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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 
27 #define MAX_URL_SIZE 4096
28 
29 /** size of probe buffer, for guessing file type from file contents */
30 #define PROBE_BUF_MIN 2048
31 #define PROBE_BUF_MAX (1 << 20)
32 
33 #ifdef DEBUG
34 # define hex_dump_debug(class, buf, size) av_hex_dump_log(class, AV_LOG_DEBUG, buf, size)
35 #else
36 # define hex_dump_debug(class, buf, size)
37 #endif
38 
39 typedef struct AVCodecTag {
40  enum AVCodecID id;
41  unsigned int tag;
42 } AVCodecTag;
43 
44 typedef struct CodecMime{
45  char str[32];
46  enum AVCodecID id;
47 } CodecMime;
48 
50  /**
51  * Number of streams relevant for interleaving.
52  * Muxing only.
53  */
55 
57 };
58 
59 #ifdef __GNUC__
60 #define dynarray_add(tab, nb_ptr, elem)\
61 do {\
62  __typeof__(tab) _tab = (tab);\
63  __typeof__(elem) _elem = (elem);\
64  (void)sizeof(**_tab == _elem); /* check that types are compatible */\
65  av_dynarray_add(_tab, nb_ptr, _elem);\
66 } while(0)
67 #else
68 #define dynarray_add(tab, nb_ptr, elem)\
69 do {\
70  av_dynarray_add((tab), nb_ptr, (elem));\
71 } while(0)
72 #endif
73 
74 struct tm *ff_brktimegm(time_t secs, struct tm *tm);
75 
76 char *ff_data_to_hex(char *buf, const uint8_t *src, int size, int lowercase);
77 
78 /**
79  * Parse a string of hexadecimal strings. Any space between the hexadecimal
80  * digits is ignored.
81  *
82  * @param data if non-null, the parsed data is written to this pointer
83  * @param p the string to parse
84  * @return the number of bytes written (or to be written, if data is null)
85  */
86 int ff_hex_to_data(uint8_t *data, const char *p);
87 
88 void ff_program_add_stream_index(AVFormatContext *ac, int progid, unsigned int idx);
89 
90 /**
91  * Add packet to AVFormatContext->packet_buffer list, determining its
92  * interleaved position using compare() function argument.
93  * @return 0, or < 0 on error
94  */
96  int (*compare)(AVFormatContext *, AVPacket *, AVPacket *));
97 
99 
100 #define NTP_OFFSET 2208988800ULL
101 #define NTP_OFFSET_US (NTP_OFFSET * 1000000ULL)
102 
103 /** Get the current time since NTP epoch in microseconds. */
104 uint64_t ff_ntp_time(void);
105 
106 /**
107  * Append the media-specific SDP fragment for the media stream c
108  * to the buffer buff.
109  *
110  * Note, the buffer needs to be initialized, since it is appended to
111  * existing content.
112  *
113  * @param buff the buffer to append the SDP fragment to
114  * @param size the size of the buff buffer
115  * @param st the AVStream of the media to describe
116  * @param idx the global stream index
117  * @param dest_addr the destination address of the media stream, may be NULL
118  * @param dest_type the destination address type, may be NULL
119  * @param port the destination port of the media stream, 0 if unknown
120  * @param ttl the time to live of the stream, 0 if not multicast
121  * @param fmt the AVFormatContext, which might contain options modifying
122  * the generated SDP
123  */
124 void ff_sdp_write_media(char *buff, int size, AVStream *st, int idx,
125  const char *dest_addr, const char *dest_type,
126  int port, int ttl, AVFormatContext *fmt);
127 
128 /**
129  * Write a packet to another muxer than the one the user originally
130  * intended. Useful when chaining muxers, where one muxer internally
131  * writes a received packet to another muxer.
132  *
133  * @param dst the muxer to write the packet to
134  * @param dst_stream the stream index within dst to write the packet to
135  * @param pkt the packet to be written
136  * @param src the muxer the packet originally was intended for
137  * @param interleave 0->use av_write_frame, 1->av_write_interleaved_frame
138  * @return the value av_write_frame returned
139  */
140 int ff_write_chained(AVFormatContext *dst, int dst_stream, AVPacket *pkt,
142 
143 /**
144  * Get the length in bytes which is needed to store val as v.
145  */
146 int ff_get_v_length(uint64_t val);
147 
148 /**
149  * Put val using a variable number of bytes.
