Microsoft Audio Compression Manager API - Revision history

Multimedia Mike: typo

2014-09-27T18:06:27Z

typo

← Older revision		Revision as of 11:06, 27 September 2014
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	* Company: [[Microsoft]]		* Company: [[Microsoft]]

	Microsoft's Audio ~~Compress~~ Manager (ACM) API is the audio analog of their [[Microsoft Video For Windows API\|Video for Windows (VfW)]] API.		Microsoft's Audio Compression Manager (ACM) API is the audio analog of their [[Microsoft Video For Windows API\|Video for Windows (VfW)]] API.

	An ACM-compliant codec DLL exports a single function named DriverProc that takes a message and a few other parameters. The messages specify an action that the decoder is to perform.		An ACM-compliant codec DLL exports a single function named DriverProc that takes a message and a few other parameters. The messages specify an action that the decoder is to perform.

Multimedia Mike: import basic API elements

2006-05-20T02:06:25Z

import basic API elements

← Older revision		Revision as of 19:06, 19 May 2006
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	Microsoft's Audio Compress Manager (ACM) API is the audio analog of their [[Microsoft Video For Windows API\|Video for Windows (VfW)]] API.		Microsoft's Audio Compress Manager (ACM) API is the audio analog of their [[Microsoft Video For Windows API\|Video for Windows (VfW)]] API.

			An ACM-compliant codec DLL exports a single function named DriverProc that takes a message and a few other parameters. The messages specify an action that the decoder is to perform.

			The DriverProc usually consists of a switch statement. The main target in reverse engineering the decoding algorithm is the ACMDM_STREAM_CONVERT message, 0x604F.

			The first parameter is the following structure:
			typedef struct _ACMDRVSTREAMINSTANCE
			{
			DWORD cbStruct; // 0x00
			PWAVEFORMATEX pwfxSrc; // 0x04
			PWAVEFORMATEX pwfxDst; // 0x08
			PWAVEFILTER pwfltr; // 0x0C
			DWORD dwCallback; // 0x10
			DWORD dwInstance; // 0x14
			DWORD fdwOpen; // 0x18
			DWORD fdwDriver; // 0x1C
			DWORD dwDriver; // 0x20
			HACMSTREAM has; // 0x24
			} ACMDRVSTREAMINSTANCE, *PACMDRVSTREAMINSTANCE;

			The second parameter is the following structure:
			typedef struct _ACMDRVSTREAMHEADER
			{
			DWORD cbStruct; // 0x00
			DWORD fdwStatus; // 0x04
			DWORD dwUser; // 0x08
			LPBYTE pbSrc; // 0x0C
			DWORD cbSrcLength; // 0x10
			DWORD cbSrcLengthUsed; // 0x14
			DWORD dwSrcUser; // 0x18
			LPBYTE pbDst; // 0x1C
			DWORD cbDstLength; // 0x20
			DWORD cbDstLengthUsed; // 0x24
			DWORD dwDstUser; // 0x28
			DWORD fdwConvert; // 0x2C
			PACMDRVSTREAMHEADER *padshNext; // 0x30
			DWORD fdwDriver; // 0x34
			DWORD dwDriver; // 0x38

			/* Internal fields for ACM */
			DWORD fdwPrepared; // 0x3C
			DWORD dwPrepared; // 0x40
			LPBYTE pbPreparedSrc; // 0x44
			DWORD cbPreparedSrcLength; // 0x48
			LPBYTE pbPreparedDst; // 0x4C
			DWORD cbPreparedDstLength; // 0x50
			} ACMDRVSTREAMHEADER;

	[[Category:Multimedia APIs]]		[[Category:Multimedia APIs]]

Multimedia Mike at 19:23, 5 February 2006

2006-02-05T19:23:02Z

New page

* Company: [[Microsoft]]

Microsoft's Audio Compress Manager (ACM) API is the audio analog of their [[Microsoft Video For Windows API|Video for Windows (VfW)]] API.

[[Category:Multimedia APIs]]