[FFmpeg-devel] [RFC][PATCH] ticks_per_frame / timebase

[Michael Niedermayer]

On Fri, Feb 27, 2009 at 10:59:15AM -0800, Baptiste Coudurier wrote:
> On 2/27/2009 3:54 AM, Michael Niedermayer wrote:
> > On Thu, Feb 26, 2009 at 07:01:15PM -0800, Baptiste Coudurier wrote:
> >> Michael Niedermayer wrote:
> >>> On Thu, Feb 26, 2009 at 03:30:22PM -0800, Baptiste Coudurier wrote:
> >>>> Baptiste Coudurier wrote:
> >>>>> Michael Niedermayer wrote:
> >>>>>> On Thu, Feb 26, 2009 at 02:46:36PM -0800, Baptiste Coudurier wrote:
> >>>>>>> Michael Niedermayer wrote:
> >>>>>>>> On Thu, Feb 26, 2009 at 02:18:41PM -0800, Baptiste Coudurier wrote:
> >>>>>>>>> Hi guys,
> >>>>>>>>>
> >>>>>>>>> Michael Niedermayer wrote:
> >>>>>>>>>> On Thu, Feb 26, 2009 at 10:05:28PM +0100, Ivan Schreter wrote:
> >>>>>>>>>>> Michael Niedermayer wrote:
> >>>>>>>>>>>> [...]
> >>>>>>>>>>>> also i think the reset of the sei vars should be in
> >>>>>>>>>>>> decode_nal_units()
> >>>>>>>>>>>> ...
> >>>>>>>>>>>>     if(!(s->flags2 & CODEC_FLAG2_CHUNKS)){
> >>>>>>>>>>>>         h->current_slice = 0;
> >>>>>>>>>>>>         if (!s->first_field)
> >>>>>>>>>>>>             s->current_picture_ptr= NULL;
> >>>>>>>>>>>>         <-----------------------here
> >>>>>>>>>>>>     }
> >>>>>>>>>>>>
> >>>>>>>>>>>> the reason is that just reseting at the end of a pic is "risky" if that 
> >>>>>>>>>>>> end
> >>>>>>>>>>>> isnt reached
> >>>>>>>>>>>>
> >>>>>>>>>>>>   
> >>>>>>>>>>> Like in the attached patch?
> >>>>>>>>>> yes, patch ok
> >>>>>>>>>>
> >>>>>>>>>> btw, if you want a svn write account, (and agree to the devel/svn policy
> >>>>>>>>>> and split patches a little more, this one should be
> >>>>>>>>>> factorizing the code and then seperately adding the new call)
> >>>>>>>>>> then send diego b. some username & password gpg encrypted
> >>>>>>>>>>
> >>>>>>>>> Applied both patches:
> >>>>>>>>>
> >>>>>>>>> ffmpeg -i h264.mp4 -vcodec copy test.mov
> >>>>>>>>>
> >>>>>>>>> Seems stream 1 codec frame rate differs from container frame rate: 12.50
> >>>>>>>>> (25/2) -> 25.00 (25/1)
> >>>>>>>>> Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'H264.mp4':
> >>>>>>>>>   Duration: 00:00:02.18, start: 0.000000, bitrate: 2245 kb/s
> >>>>>>>>>     Stream #0.0(eng): Audio: aac, 44100 Hz, stereo, s16
> >>>>>>>>>     Stream #0.1(eng): Video: h264, yuv420p, 720x576, 25 tbr, 25 tbn, 25 tbc
> >>>>>>>>> File 'test.mov' already exists. Overwrite ? [y/N] y
> >>>>>>>>> Output #0, mov, to 'test.mov':
> >>>>>>>>>     Stream #0.0(eng): Video: libx264, yuv420p, 720x576, q=2-31, 90k tbn,
> >>>>>>>>> 25 tbc
> >>>>>>>>>     Stream #0.1(eng): Audio: libfaac, 44100 Hz, stereo, s16, 64 kb/s
> >>>>>>>>>
> >>>>>>>>> Is this supposed to report 12.50 ?
> >>>>>>>> no, ive droped the hunk that messed with the printing in ffmpeg.c locally
> >>>>>>>> is the nonsense it prints the only problem? or are there other problems?
> >>>>>>>>
