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ffmpeg/libavformat/internal.h

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/*
* copyright (c) 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_INTERNAL_H
#define AVFORMAT_INTERNAL_H
#include <stdint.h>
#include "libavcodec/packet_internal.h"
#include "avformat.h"
#define MAX_URL_SIZE 4096
/** size of probe buffer, for guessing file type from file contents */
#define PROBE_BUF_MIN 2048
#define PROBE_BUF_MAX (1 << 20)
#ifdef DEBUG
# define hex_dump_debug(class, buf, size) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size)
#else
# define hex_dump_debug(class, buf, size) do { if (0) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size); } while(0)
#endif
typedef struct AVCodecTag {
enum AVCodecID id;
unsigned int tag;
} AVCodecTag;
typedef struct CodecMime{
char str[32];
enum AVCodecID id;
} CodecMime;
/*************************************************/
/* fractional numbers for exact pts handling */
/**
* The exact value of the fractional number is: 'val + num / den'.
* num is assumed to be 0 <= num < den.
*/
typedef struct FFFrac {
int64_t val, num, den;
} FFFrac;
typedef struct FFFormatContext {
/**
* The public context.
*/
AVFormatContext pub;
/**
* Number of streams relevant for interleaving.
* Muxing only.
*/
int nb_interleaved_streams;
/**
* Whether the timestamp shift offset has already been determined.
* -1: disabled, 0: not yet determined, 1: determined.
*/
enum {
AVOID_NEGATIVE_TS_DISABLED = -1,
AVOID_NEGATIVE_TS_UNKNOWN = 0,
AVOID_NEGATIVE_TS_KNOWN = 1,
} avoid_negative_ts_status;
#define AVOID_NEGATIVE_TS_ENABLED(status) ((status) >= 0)
/**
* The interleavement function in use. Always set for muxers.
*/
int (*interleave_packet)(struct AVFormatContext *s, AVPacket *pkt,
int flush, int has_packet);
/**
* This buffer is only needed when packets were already buffered but
* not decoded, for example to get the codec parameters in MPEG
* streams.
*/
PacketList packet_buffer;
/* av_seek_frame() support */
int64_t data_offset; /**< offset of the first packet */
/**
* Raw packets from the demuxer, prior to parsing and decoding.
* This buffer is used for buffering packets until the codec can
* be identified, as parsing cannot be done without knowing the
* codec.
*/
PacketList raw_packet_buffer;
/**
* Packets split by the parser get queued here.
*/
PacketList parse_queue;
/**
* The generic code uses this as a temporary packet
* to parse packets or for muxing, especially flushing.
* For demuxers, it may also be used for other means
* for short periods that are guaranteed not to overlap
* with calls to av_read_frame() (or ff_read_packet())
* or with each other.
* It may be used by demuxers as a replacement for
* stack packets (unless they call one of the aforementioned
* functions with their own AVFormatContext).
* Every user has to ensure that this packet is blank
* after using it.
*/
AVPacket *parse_pkt;
/**
* Used to hold temporary packets for the generic demuxing code.
* When muxing, it may be used by muxers to hold packets (even
* permanent ones).
*/
AVPacket *pkt;
/**
* Sum of the size of packets in raw_packet_buffer, in bytes.
*/
int raw_packet_buffer_size;
#if FF_API_COMPUTE_PKT_FIELDS2
int missing_ts_warning;
#endif
#if FF_API_AVSTREAM_SIDE_DATA
int inject_global_side_data;
#endif
int avoid_negative_ts_use_pts;
#if FF_API_LAVF_SHORTEST
/**
* Timestamp of the end of the shortest stream.
*/
int64_t shortest_end;
#endif
/**
* Whether or not avformat_init_output has already been called
*/
int initialized;
/**
* Whether or not avformat_init_output fully initialized streams
*/
int streams_initialized;
/**
* ID3v2 tag useful for MP3 demuxing
*/
AVDictionary *id3v2_meta;
/*
* Prefer the codec framerate for avg_frame_rate computation.
