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View Full Version : Mp4box changes resolution when using chroma 444


codexredestemp
13th February 2016, 13:06
Hello.
Seems like there is a problem when muxing .264 files to .mp4 if the original .264 video uses chroma 4:4:4 (8 or 10 bit).

I have a video of 1000x800 resolution uncompressed .avi bgr24 and I did some tests:

.avi to .264 commands after pass 1:

x26410.exe ^
--pass 2 ^
--profile high444 ^
--preset slow ^
--output-csp i444 ^
--range pc ^
--fps 30 ^
--sar 1:1 ^
--stats "C:\testshit.stats" ^
--bitrate 6000 ^
--output testshit44410bit.264 "C:\testshit.avi"

Using x264 (8 or 10 bit) and using profile (high or high10) and using --output-csp i420:
- .264 video -> no problem
-muxing it with Mp4box -> no problem

Using x264 (8 or 10 bit) and using profile high444 and using --output-csp i444:
- .264 video -> no problem
-muxing it with Mp4box -> problem (changes width to 992 and, for example, MPC-HC reports resolution as "1000x800 (RdA 31:25)" 992x800.)

I have tested with mp4box version that comes with MP4BOXGUI 0606, mp4box rev563 and rev1180 using this commands:

-add "C:\testshit44410bit.264:fps=30.000:delay=0:name=testshit44410bit.264" -itags tool="My MP4Box GUI 0.6.0.6 <http://my-mp4box-gui.zymichost.com>" -brand mp42 -new "C:\testshit44410bit.mp4"

Latest Mediainfo and x264 18jan2016 version.

Hope someone can help.

sneaker_ger
13th February 2016, 13:21
Yes, the cropping calculation seems to be wrong when sub-sampling is not 4:2:0 and dimensions are not mod16.

If you want to make sure the developers see it create a ticket on their bug tracker:
https://github.com/gpac/gpac/issues

codexredestemp
15th February 2016, 11:54
Problem solved with Mp4box rev1192