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libfaac.c
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1 /*
2  * Interface to libfaac for aac encoding
3  * Copyright (c) 2002 Gildas Bazin <gbazin@netcourrier.com>
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 /**
23  * @file
24  * Interface to libfaac for aac encoding.
25  */
26 
27 #include <faac.h>
28 
30 #include "libavutil/common.h"
31 #include "avcodec.h"
32 #include "audio_frame_queue.h"
33 #include "internal.h"
34 
35 
36 /* libfaac has an encoder delay of 1024 samples */
37 #define FAAC_DELAY_SAMPLES 1024
38 
39 typedef struct FaacAudioContext {
40  faacEncHandle faac_handle;
43 
45 {
46  FaacAudioContext *s = avctx->priv_data;
47 
48 #if FF_API_OLD_ENCODE_AUDIO
49  av_freep(&avctx->coded_frame);
50 #endif
51  av_freep(&avctx->extradata);
53 
54  if (s->faac_handle)
55  faacEncClose(s->faac_handle);
56 
57  return 0;
58 }
59 
60 static const int channel_maps[][6] = {
61  { 2, 0, 1 }, //< C L R
62  { 2, 0, 1, 3 }, //< C L R Cs
63  { 2, 0, 1, 3, 4 }, //< C L R Ls Rs
64  { 2, 0, 1, 4, 5, 3 }, //< C L R Ls Rs LFE
65 };
66 
68 {
69  FaacAudioContext *s = avctx->priv_data;
70  faacEncConfigurationPtr faac_cfg;
71  unsigned long samples_input, max_bytes_output;
72  int ret;
73 
74  /* number of channels */
75  if (avctx->channels < 1 || avctx->channels > 6) {
76  av_log(avctx, AV_LOG_ERROR, "encoding %d channel(s) is not allowed\n", avctx->channels);
77  ret = AVERROR(EINVAL);
78  goto error;
79  }
80 
81  s->faac_handle = faacEncOpen(avctx->sample_rate,
82  avctx->channels,
83  &samples_input, &max_bytes_output);
84  if (!s->faac_handle) {
85  av_log(avctx, AV_LOG_ERROR, "error in faacEncOpen()\n");
86  ret = AVERROR_UNKNOWN;
87  goto error;
88  }
89 
90  /* check faac version */
91  faac_cfg = faacEncGetCurrentConfiguration(s->faac_handle);
92  if (faac_cfg->version != FAAC_CFG_VERSION) {
93  av_log(avctx, AV_LOG_ERROR, "wrong libfaac version (compiled for: %d, using %d)\n", FAAC_CFG_VERSION, faac_cfg->version);
94  ret = AVERROR(EINVAL);
95  goto error;
96  }
97 
98  /* put the options in the configuration struct */
99  switch(avctx->profile) {
100  case FF_PROFILE_AAC_MAIN:
101  faac_cfg->aacObjectType = MAIN;
102  break;
103  case FF_PROFILE_UNKNOWN:
104  case FF_PROFILE_AAC_LOW:
105  faac_cfg->aacObjectType = LOW;
106  break;
107  case FF_PROFILE_AAC_SSR:
108  faac_cfg->aacObjectType = SSR;
109  break;
110  case FF_PROFILE_AAC_LTP:
111  faac_cfg->aacObjectType = LTP;
112  break;
113  default:
114  av_log(avctx, AV_LOG_ERROR, "invalid AAC profile\n");
115  ret = AVERROR(EINVAL);
116  goto error;
117  }
118  faac_cfg->mpegVersion = MPEG4;
119  faac_cfg->useTns = 0;
120  faac_cfg->allowMidside = 1;
121  faac_cfg->bitRate = avctx->bit_rate / avctx->channels;
122  faac_cfg->bandWidth = avctx->cutoff;
123  if(avctx->flags & CODEC_FLAG_QSCALE) {
124  faac_cfg->bitRate = 0;
125  faac_cfg->quantqual = avctx->global_quality / FF_QP2LAMBDA;
126  }
127  faac_cfg->outputFormat = 1;
128  faac_cfg->inputFormat = FAAC_INPUT_16BIT;
129  if (avctx->channels > 2)
130  memcpy(faac_cfg->channel_map, channel_maps[avctx->channels-3],
