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libavcodec/libvorbis.c

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00001 /*
00002  * copyright (c) 2002 Mark Hills <mark@pogo.org.uk>
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00027 #include <vorbis/vorbisenc.h>
00028 
00029 #include "libavutil/opt.h"
00030 #include "avcodec.h"
00031 #include "bytestream.h"
00032 #include "internal.h"
00033 #include "vorbis.h"
00034 #include "libavutil/mathematics.h"
00035 
00036 #undef NDEBUG
00037 #include <assert.h>
00038 
00039 #define OGGVORBIS_FRAME_SIZE 64
00040 
00041 #define BUFFER_SIZE (1024 * 64)
00042 
00043 typedef struct OggVorbisContext {
00044     AVClass *av_class;
00045     vorbis_info vi;
00046     vorbis_dsp_state vd;
00047     vorbis_block vb;
00048     uint8_t buffer[BUFFER_SIZE];
00049     int buffer_index;
00050     int eof;
00051 
00052     /* decoder */
00053     vorbis_comment vc;
00054     ogg_packet op;
00055 
00056     double iblock;
00057 } OggVorbisContext;
00058 
00059 static const AVOption options[] = {
00060     { "iblock", "Sets the impulse block bias", offsetof(OggVorbisContext, iblock), AV_OPT_TYPE_DOUBLE, { .dbl = 0 }, -15, 0, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
00061     { NULL }
00062 };
00063 
00064 static const AVCodecDefault defaults[] = {
00065     { "b",  "0" },
00066     { NULL },
00067 };
00068 
00069 static const AVClass class = { "libvorbis", av_default_item_name, options, LIBAVUTIL_VERSION_INT };
00070 
00071 static const char * error(int oggerr, int *averr)
00072 {
00073     switch (oggerr) {
00074         case OV_EFAULT: *averr = AVERROR(EFAULT); return "internal error";
00075         case OV_EIMPL:  *averr = AVERROR(EINVAL); return "not supported";
00076         case OV_EINVAL: *averr = AVERROR(EINVAL); return "invalid request";
00077         default:        *averr = AVERROR(EINVAL); return "unknown error";
00078     }
00079 }
00080 
00081 static av_cold int oggvorbis_init_encoder(vorbis_info *vi, AVCodecContext *avccontext)
00082 {
00083     OggVorbisContext *context = avccontext->priv_data;
00084     double cfreq;
00085 
00086     if (avccontext->flags & CODEC_FLAG_QSCALE || !avccontext->bit_rate) {
00087         /* variable bitrate
00088          * NOTE: we use the oggenc range of -1 to 10 for global_quality for
00089          *       user convenience, but libvorbis uses -0.1 to 1.0.
00090          */
00091         float q = avccontext->global_quality / (float)FF_QP2LAMBDA;
00092         /* default to 3 if the user did not set quality or bitrate */
00093         if (!(avccontext->flags & CODEC_FLAG_QSCALE))
00094             q = 3.0;
00095         if (vorbis_encode_setup_vbr(vi, avccontext->channels,
00096                                     avccontext->sample_rate,
00097                                     q / 10.0))
00098             return -1;
00099     } else {
00100         int minrate = avccontext->rc_min_rate > 0 ? avccontext->rc_min_rate : -1;
00101         int maxrate = avccontext->rc_max_rate > 0 ? avccontext->rc_max_rate : -1;
00102 
00103         /* constant bitrate */
00104         if (vorbis_encode_setup_managed(vi, avccontext->channels,
00105                                         avccontext->sample_rate, maxrate,
00106                                         avccontext->bit_rate, minrate))
00107             return -1;
00108 
00109         /* variable bitrate by estimate, disable slow rate management */
00110         if (minrate == -1 && maxrate == -1)
00111             if (vorbis_encode_ctl(vi, OV_ECTL_RATEMANAGE2_SET, NULL))
00112                 return AVERROR(EINVAL); /* should not happen */
00113     }
00114 
00115     /* cutoff frequency */
00116     if (avccontext->cutoff > 0) {
00117         cfreq = avccontext->cutoff / 1000.0;
00118         if (vorbis_encode_ctl(vi, OV_ECTL_LOWPASS_SET, &cfreq))
00119             return AVERROR(EINVAL); /* should not happen */
00120     }
00121 
00122     if (context->iblock) {
00123         vorbis_encode_ctl(vi, OV_ECTL_IBLOCK_SET, &context->iblock);
00124     }
00125 
00126     if (avccontext->channels == 3 &&
00127             avccontext->channel_layout != (AV_CH_LAYOUT_STEREO|AV_CH_FRONT_CENTER) ||
00128         avccontext->channels == 4 &&