150  */
151 void ff_put_v(AVIOContext *bc, uint64_t val);
152 
153 /**
154  * Read a whole line of text from AVIOContext. Stop reading after reaching
155  * either a \\n, a \\0 or EOF. The returned string is always \\0-terminated,
156  * and may be truncated if the buffer is too small.
157  *
158  * @param s the read-only AVIOContext
159  * @param buf buffer to store the read line
160  * @param maxlen size of the buffer
161  * @return the length of the string written in the buffer, not including the
162  * final \\0
163  */
164 int ff_get_line(AVIOContext *s, char *buf, int maxlen);
165 
166 #define SPACE_CHARS " \t\r\n"
167 
168 /**
169  * Callback function type for ff_parse_key_value.
170  *
171  * @param key a pointer to the key
172  * @param key_len the number of bytes that belong to the key, including the '='
173  * char
174  * @param dest return the destination pointer for the value in *dest, may
175  * be null to ignore the value
176  * @param dest_len the length of the *dest buffer
177  */
178 typedef void (*ff_parse_key_val_cb)(void *context, const char *key,
179  int key_len, char **dest, int *dest_len);
180 /**
181  * Parse a string with comma-separated key=value pairs. The value strings
182  * may be quoted and may contain escaped characters within quoted strings.
183  *
184  * @param str the string to parse
185  * @param callback_get_buf function that returns where to store the
186  * unescaped value string.
187  * @param context the opaque context pointer to pass to callback_get_buf
188  */
189 void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
190  void *context);
191 
192 /**
193  * Find stream index based on format-specific stream ID
194  * @return stream index, or < 0 on error
195  */
196 int ff_find_stream_index(AVFormatContext *s, int id);
197 
198 /**
199  * Internal version of av_index_search_timestamp
200  */
201 int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
202  int64_t wanted_timestamp, int flags);
203 
204 /**
205  * Internal version of av_add_index_entry
206  */
207 int ff_add_index_entry(AVIndexEntry **index_entries,
208  int *nb_index_entries,
209  unsigned int *index_entries_allocated_size,
210  int64_t pos, int64_t timestamp, int size, int distance, int flags);
211 
212 /**
213  * Add a new chapter.
214  *
215  * @param s media file handle
216  * @param id unique ID for this chapter
217  * @param start chapter start time in time_base units
218  * @param end chapter end time in time_base units
219  * @param title chapter title
220  *
221  * @return AVChapter or NULL on error
222  */
224  int64_t start, int64_t end, const char *title);
225 
226 /**
227  * Ensure the index uses less memory than the maximum specified in
228  * AVFormatContext.max_index_size by discarding entries if it grows
229  * too large.
230  */
231 void ff_reduce_index(AVFormatContext *s, int stream_index);
232 
233 enum AVCodecID ff_guess_image2_codec(const char *filename);
234 
235 /**
236  * Convert a date string in ISO8601 format to Unix timestamp.
237  */
238 int64_t ff_iso8601_to_unix_time(const char *datestr);
239 
240 /**
241  * Perform a binary search using av_index_search_timestamp() and
242  * AVInputFormat.read_timestamp().
243  *
244  * @param target_ts target timestamp in the time base of the given stream
245  * @param stream_index stream number
246  */
247 int ff_seek_frame_binary(AVFormatContext *s, int stream_index,
248  int64_t target_ts, int flags);
249 
250 /**
251  * Update cur_dts of all streams based on the given timestamp and AVStream.
252  *
253  * Stream ref_st unchanged, others set cur_dts in their native time base.
254  * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
255  * @param timestamp new dts expressed in time_base of param ref_st
256  * @param ref_st reference stream giving time_base of param timestamp
257  */
258 void ff_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
259 
260 int ff_find_last_ts(AVFormatContext *s, int stream_index, int64_t *ts, int64_t *pos,
261  int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
262 
263 /**
264  * Perform a binary search using read_timestamp().
265  *
266  * @param target_ts target timestamp in the time base of the given stream
267  * @param stream_index stream number
268  */
269 int64_t ff_gen_search(AVFormatContext *s, int stream_index,
270  int64_t target_ts, int64_t pos_min,
271  int64_t pos_max, int64_t pos_limit,
272  int64_t ts_min, int64_t ts_max,
273  int flags, int64_t *ts_ret,
274  int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
275 
276 /**
277  * Set the time base and wrapping info for a given stream. This will be used
278  * to interpret the stream's timestamps. If the new time base is invalid
279  * (numerator or denominator are non-positive), it leaves the stream
280  * unchanged.
