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vlc/modules/packetizer/h264.c
Sigmund Augdal Helberg 40a8f62662 packetizer/h264.c: fix divition by zero for some streams
2005-04-23 22:37:22 +00:00

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/*****************************************************************************
* h264.c: h264/avc video packetizer
*****************************************************************************
* Copyright (C) 2001, 2002 VideoLAN
* $Id$
*
* Authors: Laurent Aimar <fenrir@via.ecp.fr>
* Eric Petit <titer@videolan.org>
* Gildas Bazin <gbazin@videolan.org>
*
* 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
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#include <stdlib.h> /* malloc(), free() */
#include <vlc/vlc.h>
#include <vlc/decoder.h>
#include <vlc/sout.h>
#include "vlc_block_helper.h"
#include "vlc_bits.h"
/*****************************************************************************
* Module descriptor
*****************************************************************************/
static int Open ( vlc_object_t * );
static void Close( vlc_object_t * );
vlc_module_begin();
set_category( CAT_SOUT );
set_subcategory( SUBCAT_SOUT_PACKETIZER );
set_description( _("H264 video packetizer") );
set_capability( "packetizer", 50 );
set_callbacks( Open, Close );
vlc_module_end();
/****************************************************************************
* Local prototypes
****************************************************************************/
static block_t *Packetize( decoder_t *, block_t ** );
static block_t *PacketizeAVC1( decoder_t *, block_t ** );
struct decoder_sys_t
{
block_bytestream_t bytestream;
int i_state;
int i_offset;
uint8_t startcode[4];
vlc_bool_t b_slice;
block_t *p_frame;
vlc_bool_t b_sps;
vlc_bool_t b_pps;
/* avcC data */
int i_avcC_length_size;
/* Useful values of the Sequence Parameter Set */
int i_log2_max_frame_num;
int b_frame_mbs_only;
/* Useful values of the Slice Header */
int i_nal_type;
int i_nal_ref_idc;
int i_idr_pic_id;
int i_frame_num;
};
enum
{
STATE_NOSYNC,
STATE_NEXT_SYNC,
};
enum nal_unit_type_e
{
NAL_UNKNOWN = 0,
NAL_SLICE = 1,
NAL_SLICE_DPA = 2,
NAL_SLICE_DPB = 3,
NAL_SLICE_DPC = 4,
NAL_SLICE_IDR = 5, /* ref_idc != 0 */
NAL_SEI = 6, /* ref_idc == 0 */
NAL_SPS = 7,
NAL_PPS = 8,
NAL_AU_DELIMITER= 9
/* ref_idc == 0 for 6,9,10,11,12 */
};
enum nal_priority_e
{
NAL_PRIORITY_DISPOSABLE = 0,
NAL_PRIORITY_LOW = 1,
NAL_PRIORITY_HIGH = 2,
NAL_PRIORITY_HIGHEST = 3,
};
static block_t *ParseNALBlock( decoder_t *, block_t * );
static block_t *nal_get_annexeb( decoder_t *, uint8_t *p, int );
/*****************************************************************************
* Open: probe the packetizer and return score
*****************************************************************************/
static int Open( vlc_object_t *p_this )
{
decoder_t *p_dec = (decoder_t*)p_this;
decoder_sys_t *p_sys;
if( p_dec->fmt_in.i_codec != VLC_FOURCC( 'h', '2', '6', '4') &&
p_dec->fmt_in.i_codec != VLC_FOURCC( 'H', '2', '6', '4') &&
p_dec->fmt_in.i_codec != VLC_FOURCC( 'V', 'S', 'S', 'H') &&
p_dec->fmt_in.i_codec != VLC_FOURCC( 'v', 's', 's', 'h') &&
( p_dec->fmt_in.i_codec != VLC_FOURCC( 'a', 'v', 'c', '1') ||
p_dec->fmt_in.i_extra < 7 ) )
{
return VLC_EGENERIC;
}
/* Allocate the memory needed to store the decoder's structure */
if( ( p_dec->p_sys = p_sys = malloc( sizeof(decoder_sys_t) ) ) == NULL )
{
msg_Err( p_dec, "out of memory" );
