libavformat/internal.h

   1 /*
   2  * copyright (c) 2001 Fabrice Bellard
   3  *
   4  * This file is part of FFmpeg.
   5  *
   6  * FFmpeg is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10  *
  11  * FFmpeg is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with FFmpeg; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #ifndef AVFORMAT_INTERNAL_H
  22 #define AVFORMAT_INTERNAL_H
  23
  24 #include <stdint.h>
  25
  26 #include "libavutil/bprint.h"
  27 #include "avformat.h"
  28 #include "os_support.h"
  29
  30 #define MAX_URL_SIZE 4096
  31
  32 /** size of probe buffer, for guessing file type from file contents */
  33 #define PROBE_BUF_MIN 2048
  34 #define PROBE_BUF_MAX (1 << 20)
  35
  36 #ifdef DEBUG
  37 #    define hex_dump_debug(class, buf, size) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size)
  38 #else
  39 #    define hex_dump_debug(class, buf, size) do { if (0) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size); } while(0)
  40 #endif
  41
  42 typedef struct AVCodecTag {
  43     enum AVCodecID id;
  44     unsigned int tag;
  45 } AVCodecTag;
  46
  47 typedef struct CodecMime{
  48     char str[32];
  49     enum AVCodecID id;
  50 } CodecMime;
  51
  52 /*************************************************/
  53 /* fractional numbers for exact pts handling */
  54
  55 /**
  56  * The exact value of the fractional number is: 'val + num / den'.
  57  * num is assumed to be 0 <= num < den.
  58  */
  59 typedef struct FFFrac {
  60     int64_t val, num, den;
  61 } FFFrac;
  62
  63
  64 struct AVFormatInternal {
  65     /**
  66      * Number of streams relevant for interleaving.
  67      * Muxing only.
  68      */
  69     int nb_interleaved_streams;
  70
  71     /**
  72      * This buffer is only needed when packets were already buffered but
  73      * not decoded, for example to get the codec parameters in MPEG
  74      * streams.
  75      */
  76     struct AVPacketList *packet_buffer;
  77     struct AVPacketList *packet_buffer_end;
  78
  79     /* av_seek_frame() support */
  80     int64_t data_offset; /**< offset of the first packet */
  81
  82     /**
  83      * Raw packets from the demuxer, prior to parsing and decoding.
  84      * This buffer is used for buffering packets until the codec can
  85      * be identified, as parsing cannot be done without knowing the
  86      * codec.
  87      */
  88     struct AVPacketList *raw_packet_buffer;
  89     struct AVPacketList *raw_packet_buffer_end;
  90     /**
  91      * Packets split by the parser get queued here.
  92      */
  93     struct AVPacketList *parse_queue;
  94     struct AVPacketList *parse_queue_end;
  95     /**
  96      * Remaining size available for raw_packet_buffer, in bytes.
  97      */
  98 #define RAW_PACKET_BUFFER_SIZE 2500000
  99     int raw_packet_buffer_remaining_size;
 100
 101     /**
 102      * Offset to remap timestamps to be non-negative.
 103      * Expressed in timebase units.
 104      * @see AVStream.mux_ts_offset
 105      */
 106     int64_t offset;
 107
 108     /**
 109      * Timebase for the timestamp offset.
 110      */
 111     AVRational offset_timebase;
 112
 113 #if FF_API_COMPUTE_PKT_FIELDS2
 114     int missing_ts_warning;
 115 #endif
 116
 117     int inject_global_side_data;
 118
 119     int avoid_negative_ts_use_pts;
 120
 121     /**
 122      * Timestamp of the end of the shortest stream.
 123      */
 124     int64_t shortest_end;
 125
 126     /**
 127      * Whether or not avformat_init_output has already been called
 128      */
 129     int initialized;
 130
 131     /**
 132      * Whether or not avformat_init_output fully initialized streams
 133      */
 134     int streams_initialized;
 135
 136     /**
 137      * ID3v2 tag useful for MP3 demuxing
 138      */
 139     AVDictionary *id3v2_meta;
 140
 141     /*
 142      * Prefer the codec framerate for avg_frame_rate computation.
