FFmpeg/libavformat/rm.h

/*
 * "Real" compatible muxer and demuxer.
 * Copyright (c) 2000, 2001 Fabrice Bellard
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef AVFORMAT_RM_H
#define AVFORMAT_RM_H

#include "avformat.h"
#include "internal.h"

extern const char * const ff_rm_metadata[4];
extern const unsigned char ff_sipr_subpk_size[4];
extern const AVCodecTag ff_rm_codec_tags[];

typedef struct RMStream RMStream;

RMStream *ff_rm_alloc_rmstream (void);
void      ff_rm_free_rmstream  (RMStream *rms);

/*< input format for Realmedia-style RTSP streams */
extern AVInputFormat rdt_demuxer;

/**
 * Read the MDPR chunk, which contains stream-specific codec initialization
 * parameters.
 *
 * @param s context containing RMContext and ByteIOContext for stream reading
 * @param pb context to read the data from
 * @param st the stream that the MDPR chunk belongs to and where to store the
 *           parameters read from the chunk into
 * @param rst real-specific stream information
 * @param codec_data_size size of the MDPR chunk
 * @return 0 on success, errno codes on error
 */
int ff_rm_read_mdpr_codecdata (AVFormatContext *s, ByteIOContext *pb,
                               AVStream *st, RMStream *rst,
                               int codec_data_size);

/**
 * Parse one rm-stream packet from the input bytestream.
 *
 * @param s context containing RMContext and ByteIOContext for stream reading
 * @param pb context to read the data from
 * @param st stream to which the packet to be read belongs
 * @param rst Real-specific stream information
 * @param len packet length to read from the input
 * @param pkt packet location to store the parsed packet data
 * @param seq pointer to an integer containing the sequence number, may be
 *            updated
 * @param flags the packet flags
 * @param ts timestamp of the current packet
 * @return <0 on error, 0 if a packet was placed in the pkt pointer. A
 *         value >0 means that no data was placed in pkt, but that cached
 *         data is available by calling ff_rm_retrieve_cache().
 */
int ff_rm_parse_packet (AVFormatContext *s, ByteIOContext *pb,
                        AVStream *st, RMStream *rst, int len,
                        AVPacket *pkt, int *seq, int flags, int64_t ts);

/**
 * Retrieve one cached packet from the rm-context. The real container can
 * store several packets (as interpreted by the codec) in a single container
 * packet, which means the demuxer holds some back when the first container
 * packet is parsed and returned. The result is that rm->audio_pkt_cnt is
 * a positive number, the amount of cached packets. Using this function, each
 * of those packets can be retrieved sequentially.
 *
 * @param s context containing RMContext and ByteIOContext for stream reading
 * @param pb context to read the data from
 * @param st stream that this packet belongs to
 * @param rst Real-specific stream information
 * @param pkt location to store the packet data
 * @return the number of samples left for subsequent calls to this same
 *          function, or 0 if all samples have been retrieved.
 */
int ff_rm_retrieve_cache (AVFormatContext *s, ByteIOContext *pb,
                          AVStream *st, RMStream *rst, AVPacket *pkt);

/**
 * Perform 4-bit block reordering for SIPR data.
 *
 * @param buf SIPR data
 */
void ff_rm_reorder_sipr_data(uint8_t *buf, int sub_packet_h, int framesize);

#endif /* AVFORMAT_RM_H */