* mpegvideo.c
*****************************************************************************
* Copyright (C) 2001, 2002 VideoLAN
- * $Id: mpegvideo.c,v 1.12 2003/04/13 20:00:21 fenrir Exp $
+ * $Id: mpegvideo.c,v 1.19 2003/09/02 20:19:26 gbazin Exp $
*
* Authors: Laurent Aimar <fenrir@via.ecp.fr>
* Eric Petit <titer@videolan.org>
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
*****************************************************************************/
+/*****************************************************************************
+ * Problem with this implementation:
+ *
+ * Although we should time-stamp each picture with a PTS, this isn't possible
+ * with the current implementation.
+ * The problem comes from the fact that for non-low-delay streams we can't
+ * calculate the PTS of pictures used as backward reference. Even the temporal
+ * reference number doesn't help here because all the pictures don't
+ * necessarily have the same duration (eg. 3:2 pulldown).
+ *
+ * However this doesn't really matter as far as the MPEG muxers are concerned
+ * because they allow having empty PTS fields. --gibalou
+ *****************************************************************************/
+
/*****************************************************************************
* Preamble
*****************************************************************************/
sout_packetizer_input_t *p_sout_input;
sout_format_t output_format;
- mtime_t i_last_dts;
+ mtime_t i_interpolated_dts;
+ mtime_t i_old_duration;
mtime_t i_last_ref_pts;
double d_frame_rate;
int i_progressive_sequence;
+ int i_low_delay;
uint8_t p_sequence_header[150];
int i_sequence_header_length;
int i_last_sequence_header;
- int i_last_picture_structure;
} packetizer_t;
static int Open ( vlc_object_t * );
*****************************************************************************/
static int Open( vlc_object_t *p_this )
{
- decoder_fifo_t *p_fifo = (decoder_fifo_t*) p_this;
+ decoder_t *p_dec = (decoder_t*)p_this;
- if( p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', 'g', 'v') &&
- p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', 'g', '1') &&
- p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', 'g', '2') )
+ if( p_dec->p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', 'g', 'v') &&
+ p_dec->p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', 'g', '1') &&
+ p_dec->p_fifo->i_fourcc != VLC_FOURCC( 'm', 'p', 'g', '2') )
{
return VLC_EGENERIC;
}
- p_fifo->pf_run = Run;
+ p_dec->pf_run = Run;
return VLC_SUCCESS;
}
return -1;
}
- p_pack->i_last_picture_structure = 0x03; /* frame picture */
return( 0 );
}
/* converting frame_rate_code to frame_rate */
static const double pd_frame_rates[16] =
{
- 0, 24000/1001, 24, 25, 30000/1001, 30, 50, 60000/1001, 60,
+ 0, 24000.0/1001, 24, 25, 30000.0/1001, 30, 50, 60000.0/1001, 60,
0, 0, 0, 0, 0, 0, 0
};
static void PacketizeThread( packetizer_t *p_pack )
{
sout_buffer_t *p_sout_buffer = NULL;
+ vlc_bool_t b_seen_slice = VLC_FALSE;
int32_t i_pos;
int i_skipped;
mtime_t i_duration; /* of the parsed picture */
