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internal.h
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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 #include "avformat.h"
26 #include "os_support.h"
27 
28 #define MAX_URL_SIZE 4096
29 
30 /** size of probe buffer, for guessing file type from file contents */
31 #define PROBE_BUF_MIN 2048
32 #define PROBE_BUF_MAX (1 << 20)
33 
34 #ifdef DEBUG
35 # define hex_dump_debug(class, buf, size) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size)
36 #else
37 # define hex_dump_debug(class, buf, size)
38 #endif
39 
40 typedef struct AVCodecTag {
41  enum AVCodecID id;
42  unsigned int tag;
43 } AVCodecTag;
44 
45 typedef struct CodecMime{
46  char str[32];
47  enum AVCodecID id;
48 } CodecMime;
49 
51  /**
52  * Number of streams relevant for interleaving.
53  * Muxing only.
54  */
56 
58 };
59 
60 #ifdef __GNUC__
61 #define dynarray_add(tab, nb_ptr, elem)\
62 do {\
63  __typeof__(tab) _tab = (tab);\
64  __typeof__(elem) _elem = (elem);\
65  (void)sizeof(**_tab == _elem); /* check that types are compatible */\
66  av_dynarray_add(_tab, nb_ptr, _elem);\
67 } while(0)
68 #else
69 #define dynarray_add(tab, nb_ptr, elem)\
70 do {\
71  av_dynarray_add((tab), nb_ptr, (elem));\
72 } while(0)
73 #endif
74 
75 struct tm *ff_brktimegm(time_t secs, struct tm *tm);
76 
77 char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
78 
79 /**
80  * Parse a string of hexadecimal strings. Any space between the hexadecimal
81  * digits is ignored.
82  *
83  * @param data if non-null, the parsed data is written to this pointer
84  * @param p the string to parse
85  * @return the number of bytes written (or to be written, if data is null)
86  */
87 int ff_hex_to_data(uint8_t *data, const char *p);
88 
89 void ff_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
90 
91 /**
92  * Add packet to AVFormatContext->packet_buffer list, determining its
93  * interleaved position using compare() function argument.
94  * @return 0, or < 0 on error
95  */
97  int (*compare)(AVFormatContext *, AVPacket *, AVPacket *));
98 
100 
101 #define NTP_OFFSET 2208988800ULL
102 #define NTP_OFFSET_US (NTP_OFFSET * 1000000ULL)
103 
104 /** Get the current time since NTP epoch in microseconds. */
105 uint64_t ff_ntp_time(void);
106 
107 /**
108  * Append the media-specific SDP fragment for the media stream c
109  * to the buffer buff.
110  *
111  * Note, the buffer needs to be initialized, since it is appended to
112  * existing content.
113  *
114  * @param buff the buffer to append the SDP fragment to
115  * @param size the size of the buff buffer
116  * @param st the AVStream of the media to describe
117  * @param idx the global stream index
118  * @param dest_addr the destination address of the media stream, may be NULL
119  * @param dest_type the destination address type, may be NULL
120  * @param port the destination port of the media stream, 0 if unknown
121  * @param ttl the time to live of the stream, 0 if not multicast
122  * @param fmt the AVFormatContext, which might contain options modifying
123  * the generated SDP
124  */
125 void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
126  const char *dest_addr, const char *dest_type,
127  int port, int ttl, AVFormatContext *fmt);
128 
129 /**
130  * Write a packet to another muxer than the one the user originally
131  * intended. Useful when chaining muxers, where one muxer internally
132  * writes a received packet to another muxer.
133  *
134  * @param dst the muxer to write the packet to
135  * @param dst_stream the stream index within dst to write the packet to
136  * @param pkt the packet to be written
137  * @param src the muxer the packet originally was intended for
138  * @param interleave 0->use av_write_frame, 1->av_write_interleaved_frame
139  * @return the value av_write_frame returned
140  */
141 int ff_write_chained(AVFormatContext *dst, int dst_stream, AVPacket *pkt,
143 
144 /**
145  * Get the length in bytes which is needed to store val as v.
146  */
147 int ff_get_v_length(uint64_t val);
148 
149 /**
150  * Put val using a variable number of bytes.
151  */
152 void ff_put_v(AVIOContext *bc, uint64_t val);
153 
154 /**
155  * Read a whole line of text from AVIOContext. Stop reading after reaching
156  * either a \\n, a \\0 or EOF. The returned string is always \\0-terminated,
157  * and may be truncated if the buffer is too small.
