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

libavformat/aiff.c

Go to the documentation of this file.
00001 /*
00002  * AIFF/AIFF-C muxer and demuxer
00003  * Copyright (c) 2006  Patrick Guimond
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 "libavutil/intfloat_readwrite.h"
00023 #include "avformat.h"
00024 #include "raw.h"
00025 #include "riff.h"
00026 
00027 static const AVCodecTag codec_aiff_tags[] = {
00028     { CODEC_ID_PCM_S16BE,    MKTAG('N','O','N','E') },
00029     { CODEC_ID_PCM_S8,       MKTAG('N','O','N','E') },
00030     { CODEC_ID_PCM_S24BE,    MKTAG('N','O','N','E') },
00031     { CODEC_ID_PCM_S32BE,    MKTAG('N','O','N','E') },
00032     { CODEC_ID_PCM_F32BE,    MKTAG('f','l','3','2') },
00033     { CODEC_ID_PCM_F64BE,    MKTAG('f','l','6','4') },
00034     { CODEC_ID_PCM_ALAW,     MKTAG('a','l','a','w') },
00035     { CODEC_ID_PCM_MULAW,    MKTAG('u','l','a','w') },
00036     { CODEC_ID_MACE3,        MKTAG('M','A','C','3') },
00037     { CODEC_ID_MACE6,        MKTAG('M','A','C','6') },
00038     { CODEC_ID_GSM,          MKTAG('G','S','M',' ') },
00039     { CODEC_ID_ADPCM_G726,   MKTAG('G','7','2','6') },
00040     { CODEC_ID_PCM_S16LE,    MKTAG('s','o','w','t') },
00041     { CODEC_ID_ADPCM_IMA_QT, MKTAG('i','m','a','4') },
00042     { CODEC_ID_QDM2,         MKTAG('Q','D','M','2') },
00043     { 0, 0 },
00044 };
00045 
00046 #define AIFF                    0
00047 #define AIFF_C_VERSION1         0xA2805140
00048 
00049 static enum CodecID aiff_codec_get_id(int bps)
00050 {
00051     if (bps <= 8)
00052         return CODEC_ID_PCM_S8;
00053     if (bps <= 16)
00054         return CODEC_ID_PCM_S16BE;
00055     if (bps <= 24)
00056         return CODEC_ID_PCM_S24BE;
00057     if (bps <= 32)
00058         return CODEC_ID_PCM_S32BE;
00059 
00060     /* bigger than 32 isn't allowed  */
00061     return CODEC_ID_NONE;
00062 }
00063 
00064 /* returns the size of the found tag */
00065 static int get_tag(ByteIOContext *pb, uint32_t * tag)
00066 {
00067     int size;
00068 
00069     if (url_feof(pb))
00070         return AVERROR(EIO);
00071 
00072     *tag = get_le32(pb);
00073     size = get_be32(pb);
00074 
00075     if (size < 0)
00076         size = 0x7fffffff;
00077 
00078     return size;
00079 }
00080 
00081 /* Metadata string read */
00082 static void get_meta(AVFormatContext *s, const char *key, int size)
00083 {
00084     uint8_t str[1024];
00085     int res = get_buffer(s->pb, str, FFMIN(sizeof(str)-1, size));
00086     if (res < 0)
00087         return;
00088 
00089     str[res] = 0;
00090     if (size & 1)
00091         size++;
00092     size -= res;
00093     if (size)
00094         url_fskip(s->pb, size);
00095 
00096     av_metadata_set(&s->metadata, key, str);
00097 }
00098 
00099 /* Returns the number of sound data frames or negative on error */
00100 static unsigned int get_aiff_header(ByteIOContext *pb, AVCodecContext *codec,
00101                              int size, unsigned version)
00102 {
00103     AVExtFloat ext;
00104     double sample_rate;
00105     unsigned int num_frames;
00106 
00107     if (size & 1)
00108         size++;
00109     codec->codec_type = CODEC_TYPE_AUDIO;
00110     codec->channels = get_be16(pb);
00111     num_frames = get_be32(pb);
00112     codec->bits_per_coded_sample = get_be16(pb);
00113 
00114     get_buffer(pb, (uint8_t*)&ext, sizeof(ext));/* Sample rate is in */
00115     sample_rate = av_ext2dbl(ext);          /* 80 bits BE IEEE extended float */
00116     codec->sample_rate = sample_rate;
00117     size -= 18;
00118 
00119     /* Got an AIFF-C? */
00120     if (version == AIFF_C_VERSION1) {
00121         codec->codec_tag = get_le32(pb);
00122         codec->codec_id  = codec_get_id(codec_aiff_tags, codec->codec_tag);
00123 
00124         switch (codec->codec_id) {
00125         case CODEC_ID_PCM_S16BE:
00126             codec->codec_id = aiff_codec_get_id(codec->bits_per_coded_sample);
00127             codec->bits_per_coded_sample = av_get_bits_per_sample(codec->codec_id);
