AVIStreamOpenFromFileA function (vfw.h)

Article
02/09/2023

The AVIStreamOpenFromFile function opens a single stream from a file.

Syntax

HRESULT AVIStreamOpenFromFileA(
  PAVISTREAM *ppavi,
  LPCSTR     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 which 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 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