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📄 libamr.c

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/* * AMR Audio decoder stub * Copyright (c) 2003 the ffmpeg project * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** @file * Adaptive Multi-Rate (AMR) Audio decoder stub. * * This code implements both an AMR-NarrowBand (AMR-NB) and an AMR-WideBand * (AMR-WB) audio encoder/decoder through external reference code from * http://www.3gpp.org/. The license of the code from 3gpp is unclear so you * have to download the code separately. Two versions exists: One fixed-point * and one floating-point. For some reason the float encoder is significantly * faster at least on a P4 1.5GHz (0.9s instead of 9.9s on a 30s audio clip * at MR102). Both float and fixed point are supported for AMR-NB, but only * float for AMR-WB. * * \section AMR-NB * * \subsection Float * The float version (default) can be downloaded from: * http://www.3gpp.org/ftp/Specs/archive/26_series/26.104/26104-610.zip * * \subsection Fixed-point * The fixed-point (TS26.073) can be downloaded from: * http://www.3gpp.org/ftp/Specs/archive/26_series/26.073/26073-600.zip * * \subsection Specification * The specification for AMR-NB can be found in TS 26.071 * (http://www.3gpp.org/ftp/Specs/html-info/26071.htm) and some other * info at http://www.3gpp.org/ftp/Specs/html-info/26-series.htm. * * \section AMR-WB * * \subsection Float * The reference code can be downloaded from: * http://www.3gpp.org/ftp/Specs/archive/26_series/26.204/26204-600.zip * * \subsection Fixed-point * If someone wants to use the fixed point version it can be downloaded from: * http://www.3gpp.org/ftp/Specs/archive/26_series/26.173/26173-571.zip. * * \subsection Specification * The specification for AMR-WB can be found in TS 26.171 * (http://www.3gpp.org/ftp/Specs/html-info/26171.htm) and some other * info at http://www.3gpp.org/ftp/Specs/html-info/26-series.htm. * */#include "avcodec.h"#ifdef CONFIG_LIBAMR_NB_FIXED#define MMS_IO#include "amr/sp_dec.h"#include "amr/d_homing.h"#include "amr/typedef.h"#include "amr/sp_enc.h"#include "amr/sid_sync.h"#include "amr/e_homing.h"#else#include <amrnb/interf_dec.h>#include <amrnb/interf_enc.h>#endifstatic const char *nb_bitrate_unsupported =    "bitrate not supported: use one of 4.75k, 5.15k, 5.9k, 6.7k, 7.4k, 7.95k, 10.2k or 12.2k\n";static const char *wb_bitrate_unsupported =    "bitrate not supported: use one of 6.6k, 8.85k, 12.65k, 14.25k, 15.85k, 18.25k, 19.85k, 23.05k, or 23.85k\n";/* Common code for fixed and float version*/typedef struct AMR_bitrates{    int rate;    enum Mode mode;} AMR_bitrates;/* Match desired bitrate */static int getBitrateMode(int bitrate){    /* make the correspondance between bitrate and mode */#ifdef __CW32__    AMR_bitrates rates[8];#else    AMR_bitrates rates[]={ {4750,MR475},                           {5150,MR515},                           {5900,MR59},                           {6700,MR67},                           {7400,MR74},                           {7950,MR795},                           {10200,MR102},                           {12200,MR122},                         };#endif    int i;    for(i=0;i<8;i++)    {        if(rates[i].rate==bitrate)        {            return rates[i].mode;        }    }    /* no bitrate matching, return an error */    return -1;}static void amr_decode_fix_avctx(AVCodecContext * avctx){    const int is_amr_wb = 1 + (avctx->codec_id == CODEC_ID_AMR_WB);    if(avctx->sample_rate == 0)    {        avctx->sample_rate = 8000 * is_amr_wb;    }    if(avctx->channels == 0)    {        avctx->channels = 1;    }    avctx->frame_size = 160 * is_amr_wb;}#ifdef CONFIG_LIBAMR_NB_FIXED/* fixed point version*//* frame size in serial bitstream file (frame type + serial stream + flags) */#define SERIAL_FRAMESIZE (1+MAX_SERIAL_SIZE+5)typedef struct AMRContext {    int frameCount;    Speech_Decode_FrameState *speech_decoder_state;    enum RXFrameType rx_type;    enum Mode mode;    Word16 reset_flag;    Word16 reset_flag_old;    int enc_bitrate;    Speech_Encode_FrameState *enstate;    sid_syncState *sidstate;    enum TXFrameType tx_frametype;} AMRContext;static int amr_nb_decode_init(AVCodecContext * avctx){    AMRContext *s = avctx->priv_data;    s->frameCount=0;    s->speech_decoder_state=NULL;    s->rx_type = (enum RXFrameType)0;    s->mode= (enum Mode)0;    s->reset_flag=0;    s->reset_flag_old=1;    if(Speech_Decode_Frame_init(&s->speech_decoder_state, "Decoder"))    {        av_log(avctx, AV_LOG_ERROR, "Speech_Decode_Frame_init error\n");        return -1;    }    amr_decode_fix_avctx(avctx);    if(avctx->channels > 1)    {        av_log(avctx, AV_LOG_ERROR, "amr_nb: multichannel decoding not supported\n");        return -1;    }    return 0;}static int amr_nb_encode_init(AVCodecContext * avctx){    AMRContext *s = avctx->priv_data;    s->frameCount=0;    s->speech_decoder_state=NULL;    s->rx_type = (enum RXFrameType)0;    s->mode= (enum Mode)0;    s->reset_flag=0;    s->reset_flag_old=1;    if(avctx->sample_rate!