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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  /* initialize libavcodec, and register all codecs and formats */
96 
97  if (argc < 2) {
98  printf("usage: %s input_file\n"
99  "\n", argv[0]);
100  return 1;
101  }
102 
103  filename = argv[1];
104 
105  ret = avformat_open_input(&ic, filename, NULL, &format_opts);
106  av_dict_free(&format_opts);
107  if (ret < 0) {
108  fprintf(stderr, "cannot open %s\n", filename);
109  return 1;
110  }
111 
112  ret = avformat_find_stream_info(ic, NULL);
113  if (ret < 0) {
114  fprintf(stderr, "%s: could not find codec parameters\n", filename);
115  return 1;
116  }
117 
118  if(seekfirst != AV_NOPTS_VALUE){
119  if(firstback) avformat_seek_file(ic, -1, INT64_MIN, seekfirst, seekfirst, 0);
120  else avformat_seek_file(ic, -1, seekfirst, seekfirst, INT64_MAX, 0);
121  }
122  for(i=0; ; i++){
123  AVPacket pkt = { 0 };
124  AVStream *av_uninit(st);
125  char ts_buf[60];
126 
127  if(ret>=0){
128  for(j=0; j<frame_count; j++) {
129  ret= av_read_frame(ic, &pkt);
130  if(ret>=0){
131  char dts_buf[60];
132  st= ic->streams[pkt.stream_index];
133  ts_str(dts_buf, pkt.dts, st->time_base);
134  ts_str(ts_buf, pkt.pts, st->time_base);
135  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);
136  av_packet_unref(&pkt);
137  } else
138  printf("ret:%s", ret_str(ret)); // necessary to avoid trailing whitespace
139  printf("\n");
140  }
141  }
142 
143  if(i>25) break;
144 
145  stream_id= (i>>1)%(ic->nb_streams+1) - 1;
146  timestamp= (i*19362894167LL) % (duration*AV_TIME_BASE) - AV_TIME_BASE;
147  if(stream_id>=0){
148  st= ic->streams[stream_id];
149  timestamp= av_rescale_q(timestamp, AV_TIME_BASE_Q, st->time_base);
150  }
151  //FIXME fully test the new seek API
152  if(i&1) ret = avformat_seek_file(ic, stream_id, INT64_MIN, timestamp, timestamp, 0);
153  else ret = avformat_seek_file(ic, stream_id, timestamp, timestamp, INT64_MAX, 0);
154  ts_str(ts_buf, timestamp, stream_id < 0 ? AV_TIME_BASE_Q : st->time_base);
155  printf("ret:%-10s st:%2d flags:%d ts:%s\n", ret_str(ret), stream_id, i&1, ts_buf);
156  }
157 
159 
160  return 0;
161 }
#define NULL
Definition: coverity.c:32
int64_t pos
byte position in stream, -1 if unknown
Definition: avcodec.h:1600
int size
Definition: avcodec.h:1581
static AVPacket pkt
Format I/O context.
Definition: avformat.h:1325
static char buffer[20]
Definition: seek.c:32
AVStream ** streams
A list of all streams in the file.
Definition: avformat.h:1393
int64_t duration
Definition: movenc.c:63
AVFormatContext * avformat_alloc_context(void)
Allocate an AVFormatContext.
Definition: options.c:132
int flags
Flags modifying the (de)muxer behaviour.
Definition: avformat.h:1436
#define AVERROR_EOF
End of file.
Definition: error.h:55
AVDictionary * format_opts
Definition: cmdutils.c:69
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 AVERROR(e)
Definition: error.h:43
void av_dict_free(AVDictionary **pm)
Free all the memory allocated for an AVDictionary struct and all keys and values. ...
Definition: dict.c:202
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:1586
unsigned int nb_streams
Number of elements in AVFormatContext.streams.
Definition: avformat.h:1381
#define AV_TIME_BASE
Internal time base represented as integer.
Definition: avutil.h:246
#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:876
#define AV_TIME_BASE_Q
Internal time base represented as fractional value.
Definition: avutil.h:252
void av_packet_unref(AVPacket *pkt)
Wipe the packet.
Definition: avpacket.c:563
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:69
rational number numerator/denominator
Definition: rational.h:43
#define snprintf
Definition: snprintf.h:34
int av_read_frame(AVFormatContext *s, AVPacket *pkt)
Return the next frame of a stream.
Definition: utils.c:1640
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:2389
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:3277
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:4046
#define AVFMT_FLAG_FAST_SEEK
Enable fast, but inaccurate seeks for some formats.
Definition: avformat.h:1458
int avformat_open_input(AVFormatContext **ps, const char *url, AVInputFormat *fmt, AVDictionary **options)
Open an input stream and read the header.
Definition: utils.c:471
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:1579
#define av_uninit(x)
Definition: attributes.h:149
int stream_index
Definition: avcodec.h:1582
This structure stores compressed data.
Definition: avcodec.h:1557
void av_register_all(void)
Initialize libavformat and register all the muxers, demuxers and protocols.
Definition: allformats.c:44
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1573
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:240
GLuint buffer
Definition: opengl_enc.c:102