> >>>>>>> It seems ok, however it does not do the same for MPEG-2 when I stream copy:
> >>>>>>>
> >>>>>>> Seems stream 0 codec frame rate differs from container frame rate: 25.00
> >>>>>>> (50/2) -> 25.00 (25/1)
> >>>>>>> Input #0, mpeg, from 'PubMatrix.mpg':
> >>>>>>>   Duration: 00:00:24.26, start: 0.220000, bitrate: 11888 kb/s
> >>>>>>>     Stream #0.0[0x1e0]: Video: mpeg2video, yuv422p, 720x608 [PAR 1:1 DAR
> >>>>>>> 45:38], 11386 kb/s, 25 tbr, 90k tbn, 50 tbc
> >>>>>>>     Stream #0.1[0x1c0]: Audio: mp2, 48000 Hz, stereo, s16, 384 kb/s
> >>>>>>> File 'test.mov' already exists. Overwrite ? [y/N] y
> >>>>>>> Output #0, mov, to 'test.mov':
> >>>>>>>     Stream #0.0: Video: mpeg2video, yuv422p, 720x608 [PAR 1:1 DAR
> >>>>>>> 45:38], q=2-31, 11386 kb/s, 90k tbn, 50 tbc
> >>>>>>>     Stream #0.1: Audio: libfaac, 48000 Hz, stereo, s16, 64 kb/s
> >>>>>>> Stream mapping:
> >>>>>>>   Stream #0.0 -> #0.0
> >>>>>>>   Stream #0.1 -> #0.1
> >>>>>>>
> >>>>>>> In this case pkt->duration is 2 and timebase.den is 50, with H.264
> >>>>>>> pkt->duration is 1 and timebase.den is 25, is this normal ? Can't we get
> >>>>>>> 1 and 1/25 with MPEG-2 too ?
> >>>>>> yes, the following hunk does that:
> >>>>>> @@ -1750,9 +1751,10 @@
> >>>>>>              codec->bit_rate = icodec->bit_rate;
> >>>>>>              codec->extradata= icodec->extradata;
> >>>>>>              codec->extradata_size= icodec->extradata_size;
> >>>>>> -            if(av_q2d(icodec->time_base) > av_q2d(ist->st->time_base) && av_q2d(ist->st->time_base) < 1.0/1000)
> >>>>>> +            if(av_q2d(icodec->time_base)*icodec->ticks_per_frame > av_q2d(ist->st->time_base) && av_q2d(ist->st->time_base) < 1.0/1000){
> >>>>>>                  codec->time_base = icodec->time_base;
> >>>>>> -            else
> >>>>>> +                codec->time_base.num *= icodec->ticks_per_frame;
> >>>>>> +            }else
> >>>>>>                  codec->time_base = ist->st->time_base;
> >>>>>>              switch(codec->codec_type) {
> >>>>>>              case CODEC_TYPE_AUDIO:
> >>>>>>
> >>>>>>
> >>>>>> more issues left before i can commit it?
> >>>>> Nice.
> >>>>>
> >>>>> Please gimme 5 mins, I'm testing TS with H.264 and MPEG-2.
> >>>>>
> >>>> I don't see any regression for now.
> >>> good, ive applied it, if you find more regressions please tell me
> >>>
> >> I believe something may be wrong with the last frame:
> >>
> >> ffmpeg -y -i H264.mp4 test.mov
> > 
> > where can i find this file?
> 
> incoming on samples.ffmpeg.org, is it missing ?

ive looked for it in samples.mplayerhq.hu and with google ...

anyway the file works fine here, i suspect the vsync 2 fix today also
fixed it

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

Into a blind darkness they enter who follow after the Ignorance,
they as if into a greater darkness enter who devote themselves
to the Knowledge alone. -- Isha Upanishad
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20090227/2adb57e4/attachment.pgp>