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libavformat/cafenc.c

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00001 /*
00002  * Core Audio Format muxer
00003  * Copyright (c) 2011 Carl Eugen Hoyos
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 "avformat.h"
00023 #include "caf.h"
00024 #include "riff.h"
00025 #include "isom.h"
00026 #include "avio_internal.h"
00027 #include "libavutil/intfloat.h"
00028 
00029 typedef struct {
00030     int64_t data;
00031     uint8_t *pkt_sizes;
00032     int size_buffer_size;
00033     int size_entries_used;
00034     int packets;
00035 } CAFContext;
00036 
00037 static uint32_t codec_flags(enum CodecID codec_id) {
00038     switch (codec_id) {
00039     case CODEC_ID_PCM_F32BE:
00040     case CODEC_ID_PCM_F64BE:
00041         return 1; //< kCAFLinearPCMFormatFlagIsFloat
00042     case CODEC_ID_PCM_S16LE:
00043     case CODEC_ID_PCM_S24LE:
00044     case CODEC_ID_PCM_S32LE:
00045         return 2; //< kCAFLinearPCMFormatFlagIsLittleEndian
00046     case CODEC_ID_PCM_F32LE:
00047     case CODEC_ID_PCM_F64LE:
00048         return 3; //< kCAFLinearPCMFormatFlagIsFloat | kCAFLinearPCMFormatFlagIsLittleEndian
00049     default:
00050         return 0;
00051     }
00052 }
00053 
00054 static uint32_t samples_per_packet(enum CodecID codec_id, int channels) {
00055     switch (codec_id) {
00056     case CODEC_ID_PCM_S8:
00057     case CODEC_ID_PCM_S16LE:
00058     case CODEC_ID_PCM_S16BE:
00059     case CODEC_ID_PCM_S24LE:
00060     case CODEC_ID_PCM_S24BE:
00061     case CODEC_ID_PCM_S32LE:
00062     case CODEC_ID_PCM_S32BE:
00063     case CODEC_ID_PCM_F32LE:
00064     case CODEC_ID_PCM_F32BE:
00065     case CODEC_ID_PCM_F64LE:
00066     case CODEC_ID_PCM_F64BE:
00067     case CODEC_ID_PCM_ALAW:
00068     case CODEC_ID_PCM_MULAW:
00069         return 1;
00070     case CODEC_ID_MACE3:
00071     case CODEC_ID_MACE6:
00072         return 6;
00073     case CODEC_ID_ADPCM_IMA_QT:
00074         return 64;
00075     case CODEC_ID_AMR_NB:
00076     case CODEC_ID_GSM:
00077     case CODEC_ID_QCELP:
00078         return 160;
00079     case CODEC_ID_GSM_MS:
00080         return 320;
00081     case CODEC_ID_MP1:
00082         return 384;
00083     case CODEC_ID_MP2:
00084     case CODEC_ID_MP3:
00085         return 1152;
00086     case CODEC_ID_AC3:
00087         return 1536;
00088     case CODEC_ID_ALAC:
00089     case CODEC_ID_QDM2:
00090         return 4096;
00091     case CODEC_ID_ADPCM_IMA_WAV:
00092         return (1024 - 4 * channels) * 8 / (4 * channels) + 1;
00093     case CODEC_ID_ADPCM_MS:
00094         return (1024 - 7 * channels) * 2 / channels + 2;
00095     default:
00096         return 0;
00097     }
00098 }
00099 
00100 static int caf_write_header(AVFormatContext *s)
00101 {
00102     AVIOContext *pb = s->pb;
00103     AVCodecContext *enc = s->streams[0]->codec;
00104     CAFContext *caf = s->priv_data;
00105     unsigned int codec_tag = ff_codec_get_tag(ff_codec_caf_tags, enc->codec_id);
00106 
00107     switch (enc->codec_id) {
00108     case CODEC_ID_AAC:
00109     case CODEC_ID_AC3:
00110         av_log(s, AV_LOG_ERROR, "muxing codec currently unsupported\n");
00111         return AVERROR_PATCHWELCOME;
00112     }
00113 
00114     switch (enc->codec_id) {
00115     case CODEC_ID_PCM_S8:
00116     case CODEC_ID_PCM_S16LE:
00117     case CODEC_ID_PCM_S16BE:
00118     case CODEC_ID_PCM_S24LE:
00119     case CODEC_ID_PCM_S24BE:
00120     case CODEC_ID_PCM_S32LE:
00121     case CODEC_ID_PCM_S32BE:
00122     case CODEC_ID_PCM_F32LE:
00123     case CODEC_ID_PCM_F32BE:
00124     case CODEC_ID_PCM_F64LE:
00125     case CODEC_ID_PCM_F64BE:
00126     case CODEC_ID_PCM_ALAW:
00127     case CODEC_ID_PCM_MULAW:
00128         codec_tag = MKTAG('l','p','c','m');
00129     }
00130 
00131     if (!codec_tag) {
00132         av_log(s, AV_LOG_ERROR, "unsupported codec\n");
00133         return AVERROR_INVALIDDATA;
00134     }
00135 
00136     if (!enc->block_align && !pb->seekable) {
00137         av_log(s, AV_LOG_ERROR, "Muxing variable packet size not supported on non seekable output\n");
00138         return AVERROR_INVALIDDATA;
00139     }
00140 
00141     ffio_wfourcc(pb, "caff"); //< mFileType
00142     avio_wb16(pb, 1);         //< mFileVersion
00143     avio_wb16(pb, 0);         //< mFileFlags
00144 
00145     ffio_wfourcc(pb, "desc");                         //< Audio Description chunk
00146     avio_wb64(pb, 32);                                //< mChunkSize
00147     avio_wb64(pb, av_double2int(enc->sample_rate));   //< mSampleRate
00148     avio_wl32(pb, codec_tag);                         //< mFormatID
00149     avio_wb32(pb, codec_flags(enc->codec_id));        //< mFormatFlags
