[Vorbis] Bug in ogg123 playback of OggFLAC files?

[Josh Coalson]

--- Barry Bouwsma <bugs at remove-NOSPAM-to-reply.NOSPAM.dyndns.dk> wrote:
> I used a recent ogg123 to play back a FLAC file I had created,
> and saw it wasn't able to seek within the file.  So, I thought
> to myself, why not try out an OggFLAC file, so I created one,
> using `flac --ogg', rather than oggenc or something else.
> 
> That ogg123 wasn't able to recognize the file as something it
> should have been able to chew on.  So I dirtied myself in the
> source code and found the following:
> 
>   if (len >= 32 && memcmp(buf, "OggS", 4) == 0
>                 && memcmp(buf+28, "fLaC", 4) == 0)
>     return 1; /* Ogg FLAC */
> 
> Hmmm.  That's sorta like my fresh file from somewhat recent
> source, but not quite:
> 00000000  4f 67 67 53 00 02 00 00  00 00 00 00 00 00 3d 59 
> |OggS..........=Y|
> 00000010  81 7a 00 00 00 00 31 e3  96 a9 01 30 46 4c 41 43 
> |.z....1....0FLAC|
> 00000020  01 00 66 4c 61 43 00 00  00 22 12 00 12 00 00 00 
> |..fLaC..."......|
> 
> Should the second line from the above code be a comparison
> against the string "FLAC" instead, or should the "fLaC"
> comparison be at position 34?
> 
> Changing the code to compare with "FLAC" results in a
> binary that can play my OggFLAC file, whee.  But I still
> can't seek.  The reason became clear when looking further
> through the code...
>   return 0;  /* No seeking at this time */
> Whoops, bummer.
> 
> Out of curiosity, how easy should it be to implement
> seeking within an OggFLAC file, as opposed to a plain
> ordinary FLAC file?

seeking was not supporting in libOggFLAC until FLAC 1.1.1

also in FLAC 1.1.1 is the first official (i.e. correct)
FLAC->Ogg mapping.  for more info about the history of it
see

  http://flac.sourceforge.net/ogg_mapping.html

that might explain some of the problems.

Josh



		
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