return VLC_EGENERIC;
}
p_sys->i_state = STATE_NOSYNC;
p_sys->i_offset = 0;
p_sys->startcode[0] = 0;
p_sys->startcode[1] = 0;
p_sys->startcode[2] = 0;
p_sys->startcode[3] = 1;
p_sys->bytestream = block_BytestreamInit( p_dec );
p_sys->b_slice = VLC_FALSE;
p_sys->p_frame = NULL;
p_sys->b_sps = VLC_FALSE;
p_sys->b_pps = VLC_FALSE;
p_sys->i_nal_type = -1;
p_sys->i_nal_ref_idc = -1;
p_sys->i_idr_pic_id = -1;
p_sys->i_frame_num = -1;
/* Setup properties */
es_format_Copy( &p_dec->fmt_out, &p_dec->fmt_in );
p_dec->fmt_out.i_codec = VLC_FOURCC( 'h', '2', '6', '4' );
/* FIXME: FFMPEG isn't happy at all if you leave this */
if( p_dec->fmt_out.i_extra ) free( p_dec->fmt_out.p_extra );
p_dec->fmt_out.i_extra = 0; p_dec->fmt_out.p_extra = 0;
if( p_dec->fmt_in.i_codec == VLC_FOURCC( 'a', 'v', 'c', '1' ) )
{
uint8_t *p = &((uint8_t*)p_dec->fmt_in.p_extra)[4];
int i_sps, i_pps;
int i;
/* Parse avcC */
p_sys->i_avcC_length_size = 1 + ((*p++)&0x03);
/* Read SPS */
i_sps = (*p++)&0x1f;
for( i = 0; i < i_sps; i++ )
{
int i_length = GetWBE( p );
block_t *p_sps = nal_get_annexeb( p_dec, p + 2, i_length );
ParseNALBlock( p_dec, p_sps );
p += 2 + i_length;
}
/* Read PPS */
i_pps = *p++;
for( i = 0; i < i_pps; i++ )
{
int i_length = GetWBE( p );
block_t *p_pps = nal_get_annexeb( p_dec, p + 2, i_length );
ParseNALBlock( p_dec, p_pps );
p += 2 + i_length;
}
msg_Dbg( p_dec, "avcC length size=%d sps=%d pps=%d",
p_sys->i_avcC_length_size, i_sps, i_pps );
/* Set callback */
p_dec->pf_packetize = PacketizeAVC1;
}
else
{
/* Set callback */
p_dec->pf_packetize = Packetize;
}
return VLC_SUCCESS;
}
/*****************************************************************************
* Close: clean up the packetizer
*****************************************************************************/
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 );
free( p_sys );
}
/****************************************************************************
* Packetize: the whole thing
****************************************************************************/
static block_t *Packetize( decoder_t *p_dec, block_t **pp_block )
{
decoder_sys_t *p_sys = p_dec->p_sys;
block_t *p_pic;
if( !pp_block || !*pp_block ) return NULL;
block_BytestreamPush( &p_sys->bytestream, *pp_block );
for( ;; )
{
switch( p_sys->i_state )
{
case STATE_NOSYNC:
if( block_FindStartcodeFromOffset( &p_sys->bytestream,
&p_sys->i_offset, p_sys->startcode+1, 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_state != STATE_NEXT_SYNC )
{
/* Need more data */
return NULL;
}
p_sys->i_offset = 1; /* To find next startcode */
case STATE_NEXT_SYNC:
/* Find the next startcode */
if( block_FindStartcodeFromOffset( &p_sys->bytestream,
&p_sys->i_offset, p_sys->startcode, 3 ) != VLC_SUCCESS)
{
if( block_FindStartcodeFromOffset( &p_sys->bytestream,
&p_sys->i_offset, p_sys->startcode+1, 3 ) !=
VLC_SUCCESS )
{
/* Need more data */
return NULL;
}
}
/* 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;
block_GetBytes( &p_sys->bytestream, p_pic->p_buffer,
p_pic->i_buffer );
p_sys->i_offset = 0;
/* Parse the NAL */
if( !( p_pic = ParseNALBlock( p_dec, p_pic ) ) )
{
p_sys->i_state = STATE_NOSYNC;
break;
}
#if 0
msg_Dbg( p_dec, "pts="I64Fd" dts="I64Fd,
p_pic->i_pts, p_pic->i_dts );
#endif
/* 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;
}
}
}
/****************************************************************************
* PacketizeAVC1: the whole thing
