Incorrect cropping via h264_metadata. #16758
Description
mpv Information
mpv v0.40.0-298-gb9ceaf243 Copyright © 2000-2025 mpv/MPlayer/mplayer2 projects
built on Sep 2 2025 20:14:12
libplacebo version: v7.354.0 (v7.351.0-67-g515da95-dirty)
FFmpeg version: N-120956-gc2ce38738
FFmpeg library versions:
libavcodec 62.15.100
libavdevice 62.2.100
libavfilter 11.8.100
libavformat 62.4.102
libavutil 60.11.100
libswresample 6.2.100
libswscale 9.3.100Other Information
- Windows version: Microsoft Windows [Version 10.0.22631.4317]
- GPU model, driver and version: NVIDIA RTX 4070 Super, 552.12
- Source of mpv: https://github.com/zhongfly/mpv-winbuild/releases
- Latest known working version: no known working version
- Issue started after the following happened: no known working version
Reproduction Steps
ffmpeg -y -f lavfi -i testsrc=size=1920x1080 -t 10 -pix_fmt yuv420p testsrc.mp4
ffmpeg -y -i testsrc.mp4 -map 0 -c copy -bsf:v h264_metadata=crop_left=240:crop_right=240 testsrc_cropped.mp4
mpv testsrc_cropped.mp4
Produced file is
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'testsrc_cropped.mp4':
Metadata:
major_brand : isom
minor_version : 512
compatible_brands: isomiso2avc1mp41
encoder : Lavf62.4.100
Duration: 00:00:10.00, start: 0.000000, bitrate: 172 kb/s
Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661), yuv420p(progressive), 1440x1080 [SAR 1:1 DAR 4:3], 169 kb/s, 25 fps, 25 tbr, 12800 tbn (default)
Metadata:
handler_name : VideoHandler
vendor_id : [0][0][0][0]
encoder : Lavc62.13.101 libx264
Expected Behavior
Cropping via h264_metadata is precise.
Actual Behavior
Crops 192 pixels from the left, 240 from the right. The amount of pixels cropped seems to always be a multiple of 16, with no clear rounding.
Log File
Sample Files
No response
I carefully read all instruction and confirm that I did the following:
- I tested with the latest mpv version to validate that the issue is not already fixed.
- I provided all required information including system and mpv version.
- I produced the log file with the exact same set of files, parameters, and conditions used in "Reproduction Steps", with the addition of
--log-file=output.txt. - I produced the log file while the behaviors described in "Actual Behavior" were actively observed.
- I attached the full, untruncated log file.
- I attached the backtrace in the case of a crash.