[Speex-dev] Major internal changes, TI DSP build change

[Jim Crichton]

I rebuilt the TI DSP build for the C55 this morning, in order to add the 
window.c file to the TI project.  I encountered two problems:

1.  I got a compile error at line 410 in nb_celp.c, because this compiler 
will not allow variable declarations in the midst of executable code.  I 
fixed this by bracketing this code block:

line 410:
      {  /* Added */
      spx_word16_t *exc16_alias = (spx_word16_t*)st->exc;
--26 more lines, then--
         ol_gain = SHL32(EXTEND32(compute_rms16(exc16_alias, 
st->frameSize)),SIG_SHIFT);
#ifdef EPIC_48K
      }
#endif
      }  /* Added */

2:  The decoder is broken.  Running the Male.wav test file, I get all zeros 
out for the first 5 seconds, then 8 samples ranging from -2 to 2, and then 
all 0001 samples to the end of the file.  I got the same result feeding the 
encoded bits from Speex version 1.12.  Before I look into this further, I 
wanted to see if build 11147 was known to be broken.

This build is 8kbps, fixed point, no preprocessor/echo canceller.

On a separate topic, I want to propose a change to the TI C54x, C55x builds. 
Because these processors have 16 bit char size, there is some special code 
in bits.c to handle the packing.  As part of this, there is code to swap the 
byte order for each 16-bit char within speex_bits_write.  There is no such 
byte swapping in speex_bits_read_from, speex_bits_read_whole_bytes, or 
speex_bits_write_whole_bytes.  For consistency, the byte swapping should be 
done in all four places or in none of them.  In my present build, I have 
byte swapping in all four places, but it seems cleaner to take this out and 
leave it to the calling function to do the swapping if it is needed.  The 
demo builds are not affected, because the loopback application only uses 
speex_bits_write.

Since this affects the Speex interface (just for these targets), I though I 
should ask for feedback before sending a patch.  Does anybody care?

Note that speex_bits_read_from is broken in other ways (the length checking 
is wrong for the if BYTES_PER_CHAR=2), so bits.c needs to be updated either 
way.

Regards,

Jim Crichton

----- Original Message ----- 
From: "Jean-Marc Valin" <jean-marc.valin at usherbrooke.ca>
To: <speex-dev at xiph.org>
Sent: Tuesday, April 11, 2006 9:34 PM
Subject: [Speex-dev] Major internal changes


> Hi everyone,
>
> I've recently done some major internal changes in Speex aimed at
> reducing RAM (by nearly a factor of 2!) and improving quality of the
> fixed-point. In doing so, I might have accidently  broken a few things.
> I'd like to hear feedback on the current svn code to make sure I fix any
> regression before the next release. I'm already aware that
> --enable-vorbis-psy is broken and I'm working on fixing it.
>
> Jean-Marc
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