****************************************************************************/
static block_t *PacketizeAVC1( decoder_t *p_dec, block_t **pp_block )
{
decoder_sys_t *p_sys = p_dec->p_sys;
block_t *p_block;
block_t *p_ret = NULL;
uint8_t *p;
if( !pp_block || !*pp_block ) return NULL;
p_block = *pp_block;
*pp_block = NULL;
for( p = p_block->p_buffer; p < &p_block->p_buffer[p_block->i_buffer]; )
{
block_t *p_pic;
int i_size = 0;
int i;
for( i = 0; i < p_sys->i_avcC_length_size; i++ )
{
i_size = (i_size << 8) | (*p++);
}
if( i_size > 0 )
{
block_t *p_part = nal_get_annexeb( p_dec, p, i_size );
p_part->i_dts = p_block->i_dts;
p_part->i_pts = p_block->i_pts;
/* Parse the NAL */
if( ( p_pic = ParseNALBlock( p_dec, p_part ) ) )
{
block_ChainAppend( &p_ret, p_pic );
}
}
p += i_size;
}
return p_ret;
}
static block_t *nal_get_annexeb( decoder_t *p_dec, uint8_t *p, int i_size )
{
block_t *p_nal;
p_nal = block_New( p_dec, 3 + i_size );
/* Add start code */
p_nal->p_buffer[0] = 0x00;
p_nal->p_buffer[1] = 0x00;
p_nal->p_buffer[2] = 0x01;
/* Copy nalu */
memcpy( &p_nal->p_buffer[3], p, i_size );
return p_nal;
}
static void nal_get_decoded( uint8_t **pp_ret, int *pi_ret,
uint8_t *src, int i_src )
{
uint8_t *end = &src[i_src];
uint8_t *dst = malloc( i_src );
*pp_ret = dst;
while( src < end )
{
if( src < end - 3 && src[0] == 0x00 && src[1] == 0x00 &&
src[2] == 0x03 )
{
*dst++ = 0x00;
*dst++ = 0x00;
src += 3;
continue;
}
*dst++ = *src++;
}
*pi_ret = dst - *pp_ret;
}
static inline int bs_read_ue( bs_t *s )
{
int i = 0;
while( bs_read1( s ) == 0 && s->p < s->p_end && i < 32 )
{
i++;
}
return( ( 1 << i) - 1 + bs_read( s, i ) );
}
static inline int bs_read_se( bs_t *s )
{
int val = bs_read_ue( s );
return val&0x01 ? (val+1)/2 : -(val/2);
}
static block_t *ParseNALBlock( decoder_t *p_dec, block_t *p_frag )
{
decoder_sys_t *p_sys = p_dec->p_sys;
block_t *p_pic = NULL;
const int i_nal_ref_idc = (p_frag->p_buffer[3] >> 5)&0x03;
const int i_nal_type = p_frag->p_buffer[3]&0x1f;
#define OUTPUT \
do { \
p_pic = block_ChainGather( p_sys->p_frame ); \
p_pic->i_length = 0; /* FIXME */ \
\
p_sys->p_frame = NULL; \
p_sys->b_slice = VLC_FALSE; \
} while(0)
if( p_sys->b_slice && !p_sys->b_sps )
{
block_ChainRelease( p_sys->p_frame );
msg_Warn( p_dec, "waiting for SPS" );
/* Reset context */
p_sys->p_frame = NULL;
p_sys->b_slice = VLC_FALSE;
}
if( !p_sys->b_sps &&
i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
{
p_sys->b_slice = VLC_TRUE;
/* Fragment will be discarded later on */
}
else if( i_nal_type >= NAL_SLICE && i_nal_type <= NAL_SLICE_IDR )
{
uint8_t *dec;
int i_dec, i_first_mb, i_slice_type, i_frame_num, i_pic_flags = 0;
vlc_bool_t b_pic = VLC_FALSE;
bs_t s;
/* do not convert the whole frame */
nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[4],
__MIN( p_frag->i_buffer - 4, 60 ) );
bs_init( &s, dec, i_dec );
/* first_mb_in_slice */
i_first_mb = bs_read_ue( &s );
/* slice_type */
switch( (i_slice_type = bs_read_ue( &s )) )
{
case 0: case 5:
i_pic_flags = BLOCK_FLAG_TYPE_P;
break;
case 1: case 6:
i_pic_flags = BLOCK_FLAG_TYPE_B;
break;
case 2: case 7:
i_pic_flags = BLOCK_FLAG_TYPE_I;
break;
case 3: case 8: /* SP */
i_pic_flags = BLOCK_FLAG_TYPE_P;
break;
case 4: case 9:
i_pic_flags = BLOCK_FLAG_TYPE_I;
break;
}
/* pic_parameter_set_id */
bs_read_ue( &s );
/* frame_num */
i_frame_num = bs_read( &s, p_sys->i_log2_max_frame_num + 4 );
/* Detection of the first VCL NAL unit of a primary coded picture
* (cf. 7.4.1.2.4) */
if( i_frame_num != p_sys->i_frame_num ||
( (i_nal_ref_idc != p_sys->i_nal_ref_idc) &&