00128             break;
00129         case CODEC_ID_ADPCM_IMA_QT:
00130             codec->block_align = 34*codec->channels;
00131             codec->frame_size = 64;
00132             break;
00133         case CODEC_ID_MACE3:
00134             codec->block_align = 2*codec->channels;
00135             codec->frame_size = 6;
00136             break;
00137         case CODEC_ID_MACE6:
00138             codec->block_align = 1*codec->channels;
00139             codec->frame_size = 6;
00140             break;
00141         case CODEC_ID_GSM:
00142             codec->block_align = 33;
00143             codec->frame_size = 160;
00144             break;
00145         default:
00146             break;
00147         }
00148         size -= 4;
00149     } else {
00150         /* Need the codec type */
00151         codec->codec_id = aiff_codec_get_id(codec->bits_per_coded_sample);
00152         codec->bits_per_coded_sample = av_get_bits_per_sample(codec->codec_id);
00153     }
00154 
00155     /* Block align needs to be computed in all cases, as the definition
00156      * is specific to applications -> here we use the WAVE format definition */
00157     if (!codec->block_align)
00158         codec->block_align = (codec->bits_per_coded_sample * codec->channels) >> 3;
00159 
00160     codec->bit_rate = (codec->frame_size ? codec->sample_rate/codec->frame_size :
00161                        codec->sample_rate) * (codec->block_align << 3);
00162 
00163     /* Chunk is over */
00164     if (size)
00165         url_fseek(pb, size, SEEK_CUR);
00166 
00167     return num_frames;
00168 }
00169 
00170 #if CONFIG_AIFF_MUXER
00171 typedef struct {
00172     int64_t form;
00173     int64_t frames;
00174     int64_t ssnd;
00175 } AIFFOutputContext;
00176 
00177 static int aiff_write_header(AVFormatContext *s)
00178 {
00179     AIFFOutputContext *aiff = s->priv_data;
00180     ByteIOContext *pb = s->pb;
00181     AVCodecContext *enc = s->streams[0]->codec;
00182     AVExtFloat sample_rate;
00183     int aifc = 0;
00184 
00185     /* First verify if format is ok */
00186     if (!enc->codec_tag)
00187         return -1;
00188     if (enc->codec_tag != MKTAG('N','O','N','E'))
00189         aifc = 1;
00190 
00191     /* FORM AIFF header */
00192     put_tag(pb, "FORM");
00193     aiff->form = url_ftell(pb);
00194     put_be32(pb, 0);                    /* file length */
00195     put_tag(pb, aifc ? "AIFC" : "AIFF");
00196 
00197     if (aifc) { // compressed audio
00198         enc->bits_per_coded_sample = 16;
00199         if (!enc->block_align) {
00200             av_log(s, AV_LOG_ERROR, "block align not set\n");
00201             return -1;
00202         }
00203         /* Version chunk */
00204         put_tag(pb, "FVER");
00205         put_be32(pb, 4);
00206         put_be32(pb, 0xA2805140);
00207     }
00208 
00209     /* Common chunk */
00210     put_tag(pb, "COMM");
00211     put_be32(pb, aifc ? 24 : 18); /* size */
00212     put_be16(pb, enc->channels);  /* Number of channels */
00213 
00214     aiff->frames = url_ftell(pb);
00215     put_be32(pb, 0);              /* Number of frames */
00216 
00217     if (!enc->bits_per_coded_sample)
00218         enc->bits_per_coded_sample = av_get_bits_per_sample(enc->codec_id);
00219     if (!enc->bits_per_coded_sample) {
00220         av_log(s, AV_LOG_ERROR, "could not compute bits per sample\n");
00221         return -1;
00222     }
00223     if (!enc->block_align)
00224         enc->block_align = (enc->bits_per_coded_sample * enc->channels) >> 3;
00225 
00226     put_be16(pb, enc->bits_per_coded_sample); /* Sample size */
00227 
00228     sample_rate = av_dbl2ext((double)enc->sample_rate);
00229     put_buffer(pb, (uint8_t*)&sample_rate, sizeof(sample_rate));
00230 
00231     if (aifc) {
00232         put_le32(pb, enc->codec_tag);
00233         put_be16(pb, 0);
00234     }
00235 
00236     /* Sound data chunk */
00237     put_tag(pb, "SSND");
00238     aiff->ssnd = url_ftell(pb);         /* Sound chunk size */
00239     put_be32(pb, 0);                    /* Sound samples data size */
