[vorbis-dev] vorbis.dll; bug in vorbis_dsp_clear?;mc support

[Dark Avenger]

Hi,

<p>| However, if you call the various vorbis_*_clear() functions incorrectly
| (in the wrong order, for example) various things can happen - usually
| just memory leaks, but other things might be possible. 

This is the order in the vorbis.dll:

 ogg_stream_clear( &pStream->os );
 vorbis_block_clear( &pStream->vb );
 vorbis_dsp_clear( &pStream->vd );
 vorbis_comment_clear(&pStream->vc);
 vorbis_info_clear(&pStream->vi);

with

typedef struct VB_STREAM_TAG
{
 ogg_sync_state  oy; // sync and verify incoming physical bitstream 
 ogg_stream_state os; // take physical pages, weld into a logical stream of packets 
 ogg_page   og; // one Ogg bitstream page.  Vorbis packets are inside 
 ogg_packet   op; // one raw packet of data for decode 
 vorbis_info   vi; // struct that stores all the static vorbis bitstream settings 
 vorbis_comment  vc; // struct that stores all the bitstream user comments 
 vorbis_dsp_state vd; // central working state for the packet->PCM decoder 
 vorbis_block  vb; // local working space for packet->PCM decode 
 OggVorbis_File  vf; // input file handle
 PVB_ALBUM_INFO  pvbAlbumInfo;
 BOOL    bFirstFrame;
} VB_STREAM,* PVB_STREAM;

| If you can show us your code (the bits using libvorbis, that is), we
| may be able to help you further. 

Well, it is on CVS (CDEXOS project), but I could also send you the modified version of the vorbis.dll, though my mods shouldn't touch anything critical. I just thought people won't like it if I attach anything here. [file is vorbisdll.c] I merged that CVS file with libvorbis RC3 code and getting this trouble. I also sent A.Faber my sources of the modded files (not latest, but there is not much change). Nevertheless I didn't get much replies from him.

HeadAC3he doesn't use libvorbis, as it is much too complicated for me. I use the vorbis.dll which has a lame_enc.dll like interface, which uses the libvorbis. So in fact you don't need sources from HeadAC3he to debug. (BTW, I tried to run just vbencopen and vbenclose, *without* actually doing any encoding and got that error).

BTW, could you by chance tell me what dwInfoMode is good for (in VB_CONFIG sturct)? You can set it to
#define VB_MODE_A 100
#define VB_MODE_B 200
#define VB_MODE_C 300
#define VB_MODE_D 400
#define VB_MODE_E 500

and I can't actually see where it is used.

| There are a couple of major things here - first is defining channel
| mappings. Right now, there's nothing to say "channel 0 is front-left, 
| 1 is front-right, 2 is centre", etc. So for useful multi-channel support,
| that has to be defined somehow - but we haven't decided exactly how
| to do that. 

I just wanted to ask for this, as esp for decoding purposes it it critical to know which channel belongs to which speaker.

| The second is making the encoder use the channel coupling features 
| intelligently for these mappings - right now, it only knows about
| stereo files (anything else is treated as a set of independent 
| channels) - this doesn't break anything, it just means that the bitrate
| is higher than it needs to be.

Gosh, I hoped it tried to at least use stereo coupling on 6ch files. Would it help if for the time being the possibility would be there to say, eg. use stereo coupling for L and R and for SL and SR, so that C and LFE are treated as independant channels? This is of course far from optimal, but I guess better then current situation.

Thx 4 your reply,

D A

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