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Re: Reference files in the test suite

From: s p <sebpiq@gmail.com>
Date: Thu, 18 Jul 2013 12:47:28 +0400
Message-ID: <CAGKuoCUniad=cwPFo2HfKBL6NN-cfqWGr4864q_prVN_krScKg@mail.gmail.com>
To: Chris Lowis <Chris.Lowis@bbc.co.uk>
Cc: "public-audio@w3.org" <public-audio@w3.org>
I don't know if that can help, but I usually use Pure Data to generate test
.wav files.
It is very quick to prepare a patch, and that way you can control exactly
sample by sample what's in your sound file, which is kind of handy.
Here is a patch I have used for generating test sound files :


You can then just keep the patch somewhere as a documentation of how the
sound files were generated.

Sebastien Piquemal

2013/7/18 Chris Lowis <Chris.Lowis@bbc.co.uk>

> Hello,
> The test of the GainNode in our test suite currently looks like this:
> https://github.com/w3c/web-platform-tests/blob/master/webaudio/the-audio-api/the-gainnode-interface/gain-node-test.html
> It's based on the layout test for the same node in the Webkit[1]. In it we
> compare a generate buffer to a known good reference, stored as a wav file.
> At the moment, I've lifted the reference files from the webkit layout
> tests, but, from the point of view of the W3C tests, it isn't particularly
> transparent as to where the reference comes from. There's a few options
> - generate a reference using mathematical operations in the setup of the
> test in an ArrayBuffer
> - generate a reference using a third-party software as a wave file
> (perhaps using something like Sox[2]), and have a script to document how it
> is produced
> - keep the wav files from the webkit source and use that as our reference.
> I think my preference is for the first option, but I wonder if someone
> familiar with the layout tests in blink/webkit (Chris?) could comment? I'd
> guess the references in those tests are there to catch regressions, and are
> regenerated using the engine itself periodically?
> Cheers,
> Chris
> [1]
> https://github.com/WebKit/webkit/blob/master/LayoutTests/webaudio/gain.html
> [2] http://sox.sourceforge.net/
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Received on Thursday, 18 July 2013 08:47:55 UTC

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