User:Halftheisland/EA AS4 - Revision history

Halftheisland: Blanked the page

2013-10-03T12:14:28Z

Blanked the page

Halftheisland at 11:01, 3 October 2013

2013-10-03T11:01:33Z

Halftheisland: Created page with "{{FormatInfo |formattype=electronic |subcat=Audio and Music |extensions={{ext|as4}} {{ext|asf}} }} == Description == AS4 / ASF files are an audio file format used in many vi..."

2013-09-27T16:01:45Z

Created page with "{{FormatInfo |formattype=electronic |subcat=Audio and Music |extensions={{ext|as4}} {{ext|asf}} }} == Description == AS4 / ASF files are an audio file format used in many vi..."

New page

{{FormatInfo
|formattype=electronic
|subcat=Audio and Music
|extensions={{ext|as4}} {{ext|asf}}
}}

== Description ==

AS4 / ASF files are an audio file format used in many video games created by Electronic Arts. Note that extensions other than those listed may be AS4 / ASF files as Electronic Arts often change file extensions for different games.

== Information ==

The basic structure of AS4 / ASF files is similar to that of [[RIFF]], with each file divided into blocks (although, unlike [[RIFF]], the format does not have a global file header).

Each block starts with a standard header:

<pre>
struct ASFBlockHeader
{
char szBlockID[4];
DWORD dwSize;
};
</pre>

Where:

* <pre>szBlockID</pre> gives the string ID for the block
* <pre>dwSize</pre> gives the size of the block (including the header) in bytes.

Each file then consists of a number of blocks, each of which are described below.

=== Header Block ===

=== Sound Data ===

== Software ==

* http://bim.km.ru/gap/

== Links ==

* http://www.extractor.ru/articles/electronic_arts_audio_file_formats_description

← Older revision		Revision as of 12:14, 3 October 2013
Line 1:		Line 1:
−	~~{{FormatInfo~~
−	~~\|formattype=electronic~~
−	~~\|subcat=Audio and Music~~
−	~~\|extensions={{ext\|as4}} {{ext\|asf}}~~
−	}}

−	~~== Description ==~~
−
−	AS4 / ASF files are an audio file format used in many video games created by Electronic Arts. Note that extensions other than those listed may be AS4 / ASF files as Electronic Arts often change file extensions for different games.
−
−	~~== Information ==~~
−
−	~~The basic structure of AS4 / ASF files is similar to that of [[RIFF]], with each file divided into blocks (although, unlike [[RIFF]], the format does not have a global file header).~~
−
−	~~Each block starts with a standard header:~~
−
−	~~<pre>~~
−	~~struct ASFBlockHeader~~
−	{
−	~~char szBlockID[4];~~
−	~~DWORD dwSize;~~
−	};
−	~~</pre>~~
−
−	~~Where:~~
−
−	* ''szBlockID'' gives the string ID for the block
−	* ''dwSize'' gives the size of the block (including the header) in bytes.
−
−	~~Each file then consists of a number of blocks, each of which are described below.~~
−
−	~~=== Header Block ===~~
−
−	~~Block ID:'''1SNh'''~~
−
−	~~This is the first block in an ASF / AS4 file, describing the audio stream.~~
−
−	~~<pre>~~
−	~~struct EACSHeader~~
−	{
−	~~char szID[4];~~
−	~~DWORD dwSampleRate;~~
−	~~BYTE bBits;~~
−	~~BYTE bChannels;~~
−	~~BYTE bCompression;~~
−	~~BYTE bType;~~
−	~~DWORD dwNumSamples;~~
−	~~DWORD dwLoopStart;~~
−	~~DWORD dwLoopLength;~~
−	~~DWORD dwDataStart;~~
−	~~DWORD dwUnknown;~~
−	};
−	~~</pre>~~
−
−	* ''szID'' - the ID string, should always be "EACS"
−	* ''dwSampleRate'' - the sample rate for the file
−	* ''bBits'' - the resolution of the decompressed sound data, divided by 8 (i.e. 1 = 8-bit, 2 = 16-bit)
−	* ''bChannels'' - the number of channels. There are only two options: 1 for mono, 2 for stereo
−	* ''bCompression'' - if this is equal to 0x00, the audio data consists of signed 8 or 16-bit [[PCM]]. If it is equal to 0x02, the audio data consists of compressed [[IMA ADPCM]]
−
−	~~=== Sound Data ===~~
−
−	~~== Software ==~~
−
−	* http://bim.km.ru/gap/
−
−	~~== Links ==~~
−
−	* http://www.extractor.ru/articles/electronic_arts_audio_file_formats_description

@@ Line 25: / Line 25: @@
 Where:
-* <pre>szBlockID</pre> gives the string ID for the block
+* ''szBlockID'' gives the string ID for the block
-* <pre>dwSize</pre> gives the size of the block (including the header) in bytes.
+* ''dwSize'' gives the size of the block (including the header) in bytes.
 Each file then consists of a number of blocks, each of which are described below.
 === Header Block ===
 === Sound Data ===