from_file
option, and verifies the PTS values match the expected timestamps.

Closes: https://code.ffmpeg.org/FFmpeg/FFmpeg/issues/22537
Signed-off-by: marcos ashton <marcosashiglesias@gmail.com>

Changed files

• doc/muxers.texi
• libavformat/img2enc.c
• tests/fate-run.sh
• tests/fate/image.mak
• tests/ref/fate/img2-update-filemtime