sndio_dec.c 3.3 KB

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  1. /*
  2. * sndio play and grab interface
  3. * Copyright (c) 2010 Jacob Meuser
  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 <sndio.h>
  23. #include "libavformat/avformat.h"
  24. #include "libavformat/internal.h"
  25. #include "libavutil/opt.h"
  26. #include "libavutil/time.h"
  27. #include "sndio_common.h"
  28. static av_cold int audio_read_header(AVFormatContext *s1)
  29. {
  30. SndioData *s = s1->priv_data;
  31. AVStream *st;
  32. int ret;
  33. st = avformat_new_stream(s1, NULL);
  34. if (!st)
  35. return AVERROR(ENOMEM);
  36. ret = ff_sndio_open(s1, 0, s1->filename);
  37. if (ret < 0)
  38. return ret;
  39. /* take real parameters */
  40. st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
  41. st->codec->codec_id = s->codec_id;
  42. st->codec->sample_rate = s->sample_rate;
  43. st->codec->channels = s->channels;
  44. avpriv_set_pts_info(st, 64, 1, 1000000); /* 64 bits pts in us */
  45. return 0;
  46. }
  47. static int audio_read_packet(AVFormatContext *s1, AVPacket *pkt)
  48. {
  49. SndioData *s = s1->priv_data;
  50. int64_t bdelay, cur_time;
  51. int ret;
  52. if ((ret = av_new_packet(pkt, s->buffer_size)) < 0)
  53. return ret;
  54. ret = sio_read(s->hdl, pkt->data, pkt->size);
  55. if (ret == 0 || sio_eof(s->hdl)) {
  56. av_free_packet(pkt);
  57. return AVERROR_EOF;
  58. }
  59. pkt->size = ret;
  60. s->softpos += ret;
  61. /* compute pts of the start of the packet */
  62. cur_time = av_gettime();
  63. bdelay = ret + s->hwpos - s->softpos;
  64. /* convert to pts */
  65. pkt->pts = cur_time - ((bdelay * 1000000) /
  66. (s->bps * s->channels * s->sample_rate));
  67. return 0;
  68. }
  69. static av_cold int audio_read_close(AVFormatContext *s1)
  70. {
  71. SndioData *s = s1->priv_data;
  72. ff_sndio_close(s);
  73. return 0;
  74. }
  75. static const AVOption options[] = {
  76. { "sample_rate", "", offsetof(SndioData, sample_rate), AV_OPT_TYPE_INT, {.i64 = 48000}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
  77. { "channels", "", offsetof(SndioData, channels), AV_OPT_TYPE_INT, {.i64 = 2}, 1, INT_MAX, AV_OPT_FLAG_DECODING_PARAM },
  78. { NULL },
  79. };
  80. static const AVClass sndio_demuxer_class = {
  81. .class_name = "sndio indev",
  82. .item_name = av_default_item_name,
  83. .option = options,
  84. .version = LIBAVUTIL_VERSION_INT,
  85. .category = AV_CLASS_CATEGORY_DEVICE_AUDIO_INPUT,
  86. };
  87. AVInputFormat ff_sndio_demuxer = {
  88. .name = "sndio",
  89. .long_name = NULL_IF_CONFIG_SMALL("sndio audio capture"),
  90. .priv_data_size = sizeof(SndioData),
  91. .read_header = audio_read_header,
  92. .read_packet = audio_read_packet,
  93. .read_close = audio_read_close,
  94. .flags = AVFMT_NOFILE,
  95. .priv_class = &sndio_demuxer_class,
  96. };