• Main Page
  • Related Pages
  • Modules
  • Data Structures
  • Files
  • File List
  • Globals

libavcodec/libopencore-amr.c

Go to the documentation of this file.
00001 /*
00002  * AMR Audio decoder stub
00003  * Copyright (c) 2003 the ffmpeg project
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 
00022 #include "avcodec.h"
00023 #include "libavutil/avstring.h"
00024 #include "libavutil/opt.h"
00025 
00026 static void amr_decode_fix_avctx(AVCodecContext *avctx)
00027 {
00028     const int is_amr_wb = 1 + (avctx->codec_id == CODEC_ID_AMR_WB);
00029 
00030     if (!avctx->sample_rate)
00031         avctx->sample_rate = 8000 * is_amr_wb;
00032 
00033     if (!avctx->channels)
00034         avctx->channels = 1;
00035 
00036     avctx->frame_size = 160 * is_amr_wb;
00037     avctx->sample_fmt = AV_SAMPLE_FMT_S16;
00038 }
00039 
00040 #if CONFIG_LIBOPENCORE_AMRNB
00041 
00042 #include <opencore-amrnb/interf_dec.h>
00043 #include <opencore-amrnb/interf_enc.h>
00044 
00045 /* Common code for fixed and float version*/
00046 typedef struct AMR_bitrates {
00047     int       rate;
00048     enum Mode mode;
00049 } AMR_bitrates;
00050 
00051 /* Match desired bitrate */
00052 static int get_bitrate_mode(int bitrate, void *log_ctx)
00053 {
00054     /* make the correspondance between bitrate and mode */
00055     static const AMR_bitrates rates[] = {
00056         { 4750, MR475 }, { 5150, MR515 }, {  5900, MR59  }, {  6700, MR67  },
00057         { 7400, MR74 },  { 7950, MR795 }, { 10200, MR102 }, { 12200, MR122 }
00058     };
00059     int i, best = -1, min_diff = 0;
00060     char log_buf[200];
00061 
00062     for (i = 0; i < 8; i++) {
00063         if (rates[i].rate == bitrate)
00064             return rates[i].mode;
00065         if (best < 0 || abs(rates[i].rate - bitrate) < min_diff) {
00066             best     = i;
00067             min_diff = abs(rates[i].rate - bitrate);
00068         }
00069     }
00070     /* no bitrate matching exactly, log a warning */
00071     snprintf(log_buf, sizeof(log_buf), "bitrate not supported: use one of ");
00072     for (i = 0; i < 8; i++)
00073         av_strlcatf(log_buf, sizeof(log_buf), "%.2fk, ", rates[i].rate    / 1000.f);
00074     av_strlcatf(log_buf, sizeof(log_buf), "using %.2fk", rates[best].rate / 1000.f);
00075     av_log(log_ctx, AV_LOG_WARNING, "%s\n", log_buf);
00076 
00077     return best;
00078 }
00079 
00080 typedef struct AMRContext {
00081     AVClass *av_class;
00082     AVFrame frame;
00083     void *dec_state;
00084     void *enc_state;
00085     int   enc_bitrate;
00086     int   enc_mode;
00087     int   enc_dtx;
00088 } AMRContext;
00089 
00090 static const AVOption options[] = {
00091     { "dtx", "Allow DTX (generate comfort noise)", offsetof(AMRContext, enc_dtx), AV_OPT_TYPE_INT, { 0 }, 0, 1, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
00092     { NULL }
00093 };
00094 
00095 static const AVClass class = {
00096     "libopencore_amrnb", av_default_item_name, options, LIBAVUTIL_VERSION_INT
00097 };
00098 
00099 static av_cold int amr_nb_decode_init(AVCodecContext *avctx)
00100 {
00101     AMRContext *s  = avctx->priv_data;
00102 
00103     s->dec_state   = Decoder_Interface_init();
00104     if (!s->dec_state) {
00105         av_log(avctx, AV_LOG_ERROR, "Decoder_Interface_init error\n");
00106         return -1;
00107     }
00108 
00109     amr_decode_fix_avctx(avctx);
00110 
00111     if (avctx->channels > 1) {
00112         av_log(avctx, AV_LOG_ERROR, "amr_nb: multichannel decoding not supported\n");
00113         return AVERROR(ENOSYS);
00114     }
00115 
00116     avcodec_get_frame_defaults(&s->frame);
00117     avctx->coded_frame = &s->frame;
00118 
00119     return 0;
00120 }
00121 
00122 static av_cold int amr_nb_decode_close(AVCodecContext *avctx)
00123 {
