Ville Rannikko wrote:
> Hi!
>
> The newest firmware for FF cards did not completely fix the AV desync problems
> for me.
Can you provide a sample recording where A/V sync fails with the current
firmware?
> According to information from Werner the problem happens when small
> video frames fill the decoder buffer with over 2 seconds of data. So I made
> this patch for dvbplayer.c to stop it from uploading more PES frames to decoder
> when STC/PTS difference is more than 2 seconds. This seems to fix the remaining
> problems for me, but I have not tested it much. The PTS/STC-code has been
> mostly taken from the dvb-subtitles plugin. Comments, please
The driver accepts as much data as the driver buffers can hold:
- max. 192 KByte video
- max. 64 KByte audio
The firmware requests data from the driver. The driver does not push
data to the firmware without request from the firmware.
Until now I do not understand how there could be any over/underflows
during normal operation.
> --- dvbplayer.c.orig 2007-01-31 18:21:42.000000000 +0200
> +++ dvbplayer.c 2007-01-31 18:35:36.000000000 +0200
> @@ -495,6 +495,51 @@
> }
> }
> if (p) {
> + if(playMode == pmPlay && pc > 13)
> + {
> + int64_t stc = -1;
> + int64_t pts = -1;
> +
> + if ( p[0] == 0x00 && p[1] == 0x00 && p[2] == 0x01)
> + {
> + if(p[7] & 0x80)
> + {
> + switch( p[3] )
> + {
> + case 0xE0 ... 0xEF: // video
> + case 0xC0 ... 0xDF: // audio
> + pts = (int64_t) (p[ 9] & 0x0E) << 29 ;
> + pts |= (int64_t) p[ 10] << 22 ;
> + pts |= (int64_t) (p[ 11] & 0xFE) << 14 ;
> + pts |= (int64_t) p[ 12] << 7 ;
> + pts |= (int64_t) (p[ 13] & 0xFE) >> 1 ;
> + }
> + }
> + }
> + if(pts != -1)
> + {
> + cDevice *pd = cDevice::PrimaryDevice();
> + if(pd)
> + {
> + stc = pd->GetSTC();
> + if(stc != 0)
> + {
> + if(pts & (int64_t)1<<32)
> + {
> + stc |= (int64_t)1<<32;
> + }
> + int64_t timeDiff = (pts-stc);
> + if (pts<stc)
> + {
> + timeDiff += (int64_t)1<<33;
> + }
> + timeDiff /= 90;
> + if(timeDiff > 2000)
> + cCondWait::SleepMs(timeDiff - 2000);
> + }
> + }
> + }
> + }
> int w = PlayPes(p, pc, playMode != pmPlay);
> if (w > 0) {
> p += w;
Hm, that patch does not look like a real bug fix to me. ;-)
It is a workaround which limits the total buffer capacity to max 2s.
I guess this works because it somehow triggers a resync in the firmware.
Anyway, fixes must be applied to the firmware or driver, not to VDR.
But let's analyse the problem first. We need a sample recording...
Oliver
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VDR Remote Plugin 0.3.9 available at
http://www.escape-edv.de/endriss/vdr/
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