| Message ID | 20231004225921.30287-3-michael@niedermayer.cc |
|---|---|
| State | New |
| Headers | show |
| Series | [FFmpeg-devel,1/4] avcodec/jpeg2000dec: Check image offset | expand |
| Context | Check | Description |
|---|---|---|
| yinshiyou/make_loongarch64 | success | Make finished |
| yinshiyou/make_fate_loongarch64 | success | Make fate finished |
> -----Original Message----- > From: ffmpeg-devel <ffmpeg-devel-bounces@ffmpeg.org> On Behalf Of > Michael Niedermayer > Sent: czwartek, 5 października 2023 00:59 > To: FFmpeg development discussions and patches <ffmpeg-devel@ffmpeg.org> > Subject: [FFmpeg-devel] [PATCH 3/4] avcodec/evc_parse: remove pow() and > log2() > > The use of float based functions is both unneeded and wrong due to > unpredictable rounding > > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > --- > libavcodec/evc_parse.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > diff --git a/libavcodec/evc_parse.c b/libavcodec/evc_parse.c index > 5ab33166cf3..20b6849041a 100644 > --- a/libavcodec/evc_parse.c > +++ b/libavcodec/evc_parse.c > @@ -176,7 +176,8 @@ int ff_evc_derive_poc(const EVCParamSets *ps, const > EVCParserSliceHeader *sh, > poc->PicOrderCntVal = 0; > poc->DocOffset = -1; > } else { > - int SubGopLength = (int)pow(2.0, sps->log2_sub_gop_length); > + int SubGopLength = 1 << sps->log2_sub_gop_length; > + > if (tid == 0) { > poc->PicOrderCntVal = poc->prevPicOrderCntVal + SubGopLength; > poc->DocOffset = 0; > @@ -191,15 +192,16 @@ int ff_evc_derive_poc(const EVCParamSets *ps, const > EVCParserSliceHeader *sh, > poc->prevPicOrderCntVal += SubGopLength; > ExpectedTemporalId = 0; > } else > - ExpectedTemporalId = 1 + (int)log2(poc->DocOffset); > + ExpectedTemporalId = 1 + av_log2(poc->DocOffset); > + > while (tid != ExpectedTemporalId) { > poc->DocOffset = (poc->DocOffset + 1) % SubGopLength; > if (poc->DocOffset == 0) > ExpectedTemporalId = 0; > else > - ExpectedTemporalId = 1 + (int)log2(poc->DocOffset); > + ExpectedTemporalId = 1 + > + av_log2(poc->DocOffset); > } > - PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset + 1) / > (int)pow(2.0, tid) - 2)); > + PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset > + + 1) / (1 << tid) - 2)); > poc->PicOrderCntVal = poc->prevPicOrderCntVal + PocOffset; > } > } > -- > 2.17.1 > Reviewed. Looks good. It can be merged. > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://protect2.fireeye.com/v1/url?k=b3e7a91c-d29c0395-b3e62253- > 74fe48600034-766db145edef46dd&q=1&e=130227c8-f092-4124-aef7- > bcb9009528da&u=https%3A%2F%2Fffmpeg.org%2Fmailman%2Flistinfo%2Fffmp > eg-devel > > To unsubscribe, visit link above, or email ffmpeg-devel-request@ffmpeg.org > with subject "unsubscribe".
