seek_test.c 2.9 KB

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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. #include <stdint.h>
  22. #include <stdlib.h>
  23. #include <stdio.h>
  24. #include "libavformat/avformat.h"
  25. #undef exit
  26. int main(int argc, char **argv)
  27. {
  28. const char *filename;
  29. AVFormatContext *ic;
  30. int i, ret, stream_id;
  31. int64_t timestamp;
  32. AVFormatParameters params, *ap= &params;
  33. memset(ap, 0, sizeof(params));
  34. ap->channels=1;
  35. ap->sample_rate= 22050;
  36. /* initialize libavcodec, and register all codecs and formats */
  37. av_register_all();
  38. if (argc != 2) {
  39. printf("usage: %s input_file\n"
  40. "\n", argv[0]);
  41. exit(1);
  42. }
  43. filename = argv[1];
  44. /* allocate the media context */
  45. ic = avformat_alloc_context();
  46. if (!ic) {
  47. fprintf(stderr, "Memory error\n");
  48. exit(1);
  49. }
  50. ret = av_open_input_file(&ic, filename, NULL, 0, ap);
  51. if (ret < 0) {
  52. fprintf(stderr, "cannot open %s\n", filename);
  53. exit(1);
  54. }
  55. ret = av_find_stream_info(ic);
  56. if (ret < 0) {
  57. fprintf(stderr, "%s: could not find codec parameters\n", filename);
  58. exit(1);
  59. }
  60. for(i=0; ; i++){
  61. AVPacket pkt;
  62. AVStream *st;
  63. memset(&pkt, 0, sizeof(pkt));
  64. if(ret>=0){
  65. ret= av_read_frame(ic, &pkt);
  66. printf("ret:%2d", ret);
  67. if(ret>=0){
  68. st= ic->streams[pkt.stream_index];
  69. printf(" st:%2d dts:%f pts:%f pos:%" PRId64 " size:%d flags:%d", pkt.stream_index, pkt.dts*av_q2d(st->time_base), pkt.pts*av_q2d(st->time_base), pkt.pos, pkt.size, pkt.flags);
  70. }
  71. printf("\n");
  72. }
  73. if(i>25) break;
  74. stream_id= (i>>1)%(ic->nb_streams+1) - 1;
  75. timestamp= (i*19362894167LL) % (4*AV_TIME_BASE) - AV_TIME_BASE;
  76. if(stream_id>=0){
  77. st= ic->streams[stream_id];
  78. timestamp= av_rescale_q(timestamp, AV_TIME_BASE_Q, st->time_base);
  79. }
  80. ret = av_seek_frame(ic, stream_id, timestamp, (i&1)*AVSEEK_FLAG_BACKWARD);
  81. printf("ret:%2d st:%2d ts:%f flags:%d\n", ret, stream_id, timestamp*(stream_id<0 ? 1.0/AV_TIME_BASE : av_q2d(st->time_base)), i&1);
  82. }
  83. return 0;
  84. }