MntMPEG1SeqHdr Class Reference

Sequence header of an MPEG-1 video file. More...

#include <mnt_mpeg1_seq.h>

List of all members.

Public Member Functions
int	parse (BitParser *bp)
	Assuming the BitParser bp is pointing to the beginning of a sequence header in the bitstream, parse the header and initialize hdr.
int	find (BitParser *bp)
	Advance the BitParser bp to the beginning of a sequence header (by finding SEQ_START_CODE in the corrsponding bitstream).
int	dump (BitParser *inbp, BitParser *outbp)
	Dump a sequence header from inbp to outbp without interpreting it.
int	skip (BitParser *bp)
	Assuming that the input BitParser bp is at the beginning of a MPEG sequence header, skip the sequence header and advance bp's cursors to the beginning of GOP header immediately following the sequence header.
int	encode (BitParser *bp)
double	get_pic_rate ()
double	get_aspect_ratio ()
Public Attributes
short	width_
short	height_
short	mb_width_
short	mb_height_
int	bitrate_
int	vbv_buffer_size_
char	pel_aspect_ratio_
char	picture_rate_
char	constrained_
char	default_qt_
unsigned char	iqt_ [64]
unsigned char	niqt_ [64]
Static Private Attributes
static const int	RESERVE = -1
static const double	pel_aspect_ratio_table_ [16]
static const double	picture_rate_table_ [16]

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Detailed Description

Sequence header of an MPEG-1 video file.

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Member Function Documentation

int MntMPEG1SeqHdr::dump (  BitParser *  inbp, BitParser *  outbp )

Dump a sequence header from inbp to outbp without interpreting it. Inbp's cursor will be pointing to the beginning of the GOP header that follows the sequence header. Returns: Return the number of bytes dumped, or DVM_MPEG_INVALID_START_CODE if inbp is not pointing to a sequence header. Parameters: inbp  BitParser object to dump from outbp  BitParser object to dump to

int MntMPEG1SeqHdr::find (  BitParser *  bp  )

Advance the BitParser bp to the beginning of a sequence header (by finding SEQ_START_CODE in the corrsponding bitstream). Parameters: bp  BitParser object used to scan for sequence header. Returns: Returns the number of bytes skipped during the find. Returns DVM_MPEG_NOT_FOUND if it cannot find any header.

int MntMPEG1SeqHdr::parse (  BitParser *  bp  )

Assuming the BitParser bp is pointing to the beginning of a sequence header in the bitstream, parse the header and initialize hdr. Note: Header extension and user data are ignored. When this function completes, bp's cursor will be pointing to the beginning of the GOP header that follows the sequence header. Parameters: bp  BitParser object which contains the header to parse. Returns: Returns the number of bytes parsed, or DVM_MPEG_INVALID_START_CODE if bp is not pointing to a sequence header.

int MntMPEG1SeqHdr::skip (  BitParser *  bp  )

Assuming that the input BitParser bp is at the beginning of a MPEG sequence header, skip the sequence header and advance bp's cursors to the beginning of GOP header immediately following the sequence header. Parameters: bp  BitParser object which contains the header to skip. Returns: Return the number of bytes skipped, or DVM_MPEG_INVALID_START_CODE if bp is not pointing to a sequence header.

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Member Data Documentation

int MntMPEG1SeqHdr::bitrate_

In units of 400 bits/second

char MntMPEG1SeqHdr::constrained_

Boolean - true if a constrained param mpeg

char MntMPEG1SeqHdr::default_qt_

0 - both, 1 - iqt, 2 - niqt, 3 - none

short MntMPEG1SeqHdr::height_

height of each frame

unsigned char MntMPEG1SeqHdr::iqt_[64]

Intra quantization table - 64 elements

short MntMPEG1SeqHdr::mb_height_

height of each frame in macroblocks

short MntMPEG1SeqHdr::mb_width_

width of each frame in macroblocks

unsigned char MntMPEG1SeqHdr::niqt_[64]

Non intra quantization table

char MntMPEG1SeqHdr::pel_aspect_ratio_

Index to aspect ratio table

const double MntMPEG1SeqHdr::pel_aspect_ratio_table_ [static, private]

Initial value: { RESERVE, 1.000, 0.6735, 0.7031, 0.7615, 0.8055, 0.8437, 0.8935, 0.9375, 0.9815, 1.0255, 1.0695, 1.1250, 1.1575, 1.2015, RESERVE }

char MntMPEG1SeqHdr::picture_rate_

Index to picture rate table

const double MntMPEG1SeqHdr::picture_rate_table_ [static, private]

Initial value: { RESERVE, 23.976, 24, 25, 29.97, 30, 50, 59.94, 60, RESERVE, RESERVE, RESERVE, RESERVE, RESERVE, RESERVE, RESERVE }

int MntMPEG1SeqHdr::vbv_buffer_size_

Decoding verifier buffer size

short MntMPEG1SeqHdr::width_

width of each frame

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The documentation for this class was generated from the following files:

• mnt_mpeg1_seq.h
• mnt_mpeg1_seq.cc

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