On Fri, Oct 27, 2023 at 10:15:49AM +0200, Dawid Kozinski/Multimedia (PLT) /SRPOL/Staff Engineer/Samsung Electronics wrote: > > > > > > -----Original Message----- > > From: ffmpeg-devel <ffmpeg-devel-bounces@ffmpeg.org> On Behalf Of > > Michael Niedermayer > > Sent: czwartek, 5 października 2023 00:59 > > To: FFmpeg development discussions and patches <ffmpeg-devel@ffmpeg.org> > > Subject: [FFmpeg-devel] [PATCH 3/4] avcodec/evc_parse: remove pow() and > > log2() > > > > The use of float based functions is both unneeded and wrong due to > > unpredictable rounding > > > > Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> > > --- > > libavcodec/evc_parse.c | 10 ++++++---- > > 1 file changed, 6 insertions(+), 4 deletions(-) > > > > diff --git a/libavcodec/evc_parse.c b/libavcodec/evc_parse.c index > > 5ab33166cf3..20b6849041a 100644 > > --- a/libavcodec/evc_parse.c > > +++ b/libavcodec/evc_parse.c > > @@ -176,7 +176,8 @@ int ff_evc_derive_poc(const EVCParamSets *ps, const > > EVCParserSliceHeader *sh, > > poc->PicOrderCntVal = 0; > > poc->DocOffset = -1; > > } else { > > - int SubGopLength = (int)pow(2.0, sps->log2_sub_gop_length); > > + int SubGopLength = 1 << sps->log2_sub_gop_length; > > + > > if (tid == 0) { > > poc->PicOrderCntVal = poc->prevPicOrderCntVal + > SubGopLength; > > poc->DocOffset = 0; > > @@ -191,15 +192,16 @@ int ff_evc_derive_poc(const EVCParamSets *ps, const > > EVCParserSliceHeader *sh, > > poc->prevPicOrderCntVal += SubGopLength; > > ExpectedTemporalId = 0; > > } else > > - ExpectedTemporalId = 1 + (int)log2(poc->DocOffset); > > + ExpectedTemporalId = 1 + av_log2(poc->DocOffset); > > + > > while (tid != ExpectedTemporalId) { > > poc->DocOffset = (poc->DocOffset + 1) % SubGopLength; > > if (poc->DocOffset == 0) > > ExpectedTemporalId = 0; > > else > > - ExpectedTemporalId = 1 + > (int)log2(poc->DocOffset); > > + ExpectedTemporalId = 1 + > > + av_log2(poc->DocOffset); > > } > > - PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset + > 1) / > > (int)pow(2.0, tid) - 2)); > > + PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset > > + + 1) / (1 << tid) - 2)); > > poc->PicOrderCntVal = poc->prevPicOrderCntVal + > PocOffset; > > } > > } > > -- > > 2.17.1 > > > Reviewed. Looks good. It can be merged. will apply thx [...]
diff --git a/libavcodec/evc_parse.c b/libavcodec/evc_parse.c index 5ab33166cf3..20b6849041a 100644 --- a/libavcodec/evc_parse.c +++ b/libavcodec/evc_parse.c @@ -176,7 +176,8 @@ int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh, poc->PicOrderCntVal = 0; poc->DocOffset = -1; } else { - int SubGopLength = (int)pow(2.0, sps->log2_sub_gop_length); + int SubGopLength = 1 << sps->log2_sub_gop_length; + if (tid == 0) { poc->PicOrderCntVal = poc->prevPicOrderCntVal + SubGopLength; poc->DocOffset = 0; @@ -191,15 +192,16 @@ int ff_evc_derive_poc(const EVCParamSets *ps, const EVCParserSliceHeader *sh, poc->prevPicOrderCntVal += SubGopLength; ExpectedTemporalId = 0; } else - ExpectedTemporalId = 1 + (int)log2(poc->DocOffset); + ExpectedTemporalId = 1 + av_log2(poc->DocOffset); + while (tid != ExpectedTemporalId) { poc->DocOffset = (poc->DocOffset + 1) % SubGopLength; if (poc->DocOffset == 0) ExpectedTemporalId = 0; else - ExpectedTemporalId = 1 + (int)log2(poc->DocOffset); + ExpectedTemporalId = 1 + av_log2(poc->DocOffset); } - PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset + 1) / (int)pow(2.0, tid) - 2)); + PocOffset = (int)(SubGopLength * ((2.0 * poc->DocOffset + 1) / (1 << tid) - 2)); poc->PicOrderCntVal = poc->prevPicOrderCntVal + PocOffset; } }
The use of float based functions is both unneeded and wrong due to unpredictable rounding Signed-off-by: Michael Niedermayer <michael@niedermayer.cc> --- libavcodec/evc_parse.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)