 143      */
 144     int prefer_codec_framerate;
 145 };
 146
 147 struct AVStreamInternal {
 148     /**
 149      * Set to 1 if the codec allows reordering, so pts can be different
 150      * from dts.
 151      */
 152     int reorder;
 153
 154     /**
 155      * bitstream filter to run on stream
 156      * - encoding: Set by muxer using ff_stream_add_bitstream_filter
 157      * - decoding: unused
 158      */
 159     AVBSFContext *bsfc;
 160
 161     /**
 162      * Whether or not check_bitstream should still be run on each packet
 163      */
 164     int bitstream_checked;
 165
 166     /**
 167      * The codec context used by avformat_find_stream_info, the parser, etc.
 168      */
 169     AVCodecContext *avctx;
 170     /**
 171      * 1 if avctx has been initialized with the values from the codec parameters
 172      */
 173     int avctx_inited;
 174
 175     enum AVCodecID orig_codec_id;
 176
 177     /* the context for extracting extradata in find_stream_info()
 178      * inited=1/bsf=NULL signals that extracting is not possible (codec not
 179      * supported) */
 180     struct {
 181         AVBSFContext *bsf;
 182         AVPacket     *pkt;
 183         int inited;
 184     } extract_extradata;
 185
 186     /**
 187      * Whether the internal avctx needs to be updated from codecpar (after a late change to codecpar)
 188      */
 189     int need_context_update;
 190
 191     int is_intra_only;
 192
 193     FFFrac *priv_pts;
 194 };
 195
 196 #ifdef __GNUC__
 197 #define dynarray_add(tab, nb_ptr, elem)\
 198 do {\
 199     __typeof__(tab) _tab = (tab);\
 200     __typeof__(elem) _elem = (elem);\
 201     (void)sizeof(**_tab == _elem); /* check that types are compatible */\
 202     av_dynarray_add(_tab, nb_ptr, _elem);\
 203 } while(0)
 204 #else
 205 #define dynarray_add(tab, nb_ptr, elem)\
 206 do {\
 207     av_dynarray_add((tab), nb_ptr, (elem));\
 208 } while(0)
 209 #endif
 210
 211 struct tm *ff_brktimegm(time_t secs, struct tm *tm);
 212
 213 /**
 214  * Automatically create sub-directories
 215  *
 216  * @param path will create sub-directories by path
 217  * @return 0, or < 0 on error
 218  */
 219 int ff_mkdir_p(const char *path);
 220
 221 char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
 222
 223 /**
 224  * Parse a string of hexadecimal strings. Any space between the hexadecimal
 225  * digits is ignored.
 226  *
 227  * @param data if non-null, the parsed data is written to this pointer
 228  * @param p the string to parse
 229  * @return the number of bytes written (or to be written, if data is null)
 230  */
 231 int ff_hex_to_data(uint8_t *data, const char *p);
 232
 233 /**
 234  * Add packet to an AVFormatContext's packet_buffer list, determining its
 235  * interleaved position using compare() function argument.
 236  * @return 0 on success, < 0 on error. pkt will always be blank on return.
 237  */
 238 int ff_interleave_add_packet(AVFormatContext *s, AVPacket *pkt,
 239                              int (*compare)(AVFormatContext *, const AVPacket *, const AVPacket *));
 240
 241 void ff_read_frame_flush(AVFormatContext *s);
 242
 243 #define NTP_OFFSET 2208988800ULL
 244 #define NTP_OFFSET_US (NTP_OFFSET * 1000000ULL)
 245
 246 /** Get the current time since NTP epoch in microseconds. */
 247 uint64_t ff_ntp_time(void);
 248
 249 /**
 250  * Get the NTP time stamp formatted as per the RFC-5905.
 251  *
 252  * @param ntp_time NTP time in micro seconds (since NTP epoch)
 253  * @return the formatted NTP time stamp
 254  */
 255 uint64_t ff_get_formatted_ntp_time(uint64_t ntp_time_us);
 256
 257 /**
 258  * Append the media-specific SDP fragment for the media stream c
 259  * to the buffer buff.
 260  *
 261  * Note, the buffer needs to be initialized, since it is appended to
 262  * existing content.
