?? avformat.h
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//FIXME move stuff to a flags field?
/** quality, as it has been removed from AVCodecContext and put in AVVideoFrame
* MN:dunno if thats the right place, for it */
float quality;
/** decoding: position of the first frame of the component, in
AV_TIME_BASE fractional seconds. */
int64_t start_time;
/** decoding: duration of the stream, in AV_TIME_BASE fractional
seconds. */
int64_t duration;
char language[4]; /** ISO 639 3-letter language code (empty string if undefined) */
/* av_read_frame() support */
int need_parsing; ///< 1->full parsing needed, 2->only parse headers dont repack
struct AVCodecParserContext *parser;
int64_t cur_dts;
int last_IP_duration;
int64_t last_IP_pts;
/* av_seek_frame() support */
AVIndexEntry *index_entries; /**< only used if the format does not
support seeking natively */
int nb_index_entries;
unsigned int index_entries_allocated_size;
int64_t nb_frames; ///< number of frames in this stream if known or 0
#define MAX_REORDER_DELAY 4
int64_t pts_buffer[MAX_REORDER_DELAY+1];
} AVStream;
#define AVFMTCTX_NOHEADER 0x0001 /**< signal that no header is present
(streams are added dynamically) */
#define MAX_STREAMS 20
/* format I/O context */
typedef struct AVFormatContext {
const AVClass *av_class; /**< set by av_alloc_format_context */
/* can only be iformat or oformat, not both at the same time */
struct AVInputFormat *iformat;
struct AVOutputFormat *oformat;
void *priv_data;
ByteIOContext pb;
unsigned int nb_streams;
AVStream *streams[MAX_STREAMS];
char filename[1024]; /**< input or output filename */
/* stream info */
int64_t timestamp;
char title[512];
char author[512];
char copyright[512];
char comment[512];
char album[512];
int year; /**< ID3 year, 0 if none */
int track; /**< track number, 0 if none */
char genre[32]; /**< ID3 genre */
int ctx_flags; /**< format specific flags, see AVFMTCTX_xx */
/* private data for pts handling (do not modify directly) */
/** This buffer is only needed when packets were already buffered but
not decoded, for example to get the codec parameters in mpeg
streams */
struct AVPacketList *packet_buffer;
/** decoding: position of the first frame of the component, in
AV_TIME_BASE fractional seconds. NEVER set this value directly:
it is deduced from the AVStream values. */
int64_t start_time;
/** decoding: duration of the stream, in AV_TIME_BASE fractional
seconds. NEVER set this value directly: it is deduced from the
AVStream values. */
int64_t duration;
/** decoding: total file size. 0 if unknown */
int64_t file_size;
/** decoding: total stream bitrate in bit/s, 0 if not
available. Never set it directly if the file_size and the
duration are known as ffmpeg can compute it automatically. */
int bit_rate;
/* av_read_frame() support */
AVStream *cur_st;
const uint8_t *cur_ptr;
int cur_len;
AVPacket cur_pkt;
/* av_seek_frame() support */
int64_t data_offset; /** offset of the first packet */
int index_built;
int mux_rate;
int packet_size;
int preload;
int max_delay;
#define AVFMT_NOOUTPUTLOOP -1
#define AVFMT_INFINITEOUTPUTLOOP 0
/** number of times to loop output in formats that support it */
int loop_output;
int flags;
#define AVFMT_FLAG_GENPTS 0x0001 ///< generate pts if missing even if it requires parsing future frames
#define AVFMT_FLAG_IGNIDX 0x0002 ///< ignore index
int loop_input;
/** decoding: size of data to probe; encoding unused */
unsigned int probesize;
/**
* maximum duration in AV_TIME_BASE units over which the input should be analyzed in av_find_stream_info()
*/
int max_analyze_duration;
const uint8_t *key;
int keylen;
} AVFormatContext;
typedef struct AVPacketList {
AVPacket pkt;
struct AVPacketList *next;
} AVPacketList;
extern AVInputFormat *first_iformat;
extern AVOutputFormat *first_oformat;
enum CodecID av_guess_image2_codec(const char *filename);
/* XXX: use automatic init with either ELF sections or C file parser */
/* modules */
#include "rtp.h"
#include "rtsp.h"
/* utils.c */
void av_register_input_format(AVInputFormat *format);
void av_register_output_format(AVOutputFormat *format);
AVOutputFormat *guess_stream_format(const char *short_name,
const char *filename, const char *mime_type);
AVOutputFormat *guess_format(const char *short_name,
const char *filename, const char *mime_type);
/**
* Guesses the codec id based upon muxer and filename.
*/
enum CodecID av_guess_codec(AVOutputFormat *fmt, const char *short_name,
const char *filename, const char *mime_type, enum CodecType type);
/**
* Send a nice hexadecimal dump of a buffer to the specified file stream.
