Re: dvb-t in Norway/NZ

On Friday 08 February 2008 10:14:24 Håkon Alstadheim wrote:
> The mplayer in svn has recently acquired its own version of faad2
> to decode sound, in the norwegian/nz dvb-t format. Work is in
> progress but there are still issues :-). Anyone who would like to
> share experiences on that, please speak up, or else I'll just lurk
> here. Just in case anyone is listening, here is why I felt the need
> to post:
>
> As you can see below, simply tuning and decoding seems to be too
> much for my system, even when  dumping both audio and video to dev
> null. This same system has no trouble playing analog tv, and the
> cpu utilization when running the command below is ~10%. "wa" in top
> is 0.0%. I guess I'll go to the -dev list and lurk there a bit, see
> if i see anyone who might appreciate my help in debugging.
>
> ---
> ===================================================================
>======= Opening audio decoder: [faad] AAC (MPEG2/4 Advanced Audio
> Coding)
>
> Unsupported LATM configuration: 3 programs/ 7 subframes, 5 layers,
> allstreams: 1
> FAAD: compressed input bitrate missing, assuming 128kbit/s!
> AUDIO: 48000 Hz, 2 ch, s16le, 128.0 kbit/8.33% (ratio:
> 16000->192000) Selected audio codec: [faad] afm: faad (FAAD AAC
> (MPEG-2/MPEG-4 Audio) decoder)
> ===================================================================
>======= AO: [null] 48000Hz 2ch s16le (2 bytes per sample)
> Starting playback...
>
> Unsupported LATM configuration: 3 programs/ 7 subframes, 5 layers,
> allstreams: 1
> FAAD: error: Maximum number of bitstream elements exceeded, trying
> to resync!
> VDec: vo config request - 720 x 576 (preferred colorspace: Planar
> YV12) VDec: using Planar YV12 as output csp (no 0)
> Movie-Aspect is 1.82:1 - prescaling to correct movie aspect.

does it play audio correctly at this point?


> VO: [null] 720x576 => 1048x576 Planar YV12
> [h264 @ 0x87980b0]B picture before any references, skipping??,?% 2
> 0 [h264 @ 0x87980b0]decode_slice_header error
> [h264 @ 0x87980b0]B picture before any references, skipping??,?% 3
> 0 [h264 @ 0x87980b0]decode_slice_header error
> A:21824.7 V:21819.3 A-V:  5.391 ct: -0.088  50/ 50 23%  0% 350.7%
> 50 0
>
>            ************************************************
>            **** Your system is too SLOW to play this!  ****
>            ************************************************
>
> Possible reasons, problems, workarounds:
> - Most common: broken/buggy _audio_ driver
>   - Try -ao sdl or use the OSS emulation of ALSA.
>   - Experiment with different values for -autosync, 30 is a good
> start. - Slow video output
>   - Try a different -vo driver (-vo help for a list) or try
> -framedrop! - Slow CPU
>   - Don't try to play a big DVD/DivX on a slow CPU! Try some of the
> lavdopts,
>     e.g. -vfm ffmpeg -lavdopts lowres=1:fast:skiploopfilter=all.
> - Broken file
>   - Try various combinations of -nobps -ni -forceidx -mc 0.
> - Slow media (NFS/SMB mounts, DVD, VCD etc)
>   - Try -cache 8192.
> - Are you using -cache to play a non-interleaved AVI file?
>   - Try -nocache.
> Read DOCS/HTML/en/video.html for tuning/speedup tips.
> If none of this helps you, read DOCS/HTML/en/bugreports.html.
>
> A:21827.9 V:21820.0 A-V:  7.852 ct:  0.036  81/ 81 21%  0% 309.3%
> 81 0
>
> MPlayer interrupted by signal 2 in module: decode_audio
> dvb_streaming_read, attempt N. 6 failed with errno 4 when reading
> 1432 bytes A:21828.1 V:21819.9 A-V:  8.177 ct:  0.040  82/ 82 21% 
> 0% 310.2% 82 0 Exiting... (Quit)
>

the best thing you can do is to collect a 10 minutes sample 
with -dumpstream and upload it to incoming.
I'll pipe it to mplayer and verify.
I suspect some issue with the main audio decoding loop 
(between ad_faad and faad itself, that decodes only 1 frame a time),
but I have to verify it