> -----Original Message----- > From: ffmpeg-devel [mailto:ffmpeg-devel-boun...@ffmpeg.org] On Behalf > Of Hendrik Leppkes > Sent: Wednesday, December 26, 2018 09:15 > To: FFmpeg development discussions and patches <ffmpeg- > de...@ffmpeg.org> > Subject: Re: [FFmpeg-devel] [PATCH, v3] lavc/hevc_parser: cope with more > leading_zero_8bits and update FATE > > On Wed, Dec 26, 2018 at 12:42 AM Michael Niedermayer > <mich...@niedermayer.cc> wrote: > > > > On Mon, Dec 10, 2018 at 06:23:54PM +0800, Linjie Fu wrote: > > > Given that leading_zero_8bits can be included many times at the > beginning > > > of a NAL unit, blindly taking the startcode as 3 bytes will leave 0x00 > > > in last frame and may lead to some warnings in parse_nal_units when s- > >flags > > > is set to PARSER_FLAG_COMPLETE_FRAMES. > > > > > > Modify to put all of the zeroes between two frames into the second > frame. > > > Modify the code to print the buf_size like in H264 and reduce the > duplication. > > > > > > Update the FATE checksum for fate-hevc-bsf-mp4toannexb: > > > The ref output has redundant 0x00 at the end of the SUFFIX_SEI: > > > { 50 01 84 31 00 19 39 77 d0 7b 3f bd 1e 09 38 9a 79 41 > > > c0 16 11 da 18 aa 0a db 2b 19 fa 47 3f 0f 67 4a 91 9c a1 > > > 12 72 67 d6 f0 8f 66 ee 95 f9 e2 b9 ba 23 9a e8 80 00 } > > > > > > To verify the output of FATE: > > > ffmpeg -i hevc-conformance/WPP_A_ericsson_MAIN10_2.bit -c copy - > flags \ > > > +bitexact hevc-mp4.mov > > > ffmpeg -i hevc-mp4.mov -c:v copy -fflags +bitexact -f hevc hevc.out > > > > > > Signed-off-by: Linjie Fu <linjie...@intel.com> > > > --- > > > [v2]: Update FATE checksum. > > > [v3]: Cope with more leading_zero_8bits cases. > > > > > > libavcodec/hevc_parser.c | 14 +++++++++----- > > > tests/fate/hevc.mak | 2 +- > > > 2 files changed, 10 insertions(+), 6 deletions(-) > > > > > > diff --git a/libavcodec/hevc_parser.c b/libavcodec/hevc_parser.c > > > index 369d1338d0..62100ac654 100644 > > > --- a/libavcodec/hevc_parser.c > > > +++ b/libavcodec/hevc_parser.c > > > @@ -239,7 +239,7 @@ static int parse_nal_units(AVCodecParserContext > *s, const uint8_t *buf, > > > } > > > } > > > /* didn't find a picture! */ > > > - av_log(avctx, AV_LOG_ERROR, "missing picture in access unit\n"); > > > + av_log(avctx, AV_LOG_ERROR, "missing picture in access unit with > size %d\n", buf_size); > > > return -1; > > > > this should ne in a seperate patch > > > > > > > } > > > > > > @@ -267,8 +267,7 @@ static int > hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf, > > > if ((nut >= HEVC_NAL_VPS && nut <= HEVC_NAL_EOB_NUT) || nut > == HEVC_NAL_SEI_PREFIX || > > > (nut >= 41 && nut <= 44) || (nut >= 48 && nut <= 55)) { > > > if (pc->frame_start_found) { > > > - pc->frame_start_found = 0; > > > - return i - 5; > > > + goto found; > > > } > > > } else if (nut <= HEVC_NAL_RASL_R || > > > (nut >= HEVC_NAL_BLA_W_LP && nut <= > HEVC_NAL_CRA_NUT)) { > > > @@ -277,14 +276,19 @@ static int > hevc_find_frame_end(AVCodecParserContext *s, const uint8_t *buf, > > > if (!pc->frame_start_found) { > > > pc->frame_start_found = 1; > > > } else { // First slice of next frame found > > > - pc->frame_start_found = 0; > > > - return i - 5; > > > + goto found; > > > } > > > } > > > } > > > } > > > > > > return END_NOT_FOUND; > > > + > > > +found: > > > + pc->frame_start_found = 0; > > > + while (i - 6 >= 0 && !buf[i - 6]) > > > + i--; > > > + return i - 5; > > > > I think this is incorrect > > a parser should produce the same output independant on how the input is > cut > > into bytsstream parts. But this would behave different depending on if the > > last 0 bytes are still in the current buffer > > > > Isnt it the parsers job to do just this cutting, or correct badly cut packets? > > - Hendrik
Paser will cache the bit stream in pc->buffer if END_NOT_FOUND in current buf. I think Michael's concern was some 0 bytes were stored in pc->buffer, and this patch could only cope with the 0 bytes in current buf but leave those 0 bytes stored in pc->buffer. If so, is it make sense to find all the leading 0 bytes in pc->buffer and change the index to cut correctly after finding the frame end? --- Thanks, Linjie _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