00150     avio_wb32(pb, enc->block_align);                  //< mBytesPerPacket
00151     avio_wb32(pb, samples_per_packet(enc->codec_id, enc->channels)); //< mFramesPerPacket
00152     avio_wb32(pb, enc->channels);                     //< mChannelsPerFrame
00153     avio_wb32(pb, av_get_bits_per_sample(enc->codec_id)); //< mBitsPerChannel
00154 
00155     if (enc->channel_layout) {
00156         ffio_wfourcc(pb, "chan");
00157         avio_wb64(pb, 12);
00158         ff_mov_write_chan(pb, enc->channel_layout);
00159     }
00160 
00161     if (enc->codec_id == CODEC_ID_ALAC) {
00162         ffio_wfourcc(pb, "kuki");
00163         avio_wb64(pb, 12 + enc->extradata_size);
00164         avio_write(pb, "\0\0\0\14frmaalac", 12);
00165         avio_write(pb, enc->extradata, enc->extradata_size);
00166     } else if (enc->codec_id == CODEC_ID_AMR_NB) {
00167         ffio_wfourcc(pb, "kuki");
00168         avio_wb64(pb, 29);
00169         avio_write(pb, "\0\0\0\14frmasamr", 12);
00170         avio_wb32(pb, 0x11); /* size */
00171         avio_write(pb, "samrFFMP", 8);
00172         avio_w8(pb, 0); /* decoder version */
00173 
00174         avio_wb16(pb, 0x81FF); /* Mode set (all modes for AMR_NB) */
00175         avio_w8(pb, 0x00); /* Mode change period (no restriction) */
00176         avio_w8(pb, 0x01); /* Frames per sample */
00177     } else if (enc->codec_id == CODEC_ID_QDM2) {
00178         ffio_wfourcc(pb, "kuki");
00179         avio_wb64(pb, enc->extradata_size);
00180         avio_write(pb, enc->extradata, enc->extradata_size);
00181     }
00182 
00183     ffio_wfourcc(pb, "data"); //< Audio Data chunk
00184     caf->data = avio_tell(pb);
00185     avio_wb64(pb, -1);        //< mChunkSize
00186     avio_wb32(pb, 0);         //< mEditCount
00187 
00188     avio_flush(pb);
00189     return 0;
00190 }
00191 
00192 static int caf_write_packet(AVFormatContext *s, AVPacket *pkt)
00193 {
00194     CAFContext *caf = s->priv_data;
00195 
00196     avio_write(s->pb, pkt->data, pkt->size);
00197     if (!s->streams[0]->codec->block_align) {
00198         void *pkt_sizes = caf->pkt_sizes;
00199         int i, alloc_size = caf->size_entries_used + 5;
00200         if (alloc_size < 0) {
00201             caf->pkt_sizes = NULL;
00202         } else {
00203             caf->pkt_sizes = av_fast_realloc(caf->pkt_sizes,
00204                                              &caf->size_buffer_size,
00205                                              alloc_size);
00206         }
00207         if (!caf->pkt_sizes) {
00208             av_free(pkt_sizes);
00209             return AVERROR(ENOMEM);
00210         }
00211         for (i = 4; i > 0; i--) {
00212             unsigned top = pkt->size >> i * 7;
00213             if (top)
00214                 caf->pkt_sizes[caf->size_entries_used++] = 128 | top;
00215         }
00216         caf->pkt_sizes[caf->size_entries_used++] = pkt->size & 127;
00217         caf->packets++;
00218     }
00219     return 0;
00220 }
00221 
00222 static int caf_write_trailer(AVFormatContext *s)
00223 {
00224     AVIOContext *pb = s->pb;
00225     AVCodecContext *enc = s->streams[0]->codec;
00226 
00227     if (pb->seekable) {
00228         CAFContext *caf = s->priv_data;
00229         int64_t file_size = avio_tell(pb);
00230 
00231         avio_seek(pb, caf->data, SEEK_SET);
00232         avio_wb64(pb, file_size - caf->data - 8);
00233         avio_seek(pb, file_size, SEEK_SET);
00234         if (!enc->block_align) {
00235             ffio_wfourcc(pb, "pakt");
00236             avio_wb64(pb, caf->size_entries_used + 24);
00237             avio_wb64(pb, caf->packets); 
00238             avio_wb64(pb, caf->packets * samples_per_packet(enc->codec_id, enc->channels)); 
00239             avio_wb32(pb, 0); 
00240             avio_wb32(pb, 0); 
00241             avio_write(pb, caf->pkt_sizes, caf->size_entries_used);
00242             av_freep(&caf->pkt_sizes);
00243             caf->size_buffer_size = 0;
00244         }
00245         avio_flush(pb);
00246     }
00247     return 0;
00248 }
00249 
00250 AVOutputFormat ff_caf_muxer = {
00251     .name           = "caf",
00252     .long_name      = NULL_IF_CONFIG_SMALL("Apple Core Audio Format"),
00253     .mime_type      = "audio/x-caf",
00254     .extensions     = "caf",
00255     .priv_data_size = sizeof(CAFContext),
00256     .audio_codec    = CODEC_ID_PCM_S16BE,
00257     .video_codec    = CODEC_ID_NONE,
00258     .write_header   = caf_write_header,
00259     .write_packet   = caf_write_packet,
00260     .write_trailer  = caf_write_trailer,
00261     .codec_tag= (const AVCodecTag* const []){ff_codec_caf_tags, 0},
00262 };
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