Microsoft Video For Windows API - Revision history

Shahriman at 09:52, 16 February 2012

2012-02-16T09:52:55Z

← Older revision		Revision as of 02:52, 16 February 2012
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	* [[Category_talk:Video_FourCCs\|Compiled list of VFW codecs ]]		* [[Category_talk:Video_FourCCs\|Compiled list of VFW codecs ]]

	Microsoft's Video for Windows (VfW) API uses a refreshingly simple API. A Windows dynamic link library (DLL) that conforms to the VfW API is expected to ~~expect~~ a single function with the following declaration:		Microsoft's Video for Windows (VfW) API uses a refreshingly simple API. A Windows dynamic link library (DLL) that conforms to the VfW API is expected to export a single function with the following declaration:

	LRESULT WINAPI DriverProc(		LRESULT WINAPI DriverProc(

Compn: link to my list of vfw codecs

2011-04-29T23:35:16Z

link to my list of vfw codecs

← Older revision		Revision as of 16:35, 29 April 2011
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	* Company: [[Microsoft]]		* Company: [[Microsoft]]
			* [[Category_talk:Video_FourCCs\|Compiled list of VFW codecs ]]

	Microsoft's Video for Windows (VfW) API uses a refreshingly simple API. A Windows dynamic link library (DLL) that conforms to the VfW API is expected to expect a single function with the following declaration:		Microsoft's Video for Windows (VfW) API uses a refreshingly simple API. A Windows dynamic link library (DLL) that conforms to the VfW API is expected to expect a single function with the following declaration:

Multimedia Mike at 19:20, 5 February 2006

2006-02-05T19:20:35Z

New page

* Company: [[Microsoft]]

Microsoft's Video for Windows (VfW) API uses a refreshingly simple API. A Windows dynamic link library (DLL) that conforms to the VfW API is expected to expect a single function with the following declaration:

LRESULT WINAPI DriverProc(
DWORD dwDriverId,
HDRVR hDriver,
UINT uMsg,
LPARAM lParam1,
LPARAM lParam2);

All parameters are 32 bits wide. The parameters are defined as follows:

* dwDriverId: A pointer to any private data that the codec needs to maintain between driver calls.
* hDriver: Unknown; may not be especially important.
* uMsg: This message parameter defines what operation DriverProc should perform on this particular call.
* lParam1: Operation-specific data field that varies depending on uMsg.
* lParam2: Operation-specific data field that varies depending on uMsg.

The DriverProc() function returns a 32-bit number indicating status as defined by the VfW API.

Other data structures:

typedef struct {
DWORD dwSize;
DWORD fccType;
DWORD fccHandler;
DWORD dwVersion;
DWORD dwFlags;
LRESULT dwError;
LPVOID pV1Reserved;
LPVOID pV2Reserved;
DWORD dnDevNode;
} ICOPEN;

typedef struct {
DWORD dwFlags;
LPBITMAPINFOHEADER lpbiInput;
LPVOID lpInput;
LPBITMAPINFOHEADER lpbiOutput;
LPVOID lpOutput;
DWORD ckid;
} ICDECOMPRESS;

driver primitives
0x0001 DRV_LOAD
0x0003 DRV_OPEN
0x0004 DRV_CLOSE
0x0006 DRV_FREE

driver return codes
0x0000 DRVCNF_CANCEL
0x0001 DRVCNF_OK
0x0002 DRVCNF_RESTART

driver messages
0x400A ICM_DECOMPRESS_GET_FORMAT
0x400B ICM_DECOMPRESS_QUERY
0x400C ICM_DECOMPRESS_BEGIN
0x400D ICM_DECOMPRESS
0x400E ICM_DECOMPRESS_END
0x401D ICM_DECOMPRESS_SET_PALETTE
0x401E ICM_DECOMPRESS_GET_PALETTE

references:
* Microsoft vfw.h API file
* [http://www.xvid.org XviD] source code

[[Category:Multimedia APIs]]