I found that the subject for this v5 set of patches was wrong. I have posted the v6 with the correction.
> On Aug 1, 2024, at 10:58, WATANABE Osamu <owata...@es.takushoku-u.ac.jp> > wrote: > > According to the suggestions for v4, I have posted the patch set v5. > > It is confirmed that the decoder with v5 passes all the conformance testing > defined in ISO/IEC 15444-4. > > Best, > Osamu > > >> On Jul 31, 2024, at 6:39, Michael Niedermayer <mich...@niedermayer.cc> wrote: >> >> On Tue, Jul 30, 2024 at 10:22:37PM +0200, Tomas Hardin wrote: >>> fre 2024-07-26 klockan 23:29 +0200 skrev Michael Niedermayer: >>>> On Thu, Jul 25, 2024 at 05:06:04PM -0700, Pierre-Anthony Lemieux >>>> wrote: >>>>> On Thu, Jul 25, 2024 at 2:17?AM Tomas Hardin <g...@haerdin.se> >>>>> wrote: >>>>>> >>>>>> son 2024-07-21 klockan 14:07 +0900 skrev Pierre-Anthony Lemieux: >>>>>>> On Sat, Jul 20, 2024 at 5:12?PM Tomas Hardin <g...@haerdin.se> >>>>>>> wrote: >>>>>>>> >>>>>>>> tor 2024-07-18 klockan 23:10 +0900 skrev Pierre-Anthony >>>>>>>> Lemieux: >>>>>>>>> On Mon, Jul 15, 2024 at 10:33?PM Tomas Hardin >>>>>>>>> <g...@haerdin.se> >>>>>>>>> wrote: >>>>>>>>>> >>>>>>>>>> fre 2024-07-12 klockan 12:51 -0700 skrev Pierre-Anthony >>>>>>>>>> Lemieux: >>>>>>>>>>> On Thu, Jul 11, 2024 at 10:28?PM Tomas Hardin >>>>>>>>>>> <g...@haerdin.se> >>>>>>>>>>> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> + if (s->in_tile_headers == 1 && s->isHT >>>>>>>>>>>>> && >>>>>>>>>>>>> (!s- >>>>>>>>>>>>>> Ccap15_b11)) >>>>>>>>>>>>> + av_log(s->avctx, AV_LOG_WARNING, >>>>>>>>>>>>> "COD >>>>>>>>>>>>> marker >>>>>>>>>>>>> is >>>>>>>>>>>>> found in HOMOGENEOUS HT set\n"); >>>>>>>>>>>> >>>>>>>>>>>> How bad is this and the other markers being present >>>>>>>>>>>> in this >>>>>>>>>>>> case? >>>>>>>>>>> >>>>>>>>>>> At the very least, it means that signaling is >>>>>>>>>>> inconsistent >>>>>>>>>>> within >>>>>>>>>>> the >>>>>>>>>>> codestream since the standard states that: >>>>>>>>>>> """ >>>>>>>>>>> The HOMOGENEOUS set is the set of HTJ2K codestreams >>>>>>>>>>> where: >>>>>>>>>>> ? none of the functional marker segments, e.g., COD, >>>>>>>>>>> COC, >>>>>>>>>>> RGN, >>>>>>>>>>> QCD, >>>>>>>>>>> QCC, and POC, are present in any >>>>>>>>>>> tile-part header; and >>>>>>>>>>> ? no PPT marker segment is present. >>>>>>>>>>> """ >>>>>>>>>>> >>>>>>>>>>> The point of signalling that a codestream is >>>>>>>>>>> "HOMOGENEOUS" is >>>>>>>>>>> to >>>>>>>>>>> allow >>>>>>>>>>> decoders to configure themselves solely based on >>>>>>>>>>> information >>>>>>>>>>> retrieved >>>>>>>>>>> entirely from the main header. >>>>>>>>>>> >>>>>>>>>>> Since, AFAIK, FFMPEG does not rely on the HOMOGENEOUS >>>>>>>>>>> to >>>>>>>>>>> short- >>>>>>>>>>> circuit >>>>>>>>>>> configuration, incorrect HOMOGENEOUS signalling will >>>>>>>>>>> likely >>>>>>>>>>> not >>>>>>>>>>> impact >>>>>>>>>>> FFMPEG. >>>>>>>>>> >>>>>>>>>> It could happen that information in tile headers >>>>>>>>>> contradict >>>>>>>>>> information >>>>>>>>>> in the main header, right? In such a case it sounds like >>>>>>>>>> we >>>>>>>>>> can't >>>>>>>>>> be >>>>>>>>>> sure which decode is the correct one. >>>>>>>>> >>>>>>>>> Per the spec, the decoder uses the COD information in tile- >>>>>>>>> parts >>>>>>>>> over >>>>>>>>> the COD information in the header. >>>>>>>>> >>>>>>>>> The issue here is that a decoder, upon seeing HOMOGENEOUS, >>>>>>>>> simply >>>>>>>>> does >>>>>>>>> not bother with looking for COD information in tile-parts, >>>>>>>>> thereby >>>>>>>>> missing critical information. >>>>>>>> >>>>>>>> So it is actually perfectly legal? Then it seems this patch >>>>>>>> is >>>>>>>> wrong >>>>>>> >>>>>>> What is not "illegal": the HOMOGENEOUS flag being equal to true >>>>>>> *and* >>>>>>> having COD marker segments in tile-parts. >>>>>>> >>>>>>> This is what the patch detects. >>>>>>> >>>>>>> FFMPEG can decode such illegal codestream. Other decoders might >>>>>>> not. >>>>>>> >>>>>>> The question is: what should FFMPEG do? Should FFMPEG exit or >>>>>>> warn >>>>>>> and continue. >>>>>> >>>>>> If the spec allows it but it's perhaps unadviced then warning >>>>>> about it >>>>>> seems reasonable >>>>> >>>>> (I totally messed up my double negative. Repeat below. Sorry for >>>>> the confusion.) >>>>> >>>>> What is "illegal": the HOMOGENEOUS flag being equal to true *and* >>>>> having COD marker segments in tile-parts. >>>>> >>>>> This is what the patch detects. >>>>> >>>>> FFMPEG can decode such illegal codestream. Other decoders might >>>>> not. >>>>> >>>>> The question is: what should FFMPEG do? Should FFMPEG exit or warn >>>>> and continue. >>>> >>>> Does such a codestream actually exist ? I mean is this just a >>>> hypothetical case >>>> or something existing ? >>> >>> This is more to stem the stream before anything happens because we were >>> lax with parsing >> >> If such files dont exist then being picky makes sense >> >> thx >> >> [...] >> -- >> Michael GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB >> >> You can kill me, but you cannot change the truth. >> _______________________________________________ >> ffmpeg-devel mailing list >> ffmpeg-devel@ffmpeg.org >> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel >> >> To unsubscribe, visit link above, or email >> ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > > > _______________________________________________ > ffmpeg-devel mailing list > ffmpeg-devel@ffmpeg.org > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > To unsubscribe, visit link above, or email > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