00124     AMRContext *s = avctx->priv_data;
00125 
00126     Decoder_Interface_exit(s->dec_state);
00127 
00128     return 0;
00129 }
00130 
00131 static int amr_nb_decode_frame(AVCodecContext *avctx, void *data,
00132                                int *got_frame_ptr, AVPacket *avpkt)
00133 {
00134     const uint8_t *buf = avpkt->data;
00135     int buf_size       = avpkt->size;
00136     AMRContext *s      = avctx->priv_data;
00137     static const uint8_t block_size[16] = { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 };
00138     enum Mode dec_mode;
00139     int packet_size, ret;
00140 
00141     av_dlog(avctx, "amr_decode_frame buf=%p buf_size=%d frame_count=%d!!\n",
00142             buf, buf_size, avctx->frame_number);
00143 
00144     /* get output buffer */
00145     s->frame.nb_samples = 160;
00146     if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
00147         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00148         return ret;
00149     }
00150 
00151     dec_mode    = (buf[0] >> 3) & 0x000F;
00152     packet_size = block_size[dec_mode] + 1;
00153 
00154     if (packet_size > buf_size) {
00155         av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
00156                buf_size, packet_size);
00157         return AVERROR_INVALIDDATA;
00158     }
00159 
00160     av_dlog(avctx, "packet_size=%d buf= 0x%X %X %X %X\n",
00161               packet_size, buf[0], buf[1], buf[2], buf[3]);
00162     /* call decoder */
00163     Decoder_Interface_Decode(s->dec_state, buf, (short *)s->frame.data[0], 0);
00164 
00165     *got_frame_ptr   = 1;
00166     *(AVFrame *)data = s->frame;
00167 
00168     return packet_size;
00169 }
00170 
00171 AVCodec ff_libopencore_amrnb_decoder = {
00172     .name           = "libopencore_amrnb",
00173     .type           = AVMEDIA_TYPE_AUDIO,
00174     .id             = CODEC_ID_AMR_NB,
00175     .priv_data_size = sizeof(AMRContext),
00176     .init           = amr_nb_decode_init,
00177     .close          = amr_nb_decode_close,
00178     .decode         = amr_nb_decode_frame,
00179     .capabilities   = CODEC_CAP_DR1,
00180     .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Narrow-Band"),
00181 };
00182 
00183 static av_cold int amr_nb_encode_init(AVCodecContext *avctx)
00184 {
00185     AMRContext *s = avctx->priv_data;
00186 
00187     if (avctx->sample_rate != 8000) {
00188         av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
00189         return AVERROR(ENOSYS);
00190     }
00191 
00192     if (avctx->channels != 1) {
00193         av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
00194         return AVERROR(ENOSYS);
00195     }
00196 
00197     avctx->frame_size  = 160;
00198     avctx->coded_frame = avcodec_alloc_frame();
00199 
00200     s->enc_state = Encoder_Interface_init(s->enc_dtx);
00201     if (!s->enc_state) {
00202         av_log(avctx, AV_LOG_ERROR, "Encoder_Interface_init error\n");
00203         return -1;
00204     }
00205 
00206     s->enc_mode    = get_bitrate_mode(avctx->bit_rate, avctx);
00207     s->enc_bitrate = avctx->bit_rate;
00208 
00209     return 0;
00210 }
00211 
00212 static av_cold int amr_nb_encode_close(AVCodecContext *avctx)
00213 {
00214     AMRContext *s = avctx->priv_data;
00215 
00216     Encoder_Interface_exit(s->enc_state);
00217     av_freep(&avctx->coded_frame);
00218     return 0;
00219 }
00220 
00221 static int amr_nb_encode_frame(AVCodecContext *avctx,
00222                                unsigned char *frame/*out*/,
00223                                int buf_size, void *data/*in*/)
00224 {
00225     AMRContext *s = avctx->priv_data;
00226     int written;
00227 
00228     if (s->enc_bitrate != avctx->bit_rate) {
00229         s->enc_mode    = get_bitrate_mode(avctx->bit_rate, avctx);
00230         s->enc_bitrate = avctx->bit_rate;
