On Mon, 3 Aug 2015 14:18:04 +0200 Hendrik Leppkes <h.lepp...@gmail.com> wrote:
> Hey, > > after a discussion on IRC about the declining quality of the QSV > decoders, I decided to do actual tests and document the results, so we > can get these fixed. > > A lot of these issues are regressions from recent changes, and work > fine in the original qsv decoders merged from libav, so they should be > given extra attention. > > 1) > Content with frame size changes is not handled at all. > A change to a smaller frame size will result in image corruption, and > a change to a bigger frame size will cause decoding to fail entirely. > > Sample (large to small): > http://fate-suite.ffmpeg.org/h264/reinit-large_420_8-to-small_420_8.h264 > > In this case, as hardware buffers are re-used, the images after the > change to a smaller size result in showing parts of the old image and > the new smaller image in the top left corner instead. > > 2) > Seeking is broken. For some reason refactoring of the qsv decoders has > resulted in their flush functions to become void. Seeking using ffplay > and the qsv decoder results in serious playback disruption. > > 3) > AV_PIX_FMT_QSV output is no longer functional. Refactoring has removed > the ff_get_format call, which results in API users no longer being > able to select the QSV pix fmt. > > These 3 issues are regression from the original decoder, and should be > corrected before further decoders are merged. As additional code using > the common qsv may require further changes in the future, its best to > fix the common code before adding even more. > > I'll make sure to review future qsv patches more actively to hopefully > avoid big regressions like these in the future as well. I have a > system setup now to test qsv, so that should be easier in the future. That's pretty serious and should have never happened. I suggest that we don't merge patches until all reviewer's comments were addressed. (Apparently some were ignored in the past.) _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
