rsodec.c 2.9 KB

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  1. /*
  2. * RSO demuxer
  3. * Copyright (c) 2001 Fabrice Bellard (original AU code)
  4. * Copyright (c) 2010 Rafael Carre
  5. *
  6. * This file is part of FFmpeg.
  7. *
  8. * FFmpeg is free software; you can redistribute it and/or
  9. * modify it under the terms of the GNU Lesser General Public
  10. * License as published by the Free Software Foundation; either
  11. * version 2.1 of the License, or (at your option) any later version.
  12. *
  13. * FFmpeg is distributed in the hope that it will be useful,
  14. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16. * Lesser General Public License for more details.
  17. *
  18. * You should have received a copy of the GNU Lesser General Public
  19. * License along with FFmpeg; if not, write to the Free Software
  20. * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21. */
  22. #include "libavutil/intreadwrite.h"
  23. #include "avformat.h"
  24. #include "internal.h"
  25. #include "pcm.h"
  26. #include "riff.h"
  27. #include "rso.h"
  28. static int rso_read_header(AVFormatContext *s, AVFormatParameters *ap)
  29. {
  30. AVIOContext *pb = s->pb;
  31. int id, rate, bps;
  32. unsigned int size;
  33. enum CodecID codec;
  34. AVStream *st;
  35. id = avio_rb16(pb);
  36. size = avio_rb16(pb);
  37. rate = avio_rb16(pb);
  38. avio_rb16(pb); /* play mode ? (0x0000 = don't loop) */
  39. codec = ff_codec_get_id(ff_codec_rso_tags, id);
  40. if (codec == CODEC_ID_ADPCM_IMA_WAV) {
  41. av_log(s, AV_LOG_ERROR, "ADPCM in RSO not implemented\n");
  42. return AVERROR_PATCHWELCOME;
  43. }
  44. bps = av_get_bits_per_sample(codec);
  45. if (!bps) {
  46. av_log_ask_for_sample(s, "could not determine bits per sample\n");
  47. return AVERROR_INVALIDDATA;
  48. }
  49. /* now we are ready: build format streams */
  50. st = avformat_new_stream(s, NULL);
  51. if (!st)
  52. return AVERROR(ENOMEM);
  53. st->duration = (size * 8) / bps;
  54. st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
  55. st->codec->codec_tag = id;
  56. st->codec->codec_id = codec;
  57. st->codec->channels = 1;
  58. st->codec->sample_rate = rate;
  59. avpriv_set_pts_info(st, 64, 1, rate);
  60. return 0;
  61. }
  62. #define BLOCK_SIZE 1024 /* in samples */
  63. static int rso_read_packet(AVFormatContext *s, AVPacket *pkt)
  64. {
  65. int bps = av_get_bits_per_sample(s->streams[0]->codec->codec_id);
  66. int ret = av_get_packet(s->pb, pkt, BLOCK_SIZE * bps >> 3);
  67. if (ret < 0)
  68. return ret;
  69. pkt->stream_index = 0;
  70. /* note: we need to modify the packet size here to handle the last packet */
  71. pkt->size = ret;
  72. return 0;
  73. }
  74. AVInputFormat ff_rso_demuxer = {
  75. .name = "rso",
  76. .long_name = NULL_IF_CONFIG_SMALL("Lego Mindstorms RSO format"),
  77. .extensions = "rso",
  78. .read_header = rso_read_header,
  79. .read_packet = rso_read_packet,
  80. .read_seek = pcm_read_seek,
  81. .codec_tag = (const AVCodecTag* const []){ff_codec_rso_tags, 0},
  82. };