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AVI - functions, types and macros

Handle the load of avi file. More...

Data Structures
struct	AVI_CHUNK
	A chunk of the avi file. More...
struct	AVI_INDEX
	All the index of the movie. More...
struct	AVI_INDEX_ENTRY
	Each index entry of the file. More...
struct	AVI_MAIN_HEADER
	Main header of the avi file. More...
struct	AVI_MOVIE
	AVI movie. More...
struct	AVI_STREAM
	Contain all the information necessary to handle a stream. More...
struct	AVI_STREAM_DATA
	Information about the aditional data for stream format. More...
struct	AVI_STREAM_FORMAT
	Information about the format of one stream of the file. More...
struct	AVI_STREAM_HEADER
	Stream header, with information about one stream of the file. More...
Defines
#define	FCC_RIFF   AL_ID('F', 'F', 'I', 'R')
	First code in the avi.
#define	FCC_AVI   AL_ID(' ', 'I', 'V', 'A')
	After 'RIFF', this is need to be a valid avi file.
#define	FCC_LIST   AL_ID('T', 'S', 'I', 'L')
	Start of the list of chunks.
#define	FCC_hdrl   AL_ID('l', 'r', 'd', 'h')
	Start the list of headers.
#define	FCC_avih   AL_ID('h', 'i', 'v', 'a')
	Main avi header.
#define	FCC_strl   AL_ID('l', 'r', 't', 's')
	List of stream informations.
#define	FCC_strh   AL_ID('h', 'r', 't', 's')
	Header of the stream.
#define	FCC_strf   AL_ID('f', 'r', 't', 's')
	Stream format.
#define	FCC_strd   AL_ID('d', 'r', 't', 's')
	Additional stream data (not used).
#define	FCC_movi   AL_ID('i', 'v', 'o', 'm')
	List of frames in the movie.
#define	FCC_idx1   AL_ID('1', 'x', 'd', 'i')
	Index of the movie.
#define	FCC_vids   AL_ID('s', 'd', 'i', 'v')
	Type of the stream of video.
#define	FCC_auds   AL_ID('s', 'd', 'u', 'a')
	Type of the stream of audio.
#define	FCC_JUNK   AL_ID('K', 'N', 'U', 'J')
	Just for align data.
#define	FCC_DIVX   AL_ID('x', 'v', 'i', 'd')
	FCC of DivX codec.
#define	FCC_XVID   AL_ID('d', 'i', 'v', 'x')
	FCC of XviD codec.
#define	FCC_DIVX_OTHER   AL_ID('f', 'v', 'i', 'd')
	One of my DivX movies has this codec.
Functions
AVI_MOVIE *	avi_open (const char *name)
	Opens the file name and verifies if it is a valid avi.
void	avi_destroy (AVI_MOVIE *avi)
	Frees the memory allocated and close the file.
AVI_CHUNK *	avi_chunk_read_header (AVI_MOVIE *avi)
	Reads the fcc, size and sub-type of the next chunk in the file.
AVI_CHUNK *	avi_chunk_read (AVI_MOVIE *avi)
	Reads the fcc, size, sub-type and data of the next chunk in the file.
void	avi_chunk_destroy (AVI_CHUNK *ac)
	Frees the memory allocated to a chunk.
void	avi_chunk_skip (AVI_MOVIE *avi)
	Skip the next chunk.
int	avi_read_frame_video (AVI_MOVIE *avi, int frame)
	Read a frame of video.

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Detailed Description

Handle the load of avi file.

You can use this module separately of MJpgAlleg, to implement your own AVI library.

Author:

Eduardo "Dudaskank"

Date:

• 19/09/2002 - Start
• 11/10/2002 - Start converting comments to doxygen style
• 03/11/2002 - Bug fixes for version 2.11 (new line at end of file)
• 02/04/2003 - Searching for a possible bug...
• 03/04/2003 - It's not really a bug, but an error in understanding the specs of avi. The length, in the stream header, is the numer of samples, not frames.

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Function Documentation

void avi_chunk_destroy (  AVI_CHUNK *    ac )

Frees the memory allocated to a chunk. The avi is a valid AVI_MOVIE pointer. Returns: Nothing See also: avi_chunk_read_header(), avi_chunk_read() Author: Eduardo "Dudaskank" Date: Created : 19/09/2002 Updated : -

AVI_CHUNK* avi_chunk_read (  AVI_MOVIE *    avi )

Reads the fcc, size, sub-type and data of the next chunk in the file. The subtype is read for RIFF and LIST fcc. The avi is a valid AVI_MOVIE pointer. Returns: Pointer to AVI_CHUNK struct if ok, NULL on error See also: avi_chunk_read_header(), avi_chunk_destroy(), avi_chunk_skip() Author: Eduardo "Dudaskank" Date: Created : 19/09/2002 Updated : -

AVI_CHUNK* avi_chunk_read_header (  AVI_MOVIE *    avi )

Reads the fcc, size and sub-type of the next chunk in the file. The subtype is read for RIFF and LIST fcc. The avi is a valid AVI_MOVIE pointer. Returns: Pointer to AVI_CHUNK struct if ok, NULL on error See also: avi_chunk_read(), avi_chunk_destroy(), avi_chunk_skip() Author: Eduardo "Dudaskank" Date: Created : 19/09/2002 Updated : -

void avi_chunk_skip (  AVI_MOVIE *    avi )

Skip the next chunk. The avi is a valid AVI_MOVIE pointer. Returns: Nothing See also: avi_chunk_read_header(), avi_chunk_read() Author: Eduardo "Dudaskank" Date: Created : 19/09/2002 Updated : -

void avi_destroy (  AVI_MOVIE *    avi )

Frees the memory allocated and close the file. The avi is a valid AVI_MOVIE pointer Returns: Nothing See also: avi_open() Author: Eduardo "Dudaskank" Date: Created : 19/09/2002 Updated : 22/10/2002

AVI_MOVIE* avi_open (  const char *    name )

Opens the file name and verifies if it is a valid avi. This function will see if it's a valid RIFF file, of type AVI, and will load the header of the avi, the stream info, the offset of movi list and the index of the file Returns: pointer to a AVI_MOVIE struct if ok, NULL on error See also: avi_destroy(), avi_chunk_read_header(), avi_chunk_read() Author: Eduardo "Dudaskank" Date: Created : 19/09/2002 Updated : 23/09/2002

int avi_read_frame_video (  AVI_MOVIE *    avi, int    frame )

Read a frame of video. Stores the data in the buffer of video stream and the size of frame in frame_size. The avi is a valid AVI_MOVIE pointer, and frame is the number of the frame to read. Returns: 0 is ok, non zero is error See also: avi_chunk_read_header(), avi_chunk_read() Author: Eduardo "Dudaskank" Date: Created : 23/09/2002 Updated : 22/10/2002

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