*/
int prefer_codec_framerate;
/**
* Set if chapter ids are strictly monotonic.
*/
int chapter_ids_monotonic;
/**
* Contexts and child contexts do not contain a metadata option
*/
int metafree;
} FFFormatContext;
static av_always_inline FFFormatContext *ffformatcontext(AVFormatContext *s)
{
return (FFFormatContext*)s;
}
typedef struct FFStream {
/**
* The public context.
*/
AVStream pub;
AVFormatContext *fmtctx;
/**
* Set to 1 if the codec allows reordering, so pts can be different
* from dts.
*/
int reorder;
/**
* bitstream filter to run on stream
* - encoding: Set by muxer using ff_stream_add_bitstream_filter
* - decoding: unused
*/
struct AVBSFContext *bsfc;
/**
* Whether or not check_bitstream should still be run on each packet
*/
int bitstream_checked;
/**
* The codec context used by avformat_find_stream_info, the parser, etc.
*/
struct AVCodecContext *avctx;
/**
* 1 if avctx has been initialized with the values from the codec parameters
*/
int avctx_inited;
/* the context for extracting extradata in find_stream_info()
* inited=1/bsf=NULL signals that extracting is not possible (codec not
* supported) */
struct {
struct AVBSFContext *bsf;
int inited;
} extract_extradata;
/**
* Whether the internal avctx needs to be updated from codecpar (after a late change to codecpar)
*/
int need_context_update;
int is_intra_only;
FFFrac priv_pts;
/**
* Stream information used internally by avformat_find_stream_info()
*/
struct FFStreamInfo *info;
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 interleaver_chunk_size;
int64_t interleaver_chunk_duration;
/**
* stream probing state
* -1 -> probing finished
* 0 -> no probing requested
* rest -> perform probing with request_probe being the minimum score to accept.
*/
int request_probe;
/**
* Indicates that everything up to the next keyframe
* should be discarded.
*/
int skip_to_keyframe;
/**
* Number of samples to skip at the start of the frame decoded from the next packet.
*/
int skip_samples;
/**
* If not 0, the number of samples that should be skipped from the start of
* the stream (the samples are removed from packets with pts==0, which also
* assumes negative timestamps do not happen).
* Intended for use with formats such as mp3 with ad-hoc gapless audio
* support.
*/
int64_t start_skip_samples;
/**
* If not 0, the first audio sample that should be discarded from the stream.
* This is broken by design (needs global sample count), but can't be
* avoided for broken by design formats such as mp3 with ad-hoc gapless
* audio support.
*/
int64_t first_discard_sample;
/**
* The sample after last sample that is intended to be discarded after
* first_discard_sample. Works on frame boundaries only. Used to prevent
* early EOF if the gapless info is broken (considered concatenated mp3s).
*/
int64_t last_discard_sample;
/**
* Number of internally decoded frames, used internally in libavformat, do not access
* its lifetime differs from info which is why it is not in that structure.
*/
int nb_decoded_frames;
/**
* Timestamp offset added to timestamps before muxing
*/
int64_t mux_ts_offset;
/**
* This is the lowest ts allowed in this track; it may be set by the muxer
* during init or write_header and influences the automatic timestamp
* shifting code.
*/
int64_t lowest_ts_allowed;
/**
* Internal data to check for wrapping of the time stamp
*/
int64_t pts_wrap_reference;
/**
* Options for behavior, when a wrap is detected.
*
* Defined by AV_PTS_WRAP_ values.
*
* If correction is enabled, there are two possibilities:
* If the first time stamp is near the wrap point, the wrap offset
* will be subtracted, which will create negative time stamps.
* Otherwise the offset will be added.