- mtime_t i_pts;
- mtime_t i_dts;
+ mtime_t i_pts = 0;
+ mtime_t i_dts = 0;
/* needed to calculate pts/dts */
int i_temporal_ref = 0;
+ int i_picture_coding_type = 0;
int i_picture_structure = 0x03; /* frame picture */
int i_top_field_first = 0;
int i_repeat_first_field = 0;
+ int i_progressive_frame = 0;
if( !p_pack->p_sout_input )
{
{
msg_Dbg( p_pack->p_fifo, "ARRGG no extension_start_code" );
p_pack->i_progressive_sequence = 1;
+ p_pack->i_low_delay = 1;
}
else
{
GetChunk( &p_pack->bit_stream, p_temp + i_pos, 10 );
p_pack->i_progressive_sequence = ( p_temp[i_pos+5]&0x08 ) ? 1 : 0;
-
+ p_pack->i_low_delay = ( p_temp[i_pos+9]&0x80 ) ? 1 : 0;
i_pos += 10;
}
else
{
p_sout_buffer =
- sout_BufferNew( p_pack->p_sout_input->p_sout, 100 * 1024 );
+ sout_BufferNew( p_pack->p_sout_input->p_sout, 100 * 1024 );
i_pos = 0;
}
for( ;; )
{
- uint32_t i_code;
+ uint32_t i_code;
if( p_pack->p_fifo->b_die || p_pack->p_fifo->b_error )
{
break;
i_code = ShowBits( &p_pack->bit_stream, 32 );
+ if( b_seen_slice && ( i_code < 0x101 || i_code > 0x1af ) )
+ {
+ break;
+ }
+
if( i_code == 0x1B8 ) /* GOP */
{
/* usefull for bad MPEG-1 : repeat the sequence_header
i_pos += p_pack->i_sequence_header_length;
p_pack->i_last_sequence_header = 0;
}
-
- p_pack->i_last_ref_pts =
- p_pack->i_last_dts +
- (mtime_t)( 1000000 / p_pack->d_frame_rate); /* FIXME */
CopyUntilNextStartCode( p_pack, p_sout_buffer, &i_pos );
}
else if( i_code == 0x100 ) /* Picture */
NextPTS( &p_pack->bit_stream, &i_pts, &i_dts );
i_temporal_ref = ShowBits( &p_pack->bit_stream, 10 );
+ i_picture_coding_type = ShowBits( &p_pack->bit_stream, 13 ) & 0x3;
CopyUntilNextStartCode( p_pack, p_sout_buffer, &i_pos );
- break;
}
else if( i_code == 0x1b5 )
{
ShowBits( &p_pack->bit_stream, 25 ) & 0x01;
i_repeat_first_field =
ShowBits( &p_pack->bit_stream, 31 ) & 0x01;
+
+ GetChunk( &p_pack->bit_stream,
+ p_sout_buffer->p_buffer + i_pos, 4 ); i_pos += 4;
+
+ i_progressive_frame =
+ ShowBits( &p_pack->bit_stream, 1 ) & 0x01;
}
CopyUntilNextStartCode( p_pack, p_sout_buffer, &i_pos );
}
else
{
+ if( i_code >= 0x101 && i_code <= 0x1af )
+ {
+ b_seen_slice = VLC_TRUE;
+ }
+
if( i_code == 0x1B3 )
{
p_pack->i_last_sequence_header = 0;
}
}
+ if( i_pts <= 0 && i_dts <= 0 && p_pack->i_interpolated_dts <= 0 )
+ {
+ msg_Dbg( p_pack->p_fifo, "need a starting pts/dts" );
+ sout_BufferDelete( p_pack->p_sout_input->p_sout, p_sout_buffer );
+ return;
+ }
+
sout_BufferRealloc( p_pack->p_sout_input->p_sout,
p_sout_buffer, i_pos );
p_sout_buffer->i_size = i_pos;
- /* calculate dts/pts */
+ /* calculate frame duration */
if( p_pack->i_progressive_sequence || i_picture_structure == 0x03)
{
i_duration = (mtime_t)( 1000000 / p_pack->d_frame_rate );
i_duration = (mtime_t)( 1000000 / p_pack->d_frame_rate / 2);
}
- /* fix i_last_dts and i_last_ref_pts with i_dts and i_pts from stream */
- if( i_dts <= 0 && p_pack->i_last_dts <= 0 )
+ if( p_pack->i_progressive_sequence )
{
- msg_Dbg( p_pack->p_fifo, "need a starting pts" );
- sout_BufferDelete( p_pack->p_sout_input->p_sout,
- p_sout_buffer );
- return;
+ if( i_top_field_first == 0 && i_repeat_first_field == 1 )
