FFmpeg coverage


Directory: ../../../ffmpeg/
File: src/libavformat/demux.h
Date: 2025-10-10 03:51:19
Exec Total Coverage
Lines: 2 2 100.0%
Functions: 1 1 100.0%
Branches: 0 0 -%

Line Branch Exec Source
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_DEMUX_H
22 #define AVFORMAT_DEMUX_H
23
24 #include <stdint.h>
25 #include "libavutil/rational.h"
26 #include "libavcodec/packet.h"
27 #include "avformat.h"
28
29 struct AVDeviceInfoList;
30
31 /**
32 * For an FFInputFormat with this flag set read_close() needs to be called
33 * by the caller upon read_header() failure.
34 */
35 #define FF_INFMT_FLAG_INIT_CLEANUP (1 << 0)
36
37 /*
38 * Prefer the codec framerate for avg_frame_rate computation.
39 */
40 #define FF_INFMT_FLAG_PREFER_CODEC_FRAMERATE (1 << 1)
41
42 /**
43 * Automatically parse ID3v2 metadata
44 */
45 #define FF_INFMT_FLAG_ID3V2_AUTO (1 << 2)
46
47 typedef struct FFInputFormat {
48 /**
49 * The public AVInputFormat. See avformat.h for it.
50 */
51 AVInputFormat p;
52
53 /**
54 * Raw demuxers store their codec ID here.
55 */
56 enum AVCodecID raw_codec_id;
57
58 /**
59 * Size of private data so that it can be allocated in the wrapper.
60 */
61 int priv_data_size;
62
63 /**
64 * Internal flags. See FF_INFMT_FLAG_* above and FF_FMT_FLAG_* in internal.h.
65 */
66 int flags_internal;
67
68 /**
69 * Tell if a given file has a chance of being parsed as this format.
70 * The buffer provided is guaranteed to be AVPROBE_PADDING_SIZE bytes
71 * big so you do not have to check for that unless you need more.
72 */
73 int (*read_probe)(const AVProbeData *);
74
75 /**
76 * Read the format header and initialize the AVFormatContext
77 * structure. Return 0 if OK. 'avformat_new_stream' should be
78 * called to create new streams.
79 */
80 int (*read_header)(struct AVFormatContext *);
81
82 /**
83 * Read one packet and put it in 'pkt'. pts and flags are also
84 * set. 'avformat_new_stream' can be called only if the flag
85 * AVFMTCTX_NOHEADER is used and only in the calling thread (not in a
86 * background thread).
87 * @return 0 on success, < 0 on error.
88 * Upon returning an error, pkt must be unreferenced by the caller.
89 */
90 int (*read_packet)(struct AVFormatContext *, AVPacket *pkt);
91
92 /**
93 * Close the stream. The AVFormatContext and AVStreams are not
94 * freed by this function
95 */
96 int (*read_close)(struct AVFormatContext *);
97
98 /**
99 * Seek to a given timestamp relative to the frames in
100 * stream component stream_index.
101 * @param stream_index Must not be -1.
102 * @param flags Selects which direction should be preferred if no exact
103 * match is available.
104 * @return >= 0 on success (but not necessarily the new offset)
105 */
106 int (*read_seek)(struct AVFormatContext *,
107 int stream_index, int64_t timestamp, int flags);
108
109 /**
110 * Get the next timestamp in stream[stream_index].time_base units.
111 * @return the timestamp or AV_NOPTS_VALUE if an error occurred
112 */
113 int64_t (*read_timestamp)(struct AVFormatContext *s, int stream_index,
114 int64_t *pos, int64_t pos_limit);
115
116 /**
117 * Start/resume playing - only meaningful if using a network-based format
118 * (RTSP).
119 */
120 int (*read_play)(struct AVFormatContext *);
121
122 /**
123 * Pause playing - only meaningful if using a network-based format
124 * (RTSP).
125 */
126 int (*read_pause)(struct AVFormatContext *);
127
128 /**
129 * Seek to timestamp ts.