*/
int pts_wrap_behavior;
/**
* Internal data to prevent doing update_initial_durations() twice
*/
int update_initial_durations_done;
#define MAX_REORDER_DELAY 16
/**
* Internal data to generate dts from pts
*/
int64_t pts_reorder_error[MAX_REORDER_DELAY+1];
uint8_t pts_reorder_error_count[MAX_REORDER_DELAY+1];
int64_t pts_buffer[MAX_REORDER_DELAY+1];
/**
* Internal data to analyze DTS and detect faulty mpeg streams
*/
int64_t last_dts_for_order_check;
uint8_t dts_ordered;
uint8_t dts_misordered;
#if FF_API_AVSTREAM_SIDE_DATA
/**
* Internal data to inject global side data
*/
int inject_global_side_data;
#endif
/**
* display aspect ratio (0 if unknown)
* - encoding: unused
* - decoding: Set by libavformat to calculate sample_aspect_ratio internally
*/
AVRational display_aspect_ratio;
AVProbeData probe_data;
/**
* last packet in packet_buffer for this stream when muxing.
*/
PacketListEntry *last_in_packet_buffer;
int64_t last_IP_pts;
int last_IP_duration;
/**
* Number of packets to buffer for codec probing
*/
int probe_packets;
/* av_read_frame() support */
enum AVStreamParseType need_parsing;
struct AVCodecParserContext *parser;
/**
* Number of frames that have been demuxed during avformat_find_stream_info()
*/
int codec_info_nb_frames;
/**
* Stream Identifier
* This is the MPEG-TS stream identifier +1
* 0 means unknown
*/
int stream_identifier;
// Timestamp generation support:
/**
* Timestamp corresponding to the last dts sync point.
*
* Initialized when AVCodecParserContext.dts_sync_point >= 0 and
* a DTS is received from the underlying container. Otherwise set to
* AV_NOPTS_VALUE by default.
*/
int64_t first_dts;
int64_t cur_dts;
const struct AVCodecDescriptor *codec_desc;
AVRational transferred_mux_tb;
} FFStream;
static av_always_inline FFStream *ffstream(AVStream *st)
{
return (FFStream*)st;
}
static av_always_inline const FFStream *cffstream(const AVStream *st)
{
return (const FFStream*)st;
}
typedef struct FFStreamGroup {
/**
* The public context.
*/
AVStreamGroup pub;
AVFormatContext *fmtctx;
} FFStreamGroup;
static av_always_inline FFStreamGroup *ffstreamgroup(AVStreamGroup *stg)
{
return (FFStreamGroup*)stg;
}
static av_always_inline const FFStreamGroup *cffstreamgroup(const AVStreamGroup *stg)
{
return (const FFStreamGroup*)stg;
}
#ifdef __GNUC__
#define dynarray_add(tab, nb_ptr, elem)\
do {\
__typeof__(tab) _tab = (tab);\
__typeof__(elem) _elem = (elem);\
(void)sizeof(**_tab == _elem); /* check that types are compatible */\
av_dynarray_add(_tab, nb_ptr, _elem);\
} while(0)
#else
#define dynarray_add(tab, nb_ptr, elem)\
do {\
av_dynarray_add((tab), nb_ptr, (elem));\
} while(0)
#endif
void ff_flush_packet_queue(AVFormatContext *s);
/**
* Automatically create sub-directories
*
* @param path will create sub-directories by path
* @return 0, or < 0 on error
*/
int ff_mkdir_p(const char *path);
/**
* Write hexadecimal string corresponding to given binary data. The string
* is zero-terminated.
*
* @param buf the output string is written here;
* needs to be at least 2 * size + 1 bytes long.
* @param src the input data to be transformed.
* @param size the size (in byte) of src.
* @param lowercase determines whether to use the range [0-9a-f] or [0-9A-F].
* @return buf.
*/
char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
/**
* Parse a string of hexadecimal strings. Any space between the hexadecimal
* digits is ignored.
*
* @param data if non-null, the parsed data is written to this pointer
* @param p the string to parse
* @return the number of bytes written (or to be written, if data is null)
*/
int ff_hex_to_data(uint8_t *data, const char *p);
#define NTP_OFFSET 2208988800ULL
#define NTP_OFFSET_US (NTP_OFFSET * 1000000ULL)
/** Get the current time since NTP epoch in microseconds. */
uint64_t ff_ntp_time(void);
/**
* Get the NTP time stamp formatted as per the RFC-5905.
