[Swftools-common] Developer: swfdump, SoundFormat Nellymoser ASAO Codec

[Till Toenshoff]

When browsing through swfdump.c (swftools-2006-06-26-1305), I noticed its
sound-format recognition is not entirely in sync with the Flash
specifications. For adapting swfdump to correctly identify more
sound-formats, the following changes do the job:

1. Since Flash 6, a codec called "Nellymoser ASAO" can be used. 

swfdump.c - line 306, old:      int compression = (flags>>4)&3;
swfdump.c - line 306, new:      int compression = flags>>4;
//SoundFormat; unsigned 4 bit value

swfdump.c - line 314, insert:   else if(compression == 6) printf("ASAO ");
//Nellymoser ASAO Codec supported since Flash 6


2. There are two "uncompressed" sound formats

swfdump.c - line 314, insert: else if(compression == 3) printf("Raw (little
endian)");      //Yet another "raw" format


Source:
Adobe Systems Inc.; "Macromedia Flash (SWF) and Flash Video (FLV) File
Format Specification Version 8"

Hope this helps,
Till