FFmpeg: libavcodec/libfaac.c Source File

00001 /*
00002  * Interface to libfaac for aac encoding
00003  * Copyright (c) 2002 Gildas Bazin <gbazin@netcourrier.com>
00004  *
00005  * This file is part of FFmpeg.
00006  *
00007  * FFmpeg is free software; you can redistribute it and/or
00008  * modify it under the terms of the GNU Lesser General Public
00009  * License as published by the Free Software Foundation; either
00010  * version 2.1 of the License, or (at your option) any later version.
00011  *
00012  * FFmpeg is distributed in the hope that it will be useful,
00013  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00014  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015  * Lesser General Public License for more details.
00016  *
00017  * You should have received a copy of the GNU Lesser General Public
00018  * License along with FFmpeg; if not, write to the Free Software
00019  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00020  */
00021 
00027 #include <faac.h>
00028 
00029 #include "libavutil/channel_layout.h"
00030 #include "libavutil/common.h"
00031 #include "avcodec.h"
00032 #include "audio_frame_queue.h"
00033 #include "internal.h"
00034 
00035 
00036 /* libfaac has an encoder delay of 1024 samples */
00037 #define FAAC_DELAY_SAMPLES 1024
00038 
00039 typedef struct FaacAudioContext {
00040     faacEncHandle faac_handle;
00041     AudioFrameQueue afq;
00042 } FaacAudioContext;
00043 
00044 static av_cold int Faac_encode_close(AVCodecContext *avctx)
00045 {
00046     FaacAudioContext *s = avctx->priv_data;
00047 
00048 #if FF_API_OLD_ENCODE_AUDIO
00049     av_freep(&avctx->coded_frame);
00050 #endif
00051     av_freep(&avctx->extradata);
00052     ff_af_queue_close(&s->afq);
00053 
00054     if (s->faac_handle)
00055         faacEncClose(s->faac_handle);
00056 
00057     return 0;
00058 }
00059 
00060 static const int channel_maps[][6] = {
00061     { 2, 0, 1 },          //< C L R
00062     { 2, 0, 1, 3 },       //< C L R Cs
00063     { 2, 0, 1, 3, 4 },    //< C L R Ls Rs
00064     { 2, 0, 1, 4, 5, 3 }, //< C L R Ls Rs LFE
00065 };
00066 
00067 static av_cold int Faac_encode_init(AVCodecContext *avctx)
00068 {
00069     FaacAudioContext *s = avctx->priv_data;
00070     faacEncConfigurationPtr faac_cfg;
00071     unsigned long samples_input, max_bytes_output;
00072     int ret;
00073 
00074     /* number of channels */
00075     if (avctx->channels < 1 || avctx->channels > 6) {
00076         av_log(avctx, AV_LOG_ERROR, "encoding %d channel(s) is not allowed\n", avctx->channels);
00077         ret = AVERROR(EINVAL);
00078         goto error;
00079     }
00080 
00081     s->faac_handle = faacEncOpen(avctx->sample_rate,
00082                                  avctx->channels,
00083                                  &samples_input, &max_bytes_output);
00084     if (!s->faac_handle) {
00085         av_log(avctx, AV_LOG_ERROR, "error in faacEncOpen()\n");
00086         ret = AVERROR_UNKNOWN;
00087         goto error;
00088     }
00089 
00090     /* check faac version */
00091     faac_cfg = faacEncGetCurrentConfiguration(s->faac_handle);
00092     if (faac_cfg->version != FAAC_CFG_VERSION) {
00093         av_log(avctx, AV_LOG_ERROR, "wrong libfaac version (compiled for: %d, using %d)\n", FAAC_CFG_VERSION, faac_cfg->version);
00094         ret = AVERROR(EINVAL);
00095         goto error;
00096     }
00097 
00098     /* put the options in the configuration struct */
00099     switch(avctx->profile) {
00100         case FF_PROFILE_AAC_MAIN:
00101             faac_cfg->aacObjectType = MAIN;
00102             break;
00103         case FF_PROFILE_UNKNOWN:
00104         case FF_PROFILE_AAC_LOW:
00105             faac_cfg->aacObjectType = LOW;
00106             break;
00107         case FF_PROFILE_AAC_SSR:
00108             faac_cfg->aacObjectType = SSR;
00109             break;
00110         case FF_PROFILE_AAC_LTP:
00111             faac_cfg->aacObjectType = LTP;
00112             break;
00113         default:
00114             av_log(avctx, AV_LOG_ERROR, "invalid AAC profile\n");
00115             ret = AVERROR(EINVAL);
00116             goto error;
00117     }
00118     faac_cfg->mpegVersion = MPEG4;
00119     faac_cfg->useTns = 0;
00120     faac_cfg->allowMidside = 1;
00121     faac_cfg->bitRate = avctx->bit_rate / avctx->channels;
00122     faac_cfg->bandWidth = avctx->cutoff;
00123     if(avctx->flags & CODEC_FLAG_QSCALE) {
00124         faac_cfg->bitRate = 0;
00125         faac_cfg->quantqual = avctx->global_quality / FF_QP2LAMBDA;
00126     }
00127     faac_cfg->outputFormat = 1;
00128     faac_cfg->inputFormat = FAAC_INPUT_16BIT;