281  *
282  * @param s stream
283  * @param pts_wrap_bits number of bits effectively used by the pts
284  * (used for wrap control)
285  * @param pts_num time base numerator
286  * @param pts_den time base denominator
287  */
288 void avpriv_set_pts_info(AVStream *s, int pts_wrap_bits,
289  unsigned int pts_num, unsigned int pts_den);
290 
291 /**
292  * Add side data to a packet for changing parameters to the given values.
293  * Parameters set to 0 aren't included in the change.
294  */
295 int ff_add_param_change(AVPacket *pkt, int32_t channels,
296  uint64_t channel_layout, int32_t sample_rate,
298 
299 /**
300  * Set the timebase for each stream from the corresponding codec timebase and
301  * print it.
302  */
304 
305 /**
306  * Read a transport packet from a media file.
307  *
308  * @param s media file handle
309  * @param pkt is filled
310  * @return 0 if OK, AVERROR_xxx on error
311  */
313 
314 /**
315  * Interleave a packet per dts in an output media file.
316  *
317  * Packets with pkt->destruct == av_destruct_packet will be freed inside this
318  * function, so they cannot be used after it. Note that calling av_free_packet()
319  * on them is still safe.
320  *
321  * @param s media file handle
322  * @param out the interleaved packet will be output here
323  * @param pkt the input packet
324  * @param flush 1 if no further packets are available as input and all
325  * remaining packets should be output
326  * @return 1 if a packet was output, 0 if no packet could be output,
327  * < 0 if an error occurred
328  */
330  AVPacket *pkt, int flush);
331 
333 
334 /**
335  * Return the frame duration in seconds. Return 0 if not available.
336  */
337 void ff_compute_frame_duration(AVFormatContext *s, int *pnum, int *pden, AVStream *st,
338  AVCodecParserContext *pc, AVPacket *pkt);
339 
340 unsigned int ff_codec_get_tag(const AVCodecTag *tags, enum AVCodecID id);
341 
342 enum AVCodecID ff_codec_get_id(const AVCodecTag *tags, unsigned int tag);
343 
344 /**
345  * Select a PCM codec based on the given parameters.
346  *
347  * @param bps bits-per-sample
348  * @param flt floating-point
349  * @param be big-endian
350  * @param sflags signed flags. each bit corresponds to one byte of bit depth.
351  * e.g. the 1st bit indicates if 8-bit should be signed or
352  * unsigned, the 2nd bit indicates if 16-bit should be signed or
353  * unsigned, etc... This is useful for formats such as WAVE where
354  * only 8-bit is unsigned and all other bit depths are signed.
355  * @return a PCM codec id or AV_CODEC_ID_NONE
356  */
357 enum AVCodecID ff_get_pcm_codec_id(int bps, int flt, int be, int sflags);
358 
359 /**
360  * Chooses a timebase for muxing the specified stream.
361  *
362  * The chosen timebase allows sample accurate timestamps based
363  * on the framerate or sample rate for audio streams. It also is
364  * at least as precise as 1/min_precision would be.
365  */
366 AVRational ff_choose_timebase(AVFormatContext *s, AVStream *st, int min_precision);
367 
368 /**
369  * Generate standard extradata for AVC-Intra based on width/height and field
370  * order.
371  */
373 
374 /**
375  * Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end
376  * which is always set to 0.
377  *
378  * @param size size of extradata
379  * @return 0 if OK, AVERROR_xxx on error
380  */
381 int ff_alloc_extradata(AVCodecContext *avctx, int size);
382 
383 /**
384  * Allocate extradata with additional FF_INPUT_BUFFER_PADDING_SIZE at end
385  * which is always set to 0 and fill it from pb.
386  *
387  * @param size size of extradata
388  * @return >= 0 if OK, AVERROR_xxx on error
389  */
390 int ff_get_extradata(AVCodecContext *avctx, AVIOContext *pb, int size);
391 
392 /**
393  * add frame for rfps calculation.
394  *
395  * @param dts timestamp of the i-th frame
396  * @return 0 if OK, AVERROR_xxx on error
397  */
398 int ff_rfps_add_frame(AVFormatContext *ic, AVStream *st, int64_t dts);
399 
401 
402 /**
403  * Flags for AVFormatContext.write_uncoded_frame()
404  */
406 
407  /**
408  * Query whether the feature is possible on this stream.
409  * The frame argument is ignored.
410  */
412 
413 };
414 
415 
416 #endif /* AVFORMAT_INTERNAL_H */