RealAudio atrc: Difference between revisions

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(Maxpol moved page RealAudio atrc to ATRAC3: Rename to reflect codec's original name instead of its clone.)
Tag: New redirect
 
m (Add Sony to the list of companies.)
 
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#REDIRECT [[ATRAC3]]
* FOURCC: atrc
* Company: [[Sony]], [[Real]]
* Samples: http://samples.mplayerhq.hu/real/AC-atrc/
 
Found in some old [[RealMedia]] files. The same as the [[ATRAC3]].
 
== Scrambling ==
 
In [[RealMedia]] files, the ATRAC3 bitstream is scrambled. To unscramble the stream, perform a XOR on every 32 bits in the frame. The hex value to XOR with is 0x537F6103.
 
== Extra data format ==
 
In [[RealMedia]] files, ATRAC3 extra data has the following format (big-endian order):
 
INT32 id, always 4
INT16 samples per frame, always 1024 * 2
INT16 delay, not used but always 0x88E
INT16 stereo coding mode, 2 - normal stereo, 0x12 - joint stereo
 
The length of this data is always 10 bytes.

Latest revision as of 06:40, 29 November 2018

Found in some old RealMedia files. The same as the ATRAC3.

Scrambling

In RealMedia files, the ATRAC3 bitstream is scrambled. To unscramble the stream, perform a XOR on every 32 bits in the frame. The hex value to XOR with is 0x537F6103.

Extra data format

In RealMedia files, ATRAC3 extra data has the following format (big-endian order):

INT32	id, always 4
INT16	samples per frame, always 1024 * 2
INT16	delay, not used but always 0x88E
INT16	stereo coding mode, 2 - normal stereo, 0x12 - joint stereo

The length of this data is always 10 bytes.