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📄 libvorbis.c

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/* * copyright (c) 2002 Mark Hills <mark@pogo.org.uk> * * 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 oggvorbis.c * Ogg Vorbis codec support via libvorbisenc. * @author Mark Hills <mark@pogo.org.uk> */#include <vorbis/vorbisenc.h>#include "avcodec.h"#include "bytestream.h"#undef NDEBUG#include <assert.h>#define OGGVORBIS_FRAME_SIZE 64#define BUFFER_SIZE (1024*64)typedef struct OggVorbisContext {    vorbis_info vi ;    vorbis_dsp_state vd ;    vorbis_block vb ;    uint8_t buffer[BUFFER_SIZE];    int buffer_index;    /* decoder */    vorbis_comment vc ;    ogg_packet op;} OggVorbisContext ;static int oggvorbis_init_encoder(vorbis_info *vi, AVCodecContext *avccontext) {    double cfreq;    if(avccontext->flags & CODEC_FLAG_QSCALE) {        /* variable bitrate */        if(vorbis_encode_setup_vbr(vi, avccontext->channels,                avccontext->sample_rate,                avccontext->global_quality / (float)FF_QP2LAMBDA))            return -1;    } else {        /* constant bitrate */        if(vorbis_encode_setup_managed(vi, avccontext->channels,                avccontext->sample_rate, -1, avccontext->bit_rate, -1))            return -1;#ifdef OGGVORBIS_VBR_BY_ESTIMATE        /* variable bitrate by estimate */        if(vorbis_encode_ctl(vi, OV_ECTL_RATEMANAGE_AVG, NULL))            return -1;#endif    }    /* cutoff frequency */    if(avccontext->cutoff > 0) {        cfreq = avccontext->cutoff / 1000.0;        if(vorbis_encode_ctl(vi, OV_ECTL_LOWPASS_SET, &cfreq))            return -1;    }    return vorbis_encode_setup_init(vi);}static av_cold int oggvorbis_encode_init(AVCodecContext *avccontext) {    OggVorbisContext *context = avccontext->priv_data ;    ogg_packet header, header_comm, header_code;    uint8_t *p;    unsigned int offset, len;    vorbis_info_init(&context->vi) ;    if(oggvorbis_init_encoder(&context->vi, avccontext) < 0) {        av_log(avccontext, AV_LOG_ERROR, "oggvorbis_encode_init: init_encoder failed") ;        return -1 ;    }    vorbis_analysis_init(&context->vd, &context->vi) ;    vorbis_block_init(&context->vd, &context->vb) ;    vorbis_comment_init(&context->vc);    vorbis_comment_add_tag(&context->vc, "encoder", LIBAVCODEC_IDENT) ;    vorbis_analysis_headerout(&context->vd, &context->vc, &header,                                &header_comm, &header_code);    len = header.bytes + header_comm.bytes +  header_code.bytes;    avccontext->extradata_size= 64 + len + len/255;    p = avccontext->extradata= av_mallocz(avccontext->extradata_size);    p[0] = 2;    offset = 1;    offset += av_xiphlacing(&p[offset], header.bytes);    offset += av_xiphlacing(&p[offset], header_comm.bytes);    memcpy(&p[offset], header.packet, header.bytes);    offset += header.bytes;    memcpy(&p[offset], header_comm.packet, header_comm.bytes);    offset += header_comm.bytes;    memcpy(&p[offset], header_code.packet, header_code.bytes);    offset += header_code.bytes;    avccontext->extradata_size = offset;    avccontext->extradata= av_realloc(avccontext->extradata, avccontext->extradata_size);/*    vorbis_block_clear(&context->vb);    vorbis_dsp_clear(&context->vd);    vorbis_info_clear(&context->vi);*/    vorbis_comment_clear(&context->vc);    avccontext->frame_size = OGGVORBIS_FRAME_SIZE ;    avccontext->coded_frame= avcodec_alloc_frame();    avccontext->coded_frame->key_frame= 1;    return 0 ;}static int oggvorbis_encode_frame(AVCodecContext *avccontext,                                  unsigned char *packets,                           int buf_size, void *data){    OggVorbisContext *context = avccontext->priv_data ;    float **buffer ;    ogg_packet op ;    signed short *audio = data ;    int l, samples = data ? OGGVORBIS_FRAME_SIZE : 0;    buffer = vorbis_analysis_buffer(&context->vd, samples) ;    if(context->vi.channels == 1) {        for(l = 0 ; l < samples ; l++)            buffer[0][l]=audio[l]/32768.f;    } else {        for(l = 0 ; l < samples ; l++){            buffer[0][l]=audio[l*2]/32768.f;            buffer[1][l]=audio[l*2+1]/32768.f;        }    }    vorbis_analysis_wrote(&context->vd, samples) ;    while(vorbis_analysis_blockout(&context->vd, &context->vb) == 1) {        vorbis_analysis(&context->vb, NULL);        vorbis_bitrate_addblock(&context->vb) ;        while(vorbis_bitrate_flushpacket(&context->vd, &op)) {            /* i'd love to say the following line is a hack, but sadly it's             * not, apparently the end of stream decision is in libogg. */            if(op.bytes==1)                continue;            memcpy(context->buffer + context->buffer_index, &op, sizeof(ogg_packet));            context->buffer_index += sizeof(ogg_packet);            memcpy(context->buffer + context->buffer_index, op.packet, op.bytes);            context->buffer_index += op.bytes;//            av_log(avccontext, AV_LOG_DEBUG, "e%d / %d\n", context->buffer_index, op.bytes);        }    }    l=0;    if(context->buffer_index){        ogg_packet *op2= (ogg_packet*)context->buffer;        op2->packet = context->buffer + sizeof(ogg_packet);        l=  op2->bytes;        avccontext->coded_frame->pts= av_rescale_q(op2->granulepos, (AVRational){1, avccontext->sample_rate}, avccontext->time_base);        //FIXME we should reorder the user supplied pts and not assume that they are spaced by 1/sample_rate        memcpy(packets, op2->packet, l);        context->buffer_index -= l + sizeof(ogg_packet);        memcpy(context->buffer, context->buffer + l + sizeof(ogg_packet), context->buffer_index);//        av_log(avccontext, AV_LOG_DEBUG, "E%d\n", l);    }    return l;}static av_cold int oggvorbis_encode_close(AVCodecContext *avccontext) {    OggVorbisContext *context = avccontext->priv_data ;/*  ogg_packet op ; */    vorbis_analysis_wrote(&context->vd, 0) ; /* notify vorbisenc this is EOF */    vorbis_block_clear(&context->vb);    vorbis_dsp_clear(&context->vd);    vorbis_info_clear(&context->vi);    av_freep(&avccontext->coded_frame);    av_freep(&avccontext->extradata);    return 0 ;}AVCodec libvorbis_encoder = {    "libvorbis",    CODEC_TYPE_AUDIO,    CODEC_ID_VORBIS,    sizeof(OggVorbisContext),    oggvorbis_encode_init,    oggvorbis_encode_frame,    oggvorbis_encode_close,#ifdef __CW32__    0,    CODEC_CAP_DELAY,    0,    0,    0,    0,    NULL_IF_CONFIG_SMALL("libvorbis Vorbis"),#else    .capabilities= CODEC_CAP_DELAY,    .long_name= NULL_IF_CONFIG_SMALL("libvorbis Vorbis"),#endif} ;

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