=8000)    {        av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");        return -1;    }    if(avctx->channels!=1)    {        av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");        return -1;    }    avctx->frame_size=160;    avctx->coded_frame= avcodec_alloc_frame();    if(Speech_Encode_Frame_init(&s->enstate, 0, "encoder") || sid_sync_init (&s->sidstate))    {        av_log(avctx, AV_LOG_ERROR, "Speech_Encode_Frame_init error\n");        return -1;    }    if((s->enc_bitrate=getBitrateMode(avctx->bit_rate))<0)    {        av_log(avctx, AV_LOG_ERROR, nb_bitrate_unsupported);        return -1;    }    return 0;}static int amr_nb_encode_close(AVCodecContext * avctx){    AMRContext *s = avctx->priv_data;    Speech_Encode_Frame_exit(&s->enstate);    sid_sync_exit (&s->sidstate);    av_freep(&avctx->coded_frame);    return 0;}static int amr_nb_decode_close(AVCodecContext * avctx){    AMRContext *s = avctx->priv_data;    Speech_Decode_Frame_exit(&s->speech_decoder_state);    return 0;}static int amr_nb_decode_frame(AVCodecContext * avctx,            void *data, int *data_size,            uint8_t * buf, int buf_size){    AMRContext *s = avctx->priv_data;    uint8_t*amrData=buf;    int offset=0;    UWord8 toc, q, ft;    Word16 serial[SERIAL_FRAMESIZE];   /* coded bits */    Word16 *synth;    UWord8 *packed_bits;    static Word16 packed_size[16] = {12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0};    int i;    //printf("amr_decode_frame data_size=%i buf=0x%X buf_size=%d frameCount=%d!!\n",*data_size,buf,buf_size,s->frameCount);    synth=data;    toc=amrData[offset];    /* read rest of the frame based on ToC byte */    q  = (toc >> 2) & 0x01;    ft = (toc >> 3) & 0x0F;    //printf("offset=%d, packet_size=%d amrData= 0x%X %X %X %X\n",offset,packed_size[ft],amrData[offset],amrData[offset+1],amrData[offset+2],amrData[offset+3]);    offset++;    packed_bits=amrData+offset;    offset+=packed_size[ft];    //Unsort and unpack bits    s->rx_type = UnpackBits(q, ft, packed_bits, &s->mode, &serial[1]);    //We have a new frame    s->frameCount++;    if (s->rx_type == RX_NO_DATA)    {        s->mode = s->speech_decoder_state->prev_mode;    }    else {        s->speech_decoder_state->prev_mode = s->mode;    }    /* if homed: check if this frame is another homing frame */    if (s->reset_flag_old == 1)    {        /* only check until end of first subframe */        s->reset_flag = decoder_homing_frame_test_first(&serial[1], s->mode);    }    /* produce encoder homing frame if homed & input=decoder homing frame */    if ((s->reset_flag != 0) && (s->reset_flag_old != 0))    {        for (i = 0; i < L_FRAME; i++)        {            synth[i] = EHF_MASK;        }    }    else    {        /* decode frame */        Speech_Decode_Frame(s->speech_decoder_state, s->mode, &serial[1], s->rx_type, synth);    }    //Each AMR-frame results in 160 16-bit samples    *data_size=160*2;    /* if not homed: check whether current frame is a homing frame */    if (s->reset_flag_old == 0)    {        /* check whole frame */        s->reset_flag = decoder_homing_frame_test(&serial[1], s->mode);    }    /* reset decoder if current frame is a homing frame */    if (s->reset_flag != 0)    {        Speech_Decode_Frame_reset(s->speech_decoder_state);    }    s->reset_flag_old = s->reset_flag;    return offset;}static int amr_nb_encode_frame(AVCodecContext *avctx,                            unsigned char *frame/*out*/, int buf_size, void *data/*in*/){    short serial_data[250] = {0};    AMRContext *s = avctx->priv_data;    int written;    s->reset_flag = encoder_homing_frame_test(data);    Speech_Encode_Frame(s->enstate, s->enc_bitrate, data, &serial_data[1], &s->mode);    /* add frame type and mode */    sid_sync (s->sidstate, s->mode, &s->tx_frametype);    written = PackBits(s->mode, s->enc_bitrate, s->tx_frametype, &serial_data[1], frame);    if (s->reset_flag != 0)    {        Speech_Encode_Frame_reset(s->enstate);        sid_sync_reset(s->sidstate);    }    return written;}#elif defined(CONFIG_LIBAMR_NB) /* Float point version*/typedef struct AMRContext {    int frameCount;    void * decState;    int *enstate;    int enc_bitrate;} AMRContext;static int amr_nb_decode_init(AVCodecContext * avctx){    AMRContext *s = avctx->priv_data;    s->frameCount=0;    s->decState=Decoder_Interface_init();    if(!s->decState)    {        av_log(avctx, AV_LOG_ERROR, "Decoder_Interface_init error\r\n");        return -1;    }    amr_decode_fix_avctx(avctx);    if(avctx->channels > 1)

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