00240     put_be32(pb, 0);                    /* Data offset */
00241     put_be32(pb, 0);                    /* Block-size (block align) */
00242 
00243     av_set_pts_info(s->streams[0], 64, 1, s->streams[0]->codec->sample_rate);
00244 
00245     /* Data is starting here */
00246     put_flush_packet(pb);
00247 
00248     return 0;
00249 }
00250 
00251 static int aiff_write_packet(AVFormatContext *s, AVPacket *pkt)
00252 {
00253     ByteIOContext *pb = s->pb;
00254     put_buffer(pb, pkt->data, pkt->size);
00255     return 0;
00256 }
00257 
00258 static int aiff_write_trailer(AVFormatContext *s)
00259 {
00260     ByteIOContext *pb = s->pb;
00261     AIFFOutputContext *aiff = s->priv_data;
00262     AVCodecContext *enc = s->streams[0]->codec;
00263 
00264     /* Chunks sizes must be even */
00265     int64_t file_size, end_size;
00266     end_size = file_size = url_ftell(pb);
00267     if (file_size & 1) {
00268         put_byte(pb, 0);
00269         end_size++;
00270     }
00271 
00272     if (!url_is_streamed(s->pb)) {
00273         /* File length */
00274         url_fseek(pb, aiff->form, SEEK_SET);
00275         put_be32(pb, file_size - aiff->form - 4);
00276 
00277         /* Number of sample frames */
00278         url_fseek(pb, aiff->frames, SEEK_SET);
00279         put_be32(pb, (file_size-aiff->ssnd-12)/enc->block_align);
00280 
00281         /* Sound Data chunk size */
00282         url_fseek(pb, aiff->ssnd, SEEK_SET);
00283         put_be32(pb, file_size - aiff->ssnd - 4);
00284 
00285         /* return to the end */
00286         url_fseek(pb, end_size, SEEK_SET);
00287 
00288         put_flush_packet(pb);
00289     }
00290 
00291     return 0;
00292 }
00293 #endif /* CONFIG_AIFF_MUXER */
00294 
00295 static int aiff_probe(AVProbeData *p)
00296 {
00297     /* check file header */
00298     if (p->buf[0] == 'F' && p->buf[1] == 'O' &&
00299         p->buf[2] == 'R' && p->buf[3] == 'M' &&
00300         p->buf[8] == 'A' && p->buf[9] == 'I' &&
00301         p->buf[10] == 'F' && (p->buf[11] == 'F' || p->buf[11] == 'C'))
00302         return AVPROBE_SCORE_MAX;
00303     else
00304         return 0;
00305 }
00306 
00307 /* aiff input */
00308 static int aiff_read_header(AVFormatContext *s,
00309                             AVFormatParameters *ap)
00310 {
00311     int size, filesize;
00312     int64_t offset = 0;
00313     uint32_t tag;
00314     unsigned version = AIFF_C_VERSION1;
00315     ByteIOContext *pb = s->pb;
00316     AVStream * st = s->streams[0];
00317 
00318     /* check FORM header */
00319     filesize = get_tag(pb, &tag);
00320     if (filesize < 0 || tag != MKTAG('F', 'O', 'R', 'M'))
00321         return AVERROR_INVALIDDATA;
00322 
00323     /* AIFF data type */
00324     tag = get_le32(pb);
00325     if (tag == MKTAG('A', 'I', 'F', 'F'))       /* Got an AIFF file */
00326         version = AIFF;
00327     else if (tag != MKTAG('A', 'I', 'F', 'C'))  /* An AIFF-C file then */
00328         return AVERROR_INVALIDDATA;
00329 
00330     filesize -= 4;
00331 
00332     st = av_new_stream(s, 0);
00333     if (!st)
00334         return AVERROR(ENOMEM);
00335 
00336     while (filesize > 0) {
00337         /* parse different chunks */
00338         size = get_tag(pb, &tag);
00339         if (size < 0)
00340             return size;
00341 
00342         filesize -= size + 8;
00343 
00344         switch (tag) {
00345         case MKTAG('C', 'O', 'M', 'M'):     /* Common chunk */
00346             /* Then for the complete header info */
00347             st->nb_frames = get_aiff_header(pb, st->codec, size, version);
00348             if (st->nb_frames < 0)
00349                 return st->nb_frames;
00350             if (offset > 0) // COMM is after SSND
00351                 goto got_sound;
00352             break;
00353         case MKTAG('F', 'V', 'E', 'R'):     /* Version chunk */
00354             version = get_be32(pb);
00355             break;
00356         case MKTAG('N', 'A', 'M', 'E'):     /* Sample name chunk */
