Commit 59dfb394 authored by Gildas Bazin's avatar Gildas Bazin

* include/vlc_block_helper.h: new block_FindStartcodeFromOffset() function.

* modules/packetizer/mpegvideo.c: rewrote the packetizer to use the block helper functions.
parent dd92e7ef
......@@ -2,7 +2,7 @@
* vlc_block_helper.h: Helper functions for data blocks management.
*****************************************************************************
* Copyright (C) 2003 VideoLAN
* $Id: vlc_block_helper.h,v 1.5 2003/11/16 21:07:30 gbazin Exp $
* $Id: vlc_block_helper.h,v 1.6 2003/12/06 23:25:23 gbazin Exp $
*
* Authors: Gildas Bazin <gbazin@netcourrier.com>
*
......@@ -436,4 +436,72 @@ static inline int block_PeekOffsetBytes( block_bytestream_t *p_bytestream,
return VLC_SUCCESS;
}
static inline int block_FindStartcodeFromOffset(
block_bytestream_t *p_bytestream, int *pi_offset,
uint8_t *p_startcode, int i_startcode_length )
{
block_t *p_block, *p_block_backup = 0;
int i_size, i_offset, i_offset_backup = 0;
int i_caller_offset_backup = 0, i_match;
/* Find the right place */
i_size = *pi_offset + p_bytestream->i_offset;
for( p_block = p_bytestream->p_block;
p_block != NULL; p_block = p_block->p_next )
{
i_size -= p_block->i_buffer;
if( i_size < 0 ) break;
}
if( i_size >= 0 )
{
/* Not enough data, bail out */
return VLC_EGENERIC;
}
/* Begin the search.
* We first look for an occurence of the 1st startcode byte and
* if found, we do a more thorough check. */
i_size = p_block->i_buffer + i_size;
*pi_offset -= i_size;
i_match = 0;
for( ; p_block != NULL; p_block = p_block->p_next )
{
for( i_offset = i_size; i_offset < p_block->i_buffer; i_offset++ )
{
if( p_block->p_buffer[i_offset] == p_startcode[i_match] )
{
if( !i_match )
{
p_block_backup = p_block;
i_offset_backup = i_offset;
i_caller_offset_backup = *pi_offset;
}
if( i_match + 1 == i_startcode_length )
{
/* We have it */
*pi_offset += i_offset - i_match;
return VLC_SUCCESS;
}
i_match++;
}
else if ( i_match )
{
/* False positive */
p_block = p_block_backup;
i_offset = i_offset_backup;
*pi_offset = i_caller_offset_backup;
i_match = 0;
}
}
i_size = 0;
*pi_offset += i_offset;
}
return VLC_EGENERIC;
}
#endif /* VLC_BLOCK_HELPER_H */
/*****************************************************************************
* mpegvideo.c
* mpegvideo.c: parse and packetize an MPEG1/2 video stream
*****************************************************************************
* Copyright (C) 2001, 2002 VideoLAN
* $Id: mpegvideo.c,v 1.23 2003/11/27 22:44:50 massiot Exp $
* $Id: mpegvideo.c,v 1.24 2003/12/06 23:25:23 gbazin Exp $
*
* Authors: Laurent Aimar <fenrir@via.ecp.fr>
* Eric Petit <titer@videolan.org>
* Gildas Bazin <gbazin@netcourrier.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
......@@ -45,6 +46,8 @@
#include <vlc/decoder.h>
#include <vlc/input.h>
#include "vlc_block_helper.h"
/*****************************************************************************
* Module descriptor
*****************************************************************************/
......@@ -57,43 +60,40 @@ vlc_module_begin();