*
* @param ntp_time NTP time in micro seconds (since NTP epoch)
* @return the formatted NTP time stamp
*/
uint64_t ff_get_formatted_ntp_time(uint64_t ntp_time_us);
/**
* Parse the NTP time in micro seconds (since NTP epoch).
*
* @param ntp_ts NTP time stamp formatted as per the RFC-5905.
* @return the time in micro seconds (since NTP epoch)
*/
uint64_t ff_parse_ntp_time(uint64_t ntp_ts);
/**
* Append the media-specific SDP fragment for the media stream c
* to the buffer buff.
*
* Note, the buffer needs to be initialized, since it is appended to
* existing content.
*
* @param buff the buffer to append the SDP fragment to
* @param size the size of the buff buffer
* @param st the AVStream of the media to describe
* @param idx the global stream index
* @param dest_addr the destination address of the media stream, may be NULL
* @param dest_type the destination address type, may be NULL
* @param port the destination port of the media stream, 0 if unknown
* @param ttl the time to live of the stream, 0 if not multicast
* @param fmt the AVFormatContext, which might contain options modifying
* the generated SDP
* @return 0 on success, a negative error code on failure
*/
int ff_sdp_write_media(char *buff, int size, const AVStream *st, int idx,
const char *dest_addr, const char *dest_type,
int port, int ttl, AVFormatContext *fmt);
/**
* Read a whole line of text from AVIOContext. Stop reading after reaching
* either a \\n, a \\0 or EOF. The returned string is always \\0-terminated,
* and may be truncated if the buffer is too small.
*
* @param s the read-only AVIOContext
* @param buf buffer to store the read line
* @param maxlen size of the buffer
* @return the length of the string written in the buffer, not including the
* final \\0
*/
int ff_get_line(AVIOContext *s, char *buf, int maxlen);
/**
* Same as ff_get_line but strip the white-space characters in the text tail
*
* @param s the read-only AVIOContext
* @param buf buffer to store the read line
* @param maxlen size of the buffer
* @return the length of the string written in the buffer
*/
int ff_get_chomp_line(AVIOContext *s, char *buf, int maxlen);
#define SPACE_CHARS " \t\r\n"
/**
* Callback function type for ff_parse_key_value.
*
* @param key a pointer to the key
* @param key_len the number of bytes that belong to the key, including the '='
* char
* @param dest return the destination pointer for the value in *dest, may
* be null to ignore the value
* @param dest_len the length of the *dest buffer
*/
typedef void (*ff_parse_key_val_cb)(void *context, const char *key,
int key_len, char **dest, int *dest_len);
/**
* Parse a string with comma-separated key=value pairs. The value strings
* may be quoted and may contain escaped characters within quoted strings.
*
* @param str the string to parse
* @param callback_get_buf function that returns where to store the
* unescaped value string.
* @param context the opaque context pointer to pass to callback_get_buf
*/
void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
void *context);
enum AVCodecID ff_guess_image2_codec(const char *filename);
const struct AVCodec *ff_find_decoder(AVFormatContext *s, const AVStream *st,
enum AVCodecID codec_id);
/**
* Set the time base and wrapping info for a given stream. This will be used
* to interpret the stream's timestamps. If the new time base is invalid
* (numerator or denominator are non-positive), it leaves the stream
* unchanged.
*
* @param st stream
* @param pts_wrap_bits number of bits effectively used by the pts
* (used for wrap control)
* @param pts_num time base numerator
* @param pts_den time base denominator
*/
void avpriv_set_pts_info(AVStream *st, int pts_wrap_bits,
unsigned int pts_num, unsigned int pts_den);
/**
* Set the timebase for each stream from the corresponding codec timebase and
* print it.
*/
int ff_framehash_write_header(AVFormatContext *s);
/**
* Frees a stream without modifying the corresponding AVFormatContext.
* Must only be called if the latter doesn't matter or if the stream
* is not yet attached to an AVFormatContext.
*/
void ff_free_stream(AVStream **st);
/**
* Remove a stream from its AVFormatContext and free it.