00231     }
00232 
00233     written = Encoder_Interface_Encode(s->enc_state, s->enc_mode, data,
00234                                        frame, 0);
00235     av_dlog(avctx, "amr_nb_encode_frame encoded %u bytes, bitrate %u, first byte was %#02x\n",
00236             written, s->enc_mode, frame[0]);
00237 
00238     return written;
00239 }
00240 
00241 AVCodec ff_libopencore_amrnb_encoder = {
00242     .name           = "libopencore_amrnb",
00243     .type           = AVMEDIA_TYPE_AUDIO,
00244     .id             = CODEC_ID_AMR_NB,
00245     .priv_data_size = sizeof(AMRContext),
00246     .init           = amr_nb_encode_init,
00247     .encode         = amr_nb_encode_frame,
00248     .close          = amr_nb_encode_close,
00249     .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
00250     .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Narrow-Band"),
00251     .priv_class = &class,
00252 };
00253 
00254 #endif
00255 
00256 /* -----------AMR wideband ------------*/
00257 #if CONFIG_LIBOPENCORE_AMRWB
00258 
00259 #include <opencore-amrwb/dec_if.h>
00260 #include <opencore-amrwb/if_rom.h>
00261 
00262 typedef struct AMRWBContext {
00263     AVFrame frame;
00264     void  *state;
00265 } AMRWBContext;
00266 
00267 static av_cold int amr_wb_decode_init(AVCodecContext *avctx)
00268 {
00269     AMRWBContext *s = avctx->priv_data;
00270 
00271     s->state        = D_IF_init();
00272 
00273     amr_decode_fix_avctx(avctx);
00274 
00275     if (avctx->channels > 1) {
00276         av_log(avctx, AV_LOG_ERROR, "amr_wb: multichannel decoding not supported\n");
00277         return AVERROR(ENOSYS);
00278     }
00279 
00280     avcodec_get_frame_defaults(&s->frame);
00281     avctx->coded_frame = &s->frame;
00282 
00283     return 0;
00284 }
00285 
00286 static int amr_wb_decode_frame(AVCodecContext *avctx, void *data,
00287                                int *got_frame_ptr, AVPacket *avpkt)
00288 {
00289     const uint8_t *buf = avpkt->data;
00290     int buf_size       = avpkt->size;
00291     AMRWBContext *s    = avctx->priv_data;
00292     int mode, ret;
00293     int packet_size;
00294     static const uint8_t block_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
00295 
00296     /* get output buffer */
00297     s->frame.nb_samples = 320;
00298     if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
00299         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00300         return ret;
00301     }
00302 
00303     mode        = (buf[0] >> 3) & 0x000F;
00304     packet_size = block_size[mode];
00305 
00306     if (packet_size > buf_size) {
00307         av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
00308                buf_size, packet_size + 1);
00309         return AVERROR_INVALIDDATA;
00310     }
00311 
00312     D_IF_decode(s->state, buf, (short *)s->frame.data[0], _good_frame);
00313 
00314     *got_frame_ptr   = 1;
00315     *(AVFrame *)data = s->frame;
00316 
00317     return packet_size;
00318 }
00319 
00320 static int amr_wb_decode_close(AVCodecContext *avctx)
00321 {
00322     AMRWBContext *s = avctx->priv_data;
00323 
00324     D_IF_exit(s->state);
00325     return 0;
00326 }
00327 
00328 AVCodec ff_libopencore_amrwb_decoder = {
00329     .name           = "libopencore_amrwb",
00330     .type           = AVMEDIA_TYPE_AUDIO,
00331     .id             = CODEC_ID_AMR_WB,
00332     .priv_data_size = sizeof(AMRWBContext),
00333     .init           = amr_wb_decode_init,
00334     .close          = amr_wb_decode_close,
00335     .decode         = amr_wb_decode_frame,
00336     .capabilities   = CODEC_CAP_DR1,
00337     .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Wide-Band"),
00338 };
00339 
00340 #endif /* CONFIG_LIBOPENCORE_AMRWB */
Generated on Fri Feb 1 2013 14:34:37 for FFmpeg by doxygen 1.7.1