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/* GStreamer
* Copyright (C) <2007> Jan Schmidt <thaytan@mad.scientist.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __MPEGPACKETISER_H__
#define __MPEGPACKETISER_H__
#include <gst/gst.h>
#include <gst/base/gstadapter.h>
typedef struct MPEGPacketiser MPEGPacketiser;
typedef struct MPEGBlockInfo MPEGBlockInfo;
typedef struct MPEGSeqHdr MPEGSeqHdr;
typedef struct MPEGPictureHdr MPEGPictureHdr;
/* Packet ID codes for different packet types we
* care about */
#define MPEG_PACKET_PICTURE 0x00
#define MPEG_PACKET_SLICE_MIN 0x01
#define MPEG_PACKET_SLICE_MAX 0xaf
#define MPEG_PACKET_SEQUENCE 0xb3
#define MPEG_PACKET_EXTENSION 0xb5
#define MPEG_PACKET_SEQUENCE_END 0xb7
#define MPEG_PACKET_GOP 0xb8
#define MPEG_PACKET_NONE 0xff
/* Extension codes we care about */
#define MPEG_PACKET_EXT_SEQUENCE 0x01
#define MPEG_PACKET_EXT_SEQUENCE_DISPLAY 0x02
#define MPEG_PACKET_EXT_QUANT_MATRIX 0x03
/* Flags indicating what type of packets are in this block, some are mutually
* exclusive though - ie, sequence packs are accumulated separately. GOP &
* Picture may occur together or separately */
#define MPEG_BLOCK_FLAG_SEQUENCE 0x01
#define MPEG_BLOCK_FLAG_PICTURE 0x02
#define MPEG_BLOCK_FLAG_GOP 0x04
#define MPEG_PICTURE_TYPE_I 0x01
#define MPEG_PICTURE_TYPE_P 0x02
#define MPEG_PICTURE_TYPE_B 0x03
#define MPEG_PICTURE_TYPE_D 0x04
struct MPEGBlockInfo {
guint8 first_pack_type;
guint8 flags;
guint64 offset;
guint32 length;
GstClockTime ts;
};
struct MPEGSeqHdr
{
/* 0 for unknown, else 1 or 2 */
guint8 mpeg_version;
/* Pixel-Aspect Ratio from DAR code via set_par_from_dar */
gint par_w, par_h;
/* Width and Height of the video */
gint width, height;
/* Framerate */
gint fps_n, fps_d;
gboolean progressive;
};
struct MPEGPictureHdr
{
guint8 pic_type;
};
struct MPEGPacketiser {
GstAdapter *adapter;
/* position in the adapter */
guint64 adapter_offset;
/* Sync word accumulator */
guint32 sync_word;
/* Offset since the last flush (unrelated to incoming buffer offsets) */
guint64 tracked_offset;
/* Number of picture packets currently collected */
guint n_pictures;
/* 2 sets of timestamps + offsets used to mark picture blocks
* The first is used when a sync word overlaps packet boundaries
* and comes from some buffer in the past. The next one comes from current
* buffer. These are only ever valid when handling streams from a demuxer,
* of course. */
GstClockTime prev_buf_ts;
GstClockTime cur_buf_ts;
/* MPEG id of the previous SEQUENCE, PICTURE or GOP packet.
MPEG_PACKET_NONE after a flush */
guint8 prev_sync_packet;
/* Indices into the blocks array. cur_block_idx is where we're writing and
indicates the end of the populated block entries.
first_block_idx is the read ptr. It may be -1 to indicate there are no
complete blocks available */
gint cur_block_idx;
gint first_block_idx;
/* An array of MPEGBlockInfo entries, used as a growable circular buffer
* indexed by cur_block_idx and bounded by last_block_idx */
gint n_blocks;
MPEGBlockInfo *blocks;
};
void mpeg_packetiser_init (MPEGPacketiser *p);
void mpeg_packetiser_free (MPEGPacketiser *p);
void mpeg_packetiser_add_buf (MPEGPacketiser *p, GstBuffer *buf);
void mpeg_packetiser_handle_eos (MPEGPacketiser *p);
void mpeg_packetiser_flush (MPEGPacketiser *p);
/* Get the blockinfo and buffer for the block at the head of the queue */
MPEGBlockInfo *mpeg_packetiser_get_block (MPEGPacketiser *p, GstBuffer **buf);
/* Advance to the next data block */
void mpeg_packetiser_next_block (MPEGPacketiser *p);
/* Utility functions for parsing MPEG packets */
guint8 *mpeg_util_find_start_code (guint32 *sync_word,
guint8 *cur, guint8 *end);
gboolean mpeg_util_parse_sequence_hdr (MPEGSeqHdr *hdr,
guint8 *data, guint8 *end);
gboolean mpeg_util_parse_picture_hdr (MPEGPictureHdr *hdr,
guint8 *data, guint8 *end);
#endif
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