Wave and it’s Compression

The WAVE format is a subset of RIFF used for storing digital audio. Its form type is “WAVE“, and it requires two kinds of chunks:

1) The FMT chunk – contains sample rate, sample width etc. (META Data)
2) The Data chunk – contains the sample data (actual data)

WAVE can also contain any other chunk type allowed by RIFF, including LIST chunks, which are used to contain optional kinds of data such as the copyright date, author’s name, etc. Chunks can appear in any order.

The WAVE specification supports a number of different compression algorithms. The format tag entry in the fmt chunk indicates the type of compression used. A value of 1 indicates Pulse Code Modulation (PCM), which is a “straight,” or uncompressed encoding of the samples.

The WAVE file format is a subset of Microsoft’s RIFF specification for the storage of multimedia files. A RIFF file starts out with a file header followed by a sequence of data chunks. A WAVE file is often just a RIFF file with a single “WAVE” chunk which consists of two sub-chunks — a “fmt ” chunk specifying the data format and a “data” chunk containing the actual sample data. Call this form the “Canonical form”.

As an example, here are the opening 72 bytes of a WAVE file with bytes shown as hexadecimal numbers:

52 49 46 46 24 08 00 00 57 41 56 45 66 6d 74 20 10 00 00 00 01 00 02 00
22 56 00 00 88 58 01 00 04 00 10 00 64 61 74 61 00 08 00 00 00 00 00 00
24 17 1e f3 3c 13 3c 14 16 f9 18 f9 34 e7 23 a6 3c f2 24 f2 11 ce 1a 0d