* The stream must be the last stream of the AVFormatContext.
*/
void ff_remove_stream(AVFormatContext *s, AVStream *st);
/**
* Frees a stream group without modifying the corresponding AVFormatContext.
* Must only be called if the latter doesn't matter or if the stream
* is not yet attached to an AVFormatContext.
*/
void ff_free_stream_group(AVStreamGroup **pstg);
/**
* Remove a stream group from its AVFormatContext and free it.
* The stream group must be the last stream group of the AVFormatContext.
*/
void ff_remove_stream_group(AVFormatContext *s, AVStreamGroup *stg);
unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id);
enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag);
int ff_is_intra_only(enum AVCodecID id);
/**
* Select a PCM codec based on the given parameters.
*
* @param bps bits-per-sample
* @param flt floating-point
* @param be big-endian
* @param sflags signed flags. each bit corresponds to one byte of bit depth.
* e.g. the 1st bit indicates if 8-bit should be signed or
* unsigned, the 2nd bit indicates if 16-bit should be signed or
* unsigned, etc... This is useful for formats such as WAVE where
* only 8-bit is unsigned and all other bit depths are signed.
* @return a PCM codec id or AV_CODEC_ID_NONE
*/
enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags);
/**
* Copy side data from source to destination stream
*
* @param dst pointer to destination AVStream
* @param src pointer to source AVStream
* @return >=0 on success, AVERROR code on error
*/
int ff_stream_side_data_copy(AVStream *dst, const AVStream *src);
/**
* Create a new stream and copy to it all parameters from a source stream, with
* the exception of the index field, which is set when the new stream is
* created.
*
* @param dst_ctx pointer to the context in which the new stream is created
* @param src pointer to source AVStream
* @return pointer to the new stream or NULL on error
*/
AVStream *ff_stream_clone(AVFormatContext *dst_ctx, const AVStream *src);
/**
* Wrap ffurl_move() and log if error happens.
*
* @param url_src source path
* @param url_dst destination path
* @return 0 or AVERROR on failure
*/
int ff_rename(const char *url_src, const char *url_dst, void *logctx);
/**
* Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
* which is always set to 0.
*
* Previously allocated extradata in par will be freed.
*
* @param size size of extradata
* @return 0 if OK, AVERROR_xxx on error
*/
int ff_alloc_extradata(AVCodecParameters *par, int size);
/**
* Copies the whilelists from one context to the other
*/
int ff_copy_whiteblacklists(AVFormatContext *dst, const AVFormatContext *src);
/*
* A wrapper around AVFormatContext.io_close that should be used
* instead of calling the pointer directly.
*
* @param s AVFormatContext
* @param *pb the AVIOContext to be closed and freed. Can be NULL.
* @return >=0 on success, negative AVERROR in case of failure
*/
int ff_format_io_close(AVFormatContext *s, AVIOContext **pb);
/**
* Utility function to check if the file uses http or https protocol
*
* @param s AVFormatContext
* @param filename URL or file name to open for writing
*/
int ff_is_http_proto(const char *filename);
struct AVBPrint;
/**
* Finalize buf into extradata and set its size appropriately.
*/
int ff_bprint_to_codecpar_extradata(AVCodecParameters *par, struct AVBPrint *buf);
int ff_lock_avformat(void);
int ff_unlock_avformat(void);
/**
* Set AVFormatContext url field to the provided pointer. The pointer must
* point to a valid string. The existing url field is freed if necessary. Also
* set the legacy filename field to the same string which was provided in url.
*/
void ff_format_set_url(AVFormatContext *s, char *url);
/**
* Return a positive value if the given url has one of the given
* extensions, negative AVERROR on error, 0 otherwise.
*
* @param url url to check against the given extensions
* @param extensions a comma-separated list of filename extensions
*/
int ff_match_url_ext(const char *url, const char *extensions);
struct FFOutputFormat;
struct FFInputFormat;
void avpriv_register_devices(const struct FFOutputFormat * const o[],
const struct FFInputFormat * const i[]);
#endif /* AVFORMAT_INTERNAL_H */
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