AVIStreamOpenFromFileW function (vfw.h)
The AVIStreamOpenFromFile function opens a single stream from a file.
Syntax
HRESULT AVIStreamOpenFromFileW(
PAVISTREAM *ppavi,
LPCWSTR szFile,
DWORD fccType,
LONG lParam,
UINT mode,
CLSID *pclsidHandler
);
Parameters
ppavi
Pointer to a buffer that receives the new stream handle.
szFile
Null-terminated string containing the name of the file to open.
fccType
Four-character code indicating the type of stream to be opened. Zero indicates that any stream can be opened. The following definitions apply to the data commonly found in AVI streams:
| Value | Description |
|---|---|
| streamtypeAUDIO | Indicates an audio stream. |
| streamtypeMIDI | Indicates a MIDI stream. |
| streamtypeTEXT | Indicates a text stream. |
| streamtypeVIDEO | Indicates a video stream. |
lParam
Stream of the type specified in fccType to access. This parameter is zero-based; use zero to specify the first occurrence.
mode
Access mode to use when opening the file. This function can open only existing streams, so the OF_CREATE mode flag cannot be used. For more information about the available flags for the mode parameter, see the OpenFile function.
pclsidHandler
Pointer to a class identifier of the handler you want to use. If the value is NULL, the system chooses one from the registry based on the file extension or the file RIFF type.
Return value
Returns zero if successful or an error otherwise.
Remarks
This function calls the AVIFileOpen, AVIFileGetStream, and AVIFileRelease functions.
Note
The vfw.h header defines AVIStreamOpenFromFile as an alias that automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that is not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | vfw.h |
| Library | Vfw32.lib |
| DLL | Avifil32.dll |