*
* @param f The file stream pointer where the dump should be sent to.
* @param buf buffer
* @param size buffer size
*
* @see av_hex_dump_log, av_pkt_dump, av_pkt_dump_log
*/
void av_hex_dump(FILE *f, uint8_t *buf, int size);
/**
* Send a nice hexadecimal dump of a buffer to the log.
*
* @param avcl A pointer to an arbitrary struct of which the first field is a
* pointer to an AVClass struct.
* @param level The importance level of the message, lower values signifying
* higher importance.
* @param buf buffer
* @param size buffer size
*
* @see av_hex_dump, av_pkt_dump, av_pkt_dump_log
*/
void av_hex_dump_log(void *avcl, int level, uint8_t *buf, int size);
/**
* Send a nice dump of a packet to the specified file stream.
*
* @param f The file stream pointer where the dump should be sent to.
* @param pkt packet to dump
* @param dump_payload true if the payload must be displayed too
*/
void av_pkt_dump(FILE *f, AVPacket *pkt, int dump_payload);
/**
* Send a nice dump of a packet to the log.
*
* @param avcl A pointer to an arbitrary struct of which the first field is a
* pointer to an AVClass struct.
* @param level The importance level of the message, lower values signifying
* higher importance.
* @param pkt packet to dump
* @param dump_payload true if the payload must be displayed too
*/
void av_pkt_dump_log(void *avcl, int level, AVPacket *pkt, int dump_payload);
void av_register_all(void);
/** codec tag <-> codec id */
enum CodecID av_codec_get_id(const struct AVCodecTag **tags, unsigned int tag);
unsigned int av_codec_get_tag(const struct AVCodecTag **tags, enum CodecID id);
/* media file input */
/**
* finds AVInputFormat based on input format's short name.
*/
AVInputFormat *av_find_input_format(const char *short_name);
/**
* Guess file format.
*
* @param is_opened whether the file is already opened, determines whether
* demuxers with or without AVFMT_NOFILE are probed
*/
AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened);
/**
* Allocates all the structures needed to read an input stream.
* This does not open the needed codecs for decoding the stream[s].
*/
int av_open_input_stream(AVFormatContext **ic_ptr,
ByteIOContext *pb, const char *filename,
AVInputFormat *fmt, AVFormatParameters *ap);
/**
* Open a media file as input. The codec are not opened. Only the file
* header (if present) is read.
*
* @param ic_ptr the opened media file handle is put here
* @param filename filename to open.
* @param fmt if non NULL, force the file format to use
* @param buf_size optional buffer size (zero if default is OK)
* @param ap additionnal parameters needed when opening the file (NULL if default)
* @return 0 if OK. AVERROR_xxx otherwise.
*/
int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
AVInputFormat *fmt,
int buf_size,
AVFormatParameters *ap);
/** no av_open for output, so applications will need this: */
AVFormatContext *av_alloc_format_context(void);
/**
* Read packets of a media file to get stream information. This
* is useful for file formats with no headers such as MPEG. This
* function also computes the real frame rate in case of mpeg2 repeat
* frame mode.
* The logical file position is not changed by this function;
* examined packets may be buffered for later processing.
*
* @param ic media file handle
* @return >=0 if OK. AVERROR_xxx if error.
* @todo let user decide somehow what information is needed so we dont waste time geting stuff the user doesnt need
*/
int av_find_stream_info(AVFormatContext *ic);
/**
* Read a transport packet from a media file.
*
* This function is absolete and should never be used.
* Use av_read_frame() instead.
*
* @param s media file handle
* @param pkt is filled
* @return 0 if OK. AVERROR_xxx if error.
*/
int av_read_packet(AVFormatContext *s, AVPacket *pkt);
/**
* Return the next frame of a stream.
*
* The returned packet is valid
* until the next av_read_frame() or until av_close_input_file() and
* must be freed with av_free_packet. For video, the packet contains
* exactly one frame. For audio, it contains an integer number of
* frames if each frame has a known fixed size (e.g. PCM or ADPCM
* data). If the audio frames have a variable size (e.g. MPEG audio),
* then it contains one frame.
*
* pkt->pts, pkt->dts and pkt->duration are always set to correct
* values in AVStream.timebase units (and guessed if the format cannot
* provided them). pkt->pts can be AV_NOPTS_VALUE if the video format
* has B frames, so it is better to rely on pkt->dts if you do not
* decompress the payload.
*
* @return 0 if OK, < 0 if error or end of file.
*/
int av_read_frame(AVFormatContext *s, AVPacket *pkt);
/**
* Seek to the key frame at timestamp.
* 'timestamp' in 'stream_index'.
* @param stream_index If stream_index is (-1), a default
* stream is selected, and timestamp is automatically converted
* from AV_TIME_BASE units to the stream specific time_base.
* @param timestamp timestamp in AVStream.time_base units
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