 263  *
 264  * @param buff the buffer to append the SDP fragment to
 265  * @param size the size of the buff buffer
 266  * @param st the AVStream of the media to describe
 267  * @param idx the global stream index
 268  * @param dest_addr the destination address of the media stream, may be NULL
 269  * @param dest_type the destination address type, may be NULL
 270  * @param port the destination port of the media stream, 0 if unknown
 271  * @param ttl the time to live of the stream, 0 if not multicast
 272  * @param fmt the AVFormatContext, which might contain options modifying
 273  *            the generated SDP
 274  */
 275 void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
 276                         const char *dest_addr, const char *dest_type,
 277                         int port, int ttl, AVFormatContext *fmt);
 278
 279 /**
 280  * Write a packet to another muxer than the one the user originally
 281  * intended. Useful when chaining muxers, where one muxer internally
 282  * writes a received packet to another muxer.
 283  *
 284  * @param dst the muxer to write the packet to
 285  * @param dst_stream the stream index within dst to write the packet to
 286  * @param pkt the packet to be written
 287  * @param src the muxer the packet originally was intended for
 288  * @param interleave 0->use av_write_frame, 1->av_interleaved_write_frame
 289  * @return the value av_write_frame returned
 290  */
 291 int ff_write_chained(AVFormatContext *dst, int dst_stream, AVPacket *pkt,
 292                      AVFormatContext *src, int interleave);
 293
 294 /**
 295  * Read a whole line of text from AVIOContext. Stop reading after reaching
 296  * either a \\n, a \\0 or EOF. The returned string is always \\0-terminated,
 297  * and may be truncated if the buffer is too small.
 298  *
 299  * @param s the read-only AVIOContext
 300  * @param buf buffer to store the read line
 301  * @param maxlen size of the buffer
 302  * @return the length of the string written in the buffer, not including the
 303  *         final \\0
 304  */
 305 int ff_get_line(AVIOContext *s, char *buf, int maxlen);
 306
 307 /**
 308  * Same as ff_get_line but strip the white-space characters in the text tail
 309  *
 310  * @param s the read-only AVIOContext
 311  * @param buf buffer to store the read line
 312  * @param maxlen size of the buffer
 313  * @return the length of the string written in the buffer
 314  */
 315 int ff_get_chomp_line(AVIOContext *s, char *buf, int maxlen);
 316
 317 /**
 318  * Read a whole line of text from AVIOContext to an AVBPrint buffer. Stop
 319  * reading after reaching a \\r, a \\n, a \\r\\n, a \\0 or EOF.  The line
 320  * ending characters are NOT included in the buffer, but they are skipped on
 321  * the input.
 322  *
 323  * @param s the read-only AVIOContext
 324  * @param bp the AVBPrint buffer
 325  * @return the length of the read line, not including the line endings,
 326  *         negative on error.
 327  */
 328 int64_t ff_read_line_to_bprint(AVIOContext *s, AVBPrint *bp);
 329
 330 /**
 331  * Read a whole line of text from AVIOContext to an AVBPrint buffer overwriting
 332  * its contents. Stop reading after reaching a \\r, a \\n, a \\r\\n, a \\0 or
 333  * EOF. The line ending characters are NOT included in the buffer, but they
 334  * are skipped on the input.
 335  *
 336  * @param s the read-only AVIOContext
 337  * @param bp the AVBPrint buffer
 338  * @return the length of the read line not including the line endings,
 339  *         negative on error, or if the buffer becomes truncated.
 340  */
 341 int64_t ff_read_line_to_bprint_overwrite(AVIOContext *s, AVBPrint *bp);
 342
 343 #define SPACE_CHARS " \t\r\n"
 344
 345 /**
 346  * Callback function type for ff_parse_key_value.
 347  *
 348  * @param key a pointer to the key
 349  * @param key_len the number of bytes that belong to the key, including the '='
 350  *                char
 351  * @param dest return the destination pointer for the value in *dest, may
 352  *             be null to ignore the value
 353  * @param dest_len the length of the *dest buffer
 354  */
 355 typedef void (*ff_parse_key_val_cb)(void *context, const char *key,
 356                                     int key_len, char **dest, int *dest_len);
 357 /**
 358  * Parse a string with comma-separated key=value pairs. The value strings
 359  * may be quoted and may contain escaped characters within quoted strings.
