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 #define MAX_STD_TIMEBASES (30*12+30+3+6)
30 typedef struct FFStreamInfo {
31 int64_t last_dts;
32 int64_t duration_gcd;
33 int duration_count;
34 int64_t rfps_duration_sum;
35 double (*duration_error)[2][MAX_STD_TIMEBASES];
36 int64_t codec_info_duration;
37 int64_t codec_info_duration_fields;
38 int frame_delay_evidence;
39
40 /**
41 * 0 -> decoder has not been searched for yet.
42 * >0 -> decoder found
43 * <0 -> decoder with codec_id == -found_decoder has not been found
44 */
45 int found_decoder;
46
47 int64_t last_duration;
48
49 /**
50 * Those are used for average framerate estimation.
51 */
52 int64_t fps_first_dts;
53 int fps_first_dts_idx;
54 int64_t fps_last_dts;
55 int fps_last_dts_idx;
56 } FFStreamInfo;
57
58 /**
59 * Returned by demuxers to indicate that data was consumed but discarded
60 * (ignored streams or junk data). The framework will re-call the demuxer.
61 */
62 #define FFERROR_REDO FFERRTAG('R','E','D','O')
63
64 #define RELATIVE_TS_BASE (INT64_MAX - (1LL << 48))
65
is_relative(int64_t ts)66 static av_always_inline int is_relative(int64_t ts)
67 {
68 return ts > (RELATIVE_TS_BASE - (1LL << 48));
69 }
70
71 /**
72 * Wrap a given time stamp, if there is an indication for an overflow
73 *
74 * @param st stream
75 * @param timestamp the time stamp to wrap
76 * @return resulting time stamp
77 */
78 int64_t ff_wrap_timestamp(const AVStream *st, int64_t timestamp);
79
80 /**
81 * Read a transport packet from a media file.
82 *
83 * @param s media file handle
84 * @param pkt is filled
85 * @return 0 if OK, AVERROR_xxx on error
86 */
87 int ff_read_packet(AVFormatContext *s, AVPacket *pkt);
88
89 void ff_read_frame_flush(AVFormatContext *s);
90
91 /**
92 * Perform a binary search using av_index_search_timestamp() and
93 * AVInputFormat.read_timestamp().
94 *
95 * @param target_ts target timestamp in the time base of the given stream
96 * @param stream_index stream number
97 */
98 int ff_seek_frame_binary(AVFormatContext *s, int stream_index,
99 int64_t target_ts, int flags);
100
101 /**
102 * Update cur_dts of all streams based on the given timestamp and AVStream.
103 *
104 * Stream ref_st unchanged, others set cur_dts in their native time base.
105 * Only needed for timestamp wrapping or if (dts not set and pts!=dts).
106 * @param timestamp new dts expressed in time_base of param ref_st
107 * @param ref_st reference stream giving time_base of param timestamp
108 */
109 void avpriv_update_cur_dts(AVFormatContext *s, AVStream *ref_st, int64_t timestamp);
110
111 int ff_find_last_ts(AVFormatContext *s, int stream_index, int64_t *ts, int64_t *pos,
112 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
113
114 /**
115 * Perform a binary search using read_timestamp().
116 *
117 * @param target_ts target timestamp in the time base of the given stream
118 * @param stream_index stream number
119 */
120 int64_t ff_gen_search(AVFormatContext *s, int stream_index,
121 int64_t target_ts, int64_t pos_min,
122 int64_t pos_max, int64_t pos_limit,
123 int64_t ts_min, int64_t ts_max,
124 int flags, int64_t *ts_ret,
125 int64_t (*read_timestamp)(struct AVFormatContext *, int , int64_t *, int64_t ));
126
127 /**
128 * Internal version of av_index_search_timestamp
129 */
130 int ff_index_search_timestamp(const AVIndexEntry *entries, int nb_entries,
131 int64_t wanted_timestamp, int flags);
132
133 /**
134 * Internal version of av_add_index_entry
135 */
136 int ff_add_index_entry(AVIndexEntry **index_entries,
137 int *nb_index_entries,
138 unsigned int *index_entries_allocated_size,
139 int64_t pos, int64_t timestamp, int size, int distance, int flags);
140
141 void ff_configure_buffers_for_index(AVFormatContext *s, int64_t time_tolerance);
142
143 /**
144 * Ensure the index uses less memory than the maximum specified in
145 * AVFormatContext.max_index_size by discarding entries if it grows
146 * too large.