00129             avccontext->channel_layout != AV_CH_LAYOUT_2_2 &&
00130             avccontext->channel_layout != AV_CH_LAYOUT_QUAD ||
00131         avccontext->channels == 5 &&
00132             avccontext->channel_layout != AV_CH_LAYOUT_5POINT0 &&
00133             avccontext->channel_layout != AV_CH_LAYOUT_5POINT0_BACK ||
00134         avccontext->channels == 6 &&
00135             avccontext->channel_layout != AV_CH_LAYOUT_5POINT1 &&
00136             avccontext->channel_layout != AV_CH_LAYOUT_5POINT1_BACK ||
00137         avccontext->channels == 7 &&
00138             avccontext->channel_layout != (AV_CH_LAYOUT_5POINT1|AV_CH_BACK_CENTER) ||
00139         avccontext->channels == 8 &&
00140             avccontext->channel_layout != AV_CH_LAYOUT_7POINT1) {
00141         if (avccontext->channel_layout) {
00142             char name[32];
00143             av_get_channel_layout_string(name, sizeof(name), avccontext->channels,
00144                                          avccontext->channel_layout);
00145             av_log(avccontext, AV_LOG_ERROR, "%s not supported by Vorbis: "
00146                                              "output stream will have incorrect "
00147                                              "channel layout.\n", name);
00148         } else {
00149             av_log(avccontext, AV_LOG_WARNING, "No channel layout specified. The encoder "
00150                                                "will use Vorbis channel layout for "
00151                                                "%d channels.\n", avccontext->channels);
00152         }
00153     }
00154 
00155     return vorbis_encode_setup_init(vi);
00156 }
00157 
00158 /* How many bytes are needed for a buffer of length 'l' */
00159 static int xiph_len(int l)
00160 {
00161     return 1 + l / 255 + l;
00162 }
00163 
00164 static av_cold int oggvorbis_encode_init(AVCodecContext *avccontext)
00165 {
00166     OggVorbisContext *context = avccontext->priv_data;
00167     ogg_packet header, header_comm, header_code;
00168     uint8_t *p;
00169     unsigned int offset;
00170     int r;
00171 
00172     vorbis_info_init(&context->vi);
00173     r = oggvorbis_init_encoder(&context->vi, avccontext);
00174     if (r < 0) {
00175         av_log(avccontext, AV_LOG_ERROR, "oggvorbis_encode_init failed\n");
00176         return r;
00177     }
00178     vorbis_analysis_init(&context->vd, &context->vi);
00179     vorbis_block_init(&context->vd, &context->vb);
00180 
00181     vorbis_comment_init(&context->vc);
00182     vorbis_comment_add_tag(&context->vc, "encoder", LIBAVCODEC_IDENT);
00183 
00184     vorbis_analysis_headerout(&context->vd, &context->vc, &header,
00185                               &header_comm, &header_code);
00186 
00187     avccontext->extradata_size =
00188         1 + xiph_len(header.bytes) + xiph_len(header_comm.bytes) +
00189         header_code.bytes;
00190     p = avccontext->extradata =
00191             av_malloc(avccontext->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
00192     p[0]    = 2;
00193     offset  = 1;
00194     offset += av_xiphlacing(&p[offset], header.bytes);
00195     offset += av_xiphlacing(&p[offset], header_comm.bytes);
00196     memcpy(&p[offset], header.packet, header.bytes);
00197     offset += header.bytes;
00198     memcpy(&p[offset], header_comm.packet, header_comm.bytes);
00199     offset += header_comm.bytes;
00200     memcpy(&p[offset], header_code.packet, header_code.bytes);
00201     offset += header_code.bytes;
00202     assert(offset == avccontext->extradata_size);
00203 
00204 #if 0
00205     vorbis_block_clear(&context->vb);
00206     vorbis_dsp_clear(&context->vd);
00207     vorbis_info_clear(&context->vi);
00208 #endif
00209     vorbis_comment_clear(&context->vc);
00210 
00211     avccontext->frame_size = OGGVORBIS_FRAME_SIZE;
00212 
00213     avccontext->coded_frame = avcodec_alloc_frame();
00214     avccontext->coded_frame->key_frame = 1;
00215 
00216     return 0;
00217 }
00218 
00219 static int oggvorbis_encode_frame(AVCodecContext *avccontext,
00220                                   unsigned char *packets,
00221                                   int buf_size, void *data)
00222 {
00223     OggVorbisContext *context = avccontext->priv_data;
00224     ogg_packet op;