131  avctx->channels * sizeof(int));
132 
133  avctx->frame_size = samples_input / avctx->channels;
134 
135 #if FF_API_OLD_ENCODE_AUDIO
137  if (!avctx->coded_frame) {
138  ret = AVERROR(ENOMEM);
139  goto error;
140  }
141 #endif
142 
143  /* Set decoder specific info */
144  avctx->extradata_size = 0;
145  if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER) {
146 
147  unsigned char *buffer = NULL;
148  unsigned long decoder_specific_info_size;
149 
150  if (!faacEncGetDecoderSpecificInfo(s->faac_handle, &buffer,
151  &decoder_specific_info_size)) {
152  avctx->extradata = av_malloc(decoder_specific_info_size + FF_INPUT_BUFFER_PADDING_SIZE);
153  if (!avctx->extradata) {
154  ret = AVERROR(ENOMEM);
155  goto error;
156  }
157  avctx->extradata_size = decoder_specific_info_size;
158  memcpy(avctx->extradata, buffer, avctx->extradata_size);
159  faac_cfg->outputFormat = 0;
160  }
161  free(buffer);
162  }
163 
164  if (!faacEncSetConfiguration(s->faac_handle, faac_cfg)) {
165  av_log(avctx, AV_LOG_ERROR, "libfaac doesn't support this output format!\n");
166  ret = AVERROR(EINVAL);
167  goto error;
168  }
169 
170  avctx->delay = FAAC_DELAY_SAMPLES;
171  ff_af_queue_init(avctx, &s->afq);
172 
173  return 0;
174 error:
175  Faac_encode_close(avctx);
176  return ret;
177 }
178 
179 static int Faac_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
180  const AVFrame *frame, int *got_packet_ptr)
181 {
182  FaacAudioContext *s = avctx->priv_data;
183  int bytes_written, ret;
184  int num_samples = frame ? frame->nb_samples : 0;
185  void *samples = frame ? frame->data[0] : NULL;
186 
187  if ((ret = ff_alloc_packet2(avctx, avpkt, (7 + 768) * avctx->channels))) {
188  av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
189  return ret;
190  }
191 
192  bytes_written = faacEncEncode(s->faac_handle, samples,
193  num_samples * avctx->channels,
194  avpkt->data, avpkt->size);
195  if (bytes_written < 0) {
196  av_log(avctx, AV_LOG_ERROR, "faacEncEncode() error\n");
197  return bytes_written;
198  }
199 
200  /* add current frame to the queue */
201  if (frame) {
202  if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
203  return ret;
204  }
205 
206  if (!bytes_written)
207  return 0;
208 
209  /* Get the next frame pts/duration */
210  ff_af_queue_remove(&s->afq, avctx->frame_size, &avpkt->pts,
211  &avpkt->duration);
212 
213  avpkt->size = bytes_written;
214  *got_packet_ptr = 1;
215  return 0;
216 }
217 
218 static const AVProfile profiles[] = {
219  { FF_PROFILE_AAC_MAIN, "Main" },
220  { FF_PROFILE_AAC_LOW, "LC" },
221  { FF_PROFILE_AAC_SSR, "SSR" },
222  { FF_PROFILE_AAC_LTP, "LTP" },
223  { FF_PROFILE_UNKNOWN },
224 };
225 
226 static const uint64_t faac_channel_layouts[] = {
233  0
234 };
235 
237  .name = "libfaac",
238  .type = AVMEDIA_TYPE_AUDIO,
239  .id = AV_CODEC_ID_AAC,
240  .priv_data_size = sizeof(FaacAudioContext),
242  .encode2 = Faac_encode_frame,
245  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
247  .long_name = NULL_IF_CONFIG_SMALL("libfaac AAC (Advanced Audio Coding)"),
248  .profiles = NULL_IF_CONFIG_SMALL(profiles),
249  .channel_layouts = faac_channel_layouts,
250 };