158  *
159  * @param s the read-only AVIOContext
160  * @param buf buffer to store the read line
161  * @param maxlen size of the buffer
162  * @return the length of the string written in the buffer, not including the
163  * final \\0
164  */
165 int ff_get_line(AVIOContext *s, char *buf, int maxlen);
166 
167 #define SPACE_CHARS " \t\r\n"
168 
169 /**
170  * Callback function type for ff_parse_key_value.
171  *
172  * @param key a pointer to the key
173  * @param key_len the number of bytes that belong to the key, including the '='
174  * char
175  * @param dest return the destination pointer for the value in *dest, may
176  * be null to ignore the value
177  * @param dest_len the length of the *dest buffer
178  */
179 typedef void (*ff_parse_key_val_cb)(void *context, const char *key,
180  int key_len, char **dest, int *dest_len);
181 /**
182  * Parse a string with comma-separated key=value pairs. The value strings
183  * may be quoted and may contain escaped characters within quoted strings.
184  *
185  * @param str the string to parse
186  * @param callback_get_buf function that returns where to store the
187  * unescaped value string.
188  * @param context the opaque context pointer to pass to callback_get_buf
189  */
190 void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
191  void *context);
192 
193 /**
194  * Find stream index based on format-specific stream ID
195  * @return stream index, or < 0 on error
196  */
197 int ff_find_stream_index(AVFormatContext *s, int id);
198 
199 /**
200  * Internal version of av_index_search_timestamp
201  */
202 int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
203  int64_t wanted_timestamp, int flags);
204 
205 /**
206  * Internal version of av_add_index_entry
207  */
208 int ff_add_index_entry(AVIndexEntry **index_entries,
209  int *nb_index_entries,
210  unsigned int *index_entries_allocated_size,
211  int64_t pos, int64_t timestamp, int size, int distance, int flags);
212 
213 /**
214  * Add a new chapter.
215  *
216  * @param s media file handle
217  * @param id unique ID for this chapter
218  * @param start chapter start time in time_base units
219  * @param end chapter end time in time_base units
220  * @param title chapter title
221  *
222  * @return AVChapter or NULL on error
223  */
225  int64_t start, int64_t end, const char *title);
226 
227 /**
228  * Ensure the index uses less memory than the maximum specified in
229  * AVFormatContext.max_index_size by discarding entries if it grows
230  * too large.
231  */
232 void ff_reduce_index(AVFormatContext *s, int stream_index);
233 
234 enum AVCodecID ff_guess_image2_codec(const char *filename);
235 
236 /**
237  * Convert a date string in ISO8601 format to Unix timestamp.
238  */
239 int64_t ff_iso8601_to_unix_time(const char *datestr);
240 
241 /**
242  * Perform a binary search using av_index_search_timestamp() and
243  * AVInputFormat.read_timestamp().
244  *
245  * @param target_ts target timestamp in the time base of the given stream
246  * @param stream_index stream number
247  */
248 int ff_seek_frame_binary(AVFormatContext *s, int stream_index,
249  int64_t target_ts, int flags);
250 
251 /**
252  * Update cur_dts of all streams based on the given timestamp and AVStream.
253  *
254  * Stream ref_st unchanged, others set cur_dts in their native time base.
255  * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
256  * @param timestamp new dts expressed in time_base of param ref_st
257  * @param ref_st reference stream giving time_base of param timestamp
258  */
259 void ff_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
260 
261 int ff_find_last_ts(AVFormatContext *s, int stream_index, int64_t *ts, int64_t *pos,
262  int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
263 
264 /**
265  * Perform a binary search using read_timestamp().
266  *
267  * @param target_ts target timestamp in the time base of the given stream
268  * @param stream_index stream number
269  */
270 int64_t ff_gen_search(AVFormatContext *s, int stream_index,
271  int64_t target_ts, int64_t pos_min,
272  int64_t pos_max, int64_t pos_limit,
273  int64_t ts_min, int64_t ts_max,
274  int flags, int64_t *ts_ret,
275  int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
276 
277 /**
278  * Set the time base and wrapping info for a given stream. This will be used
279  * to interpret the stream's timestamps. If the new time base is invalid
280  * (numerator or denominator are non-positive), it leaves the stream
281  * unchanged.
282  *
283  * @param s stream
284  * @param pts_wrap_bits number of bits effectively used by the pts
285  * (used for wrap control)
286  * @param pts_num time base numerator
287  * @param pts_den time base denominator
288  */
289 void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits,
290  unsigned int pts_num, unsigned int pts_den);
291 
292 /**
293  * Add side data to a packet for changing parameters to the given values.
