Talk:WAV

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[edit] Type 350

Does anyone know what this codec type is, or where I could find out? Mr. Jones 10:07, 1 Jul 2004 (UTC)

[edit] Lossy/lossless

I'm confused, this article describes PCM as lossless whereas all other articles seem to describe it as lossy (Lossy data compression, List of codecs). --gb 08:31, Feb 16, 2005 (UTC)

Don't mix up PCM and ADPCM. The first is "lossless", but the latter can be lossy.

According to the article, PCM is also uncompressed (which is why it it lossless -_-). This would seem to indicate that ADPCM is compressed.

You could also store data lossy without using compression, e. g. if you have a format with floating point values instead of integers :o) — 91.4.31.52 20:13, 5 November 2006 (UTC)

Why would one want to "store data lossy without using compression" ? The loss that the article is about is loss whose consequence in the data (image, sound or whatever) is never desireable but may be considered tolerable as the price for the benefit of compacting the data. Floating point values just have smaller (finite and non-constant) quantising steps than integer values. (cuddlyable3) 84.210.139.189 19:53, 18 November 2006 (UTC)

32bit Floating point can easily cover all 16bit integer numbers without any quantization effects. Quite the contrary: 32 bit floating is able to cover integers up to 25 bit (signed). The definition of lossless can be stated as follows: If a certain number format is capable to represent the input format without quantization or similar the encoding process is lossless (i.e. if the input signal can be completely reconstructed from the encoded signal). This does not depend only on the number format but also on the input signal. This implies that for each input signal which has to be encoded an appropriate encoding must be found which can fully (non-destructively) cover the input number range. E.g. if the input signal has a dynamic of 8 bits, the signal can be encoded lossless using 8 bits PCM. Compression has nothing to do with it. Compression is per definition a lossless process. If something can be lossy than it is encoding. Take mp3 for instance: The encoding is based on psycho-acoustical models what can result in a data reduction which can be (to trade space for exactness) lossy. Once encoded, the output stream gets compressed by a runlength compression. This runlength compression is completely reversible and that's the reason why it's a compression. Please respect the simple statutes for editors of encyclopaedias: First get the knowledge, then write. Wikipedia does not profit when it spreads misinformation only because of some writing exercises of some self-exposers.Cls.nebadje 11:07, 8 February 2007 (UTC)