+ {
+ i_duration = 2 * i_duration;
+ }
+ else if( i_top_field_first == 1 && i_repeat_first_field == 1 )
+ {
+ i_duration = 3 * i_duration;
+ }
}
-
-#if 1
- if( i_dts > 0 )
+ else
{
- //if( i_dts - p_pack->i_last_dts > 200000 ||
- // i_dts - p_pack->i_last_dts < 200000 )
+ if( i_picture_structure == 0x03 )
{
- p_pack->i_last_dts = i_dts;
- if( i_pts > 0 )
+ if( i_progressive_frame && i_repeat_first_field )
{
- p_pack->i_last_ref_pts = i_pts -
- i_temporal_ref * (mtime_t)( 1000000 / p_pack->d_frame_rate );
+ i_duration += i_duration / 2;
}
}
}
-#endif
- p_sout_buffer->i_dts = p_pack->i_last_dts;
- p_sout_buffer->i_pts = p_pack->i_last_ref_pts +
- i_temporal_ref * (mtime_t)( 1000000 / p_pack->d_frame_rate );
- p_sout_buffer->i_length = i_duration;
- p_sout_buffer->i_bitrate = (int)( 8 * i_pos * p_pack->d_frame_rate );
- sout_InputSendBuffer( p_pack->p_sout_input, p_sout_buffer );
+ if( p_pack->i_low_delay || i_picture_coding_type == 0x03 )
+ {
+ /* Trivial case (DTS == PTS) */
+ /* Correct interpolated dts when we receive a new pts/dts */
+ if( i_pts > 0 ) p_pack->i_interpolated_dts = i_pts;
+ if( i_dts > 0 ) p_pack->i_interpolated_dts = i_dts;
+ }
+ else
+ {
+ /* Correct interpolated dts when we receive a new pts/dts */
+ if( p_pack->i_last_ref_pts )
+ p_pack->i_interpolated_dts = p_pack->i_last_ref_pts;
+ if( i_dts > 0 ) p_pack->i_interpolated_dts = i_dts;
- if( p_pack->i_progressive_sequence )
+ p_pack->i_last_ref_pts = i_pts;
+ }
+
+ /* Don't even try to calculate the PTS unless it is given in the
+ * original stream */
+ p_sout_buffer->i_pts = i_pts ? i_pts : -1;
+
+ p_sout_buffer->i_dts = p_pack->i_interpolated_dts;
+
+ if( p_pack->i_low_delay || i_picture_coding_type == 0x03 )
{
- if( i_top_field_first == 0 && i_repeat_first_field == 0 )
- {
- p_pack->i_last_dts += i_duration;
- }
- else if( i_top_field_first == 0 && i_repeat_first_field == 1 )
- {
- p_pack->i_last_dts += 2 * i_duration;
- }
- else if( i_top_field_first == 1 && i_repeat_first_field == 1 )
- {
- p_pack->i_last_dts += 3 * i_duration;
- }
+ /* Trivial case (DTS == PTS) */
+ p_pack->i_interpolated_dts += i_duration;
}
else
{
- if( i_picture_structure == 0x03 )
- {
- p_pack->i_last_dts += i_duration;
- }
- else if( i_picture_structure == p_pack->i_last_picture_structure )
- {
- p_pack->i_last_dts += 2 * i_duration;
- }
- else if( ( !i_top_field_first && i_picture_structure == 0x01 ) ||
- ( i_top_field_first && i_picture_structure == 0x02 ) )
- {
- p_pack->i_last_dts += 2 * i_duration;
- }
+ p_pack->i_interpolated_dts += p_pack->i_old_duration;
+ p_pack->i_old_duration = i_duration;
}
- p_pack->i_last_picture_structure = i_picture_structure;
+
+ p_sout_buffer->i_length = p_pack->i_interpolated_dts -
+ p_sout_buffer->i_dts;
+
+ p_sout_buffer->i_bitrate = (int)( 8 * i_pos * p_pack->d_frame_rate );
+
+#if 0
+ msg_Dbg( p_pack->p_fifo, "------------> dts=%lld pts=%lld duration=%lld",
+ p_sout_buffer->i_dts, p_sout_buffer->i_pts,
+ p_sout_buffer->i_length );
+#endif
+
+ sout_InputSendBuffer( p_pack->p_sout_input, p_sout_buffer );
}
projects / vlc / blobdiff