libavcodec/faac.c

   1 /*
   2  * Interface to libfaac for aac encoding
   3  * Copyright (c) 2002 Gildas Bazin <gbazin@netcourrier.com>
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19
  20 /**
  21  * @file faacaudio.c
  22  * Interface to libfaac for aac encoding.
  23  */
  24
  25 #include "avcodec.h"
  26 #include <faac.h>
  27
  28 typedef struct FaacAudioContext {
  29     faacEncHandle faac_handle;
  30 } FaacAudioContext;
  31
  32 static int Faac_encode_init(AVCodecContext *avctx)
  33 {
  34     FaacAudioContext *s = avctx->priv_data;
  35     faacEncConfigurationPtr faac_cfg;
  36     unsigned long samples_input, max_bytes_output;
  37
  38     /* number of channels */
  39     if (avctx->channels < 1 || avctx->channels > 6)
  40         return -1;
  41
  42     s->faac_handle = faacEncOpen(avctx->sample_rate,
  43                                  avctx->channels,
  44                                  &samples_input, &max_bytes_output);
  45
  46     /* check faac version */
  47     faac_cfg = faacEncGetCurrentConfiguration(s->faac_handle);
  48     if (faac_cfg->version != FAAC_CFG_VERSION) {
  49         av_log(avctx, AV_LOG_ERROR, "wrong libfaac version (compiled for: %d, using %d)\n", FAAC_CFG_VERSION, faac_cfg->version);
  50         faacEncClose(s->faac_handle);
  51         return -1;
  52     }
  53
  54     /* put the options in the configuration struct */
  55     faac_cfg->aacObjectType = LOW;
  56     faac_cfg->mpegVersion = MPEG4;
  57     faac_cfg->useTns = 0;
  58     faac_cfg->allowMidside = 1;
  59     faac_cfg->bitRate = avctx->bit_rate / avctx->channels;
  60     faac_cfg->bandWidth = avctx->cutoff;
  61     if(avctx->flags & CODEC_FLAG_QSCALE) {
  62         faac_cfg->bitRate = 0;
  63         faac_cfg->quantqual = avctx->global_quality / FF_QP2LAMBDA;
  64     }
  65     faac_cfg->outputFormat = 1;
  66     faac_cfg->inputFormat = FAAC_INPUT_16BIT;
  67
  68     avctx->frame_size = samples_input / avctx->channels;
  69
  70     avctx->coded_frame= avcodec_alloc_frame();
  71     avctx->coded_frame->key_frame= 1;
  72
  73     /* Set decoder specific info */
  74     avctx->extradata_size = 0;
  75     if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER) {
  76
  77         unsigned char *buffer;
  78         unsigned long decoder_specific_info_size;
  79
  80         if (!faacEncGetDecoderSpecificInfo(s->faac_handle, &buffer,
  81                                            &decoder_specific_info_size)) {
  82             avctx->extradata = buffer;
  83             avctx->extradata_size = decoder_specific_info_size;
  84             faac_cfg->outputFormat = 0;
  85         }
  86     }
  87
  88     if (!faacEncSetConfiguration(s->faac_handle, faac_cfg)) {
  89         av_log(avctx, AV_LOG_ERROR, "libfaac doesn't support this output format!\n");
  90         return -1;
  91     }
  92
  93     return 0;
  94 }
  95
  96 int Faac_encode_frame(AVCodecContext *avctx,
  97                       unsigned char *frame, int buf_size, void *data)
  98 {
  99     FaacAudioContext *s = avctx->priv_data;
 100     int bytes_written;
 101
 102     bytes_written = faacEncEncode(s->faac_handle,
 103                                   data,
 104                                   avctx->frame_size * avctx->channels,
 105                                   frame,
 106                                   buf_size);
 107
 108     return bytes_written;
 109 }
 110
 111 int Faac_encode_close(AVCodecContext *avctx)
 112 {
 113     FaacAudioContext *s = avctx->priv_data;
 114
 115     av_freep(&avctx->coded_frame);
 116
 117     //if (avctx->extradata_size) free(avctx->extradata);
 118
 119     faacEncClose(s->faac_handle);
 120     return 0;
 121 }
 122
 123 AVCodec faac_encoder = {
 124     "aac",
 125     CODEC_TYPE_AUDIO,
 126     CODEC_ID_AAC,
 127     sizeof(FaacAudioContext),
 128     Faac_encode_init,
 129     Faac_encode_frame,
 130     Faac_encode_close
 131 };