00225     signed short *audio = data;
00226     int l;
00227 
00228     if (data) {
00229         const int samples = avccontext->frame_size;
00230         float **buffer;
00231         int c, channels = context->vi.channels;
00232 
00233         buffer = vorbis_analysis_buffer(&context->vd, samples);
00234         for (c = 0; c < channels; c++) {
00235             int co = (channels > 8) ? c :
00236                      ff_vorbis_encoding_channel_layout_offsets[channels - 1][c];
00237             for (l = 0; l < samples; l++)
00238                 buffer[c][l] = audio[l * channels + co] / 32768.f;
00239         }
00240         vorbis_analysis_wrote(&context->vd, samples);
00241     } else {
00242         if (!context->eof)
00243             vorbis_analysis_wrote(&context->vd, 0);
00244         context->eof = 1;
00245     }
00246 
00247     while (vorbis_analysis_blockout(&context->vd, &context->vb) == 1) {
00248         vorbis_analysis(&context->vb, NULL);
00249         vorbis_bitrate_addblock(&context->vb);
00250 
00251         while (vorbis_bitrate_flushpacket(&context->vd, &op)) {
00252             /* i'd love to say the following line is a hack, but sadly it's
00253              * not, apparently the end of stream decision is in libogg. */
00254             if (op.bytes == 1 && op.e_o_s)
00255                 continue;
00256             if (context->buffer_index + sizeof(ogg_packet) + op.bytes > BUFFER_SIZE) {
00257                 av_log(avccontext, AV_LOG_ERROR, "libvorbis: buffer overflow.\n");
00258                 return AVERROR(EINVAL);
00259             }
00260             memcpy(context->buffer + context->buffer_index, &op, sizeof(ogg_packet));
00261             context->buffer_index += sizeof(ogg_packet);
00262             memcpy(context->buffer + context->buffer_index, op.packet, op.bytes);
00263             context->buffer_index += op.bytes;
00264 //            av_log(avccontext, AV_LOG_DEBUG, "e%d / %d\n", context->buffer_index, op.bytes);
00265         }
00266     }
00267 
00268     l = 0;
00269     if (context->buffer_index) {
00270         ogg_packet *op2 = (ogg_packet *)context->buffer;
00271         op2->packet = context->buffer + sizeof(ogg_packet);
00272 
00273         l = op2->bytes;
00274         avccontext->coded_frame->pts = av_rescale_q(op2->granulepos, (AVRational) { 1, avccontext->sample_rate }, avccontext->time_base);
00275         //FIXME we should reorder the user supplied pts and not assume that they are spaced by 1/sample_rate
00276 
00277         if (l > buf_size) {
00278             av_log(avccontext, AV_LOG_ERROR, "libvorbis: buffer overflow.\n");
00279             return AVERROR(EINVAL);
00280         }
00281 
00282         memcpy(packets, op2->packet, l);
00283         context->buffer_index -= l + sizeof(ogg_packet);
00284         memmove(context->buffer, context->buffer + l + sizeof(ogg_packet), context->buffer_index);
00285 //        av_log(avccontext, AV_LOG_DEBUG, "E%d\n", l);
00286     }
00287 
00288     return l;
00289 }
00290 
00291 static av_cold int oggvorbis_encode_close(AVCodecContext *avccontext)
00292 {
00293     OggVorbisContext *context = avccontext->priv_data;
00294 /*  ogg_packet op ; */
00295 
00296     vorbis_analysis_wrote(&context->vd, 0);  /* notify vorbisenc this is EOF */
00297 
00298     vorbis_block_clear(&context->vb);
00299     vorbis_dsp_clear(&context->vd);
00300     vorbis_info_clear(&context->vi);
00301 
00302     av_freep(&avccontext->coded_frame);
00303     av_freep(&avccontext->extradata);
00304 
00305     return 0;
00306 }
00307 
00308 AVCodec ff_libvorbis_encoder = {
00309     .name           = "libvorbis",
00310     .type           = AVMEDIA_TYPE_AUDIO,
00311     .id             = CODEC_ID_VORBIS,
00312     .priv_data_size = sizeof(OggVorbisContext),
00313     .init           = oggvorbis_encode_init,
00314     .encode         = oggvorbis_encode_frame,
00315     .close          = oggvorbis_encode_close,
00316     .capabilities   = CODEC_CAP_DELAY,
00317     .sample_fmts    = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE },
00318     .long_name      = NULL_IF_CONFIG_SMALL("libvorbis Vorbis"),
00319     .priv_class     = &class,
00320     .defaults       = defaults,
00321 };
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