130 * Seeking will be done so that the point from which all active streams
131 * can be presented successfully will be closest to ts and within min/max_ts.
132 * Active streams are all streams that have AVStream.discard < AVDISCARD_ALL.
133 */
134 int (*read_seek2)(struct AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags);
135
136 /**
137 * Returns device list with it properties.
138 * @see avdevice_list_devices() for more details.
139 */
140 int (*get_device_list)(struct AVFormatContext *s, struct AVDeviceInfoList *device_list);
141 } FFInputFormat;
142
143 6147968 static inline const FFInputFormat *ffifmt(const AVInputFormat *fmt)
144 {
145 6147968 return (const FFInputFormat*)fmt;
146 }
147
148 #define MAX_STD_TIMEBASES (30*12+30+3+6)
149 typedef struct FFStreamInfo {
150 int64_t last_dts;
151 int64_t duration_gcd;
152 int duration_count;
153 int64_t rfps_duration_sum;
154 double (*duration_error)[2][MAX_STD_TIMEBASES];
155 int64_t codec_info_duration;
156 int64_t codec_info_duration_fields;
157 int frame_delay_evidence;
158
159 /**
160 * 0 -> decoder has not been searched for yet.
161 * >0 -> decoder found
162 * <0 -> decoder with codec_id == -found_decoder has not been found
163 */
164 int found_decoder;
165
166 int64_t last_duration;
167
168 /**
169 * Those are used for average framerate estimation.
170 */
171 int64_t fps_first_dts;
172 int fps_first_dts_idx;
173 int64_t fps_last_dts;
174 int fps_last_dts_idx;
175 } FFStreamInfo;
176
177 /**
178 * Returned by demuxers to indicate that data was consumed but discarded
179 * (ignored streams or junk data). The framework will re-call the demuxer.
180 */
181 #define FFERROR_REDO FFERRTAG('R','E','D','O')
182
183 /**
184 * Read a transport packet from a media file.
185 *
186 * @param s media file handle
187 * @param pkt is filled
188 * @return 0 if OK, AVERROR_xxx on error
189 */
190 int ff_read_packet(AVFormatContext *s, AVPacket *pkt);
191
192 void ff_read_frame_flush(AVFormatContext *s);
193
194 /**
195 * Perform a binary search using av_index_search_timestamp() and
196 * FFInputFormat.read_timestamp().
197 *
198 * @param target_ts target timestamp in the time base of the given stream
199 * @param stream_index stream number
200 */
201 int ff_seek_frame_binary(AVFormatContext *s, int stream_index,
202 int64_t target_ts, int flags);
203
204 /**
205 * Update cur_dts of all streams based on the given timestamp and AVStream.
206 *
207 * Stream ref_st unchanged, others set cur_dts in their native time base.
208 * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
209 * @param timestamp new dts expressed in time_base of param ref_st
210 * @param ref_st reference stream giving time_base of param timestamp
211 */
212 void avpriv_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
213
214 int ff_find_last_ts(AVFormatContext *s, int stream_index, int64_t *ts, int64_t *pos,
215 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
216
217 /**
218 * Perform a binary search using read_timestamp().
219 *
220 * @param target_ts target timestamp in the time base of the given stream
221 * @param stream_index stream number
222 */
223 int64_t ff_gen_search(AVFormatContext *s, int stream_index,
224 int64_t target_ts, int64_t pos_min,
225 int64_t pos_max, int64_t pos_limit,
226 int64_t ts_min, int64_t ts_max,
227 int flags, int64_t *ts_ret,
228 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
229
230 /**
231 * Internal version of av_index_search_timestamp
232 */
233 int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
234 int64_t wanted_timestamp, int flags);
235
236 /**
237 * Internal version of av_add_index_entry
238 */
239 int ff_add_index_entry(AVIndexEntry **index_entries,
240 int *nb_index_entries,
241 unsigned int *index_entries_allocated_size,
242 int64_t pos, int64_t timestamp, int size, int distance, int flags);
243
244 void ff_configure_buffers_for_index(AVFormatContext *s, int64_t time_tolerance);
245
246 /**
247 * Ensure the index uses less memory than the maximum specified in
248 * AVFormatContext.max_index_size by discarding entries if it grows
249 * too large.