(!i_nal_ref_idc || !p_sys->i_nal_ref_idc) ) )
{
b_pic = VLC_TRUE;
}
p_sys->i_frame_num = i_frame_num;
p_sys->i_nal_ref_idc = i_nal_ref_idc;
if( !p_sys->b_frame_mbs_only )
{
/* field_pic_flag */
if( bs_read( &s, 1 ) )
{
/* bottom_field_flag */
bs_read( &s, 1 );
}
}
if( i_nal_type == NAL_SLICE_IDR )
{
/* id_pic_id */
int i_idr_pic_id = bs_read_ue( &s );
if( p_sys->i_nal_type != i_nal_type ) b_pic = VLC_TRUE;
if( p_sys->i_idr_pic_id != i_idr_pic_id ) b_pic = VLC_TRUE;
p_sys->i_idr_pic_id = i_idr_pic_id;
}
p_sys->i_nal_type = i_nal_type;
if( b_pic && p_sys->b_slice )
OUTPUT;
p_sys->b_slice = VLC_TRUE;
free( dec );
}
else if( i_nal_type == NAL_SPS )
{
uint8_t *dec;
int i_dec;
bs_t s;
int i_tmp;
if( !p_sys->b_sps )
msg_Dbg( p_dec, "found NAL_SPS" );
p_sys->b_sps = VLC_TRUE;
nal_get_decoded( &dec, &i_dec, &p_frag->p_buffer[4],
p_frag->i_buffer - 4 );
bs_init( &s, dec, i_dec );
/* Skip profile(8), constraint_set012, reserver(5), level(8) */
bs_skip( &s, 8 + 1+1+1 + 5 + 8 );
/* sps id */
bs_read_ue( &s );
/* Skip i_log2_max_frame_num */
p_sys->i_log2_max_frame_num = bs_read_ue( &s );
/* Read poc_type */
i_tmp = bs_read_ue( &s );
if( i_tmp == 0 )
{
/* skip i_log2_max_poc_lsb */
bs_read_ue( &s );
}
else if( i_tmp == 1 )
{
int i_cycle;
/* skip b_delta_pic_order_always_zero */
bs_skip( &s, 1 );
/* skip i_offset_for_non_ref_pic */
bs_read_se( &s );
/* skip i_offset_for_top_to_bottom_field */
bs_read_se( &s );
/* read i_num_ref_frames_in_poc_cycle */
i_cycle = bs_read_ue( &s );
if( i_cycle > 256 ) i_cycle = 256;
while( i_cycle > 0 )
{
/* skip i_offset_for_ref_frame */
bs_read_se(&s );
}
}
/* i_num_ref_frames */
bs_read_ue( &s );
/* b_gaps_in_frame_num_value_allowed */
bs_skip( &s, 1 );
/* Read size */
p_dec->fmt_out.video.i_width = 16 * ( bs_read_ue( &s ) + 1 );
p_dec->fmt_out.video.i_height = 16 * ( bs_read_ue( &s ) + 1 );
/* b_frame_mbs_only */
p_sys->b_frame_mbs_only = bs_read( &s, 1 );
if( p_sys->b_frame_mbs_only == 0 )
{
bs_skip( &s, 1 );
}
/* b_direct8x8_inference */
bs_skip( &s, 1 );
/* crop */
i_tmp = bs_read( &s, 1 );
if( i_tmp )
{
/* left */
bs_read_ue( &s );
/* right */
bs_read_ue( &s );
/* top */
bs_read_ue( &s );
/* bottom */
bs_read_ue( &s );
}
/* vui */
i_tmp = bs_read( &s, 1 );
if( i_tmp )
{
/* read the aspect ratio part if any FIXME check it */
i_tmp = bs_read( &s, 1 );
if( i_tmp )
{
static const struct { int w, h; } sar[14] =
{
{ 0, 0 }, { 1, 1 }, { 12, 11 }, { 10, 11 },
{ 16, 11 }, { 40, 33 }, { 24, 11 }, { 20, 11 },
{ 32, 11 }, { 80, 33 }, { 18, 11 }, { 15, 11 },
{ 64, 33 }, { 160,99 },
};
int i_sar = bs_read( &s, 8 );
int w, h;
if( i_sar < 14 )
{
w = sar[i_sar].w;
h = sar[i_sar].h;
}
else
{
w = bs_read( &s, 16 );
h = bs_read( &s, 16 );
}
if( h != 0 )
p_dec->fmt_out.video.i_aspect =
VOUT_ASPECT_FACTOR * w / h * p_dec->fmt_out.video.i_width /
p_dec->fmt_out.video.i_height;
else
p_dec->fmt_out.video.i_aspect = VOUT_ASPECT_FACTOR;
}
}
free( dec );
if( p_sys->b_slice )
OUTPUT;
}
else if( i_nal_type == NAL_PPS )
{
bs_t s;
bs_init( &s, &p_frag->p_buffer[4], p_frag->i_buffer - 4 );
if( !p_sys->b_pps )
msg_Dbg( p_dec, "found NAL_PPS" );
p_sys->b_pps = VLC_TRUE;
/* TODO */
if( p_sys->b_slice )
OUTPUT;
}
else if( i_nal_type == NAL_AU_DELIMITER ||
i_nal_type == NAL_SEI ||
( i_nal_type >= 13 && i_nal_type <= 18 ) )
{
if( p_sys->b_slice )
OUTPUT;
}
#undef OUTPUT
/* Append the block */
block_ChainAppend( &p_sys->p_frame, p_frag );
return p_pic;
}
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