 360  *
 361  * @param str the string to parse
 362  * @param callback_get_buf function that returns where to store the
 363  *                         unescaped value string.
 364  * @param context the opaque context pointer to pass to callback_get_buf
 365  */
 366 void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
 367                         void *context);
 368
 369 /**
 370  * Find stream index based on format-specific stream ID
 371  * @return stream index, or < 0 on error
 372  */
 373 int ff_find_stream_index(AVFormatContext *s, int id);
 374
 375 /**
 376  * Internal version of av_index_search_timestamp
 377  */
 378 int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
 379                               int64_t wanted_timestamp, int flags);
 380
 381 /**
 382  * Internal version of av_add_index_entry
 383  */
 384 int ff_add_index_entry(AVIndexEntry **index_entries,
 385                        int *nb_index_entries,
 386                        unsigned int *index_entries_allocated_size,
 387                        int64_t pos, int64_t timestamp, int size, int distance, int flags);
 388
 389 void ff_configure_buffers_for_index(AVFormatContext *s, int64_t time_tolerance);
 390
 391 /**
 392  * Add a new chapter.
 393  *
 394  * @param s media file handle
 395  * @param id unique ID for this chapter
 396  * @param start chapter start time in time_base units
 397  * @param end chapter end time in time_base units
 398  * @param title chapter title
 399  *
 400  * @return AVChapter or NULL on error
 401  */
 402 AVChapter *avpriv_new_chapter(AVFormatContext *s, int id, AVRational time_base,
 403                               int64_t start, int64_t end, const char *title);
 404
 405 /**
 406  * Ensure the index uses less memory than the maximum specified in
 407  * AVFormatContext.max_index_size by discarding entries if it grows
 408  * too large.
 409  */
 410 void ff_reduce_index(AVFormatContext *s, int stream_index);
 411
 412 enum AVCodecID ff_guess_image2_codec(const char *filename);
 413
 414 /**
 415  * Perform a binary search using av_index_search_timestamp() and
 416  * AVInputFormat.read_timestamp().
 417  *
 418  * @param target_ts target timestamp in the time base of the given stream
 419  * @param stream_index stream number
 420  */
 421 int ff_seek_frame_binary(AVFormatContext *s, int stream_index,
 422                          int64_t target_ts, int flags);
 423
 424 /**
 425  * Update cur_dts of all streams based on the given timestamp and AVStream.
 426  *
 427  * Stream ref_st unchanged, others set cur_dts in their native time base.
 428  * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
 429  * @param timestamp new dts expressed in time_base of param ref_st
 430  * @param ref_st reference stream giving time_base of param timestamp
 431  */
 432 void ff_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
 433
 434 int ff_find_last_ts(AVFormatContext *s, int stream_index, int64_t *ts, int64_t *pos,
 435                     int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
 436
 437 /**
 438  * Perform a binary search using read_timestamp().
 439  *
 440  * @param target_ts target timestamp in the time base of the given stream
 441  * @param stream_index stream number
 442  */
 443 int64_t ff_gen_search(AVFormatContext *s, int stream_index,
 444                       int64_t target_ts, int64_t pos_min,
 445                       int64_t pos_max, int64_t pos_limit,
 446                       int64_t ts_min, int64_t ts_max,
 447                       int flags, int64_t *ts_ret,
 448                       int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
 449
 450 /**
 451  * Set the time base and wrapping info for a given stream. This will be used
 452  * to interpret the stream's timestamps. If the new time base is invalid
 453  * (numerator or denominator are non-positive), it leaves the stream
 454  * unchanged.
 455  *
 456  * @param s stream
 457  * @param pts_wrap_bits number of bits effectively used by the pts
 458  *        (used for wrap control)
 459  * @param pts_num time base numerator
 460  * @param pts_den time base denominator
 461  */
 462 void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits,
 463                          unsigned int pts_num, unsigned int pts_den);
 464
 465 /**
 466  * Add side data to a packet for changing parameters to the given values.
 467  * Parameters set to 0 aren't included in the change.