147 */
148 void ff_reduce_index(AVFormatContext *s, int stream_index);
149
150 /**
151 * add frame for rfps calculation.
152 *
153 * @param dts timestamp of the i-th frame
154 * @return 0 if OK, AVERROR_xxx on error
155 */
156 int ff_rfps_add_frame(AVFormatContext *ic, AVStream *st, int64_t dts);
157
158 void ff_rfps_calculate(AVFormatContext *ic);
159
160 /**
161 * Rescales a timestamp and the endpoints of an interval to which the temstamp
162 * belongs, from a timebase `tb_in` to a timebase `tb_out`.
163 *
164 * The upper (lower) bound of the output interval is rounded up (down) such that
165 * the output interval always falls within the intput interval. The timestamp is
166 * rounded to the nearest integer and halfway cases away from zero, and can
167 * therefore fall outside of the output interval.
168 *
169 * Useful to simplify the rescaling of the arguments of AVInputFormat::read_seek2()
170 *
171 * @param[in] tb_in Timebase of the input `min_ts`, `ts` and `max_ts`
172 * @param[in] tb_out Timebase of the ouput `min_ts`, `ts` and `max_ts`
173 * @param[in,out] min_ts Lower bound of the interval
174 * @param[in,out] ts Timestamp
175 * @param[in,out] max_ts Upper bound of the interval
176 */
177 void ff_rescale_interval(AVRational tb_in, AVRational tb_out,
178 int64_t *min_ts, int64_t *ts, int64_t *max_ts);
179
180 void avpriv_stream_set_need_parsing(AVStream *st, enum AVStreamParseType type);
181
182 /**
183 * Add a new chapter.
184 *
185 * @param s media file handle
186 * @param id unique ID for this chapter
187 * @param start chapter start time in time_base units
188 * @param end chapter end time in time_base units
189 * @param title chapter title
190 *
191 * @return AVChapter or NULL on error
192 */
193 AVChapter *avpriv_new_chapter(AVFormatContext *s, int64_t id, AVRational time_base,
194 int64_t start, int64_t end, const char *title);
195
196 /**
197 * Add an attached pic to an AVStream.
198 *
199 * @param st if set, the stream to add the attached pic to;
200 * if unset, a new stream will be added to s.
201 * @param pb AVIOContext to read data from if buf is unset.
202 * @param buf if set, it contains the data and size information to be used
203 * for the attached pic; if unset, data is read from pb.
204 * @param size the size of the data to read if buf is unset.
205 *
206 * @return 0 on success, < 0 on error. On error, this function removes
207 * the stream it has added (if any).
208 */
209 int ff_add_attached_pic(AVFormatContext *s, AVStream *st, AVIOContext *pb,
210 AVBufferRef **buf, int size);
211
212 /**
213 * Add side data to a packet for changing parameters to the given values.
214 * Parameters set to 0 aren't included in the change.
215 */
216 int ff_add_param_change(AVPacket *pkt, int32_t channels,
217 uint64_t channel_layout, int32_t sample_rate,
218 int32_t width, int32_t height);
219
220 /**
221 * Generate standard extradata for AVC-Intra based on width/height and field
222 * order.
223 */
224 int ff_generate_avci_extradata(AVStream *st);
225
226 /**
227 * Allocate extradata with additional AV_INPUT_BUFFER_PADDING_SIZE at end
228 * which is always set to 0 and fill it from pb.
229 *
230 * @param size size of extradata
231 * @return >= 0 if OK, AVERROR_xxx on error
232 */
233 int ff_get_extradata(void *logctx, AVCodecParameters *par, AVIOContext *pb, int size);
234
235 /**
236 * Find stream index based on format-specific stream ID
237 * @return stream index, or < 0 on error
238 */
239 int ff_find_stream_index(const AVFormatContext *s, int id);
240
241 #endif /* AVFORMAT_DEMUX_H */
242