250 */
251 void ff_reduce_index(AVFormatContext *s, int stream_index);
252
253 /**
254 * add frame for rfps calculation.
255 *
256 * @param dts timestamp of the i-th frame
257 * @return 0 if OK, AVERROR_xxx on error
258 */
259 int ff_rfps_add_frame(AVFormatContext *ic, AVStream *st, int64_t dts);
260
261 void ff_rfps_calculate(AVFormatContext *ic);
262
263 /**
264 * Rescales a timestamp and the endpoints of an interval to which the temstamp
265 * belongs, from a timebase `tb_in` to a timebase `tb_out`.
266 *
267 * The upper (lower) bound of the output interval is rounded up (down) such that
268 * the output interval always falls within the input interval. The timestamp is
269 * rounded to the nearest integer and halfway cases away from zero, and can
270 * therefore fall outside of the output interval.
271 *
272 * Useful to simplify the rescaling of the arguments of FFInputFormat::read_seek2()
273 *
274 * @param[in] tb_in Timebase of the input `min_ts`, `ts` and `max_ts`
275 * @param[in] tb_out Timebase of the output `min_ts`, `ts` and `max_ts`
276 * @param[in,out] min_ts Lower bound of the interval
277 * @param[in,out] ts Timestamp
278 * @param[in,out] max_ts Upper bound of the interval
279 */
280 void ff_rescale_interval(AVRational tb_in, AVRational tb_out,
281 int64_t *min_ts, int64_t *ts, int64_t *max_ts);
282
283 void avpriv_stream_set_need_parsing(AVStream *st, enum AVStreamParseType type);
284
285 /**
286 * Add a new chapter.
287 *
288 * @param s media file handle
289 * @param id unique ID for this chapter
290 * @param start chapter start time in time_base units
291 * @param end chapter end time in time_base units
292 * @param title chapter title
293 *
294 * @return AVChapter or NULL on error
295 */
296 AVChapter *avpriv_new_chapter(AVFormatContext *s, int64_t id, AVRational time_base,
297 int64_t start, int64_t end, const char *title);
298
299 /**
300 * Add an attached pic to an AVStream.
301 *
302 * @param st if set, the stream to add the attached pic to;
303 * if unset, a new stream will be added to s.
304 * @param pb AVIOContext to read data from if buf is unset.
305 * @param buf if set, it contains the data and size information to be used
306 * for the attached pic; if unset, data is read from pb.
307 * @param size the size of the data to read if buf is unset.
308 *
309 * @return 0 on success, < 0 on error. On error, this function removes
310 * the stream it has added (if any).
311 */
312 int ff_add_attached_pic(AVFormatContext *s, AVStream *st, AVIOContext *pb,
313 AVBufferRef **buf, int size);
314
315 /**
316 * Add side data to a packet for changing parameters to the given values.
317 * Parameters set to 0 aren't included in the change.
318 */
319 int ff_add_param_change(AVPacket *pkt, int32_t channels,
320 uint64_t channel_layout, int32_t sample_rate,
321 int32_t width, int32_t height);
322
323 /**
324 * Generate standard extradata for AVC-Intra based on width/height and field
325 * order.
326 */
327 int ff_generate_avci_extradata(AVStream *st);
328
329 /**
330 * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
331 * which is always set to 0 and fill it from pb.
332 *
333 * @param size size of extradata
334 * @return >= 0 if OK, AVERROR_xxx on error
335 */
336 int ff_get_extradata(void *logctx, AVCodecParameters *par, AVIOContext *pb, int size);
337
338 /**
339 * Find stream index based on format-specific stream ID
340 * @return stream index, or < 0 on error
341 */
342 int ff_find_stream_index(const AVFormatContext *s, int id);
343
344 int ff_buffer_packet(AVFormatContext *s, AVPacket *pkt);
345
346 #endif /* AVFORMAT_DEMUX_H */
347