set_callbacks( Open, Close );
vlc_module_end();
/*****************************************************************************
* Local prototypes
*****************************************************************************/
static block_t *Packetize( decoder_t *, block_t ** );
static int mpgv_FindStartCode( uint8_t **pp_start, uint8_t *p_end );
static block_t *ParseMPEGBlock( decoder_t *, block_t * );
struct decoder_sys_t
{
/* sequence header and extention */
/*
* Input properties
*/
block_bytestream_t bytestream;
int i_state;
int i_offset;
uint8_t p_startcode[3];
/* Sequence header and extention */
block_t *p_seq;
block_t *p_ext;
/* current frame being building */
/* Current frame being built */
block_t *p_frame;
vlc_bool_t b_frame_slice;
vlc_bool_t b_frame_corrupted;
vlc_bool_t b_gop;
/* pts of current picture */
mtime_t i_pts;
mtime_t i_dts;
/* gathering buffer */
int i_buffer;
int i_buffer_size;
uint8_t *p_buffer;
uint8_t *p_start, *p_old;
/* */
/* Sequence properties */
int i_frame_rate;
int i_frame_rate_base;
vlc_bool_t b_seq_progressive;
vlc_bool_t b_low_delay;
int i_aspect_ratio_info;
/* */
/* Picture properties */
int i_temporal_ref;
int i_picture_type;
int i_picture_structure;
......@@ -101,14 +101,18 @@ struct decoder_sys_t
int i_repeat_first_field;
int i_progressive_frame;
/* */
int i_seq_old; /* How many picture from last seq */
/* */
mtime_t i_interpolated_dts;
mtime_t i_old_duration;
mtime_t i_last_ref_pts;
/* Number of pictues since last sequence header */
int i_seq_old;
};
enum {
STATE_NOSYNC,
STATE_NEXT_SYNC
};
/*****************************************************************************
......@@ -126,26 +130,25 @@ static int Open( vlc_object_t *p_this )
return VLC_EGENERIC;
}
es_format_Init( &p_dec->fmt_out, VIDEO_ES, VLC_FOURCC( 'm', 'p', 'g', 'v' ) );
es_format_Init( &p_dec->fmt_out, VIDEO_ES, VLC_FOURCC('m','p','g','v') );
p_dec->pf_packetize = Packetize;
p_dec->p_sys = p_sys = malloc( sizeof( decoder_sys_t ) );
/* Misc init */
p_sys->i_state = STATE_NOSYNC;
p_sys->bytestream = block_BytestreamInit( p_dec );
p_sys->p_startcode[0] = 0;
p_sys->p_startcode[1] = 0;
p_sys->p_startcode[2] = 1;
p_sys->i_offset = 0;
p_sys->p_seq = NULL;
p_sys->p_ext = NULL;
p_sys->p_frame = NULL;
p_sys->b_frame_slice = VLC_FALSE;
p_sys->b_frame_corrupted = VLC_FALSE;
p_sys->b_gop = VLC_FALSE;
p_sys->i_buffer = 0;
p_sys->i_buffer_size = 10000;
p_sys->p_buffer = malloc( p_sys->i_buffer_size );
p_sys->p_start = p_sys->p_buffer;
p_sys->p_old = NULL;
p_sys->i_dts = 0;
p_sys->i_pts = 0;
p_sys->i_dts = p_sys->i_pts = 0;
p_sys->i_frame_rate = 1;
p_sys->i_frame_rate_base = 1;
......@@ -175,6 +178,8 @@ static void Close( vlc_object_t *p_this )
decoder_t *p_dec = (decoder_t*)p_this;
decoder_sys_t *p_sys = p_dec->p_sys;
block_BytestreamRelease( &p_sys->bytestream );
if( p_sys->p_seq )
{
block_Release( p_sys->p_seq );
......@@ -185,9 +190,9 @@ static void Close( vlc_object_t *p_this )
}
if( p_sys->p_frame )
{
block_Release( p_sys->p_frame );
