FFmpeg
seek.c
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1 /*
2  * Copyright (c) 2003 Fabrice Bellard
3  * Copyright (c) 2007 Michael Niedermayer
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include <stdint.h>
23 #include <stdlib.h>
24 #include <stdio.h>
25 #include <string.h>
26 
27 #include "libavutil/common.h"
28 #include "libavutil/mathematics.h"
29 
30 #include "libavformat/avformat.h"
31 
32 static char buffer[20];
33 
34 static const char *ret_str(int v)
35 {
36  switch (v) {
37  case AVERROR_EOF: return "-EOF";
38  case AVERROR(EIO): return "-EIO";
39  case AVERROR(ENOMEM): return "-ENOMEM";
40  case AVERROR(EINVAL): return "-EINVAL";
41  default:
42  snprintf(buffer, sizeof(buffer), "%2d", v);
43  return buffer;
44  }
45 }
46 
47 static void ts_str(char buffer[60], int64_t ts, AVRational base)
48 {
49  if (ts == AV_NOPTS_VALUE) {
50  strcpy(buffer, " NOPTS ");
51  return;
52  }
53  ts= av_rescale_q(ts, base, (AVRational){1, 1000000});
54  snprintf(buffer, 60, "%c%"PRId64".%06"PRId64"", ts<0 ? '-' : ' ', FFABS(ts)/1000000, FFABS(ts)%1000000);
55 }
56 
57 int main(int argc, char **argv)
58 {
59  const char *filename;
61  int i, ret, stream_id;
62  int j;
63  int64_t timestamp;
65  int64_t seekfirst = AV_NOPTS_VALUE;
66  int firstback=0;
67  int frame_count = 1;
68  int duration = 4;
69 
70  for(i=2; i<argc; i+=2){
71  if (!strcmp(argv[i], "-seekforw")){
72  seekfirst = atoi(argv[i+1]);
73  } else if(!strcmp(argv[i], "-seekback")){
74  seekfirst = atoi(argv[i+1]);
75  firstback = 1;
76  } else if(!strcmp(argv[i], "-frames")){
77  frame_count = atoi(argv[i+1]);
78  } else if(!strcmp(argv[i], "-duration")){
79  duration = atoi(argv[i+1]);
80  } else if(!strcmp(argv[i], "-fastseek")) {
81  if (atoi(argv[i+1])) {
83  }
84  } else if(argv[i][0] == '-' && argv[i+1]) {
85  av_dict_set(&format_opts, argv[i] + 1, argv[i+1], 0);
86  } else {
87  argc = 1;
88  }
89  }
90 
91  av_dict_set(&format_opts, "channels", "1", 0);
92  av_dict_set(&format_opts, "sample_rate", "22050", 0);
93 
94  if (argc < 2) {
95  printf("usage: %s input_file\n"
96  "\n", argv[0]);
97  return 1;
98  }
99 
100  filename = argv[1];
101 
102  ret = avformat_open_input(&ic, filename, NULL, &format_opts);
103  av_dict_free(&format_opts);
104  if (ret < 0) {
105  fprintf(stderr, "cannot open %s\n", filename);
106  return 1;
107  }
108 
109  ret = avformat_find_stream_info(ic, NULL);
110  if (ret < 0) {
111  fprintf(stderr, "%s: could not find codec parameters\n", filename);
112  return 1;
113  }
114 
115  if(seekfirst != AV_NOPTS_VALUE){
116  if(firstback) avformat_seek_file(ic, -1, INT64_MIN, seekfirst, seekfirst, 0);
117  else avformat_seek_file(ic, -1, seekfirst, seekfirst, INT64_MAX, 0);
118  }
119  for(i=0; ; i++){
120  AVPacket pkt = { 0 };
121  AVStream *av_uninit(st);
122  char ts_buf[60];
123 
124  if(ret>=0){
125  for(j=0; j<frame_count; j++) {
126  ret= av_read_frame(ic, &pkt);
127  if(ret>=0){
128  char dts_buf[60];
129  st= ic->streams[pkt.stream_index];
130  ts_str(dts_buf, pkt.dts, st->time_base);
131  ts_str(ts_buf, pkt.pts, st->time_base);
132  printf("ret:%-10s st:%2d flags:%d dts:%s pts:%s pos:%7" PRId64 " size:%6d", ret_str(ret), pkt.stream_index, pkt.flags, dts_buf, ts_buf, pkt.pos, pkt.size);
133  av_packet_unref(&pkt);
134  } else
135  printf("ret:%s", ret_str(ret)); // necessary to avoid trailing whitespace
136  printf("\n");
137  }
138  }
139 
140  if(i>25) break;
141 
142  stream_id= (i>>1)%(ic->nb_streams+1) - 1;
143  timestamp= (i*19362894167LL) % (duration*AV_TIME_BASE) - AV_TIME_BASE;
144  if(stream_id>=0){