294  * Parameters set to 0 aren't included in the change.
295  */
296 int ff_add_param_change(AVPacket *pkt, int32_t channels,
297  uint64_t channel_layout, int32_t sample_rate,
299 
300 /**
301  * Set the timebase for each stream from the corresponding codec timebase and
302  * print it.
303  */
305 
306 /**
307  * Read a transport packet from a media file.
308  *
309  * @param s media file handle
310  * @param pkt is filled
311  * @return 0 if OK, AVERROR_xxx on error
312  */
314 
315 /**
316  * Interleave a packet per dts in an output media file.
317  *
318  * Packets with pkt->destruct == av_destruct_packet will be freed inside this
319  * function, so they cannot be used after it. Note that calling av_free_packet()
320  * on them is still safe.
321  *
322  * @param s media file handle
323  * @param out the interleaved packet will be output here
324  * @param pkt the input packet
325  * @param flush 1 if no further packets are available as input and all
326  * remaining packets should be output
327  * @return 1 if a packet was output, 0 if no packet could be output,
328  * < 0 if an error occurred
329  */
331  AVPacket *pkt, int flush);
332 
334 
335 /**
336  * Return the frame duration in seconds. Return 0 if not available.
337  */
338 void ff_compute_frame_duration(AVFormatContext *s, int *pnum, int *pden, AVStream *st,
339  AVCodecParserContext *pc, AVPacket *pkt);
340 
341 unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id);
342 
343 enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag);
344 
345 /**
346  * Select a PCM codec based on the given parameters.
347  *
348  * @param bps bits-per-sample
349  * @param flt floating-point
350  * @param be big-endian
351  * @param sflags signed flags. each bit corresponds to one byte of bit depth.
352  * e.g. the 1st bit indicates if 8-bit should be signed or
353  * unsigned, the 2nd bit indicates if 16-bit should be signed or
354  * unsigned, etc... This is useful for formats such as WAVE where
355  * only 8-bit is unsigned and all other bit depths are signed.
356  * @return a PCM codec id or AV_CODEC_ID_NONE
357  */
358 enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags);
359 
360 /**
361  * Chooses a timebase for muxing the specified stream.
362  *
363  * The chosen timebase allows sample accurate timestamps based
364  * on the framerate or sample rate for audio streams. It also is
365  * at least as precise as 1/min_precision would be.
366  */
367 AVRational ff_choose_timebase(AVFormatContext *s, AVStream *st, int min_precision);
368 
369 /**
370  * Generate standard extradata for AVC-Intra based on width/height and field
371  * order.
372  */
374 
375 /**
376  * Wrap errno on rename() error.
377  *
378  * @param oldpath source path
379  * @param newpath destination path
380  * @return 0 or AVERROR on failure
381  */
382 static inline int ff_rename(const char *oldpath, const char *newpath, void *logctx)
383 {
384  int ret = 0;
385  if (rename(oldpath, newpath) == -1) {
386  ret = AVERROR(errno);
387  if (logctx)
388  av_log(logctx, AV_LOG_ERROR, "failed to rename file %s to %s\n", oldpath, newpath);
389  }
390  return ret;
391 }
392 
393 /**
394  * Add new side data to a stream. If a side data of this type already exists, it
395  * is replaced.
396  */
398  int size);
399 
400 /**
401  * Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end
402  * which is always set to 0.
403  *
404  * @param size size of extradata
405  * @return 0 if OK, AVERROR_xxx on error
406  */
407 int ff_alloc_extradata(AVCodecContext *avctx, int size);
408 
409 /**
410  * Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end
411  * which is always set to 0 and fill it from pb.
412  *
413  * @param size size of extradata
414  * @return >= 0 if OK, AVERROR_xxx on error
415  */
416 int ff_get_extradata(AVCodecContext *avctx, AVIOContext *pb, int size);
417 
418 /**
419  * add frame for rfps calculation.
420  *
421  * @param dts timestamp of the i-th frame
422  * @return 0 if OK, AVERROR_xxx on error
423  */
424 int ff_rfps_add_frame(AVFormatContext *ic, AVStream *st, int64_t dts);
425 
427 
428 /**
429  * Flags for AVFormatContext.write_uncoded_frame()
430  */
432 
433  /**
434  * Query whether the feature is possible on this stream.
435  * The frame argument is ignored.
436  */
438 
439 };
440 
441 /**
442  * Copies the whilelists from one context to the other
443  */
445 
446 #endif /* AVFORMAT_INTERNAL_H */