[speex-dev] Speex test cases?

joel randolph voss jvoss at u.washington.edu
Mon Feb 10 18:57:03 PST 2003


> 2. I don't have a good source of wav data for testing. I've noticed that
> introducing bugs into speex (even gross ones like returning completely
> incorrect codebook entries) tends to, sometimes subtly, degrade quality
> instead of blowing up. Is there an existing set of source data - and
> maybe even a test harness that will do binary comparison, so I can avoid
> writing one?

I don't have answers to 1 or 3, but on the issue of good test data, I've
been doing a bunch of testing. My best source of test data is System Shock
2, the video game. It includes 177 MB (4.3 hours) of speech WAV files in
16kHz IMA ADPCM format by various types of voices (male, female, noisy,
sharp, robotic, organic). Using a shell script and sox, I was able to
compress it down to 17 MB using 16 kHz wideband, variable bit rate,
quality 8 with release candidate 1. It definately isn't lossless, but
it's very good. If you'd like a few of these wav files to test (100k-300k
each), I can put a few on my web server.

My second source of data is my own microphone. Using sox, and a good
topic, I can rant for hours. sox can either save to wav, au, GSM,
SPHERE, IMA ADPCM, u-law, A-law, or other more established codec or it
can pipe it to speexenc. The script I made for on-the-fly compression is:

  sox -t ossdsp -r 8000 -b -s -c 1 /dev/dsp -t wav -r 8000 -s - | \
  speexenc -n --quality 8 - test.spx

You can replace 8000 with 16000 or 32000 and n with w or u to test
wideband and ultra-wideband.
And to save a lossless copy in wave format to compare, simply:

  sox -t ossdsp -r 8000 -b -s -c 1 /dev/dsp test.wav
  speexenc -n --quality 8 test.wav test.spx

Hope it's a bit of help on the testing side. My preliminary assessment of
Speex is: sweet. If you need someone to test specific things, I would be
happy to. While my coding knowledge is more at the application level
(programming 3d games and user apps specifically), I'd like to help if I
can. I plan to use Speex in the near future, so I'd like to help make
it better.

Btw, has anyone else noticed that the Speex XMMS plugin is missing? While
speexdec works well, I'd kinda like to use XMMS.

Best Regards,
Joel R. Voss

<p>--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'speex-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.

More information about the Speex-dev mailing list