block_ChainRelease( p_sys->p_frame );
}
free( p_sys->p_buffer );
free( p_sys );
}
......@@ -197,323 +202,356 @@ static void Close( vlc_object_t *p_this )
static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
{
decoder_sys_t *p_sys = p_dec->p_sys;
block_t *p_chain_out = NULL;
block_t *p_block;
block_t *p_pic;
if( pp_block == NULL || *pp_block == NULL )
{
return NULL;
}
p_block = *pp_block;
*pp_block = NULL;
if( p_block->b_discontinuity )
if( (*pp_block)->b_discontinuity )
{
p_sys->b_frame_corrupted = VLC_TRUE;
p_sys->i_state = STATE_NOSYNC;
if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
p_sys->p_frame = NULL;
p_sys->b_frame_slice = VLC_FALSE;
}
/* Append data */
if( p_sys->i_buffer + p_block->i_buffer > p_sys->i_buffer_size )
{
uint8_t *p_buffer = p_sys->p_buffer;
p_sys->i_buffer_size += p_block->i_buffer + 1024;
p_sys->p_buffer = realloc( p_sys->p_buffer, p_sys->i_buffer_size );
block_BytestreamPush( &p_sys->bytestream, *pp_block );
if( p_sys->p_start )
{
p_sys->p_start = p_sys->p_start - p_buffer + p_sys->p_buffer;
}
if( p_sys->p_old )
while( 1 )
{
switch( p_sys->i_state )
{
p_sys->p_old = p_sys->p_old - p_buffer + p_sys->p_buffer;
}
}
memcpy( &p_sys->p_buffer[p_sys->i_buffer], p_block->p_buffer,
p_block->i_buffer );
p_sys->i_buffer += p_block->i_buffer;
case STATE_NOSYNC:
if( block_FindStartcodeFromOffset( &p_sys->bytestream,
&p_sys->i_offset, p_sys->p_startcode, 3 ) == VLC_SUCCESS )
{
p_sys->i_state = STATE_NEXT_SYNC;
}
if( p_sys->i_offset )
{
block_SkipBytes( &p_sys->bytestream, p_sys->i_offset );
p_sys->i_offset = 0;
block_BytestreamFlush( &p_sys->bytestream );
}
if( p_sys->i_buffer > 10*1000000 )
{
msg_Err( p_dec, "mmh reseting context" );
p_sys->i_buffer = 0;
}
if( p_sys->i_state != STATE_NEXT_SYNC )
{
/* Need more data */
return NULL;
}
/* Split data in block */
for( ;; )
{
if( mpgv_FindStartCode( &p_sys->p_start, &p_sys->p_buffer[p_sys->i_buffer] ) )
{
block_Release( p_block );
p_sys->i_offset = 1; /* To find next startcode */
case STATE_NEXT_SYNC:
/* TODO: If p_block == NULL, flush the buffer without checking the
* next sync word */
if( p_sys->p_seq == NULL )
/* Find the next startcode */
if( block_FindStartcodeFromOffset( &p_sys->bytestream,
&p_sys->i_offset, p_sys->p_startcode, 3 ) != VLC_SUCCESS )
{
block_ChainRelease( p_chain_out );
/* Need more data */
return NULL;
}
return p_chain_out;
}
if( p_sys->p_old )
{
/* Extract the data */
int i_frag = p_sys->p_start - p_sys->p_old;
block_t *p_frag = block_New( p_dec, i_frag );
/* Get the new fragment and set the pts/dts */
p_pic = block_New( p_dec, p_sys->i_offset );
p_pic->i_pts = p_sys->bytestream.p_block->i_pts;
p_pic->i_dts = p_sys->bytestream.p_block->i_dts;
memcpy( p_frag->p_buffer, p_sys->p_old, i_frag );
if( i_frag < p_sys->i_buffer )
block_GetBytes( &p_sys->bytestream, p_pic->p_buffer,
p_pic->i_buffer );
/* don't reuse the same timestamps several times */
if( p_pic->i_buffer >= 4 && p_pic->p_buffer[3] == 0x00 )
{
memmove( p_sys->p_buffer, &p_sys->p_buffer[i_frag],