00357             get_meta(s, "title"    , size);
00358             break;
00359         case MKTAG('A', 'U', 'T', 'H'):     /* Author chunk */
00360             get_meta(s, "author"   , size);
00361             break;
00362         case MKTAG('(', 'c', ')', ' '):     /* Copyright chunk */
00363             get_meta(s, "copyright", size);
00364             break;
00365         case MKTAG('A', 'N', 'N', 'O'):     /* Annotation chunk */
00366             get_meta(s, "comment"  , size);
00367             break;
00368         case MKTAG('S', 'S', 'N', 'D'):     /* Sampled sound chunk */
00369             offset = get_be32(pb);      /* Offset of sound data */
00370             get_be32(pb);               /* BlockSize... don't care */
00371             offset += url_ftell(pb);    /* Compute absolute data offset */
00372             if (st->codec->block_align)    /* Assume COMM already parsed */
00373                 goto got_sound;
00374             if (url_is_streamed(pb)) {
00375                 av_log(s, AV_LOG_ERROR, "file is not seekable\n");
00376                 return -1;
00377             }
00378             url_fskip(pb, size - 8);
00379             break;
00380         case MKTAG('w', 'a', 'v', 'e'):
00381             if ((uint64_t)size > (1<<30))
00382                 return -1;
00383             st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE);
00384             if (!st->codec->extradata)
00385                 return AVERROR(ENOMEM);
00386             st->codec->extradata_size = size;
00387             get_buffer(pb, st->codec->extradata, size);
00388             break;
00389         default: /* Jump */
00390             if (size & 1)   /* Always even aligned */
00391                 size++;
00392             url_fskip (pb, size);
00393         }
00394     }
00395 
00396     if (!st->codec->block_align) {
00397         av_log(s, AV_LOG_ERROR, "could not find COMM tag\n");
00398         return -1;
00399     }
00400 
00401 got_sound:
00402     /* Now positioned, get the sound data start and end */
00403     if (st->nb_frames)
00404         s->file_size = st->nb_frames * st->codec->block_align;
00405 
00406     av_set_pts_info(st, 64, 1, st->codec->sample_rate);
00407     st->start_time = 0;
00408     st->duration = st->codec->frame_size ?
00409         st->nb_frames * st->codec->frame_size : st->nb_frames;
00410 
00411     /* Position the stream at the first block */
00412     url_fseek(pb, offset, SEEK_SET);
00413 
00414     return 0;
00415 }
00416 
00417 #define MAX_SIZE 4096
00418 
00419 static int aiff_read_packet(AVFormatContext *s,
00420                             AVPacket *pkt)
00421 {
00422     AVStream *st = s->streams[0];
00423     int res;
00424 
00425     /* End of stream may be reached */
00426     if (url_feof(s->pb))
00427         return AVERROR(EIO);
00428 
00429     /* Now for that packet */
00430     res = av_get_packet(s->pb, pkt, (MAX_SIZE / st->codec->block_align) * st->codec->block_align);
00431     if (res < 0)
00432         return res;
00433 
00434     /* Only one stream in an AIFF file */
00435     pkt->stream_index = 0;
00436     return 0;
00437 }
00438 
00439 #if CONFIG_AIFF_DEMUXER
00440 AVInputFormat aiff_demuxer = {
00441     "aiff",
00442     NULL_IF_CONFIG_SMALL("Audio IFF"),
00443     0,
00444     aiff_probe,
00445     aiff_read_header,
00446     aiff_read_packet,
00447     NULL,
00448     pcm_read_seek,
00449     .codec_tag= (const AVCodecTag* const []){codec_aiff_tags, 0},
00450 };
00451 #endif
00452 
00453 #if CONFIG_AIFF_MUXER
00454 AVOutputFormat aiff_muxer = {
00455     "aiff",
00456     NULL_IF_CONFIG_SMALL("Audio IFF"),
00457     "audio/aiff",
00458     "aif,aiff,afc,aifc",
00459     sizeof(AIFFOutputContext),
00460     CODEC_ID_PCM_S16BE,
00461     CODEC_ID_NONE,
00462     aiff_write_header,
00463     aiff_write_packet,
00464     aiff_write_trailer,
00465     .codec_tag= (const AVCodecTag* const []){codec_aiff_tags, 0},
00466 };
00467 #endif

Generated on Sat Feb 16 2013 09:23:14 for ffmpeg by  doxygen 1.7.1