FFMpeg video decode quality setting is ingored

[dustinkerstein]

FFMPEGQUALITYDEC doesn't seem to be used on line 330 of gear360video.cmd resulting in very low quality jpeg extracted frames.

[ultramango]

Hi!

Thanks for the report, I'll try to reproduce this on my side.

L.

[ultramango]

Are we talking about -q:v 2 option? It works for me... have a look at this test code: https://gist.github.com/ultramango/5aefbc0655c530d8e971d4efc4ecc5ea - it will produce test_result.csv file showing relation between quality parameter and file size.

Could you provide more details? Try running the test script from the link. The only explanation I have is that your ffmpeg is built with "weird" options, but that's highly unlikely.

More plausible is that the source material itself is low quality. This can happen for quickly changing scenes or scenes with lots of details.

[dustinkerstein]

Yeah, I can still replicate this with a fresh ffmpeg build and the latest gear360 repo. It's not the output h264 quality setting, but the temporary jpeg frames that are being rendered at very low quality.

"%FFMPEGPATH%/ffmpeg.exe" -y -i %1 %FRAMESTEMPDIR%/%IMAGETMPLDEC%

[allstone]

yes, its low quality. Script just does not use higher quality setting. I have put it there manually and then it works.