p_sys->i_buffer - i_frag );
/* We have a picture start code */
p_sys->bytestream.p_block->i_pts = 0;
p_sys->bytestream.p_block->i_dts = 0;
}
p_sys->i_buffer -= i_frag;
p_sys->p_start -= i_frag;
p_sys->p_old -= i_frag;
if( p_sys->b_frame_slice && ( p_frag->p_buffer[3] == 0x00 || p_frag->p_buffer[3] > 0xaf ) )
{
/* We have a complete picture output it */
if( p_sys->p_seq == NULL )
{
msg_Dbg( p_dec, "waiting sequence start" );
block_ChainRelease( p_sys->p_frame );
}
else if( p_sys->i_dts <= 0 && p_sys->i_pts <= 0 && p_sys->i_interpolated_dts <= 0 )
{
msg_Dbg( p_dec, "need a starting pts/dts" );
block_ChainRelease( p_sys->p_frame );
}
else if( p_sys->b_frame_corrupted )
{
msg_Warn( p_dec, "trashing a corrupted picture" );
block_ChainRelease( p_sys->p_frame );
p_sys->b_frame_corrupted = VLC_FALSE;
}
else
{
block_t *p_pic = block_ChainGather( p_sys->p_frame );
mtime_t i_duration = (mtime_t)( 1000000 * p_sys->i_frame_rate_base / p_sys->i_frame_rate);
if( !p_sys->b_seq_progressive && p_sys->i_picture_structure != 0x03 )
{
i_duration /= 2;
}
if( p_sys->b_seq_progressive )
{
if( p_sys->i_top_field_first == 0 && p_sys->i_repeat_first_field == 1 )
{
i_duration *= 2;
}
else if( p_sys->i_top_field_first == 1 && p_sys->i_repeat_first_field == 1 )
{
i_duration *= 3;
}
}
else
{
if( p_sys->i_picture_structure == 0x03 )
{
if( p_sys->i_progressive_frame && p_sys->i_repeat_first_field )
{
i_duration += i_duration / 2;
}
}
}
if( p_sys->b_low_delay || p_sys->i_picture_type == 0x03 )
{
/* Trivial case (DTS == PTS) */
/* Correct interpolated dts when we receive a new pts/dts */
if( p_sys->i_pts > 0 ) p_sys->i_interpolated_dts = p_sys->i_pts;
if( p_sys->i_dts > 0 ) p_sys->i_interpolated_dts = p_sys->i_dts;
}
else
{
/* Correct interpolated dts when we receive a new pts/dts */
if( p_sys->i_last_ref_pts > 0 )
p_sys->i_interpolated_dts = p_sys->i_last_ref_pts;
if( p_sys->i_dts > 0 ) p_sys->i_interpolated_dts = p_sys->i_dts;
p_sys->i_last_ref_pts = p_sys->i_pts;
}
p_pic->i_dts = p_sys->i_interpolated_dts;
/* Set PTS only if I frame or come from stream */
if( p_sys->i_pts > 0 )
{
p_pic->i_pts = p_sys->i_pts;
}
else if( p_sys->i_picture_type == 0x03 )
{
p_pic->i_pts = p_pic->i_dts;
}
else
{
p_pic->i_pts = -1;
}
if( p_sys->b_low_delay || p_sys->i_picture_type == 0x03 )
{
/* Trivial case (DTS == PTS) */
p_sys->i_interpolated_dts += i_duration;
}
else
{
p_sys->i_interpolated_dts += p_sys->i_old_duration;
p_sys->i_old_duration = i_duration;
}
p_pic->i_length = p_sys->i_interpolated_dts - p_pic->i_dts;
//msg_Dbg( p_dec, "pic: type=%d dts=%lld pts-dts=%lld", p_sys->i_picture_type, p_pic->i_dts, p_pic->i_pts - p_pic->i_dts);
block_ChainAppend( &p_chain_out, p_pic );
p_sys->i_offset = 0;
}
/* Get picture if any */
if( !( p_pic = ParseMPEGBlock( p_dec, p_pic ) ) )
{
p_sys->i_state = STATE_NOSYNC;
break;
}
/* reset context */
p_sys->p_frame = NULL;
p_sys->b_frame_slice = VLC_FALSE;
p_sys->b_gop = VLC_FALSE;
p_sys->i_pts = 0;
p_sys->i_dts = 0;
/* We've just started the stream, wait for the first PTS.