145  st= ic->streams[stream_id];
146  timestamp= av_rescale_q(timestamp, AV_TIME_BASE_Q, st->time_base);
147  }
148  //FIXME fully test the new seek API
149  if(i&1) ret = avformat_seek_file(ic, stream_id, INT64_MIN, timestamp, timestamp, 0);
150  else ret = avformat_seek_file(ic, stream_id, timestamp, timestamp, INT64_MAX, 0);
151  ts_str(ts_buf, timestamp, stream_id < 0 ? AV_TIME_BASE_Q : st->time_base);
152  printf("ret:%-10s st:%2d flags:%d ts:%s\n", ret_str(ret), stream_id, i&1, ts_buf);
153  }
154 
156 
157  return 0;
158 }
#define NULL
Definition: coverity.c:32
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1500
int size
Definition: avcodec.h:1481
int avformat_open_input(AVFormatContext **ps, const char *url, ff_const59 AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:539
static AVPacket pkt
uint8_t base
Definition: vp3data.h:202
Format I/O context.
Definition: avformat.h:1358
static char buffer[20]
Definition: seek.c:32
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1426
int64_t duration
Definition: movenc.c:63
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:144
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1489
#define AVERROR_EOF
End of file.
Definition: error.h:55
AVDictionary * format_opts
Definition: cmdutils.c:73
int64_t av_rescale_q(int64_t a, AVRational bq, AVRational cq)
Rescale a 64-bit integer by 2 rational numbers.
Definition: mathematics.c:142
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:203
static void ts_str(char buffer[60], int64_t ts, AVRational base)
Definition: seek.c:47
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1486
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1414
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:254
#define FFABS(a)
Absolute value, Note, INT_MIN / INT64_MIN result in undefined behavior as they are not representable ...
Definition: common.h:72
Stream structure.
Definition: avformat.h:881
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:260
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:599
int av_dict_set(AVDictionary **pm, const char *key, const char *value, int flags)
Set the given entry in *pm, overwriting an existing entry.
Definition: dict.c:70
Rational number (pair of numerator and denominator).
Definition: rational.h:58
#define snprintf
Definition: snprintf.h:34
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1777
int avformat_seek_file(AVFormatContext *s, int stream_index, int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
Seek to timestamp ts.
Definition: utils.c:2545
Main libavformat public API header.
common internal and external API header
int avformat_find_stream_info(AVFormatContext *ic, AVDictionary **options)
Read packets of a media file to get stream information.
Definition: utils.c:3600
static const char * ret_str(int v)
Definition: seek.c:34
void avformat_close_input(AVFormatContext **s)
Close an opened input AVFormatContext.
Definition: utils.c:4474
#define AVFMT_FLAG_FAST_SEEK
Enable fast, but inaccurate seeks for some formats.
Definition: avformat.h:1515
printf("static const uint8_t my_array[100] = {\n")
int main(int argc, char **argv)
Definition: seek.c:57
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1479
#define av_uninit(x)
Definition: attributes.h:148
int stream_index
Definition: avcodec.h:1482
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
This structure stores compressed data.
Definition: avcodec.h:1457
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1473
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
GLuint buffer
Definition: opengl_enc.c:101