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QSVENc 3.19 mbbrc broken

Open mikk9 opened this issue 6 years ago • 3 comments

QSVENc 3.19 broke the mbbrc functionality in both h264 and h265 @CBR/VBR. Also extbrc is used by default and I can't even disable it because the --no-extbrc command isn't supported by QSVEnc. So it's using extbrc no matter what which seems to be much worse than mbbrc. Furthermore the new adapt-ltr option doesn't seem to work, it does nothing to me.

mikk9 avatar Apr 24 '19 12:04 mikk9

Update:

  • enabling mbbrc enables extbrc, this function is swapped in QSVEnc 3.19
  • as a result mbbrc isn't working anymore for all modi which is a big downgrade for H265 because there is no LTR support
  • adapt-ltr works actually (CBR+VBR H264) when b-pyramid is disabled

mikk9 avatar Apr 26 '19 01:04 mikk9

MBBRC is working again, however adapt-ltr isn't working anymore in QSVEnc 3.20. I believe adapt-ltr also required extbrc because adapt-ltr in QSVEnc 3.19 only worked in combination with extbrc and extbrc isn't working either anymore with the swap fix.

mikk9 avatar Apr 26 '19 17:04 mikk9

This feature is available for the user defined BRC (ExtBRC) and will turn ON automatically when using the internal rate controller provided in the SDK (implicit) and when encoding parameter allow use of LTR. A new option mfxExtCodingOption3::ExtBrcAdaptiveLTR (on/off) is available in API 1.26 to control adaptive LTR. https://software.intel.com/en-us/articles/improve-encoding-efficiency-and-video-quality-with-adaptive-ltr

mikk9 avatar Apr 27 '19 01:04 mikk9