* We discard here so we can still get the sequence header. */
if( p_sys->i_dts <= 0 && p_sys->i_pts <= 0 &&
p_sys->i_interpolated_dts <= 0 )
{
msg_Dbg( p_dec, "need a starting pts/dts" );
p_sys->i_state = STATE_NOSYNC;
block_Release( p_pic );
break;
}
if( p_frag->p_buffer[3] == 0xb8 )
/* So p_block doesn't get re-added several times */
*pp_block = block_BytestreamPop( &p_sys->bytestream );
p_sys->i_state = STATE_NOSYNC;
return p_pic;
}
}
}
/*****************************************************************************
* ParseMPEGBlock: Re-assemble fragments into a block containing a picture
*****************************************************************************/
static block_t *ParseMPEGBlock( decoder_t *p_dec, block_t *p_frag )
{
decoder_sys_t *p_sys = p_dec->p_sys;
block_t *p_pic = NULL;
/*
* Check if previous picture is finished
*/
if( ( p_sys->b_frame_slice &&
(p_frag->p_buffer[3] == 0x00 || p_frag->p_buffer[3] > 0xaf) ) &&
p_sys->p_seq == NULL )
{
/* We have a picture but without a sequence header we can't
* do anything */
msg_Dbg( p_dec, "waiting for sequence start" );
if( p_sys->p_frame ) block_ChainRelease( p_sys->p_frame );
p_sys->p_frame = NULL;
p_sys->b_frame_slice = VLC_FALSE;
}
else if( p_sys->b_frame_slice &&
(p_frag->p_buffer[3] == 0x00 || p_frag->p_buffer[3] > 0xaf) )
{
mtime_t i_duration;
p_pic = block_ChainGather( p_sys->p_frame );
i_duration = (mtime_t)( 1000000 * p_sys->i_frame_rate_base /
p_sys->i_frame_rate );
if( !p_sys->b_seq_progressive && p_sys->i_picture_structure != 0x03 )
{
i_duration /= 2;
}
if( p_sys->b_seq_progressive )
{
if( p_sys->i_top_field_first == 0 &&
p_sys->i_repeat_first_field == 1 )
{
if( p_sys->p_seq &&
p_sys->i_seq_old > p_sys->i_frame_rate/p_sys->i_frame_rate_base )
{
/* Usefull for mpeg1: repeat sequence header every second */
block_ChainAppend( &p_sys->p_frame,
block_Duplicate( p_sys->p_seq ) );
if( p_sys->p_ext )
{
block_ChainAppend( &p_sys->p_frame,
block_Duplicate( p_sys->p_ext ) );
}
p_sys->i_seq_old = 0;
}
p_sys->b_gop = VLC_TRUE;
i_duration *= 2;
}
else if( p_frag->p_buffer[3] == 0xb3 )
else if( p_sys->i_top_field_first == 1 &&
p_sys->i_repeat_first_field == 1 )
{
static const int code_to_frame_rate[16][2] =
{
{ 1, 1 }, /* invalid */
{ 24000, 1001 }, { 24, 1 }, { 25, 1 }, { 30000, 1001 },
{ 30, 1 }, { 50, 1 }, { 60000, 1001 }, { 60, 1 },
{ 1, 1 }, { 1, 1 }, { 1, 1 }, { 1, 1 }, /* invalid */
{ 1, 1 }, { 1, 1 }, { 1, 1 } /* invalid */
};
/* sequence header */
if( p_sys->p_seq )
{
block_Release( p_sys->p_seq );
}
if( p_sys->p_ext )
i_duration *= 3;
}
}
else
{
if( p_sys->i_picture_structure == 0x03 )
{
if( p_sys->i_progressive_frame && p_sys->i_repeat_first_field )
{
block_Release( p_sys->p_ext );
p_sys->p_ext = NULL;
i_duration += i_duration / 2;
}
p_sys->p_seq = block_Duplicate( p_frag );
p_sys->i_seq_old = 0;
}
}
p_dec->fmt_out.video.i_width = ( p_frag->p_buffer[4] << 4)|(p_frag->p_buffer[5] >> 4 );
p_dec->fmt_out.video.i_height= ( (p_frag->p_buffer[5]&0x0f) << 8 )|p_frag->p_buffer[6];
if( p_sys->b_low_delay || p_sys->i_picture_type == 0x03 )
{
/* Trivial case (DTS == PTS) */