 468  */
 469 int ff_add_param_change(AVPacket *pkt, int32_t channels,
 470                         uint64_t channel_layout, int32_t sample_rate,
 471                         int32_t width, int32_t height);
 472
 473 /**
 474  * Set the timebase for each stream from the corresponding codec timebase and
 475  * print it.
 476  */
 477 int ff_framehash_write_header(AVFormatContext *s);
 478
 479 /**
 480  * Read a transport packet from a media file.
 481  *
 482  * @param s media file handle
 483  * @param pkt is filled
 484  * @return 0 if OK, AVERROR_xxx on error
 485  */
 486 int ff_read_packet(AVFormatContext *s, AVPacket *pkt);
 487
 488 /**
 489  * Interleave an AVPacket per dts so it can be muxed.
 490  *
 491  * @param s   an AVFormatContext for output. pkt resp. out will be added to
 492  *            resp. taken from its packet buffer.
 493  * @param out the interleaved packet will be output here
 494  * @param pkt the input packet; will be blank on return if not NULL
 495  * @param flush 1 if no further packets are available as input and all
 496  *              remaining packets should be output
 497  * @return 1 if a packet was output, 0 if no packet could be output
 498  *         (in which case out may be uninitialized), < 0 if an error occurred
 499  */
 500 int ff_interleave_packet_per_dts(AVFormatContext *s, AVPacket *out,
 501                                  AVPacket *pkt, int flush);
 502
 503 void ff_free_stream(AVFormatContext *s, AVStream *st);
 504
 505 /**
 506  * Return the frame duration in seconds. Return 0 if not available.
 507  */
 508 void ff_compute_frame_duration(AVFormatContext *s, int *pnum, int *pden, AVStream *st,
 509                                AVCodecParserContext *pc, AVPacket *pkt);
 510
 511 unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id);
 512
 513 enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag);
 514
 515 int ff_is_intra_only(enum AVCodecID id);
 516
 517 /**
 518  * Select a PCM codec based on the given parameters.
 519  *
 520  * @param bps     bits-per-sample
 521  * @param flt     floating-point
 522  * @param be      big-endian
 523  * @param sflags  signed flags. each bit corresponds to one byte of bit depth.
 524  *                e.g. the 1st bit indicates if 8-bit should be signed or
 525  *                unsigned, the 2nd bit indicates if 16-bit should be signed or
 526  *                unsigned, etc... This is useful for formats such as WAVE where
 527  *                only 8-bit is unsigned and all other bit depths are signed.
 528  * @return        a PCM codec id or AV_CODEC_ID_NONE
 529  */
 530 enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags);
 531
 532 /**
 533  * Chooses a timebase for muxing the specified stream.
 534  *
 535  * The chosen timebase allows sample accurate timestamps based
 536  * on the framerate or sample rate for audio streams. It also is
 537  * at least as precise as 1/min_precision would be.
 538  */
 539 AVRational ff_choose_timebase(AVFormatContext *s, AVStream *st, int min_precision);
 540
 541 /**
 542  * Chooses a timebase for muxing the specified stream.
 543  */
 544 enum AVChromaLocation ff_choose_chroma_location(AVFormatContext *s, AVStream *st);
 545
 546 /**
 547  * Generate standard extradata for AVC-Intra based on width/height and field
 548  * order.
 549  */
 550 int ff_generate_avci_extradata(AVStream *st);
 551
 552 /**
 553  * Add a bitstream filter to a stream.
 554  *
 555  * @param st output stream to add a filter to
 556  * @param name the name of the filter to add
 557  * @param args filter-specific argument string
 558  * @return  >0 on success;
 559  *          AVERROR code on failure
 560  */
 561 int ff_stream_add_bitstream_filter(AVStream *st, const char *name, const char *args);
 562
 563 /**
 564  * Copy encoding parameters from source to destination stream
 565  *
 566  * @param dst pointer to destination AVStream
 567  * @param src pointer to source AVStream
 568  * @return >=0 on success, AVERROR code on error
 569  */
 570 int ff_stream_encode_params_copy(AVStream *dst, const AVStream *src);
 571
 572 /**
 573  * Wrap avpriv_io_move and log if error happens.
