[FFmpeg-devel] QSV Decoding - Issues and Regressions

Ivan Uskov ivan.uskov at nablet.com
Mon Aug 3 22:50:58 CEST 2015

Hello Ronald,

Monday, August 3, 2015, 11:37:22 PM, you wrote:

RSB> On Mon, Aug 3, 2015 at 3:25 PM, Ivan Uskov <ivan.uskov at nablet.com> wrote:

>> By the way, about old implementation which "worked fine".
>> It just did drop all buffered frames at decoder re-init on new
>> sequence header, there is nice comment inside old qsvdec_h264.c:
>> /* TODO: flush delayed frames on reinit */

RSB> Each AVCodec has a flush function which should do this. So as you
RSB> suggested, you need a flushing state which means you will output "old"
RSB> frames while consuming new frames and caching them internally in some way.
RSB> Then, when the decoder is flushed (either because flush was called, or
RSB> because all old cached frames have been returned), you can use all queued
RSB> packets to reinit the hw and start outputing frames right away.
Thank you for suggestion but unfortunately AVCodec::flush is useless
for this issue. The AVCodec::flush intended to *drop* decoded frames
and reset decoder before seeking and it calls by module outside of decoder.
My task is keep all frames without losing and decoder initiates
"flushing" by itself. So it is different kind of "flush".

Best regards,
 Ivan                            mailto:ivan.uskov at nablet.com

More information about the ffmpeg-devel mailing list