Subversion Repositories Kolibri OS

Rev

Blame | Last modification | View Log | RSS feed

  1. /*
  2.  * Packed Animation File audio decoder
  3.  * Copyright (c) 2012 Paul B Mahol
  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 "libavutil/intreadwrite.h"
  23.  
  24. #include "avcodec.h"
  25. #include "internal.h"
  26. #include "mathops.h"
  27. #include "paf.h"
  28.  
  29. static av_cold int paf_audio_init(AVCodecContext *avctx)
  30. {
  31.     if (avctx->channels != 2) {
  32.         av_log(avctx, AV_LOG_ERROR, "invalid number of channels\n");
  33.         return AVERROR_INVALIDDATA;
  34.     }
  35.  
  36.     avctx->channel_layout = AV_CH_LAYOUT_STEREO;
  37.     avctx->sample_fmt     = AV_SAMPLE_FMT_S16;
  38.  
  39.     return 0;
  40. }
  41.  
  42. static int paf_audio_decode(AVCodecContext *avctx, void *data,
  43.                             int *got_frame, AVPacket *pkt)
  44. {
  45.     AVFrame *frame = data;
  46.     int16_t *output_samples;
  47.     const uint8_t *src = pkt->data;
  48.     int frames, ret, i, j;
  49.     int16_t cb[256];
  50.  
  51.     frames = pkt->size / PAF_SOUND_FRAME_SIZE;
  52.     if (frames < 1)
  53.         return AVERROR_INVALIDDATA;
  54.  
  55.     frame->nb_samples = PAF_SOUND_SAMPLES * frames;
  56.     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
  57.         return ret;
  58.  
  59.     output_samples = (int16_t *)frame->data[0];
  60.     // codebook of 256 16-bit samples and 8-bit indices to it
  61.     for (j = 0; j < frames; j++) {
  62.         for (i = 0; i < 256; i++)
  63.             cb[i] = sign_extend(AV_RL16(src + i * 2), 16);
  64.         src += 256 * 2;
  65.         // always 2 channels
  66.         for (i = 0; i < PAF_SOUND_SAMPLES * 2; i++)
  67.             *output_samples++ = cb[*src++];
  68.     }
  69.     *got_frame = 1;
  70.  
  71.     return pkt->size;
  72. }
  73.  
  74. AVCodec ff_paf_audio_decoder = {
  75.     .name         = "paf_audio",
  76.     .long_name    = NULL_IF_CONFIG_SMALL("Amazing Studio Packed Animation File Audio"),
  77.     .type         = AVMEDIA_TYPE_AUDIO,
  78.     .id           = AV_CODEC_ID_PAF_AUDIO,
  79.     .init         = paf_audio_init,
  80.     .decode       = paf_audio_decode,
  81.     .capabilities = AV_CODEC_CAP_DR1,
  82. };
  83.