 574  *
 575  * @param url_src source path
 576  * @param url_dst destination path
 577  * @return        0 or AVERROR on failure
 578  */
 579 int ff_rename(const char *url_src, const char *url_dst, void *logctx);
 580
 581 /**
 582  * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
 583  * which is always set to 0.
 584  *
 585  * Previously allocated extradata in par will be freed.
 586  *
 587  * @param size size of extradata
 588  * @return 0 if OK, AVERROR_xxx on error
 589  */
 590 int ff_alloc_extradata(AVCodecParameters *par, int size);
 591
 592 /**
 593  * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
 594  * which is always set to 0 and fill it from pb.
 595  *
 596  * @param size size of extradata
 597  * @return >= 0 if OK, AVERROR_xxx on error
 598  */
 599 int ff_get_extradata(AVFormatContext *s, AVCodecParameters *par, AVIOContext *pb, int size);
 600
 601 /**
 602  * add frame for rfps calculation.
 603  *
 604  * @param dts timestamp of the i-th frame
 605  * @return 0 if OK, AVERROR_xxx on error
 606  */
 607 int ff_rfps_add_frame(AVFormatContext *ic, AVStream *st, int64_t dts);
 608
 609 void ff_rfps_calculate(AVFormatContext *ic);
 610
 611 /**
 612  * Flags for AVFormatContext.write_uncoded_frame()
 613  */
 614 enum AVWriteUncodedFrameFlags {
 615
 616     /**
 617      * Query whether the feature is possible on this stream.
 618      * The frame argument is ignored.
 619      */
 620     AV_WRITE_UNCODED_FRAME_QUERY           = 0x0001,
 621
 622 };
 623
 624 /**
 625  * Copies the whilelists from one context to the other
 626  */
 627 int ff_copy_whiteblacklists(AVFormatContext *dst, const AVFormatContext *src);
 628
 629 /**
 630  * Returned by demuxers to indicate that data was consumed but discarded
 631  * (ignored streams or junk data). The framework will re-call the demuxer.
 632  */
 633 #define FFERROR_REDO FFERRTAG('R','E','D','O')
 634
 635 /**
 636  * Utility function to open IO stream of output format.
 637  *
 638  * @param s AVFormatContext
 639  * @param url URL or file name to open for writing
 640  * @options optional options which will be passed to io_open callback
 641  * @return >=0 on success, negative AVERROR in case of failure
 642  */
 643 int ff_format_output_open(AVFormatContext *s, const char *url, AVDictionary **options);
 644
 645 /*
 646  * A wrapper around AVFormatContext.io_close that should be used
 647  * instead of calling the pointer directly.
 648  */
 649 void ff_format_io_close(AVFormatContext *s, AVIOContext **pb);
 650
 651 /**
 652  * Utility function to check if the file uses http or https protocol
 653  *
 654  * @param s AVFormatContext
 655  * @param filename URL or file name to open for writing
 656  */
 657 int ff_is_http_proto(char *filename);
 658
 659 /**
 660  * Parse creation_time in AVFormatContext metadata if exists and warn if the
 661  * parsing fails.
 662  *
 663  * @param s AVFormatContext
 664  * @param timestamp parsed timestamp in microseconds, only set on successful parsing
 665  * @param return_seconds set this to get the number of seconds in timestamp instead of microseconds
 666  * @return 1 if OK, 0 if the metadata was not present, AVERROR(EINVAL) on parse error
 667  */
 668 int ff_parse_creation_time_metadata(AVFormatContext *s, int64_t *timestamp, int return_seconds);
 669
 670 /**
 671  * Standardize creation_time metadata in AVFormatContext to an ISO-8601
 672  * timestamp string.
 673  *
 674  * @param s AVFormatContext
 675  * @return <0 on error
 676  */
 677 int ff_standardize_creation_time(AVFormatContext *s);
 678
 679 #define CONTAINS_PAL 2
 680 /**
 681  * Reshuffles the lines to use the user specified stride.