/* Correct interpolated dts when we receive a new pts/dts */
if( p_sys->i_pts > 0 ) p_sys->i_interpolated_dts = p_sys->i_pts;
if( p_sys->i_dts > 0 ) p_sys->i_interpolated_dts = p_sys->i_dts;
}
else
{
/* Correct interpolated dts when we receive a new pts/dts */
if( p_sys->i_last_ref_pts > 0 )
p_sys->i_interpolated_dts = p_sys->i_last_ref_pts;
if( p_sys->i_dts > 0 ) p_sys->i_interpolated_dts = p_sys->i_dts;
p_sys->i_frame_rate = code_to_frame_rate[p_frag->p_buffer[7]&0x0f][0];
p_sys->i_frame_rate_base = code_to_frame_rate[p_frag->p_buffer[7]&0x0f][1];
p_sys->i_last_ref_pts = p_sys->i_pts;
}
p_pic->i_dts = p_sys->i_interpolated_dts;
p_sys->b_seq_progressive = VLC_TRUE;
p_sys->b_low_delay = VLC_TRUE;
/* Set PTS only if we have a B frame or if it comes from the stream */
if( p_sys->i_pts > 0 )
{
p_pic->i_pts = p_sys->i_pts;
}
else if( p_sys->i_picture_type == 0x03 )
{
p_pic->i_pts = p_pic->i_dts;
}
else
{
p_pic->i_pts = 0;
}
if( p_sys->b_low_delay || p_sys->i_picture_type == 0x03 )
{
/* Trivial case (DTS == PTS) */
p_sys->i_interpolated_dts += i_duration;
}
else
{
p_sys->i_interpolated_dts += p_sys->i_old_duration;
p_sys->i_old_duration = i_duration;
}
p_pic->i_length = p_sys->i_interpolated_dts - p_pic->i_dts;
#if 0
msg_Dbg( p_dec, "Size %dx%d fps=%.3f",
p_dec->fmt_out.video.i_width,
p_dec->fmt_out.video.i_height,
(float)p_sys->i_frame_rate / (float)p_sys->i_frame_rate_base );
msg_Dbg( p_dec, "pic: type=%d dts="I64Fd" pts-dts="I64Fd,
p_sys->i_picture_type, p_pic->i_dts, p_pic->i_pts - p_pic->i_dts);
#endif
}
else if( p_frag->p_buffer[3] == 0xb5 )
/* Reset context */
p_sys->p_frame = NULL;
p_sys->b_frame_slice = VLC_FALSE;
}
/*
* Check info of current fragment
*/
if( p_frag->p_buffer[3] == 0xb8 )
{
/* Group start code */
if( p_sys->p_seq &&
p_sys->i_seq_old > p_sys->i_frame_rate/p_sys->i_frame_rate_base )
{
/* Usefull for mpeg1: repeat sequence header every second */
block_ChainAppend( &p_sys->p_frame,
block_Duplicate( p_sys->p_seq ) );
if( p_sys->p_ext )
{
int i_type = p_frag->p_buffer[4] >> 4;
/* extention start code */
if( i_type == 0x01 )
{
/* sequence extention */
if( p_sys->p_ext)
{
block_Release( p_sys->p_ext );
}
p_sys->p_ext = block_Duplicate( p_frag );
if( p_frag->i_buffer >= 10 )
{
p_sys->b_seq_progressive = p_frag->p_buffer[5]&0x08 ? VLC_TRUE : VLC_FALSE;
p_sys->b_low_delay = p_frag->p_buffer[9]&0x80 ? VLC_TRUE : VLC_FALSE;
}
}
else if( i_type == 0x08 )
{
/* picture extention */
p_sys->i_picture_structure = p_frag->p_buffer[6]&0x03;
p_sys->i_top_field_first = p_frag->p_buffer[7] >> 7;
p_sys->i_repeat_first_field= (p_frag->p_buffer[7]>>1)&0x01;
p_sys->i_progressive_frame = p_frag->p_buffer[8] >> 7;
}
block_ChainAppend( &p_sys->p_frame,
block_Duplicate( p_sys->p_ext ) );
}
else if( p_frag->p_buffer[3] == 0x00 )
p_sys->i_seq_old = 0;
}
}
else if( p_frag->p_buffer[3] == 0xb3 && p_frag->i_buffer >= 8 )
{
/* Sequence header code */
static const int code_to_frame_rate[16][2] =
{
{ 1, 1 }, /* invalid */
{ 24000, 1001 }, { 24, 1 }, { 25, 1 }, { 30000, 1001 },
{ 30, 1 }, { 50, 1 }, { 60000, 1001 }, { 60, 1 },