00129     if (avctx->channels > 2)
00130         memcpy(faac_cfg->channel_map, channel_maps[avctx->channels-3],
00131                avctx->channels * sizeof(int));
00132 
00133     avctx->frame_size = samples_input / avctx->channels;
00134 
00135 #if FF_API_OLD_ENCODE_AUDIO
00136     avctx->coded_frame= avcodec_alloc_frame();
00137     if (!avctx->coded_frame) {
00138         ret = AVERROR(ENOMEM);
00139         goto error;
00140     }
00141 #endif
00142 
00143     /* Set decoder specific info */
00144     avctx->extradata_size = 0;
00145     if (avctx->flags & CODEC_FLAG_GLOBAL_HEADER) {
00146 
00147         unsigned char *buffer = NULL;
00148         unsigned long decoder_specific_info_size;
00149 
00150         if (!faacEncGetDecoderSpecificInfo(s->faac_handle, &buffer,
00151                                            &decoder_specific_info_size)) {
00152             avctx->extradata = av_malloc(decoder_specific_info_size + FF_INPUT_BUFFER_PADDING_SIZE);
00153             if (!avctx->extradata) {
00154                 ret = AVERROR(ENOMEM);
00155                 goto error;
00156             }
00157             avctx->extradata_size = decoder_specific_info_size;
00158             memcpy(avctx->extradata, buffer, avctx->extradata_size);
00159             faac_cfg->outputFormat = 0;
00160         }
00161         free(buffer);
00162     }
00163 
00164     if (!faacEncSetConfiguration(s->faac_handle, faac_cfg)) {
00165         av_log(avctx, AV_LOG_ERROR, "libfaac doesn't support this output format!\n");
00166         ret = AVERROR(EINVAL);
00167         goto error;
00168     }
00169 
00170     avctx->delay = FAAC_DELAY_SAMPLES;
00171     ff_af_queue_init(avctx, &s->afq);
00172 
00173     return 0;
00174 error:
00175     Faac_encode_close(avctx);
00176     return ret;
00177 }
00178 
00179 static int Faac_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
00180                              const AVFrame *frame, int *got_packet_ptr)
00181 {
00182     FaacAudioContext *s = avctx->priv_data;
00183     int bytes_written, ret;
00184     int num_samples  = frame ? frame->nb_samples : 0;
00185     void *samples    = frame ? frame->data[0]    : NULL;
00186 
00187     if ((ret = ff_alloc_packet2(avctx, avpkt, (7 + 768) * avctx->channels))) {
00188         av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
00189         return ret;
00190     }
00191 
00192     bytes_written = faacEncEncode(s->faac_handle, samples,
00193                                   num_samples * avctx->channels,
00194                                   avpkt->data, avpkt->size);
00195     if (bytes_written < 0) {
00196         av_log(avctx, AV_LOG_ERROR, "faacEncEncode() error\n");
00197         return bytes_written;
00198     }
00199 
00200     /* add current frame to the queue */
00201     if (frame) {
00202         if ((ret = ff_af_queue_add(&s->afq, frame) < 0))
00203             return ret;
00204     }
00205 
00206     if (!bytes_written)
00207         return 0;
00208 
00209     /* Get the next frame pts/duration */
00210     ff_af_queue_remove(&s->afq, avctx->frame_size, &avpkt->pts,
00211                        &avpkt->duration);
00212 
00213     avpkt->size = bytes_written;
00214     *got_packet_ptr = 1;
00215     return 0;
00216 }
00217 
00218 static const AVProfile profiles[] = {
00219     { FF_PROFILE_AAC_MAIN, "Main" },
00220     { FF_PROFILE_AAC_LOW,  "LC"   },
00221     { FF_PROFILE_AAC_SSR,  "SSR"  },
00222     { FF_PROFILE_AAC_LTP,  "LTP"  },
00223     { FF_PROFILE_UNKNOWN },
00224 };
00225 
00226 static const uint64_t faac_channel_layouts[] = {
00227     AV_CH_LAYOUT_MONO,
00228     AV_CH_LAYOUT_STEREO,
00229     AV_CH_LAYOUT_SURROUND,
00230     AV_CH_LAYOUT_4POINT0,
00231     AV_CH_LAYOUT_5POINT0_BACK,
00232     AV_CH_LAYOUT_5POINT1_BACK,
00233     0
00234 };
00235 
00236 AVCodec ff_libfaac_encoder = {
00237     .name           = "libfaac",
00238     .type           = AVMEDIA_TYPE_AUDIO,
00239     .id             = AV_CODEC_ID_AAC,
00240     .priv_data_size = sizeof(FaacAudioContext),
00241     .init           = Faac_encode_init,
00242     .encode2        = Faac_encode_frame,
00243     .close          = Faac_encode_close,
00244     .capabilities   = CODEC_CAP_SMALL_LAST_FRAME | CODEC_CAP_DELAY,
00245     .sample_fmts    = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
00246                                                      AV_SAMPLE_FMT_NONE },
00247     .long_name      = NULL_IF_CONFIG_SMALL("libfaac AAC (Advanced Audio Coding)"),
00248     .profiles       = NULL_IF_CONFIG_SMALL(profiles),
00249     .channel_layouts = faac_channel_layouts,
00250 };