[vlc-devel] [PATCH 3/5] mux/mpeg/pes: Add support for stream_id_extension
davidf+nntp at woaf.net
davidf+nntp at woaf.net
Fri Nov 14 22:46:38 CET 2008
From: David Flynn <davidf at rd.bbc.co.uk>
ISO/IEC 13818-1:2000/Amd.2:2003 Adds support for signalling
a stream_id_extension. This is used in mapping standards
for Dirac/VC-2 and VC-1.
Signed-off-by: David Flynn <davidf at rd.bbc.co.uk>
---
modules/mux/mpeg/pes.c | 60 ++++++++++++++++++++++++++++++++++++++++++++++-
modules/mux/mpeg/pes.h | 1 +
2 files changed, 59 insertions(+), 2 deletions(-)
diff --git a/modules/mux/mpeg/pes.c b/modules/mux/mpeg/pes.c
index 7198a4d..f3742b0 100644
--- a/modules/mux/mpeg/pes.c
+++ b/modules/mux/mpeg/pes.c
@@ -50,6 +50,10 @@
/** PESHeader, write a pes header
* \param i_es_size length of payload data. (Must be < PES_PAYLOAD_SIZE_MAX
* unless the conditions for unbounded PES packets are met)
+ * \param i_stream_id stream id as follows:
+ * - 0x00 - 0xff : normal stream_id as per Table 2-18
+ * - 0xfd00 - 0xfd7f : stream_id_extension = low 7 bits
+ * (stream_id = PES_EXTENDED_STREAM_ID)
* \param i_header_size length of padding data to insert into PES packet
* header in bytes.
*/
@@ -61,6 +65,7 @@ static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
{
bits_buffer_t bits;
int i_extra = 0;
+ int i_stream_id_extension = 0;
/* For PES_PRIVATE_STREAM_1 there is an extra header after the
pes header */
@@ -74,6 +79,15 @@ static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
}
}
+ if( ( i_stream_id >> 8 ) == PES_EXTENDED_STREAM_ID )
+ {
+ /* Enable support for extended_stream_id as defined in
+ * ISO/IEC 13818-1:2000/Amd.2:2003 */
+ /* NB, i_extended_stream_id is limited to 7 bits */
+ i_stream_id_extension = i_stream_id & 0x7f;
+ i_stream_id = PES_EXTENDED_STREAM_ID;
+ }
+
bits_initwrite( &bits, 50, p_hdr );
/* add start code */
@@ -99,6 +113,7 @@ static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
if( b_mpeg2 )
{
int i_pts_dts;
+ bool b_pes_extension_flag = false;
if( i_pts > 0 && i_dts > 0 &&
( i_pts != i_dts || ( p_fmt->i_cat == VIDEO_ES &&
@@ -118,6 +133,17 @@ static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
if ( !i_header_size ) i_header_size = 0x0;
}
+ if( i_stream_id == 0xfd )
+ {
+ b_pes_extension_flag = true;
+ i_header_size += 1 + 1;
+ }
+
+ if( b_pes_extension_flag )
+ {
+ i_header_size += 1;
+ }
+
/* Unbounded streams are only allowed in TS (not PS) and only
* for some ES, eg. MPEG* Video ES or Dirac ES. */
if( i_es_size > PES_PAYLOAD_SIZE_MAX )
@@ -138,8 +164,8 @@ static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
bits_write( &bits, 1, 0x00 ); // dsm trick mode flag
bits_write( &bits, 1, 0x00 ); // additional copy info flag
bits_write( &bits, 1, 0x00 ); // pes crc flag
- bits_write( &bits, 1, 0x00 ); // pes extension flags
- bits_write( &bits, 8, i_header_size ); // header size -> pts and dts
+ bits_write( &bits, 1, b_pes_extension_flag );
+ bits_write( &bits, 8, i_header_size );
/* write pts */
if( i_pts_dts & 0x02 )
@@ -165,6 +191,30 @@ static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
bits_write( &bits, 1, 0x01 ); // marker
i_header_size -= 0x5;
}
+ if( b_pes_extension_flag )
+ {
+ bits_write( &bits, 1, 0x00 ); // PES_private_data_flag
+ bits_write( &bits, 1, 0x00 ); // pack_header_field_flag
+ bits_write( &bits, 1, 0x00 ); // program_packet_sequence_counter_flag
+ bits_write( &bits, 1, 0x00 ); // P-STD_buffer_flag
+ bits_write( &bits, 3, 0x07 ); // reserved
+ bits_write( &bits, 1, 0x01 ); // PES_extension_flag_2
+ /* skipping unsupported parts: */
+ /* PES_private_data */
+ /* pack_header */
+ /* program_packet_sequence_counter */
+ /* P-STD_buffer_flag */
+ if( i_stream_id == 0xfd )
+ {
+ /* PES_extension_2 */
+ bits_write( &bits, 1, 0x01 ); // marker
+ bits_write( &bits, 7, 0x01 ); // PES_extension_field_length
+ bits_write( &bits, 1, 0x01 ); // stream_id_extension_flag
+ bits_write( &bits, 7, i_stream_id_extension );
+ i_header_size -= 0x2;
+ }
+ i_header_size -= 0x1;
+ }
while ( i_header_size )
{
bits_write( &bits, 8, 0xff );
@@ -257,6 +307,12 @@ static inline int PESHeader( uint8_t *p_hdr, mtime_t i_pts, mtime_t i_dts,
* If the last condition is not met, a single PES packet is produced
* which is not unbounded in length.
*
+ * \param i_stream_id stream id as follows:
+ * - 0x00 - 0xff : normal stream_id as per Table 2-18
+ * - 0xfd00 - 0xfd7f : stream_id_extension = low 7 bits
+ * (stream_id = PES_EXTENDED_STREAM_ID)
+ * - 0xbd00 - 0xbdff : private_id = low 8 bits
+ * (stream_id = PES_PRIVATE_STREAM)
* \param i_header_size length of padding data to insert into PES packet
* header in bytes.
* \param i_max_pes_size maximum length of each pes packet payload.
diff --git a/modules/mux/mpeg/pes.h b/modules/mux/mpeg/pes.h
index 5b7aab4..818c82d 100644
--- a/modules/mux/mpeg/pes.h
+++ b/modules/mux/mpeg/pes.h
@@ -31,6 +31,7 @@
#define PES_PROGRAM_STREAM_DIRECTORY 0xff
#define PES_DSMCC_STREAM 0xf2
#define PES_ITU_T_H222_1_TYPE_E_STREAM 0xf8
+#define PES_EXTENDED_STREAM_ID 0xfd
#define PES_PAYLOAD_SIZE_MAX 65500
--
1.5.6.5
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