 682  *
 683  * @param ppkt input and output packet
 684  * @return negative error code or
 685  *         0 if no new packet was allocated
 686  *         non-zero if a new packet was allocated and ppkt has to be freed
 687  *         CONTAINS_PAL if in addition to a new packet the old contained a palette
 688  */
 689 int ff_reshuffle_raw_rgb(AVFormatContext *s, AVPacket **ppkt, AVCodecParameters *par, int expected_stride);
 690
 691 /**
 692  * Retrieves the palette from a packet, either from side data, or
 693  * appended to the video data in the packet itself (raw video only).
 694  * It is commonly used after a call to ff_reshuffle_raw_rgb().
 695  *
 696  * Use 0 for the ret parameter to check for side data only.
 697  *
 698  * @param pkt pointer to packet before calling ff_reshuffle_raw_rgb()
 699  * @param ret return value from ff_reshuffle_raw_rgb(), or 0
 700  * @param palette pointer to palette buffer
 701  * @return negative error code or
 702  *         1 if the packet has a palette, else 0
 703  */
 704 int ff_get_packet_palette(AVFormatContext *s, AVPacket *pkt, int ret, uint32_t *palette);
 705
 706 /**
 707  * Finalize buf into extradata and set its size appropriately.
 708  */
 709 int ff_bprint_to_codecpar_extradata(AVCodecParameters *par, struct AVBPrint *buf);
 710
 711 /**
 712  * Find the next packet in the interleaving queue for the given stream.
 713  * The pkt parameter is filled in with the queued packet, including
 714  * references to the data (which the caller is not allowed to keep or
 715  * modify).
 716  *
 717  * @return 0 if a packet was found, a negative value if no packet was found
 718  */
 719 int ff_interleaved_peek(AVFormatContext *s, int stream,
 720                         AVPacket *pkt, int add_offset);
 721
 722
 723 int ff_lock_avformat(void);
 724 int ff_unlock_avformat(void);
 725
 726 /**
 727  * Set AVFormatContext url field to the provided pointer. The pointer must
 728  * point to a valid string. The existing url field is freed if necessary. Also
 729  * set the legacy filename field to the same string which was provided in url.
 730  */
 731 void ff_format_set_url(AVFormatContext *s, char *url);
 732
 733 /**
 734  * Return a positive value if the given url has one of the given
 735  * extensions, negative AVERROR on error, 0 otherwise.
 736  *
 737  * @param url        url to check against the given extensions
 738  * @param extensions a comma-separated list of filename extensions
 739  */
 740 int ff_match_url_ext(const char *url, const char *extensions);
 741
 742 #define FF_PACKETLIST_FLAG_REF_PACKET (1 << 0) /**< Create a new reference for the packet instead of
 743                                                     transferring the ownership of the existing one to the
 744                                                     list. */
 745
 746 /**
 747  * Append an AVPacket to the list.
 748  *
 749  * @param head  List head element
 750  * @param tail  List tail element
 751  * @param pkt   The packet being appended. The data described in it will
 752  *              be made reference counted if it isn't already.
 753  * @param flags Any combination of FF_PACKETLIST_FLAG_* flags
 754  * @return 0 on success, negative AVERROR value on failure. On failure,
 755            the list is unchanged
 756  */
 757 int ff_packet_list_put(AVPacketList **head, AVPacketList **tail,
 758                        AVPacket *pkt, int flags);
 759
 760 /**
 761  * Remove the oldest AVPacket in the list and return it.
 762  * The behaviour is undefined if the packet list is empty.
 763  *
 764  * @note The pkt will be overwritten completely. The caller owns the
 765  *       packet and must unref it by itself.
 766  *
 767  * @param head List head element
 768  * @param tail List tail element
 769  * @param pkt  Pointer to an AVPacket struct
 770  * @return 0 on success. Success is guaranteed
 771  *         if the packet list is not empty.
 772  */
 773 int ff_packet_list_get(AVPacketList **head, AVPacketList **tail,
 774                        AVPacket *pkt);
 775
 776 /**
 777  * Wipe the list and unref all the packets in it.
 778  *
 779  * @param head List head element
 780  * @param tail List tail element
 781  */
 782 void ff_packet_list_free(AVPacketList **head, AVPacketList **tail);
 783
 784 void avpriv_register_devices(const AVOutputFormat * const o[], const AVInputFormat * const i[]);
 785
 786 #endif /* AVFORMAT_INTERNAL_H */