FFmpeg: libavformat/aiffdec.c Source File

00001 /*
00002  * AIFF/AIFF-C 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/intreadwrite.h"
00023 #include "libavutil/mathematics.h"
00024 #include "libavutil/dict.h"
00025 #include "avformat.h"
00026 #include "internal.h"
00027 #include "pcm.h"
00028 #include "aiff.h"
00029 #include "isom.h"
00030 #include "id3v2.h"
00031 
00032 #define AIFF                    0
00033 #define AIFF_C_VERSION1         0xA2805140
00034 
00035 typedef struct {
00036     int64_t data_end;
00037     int block_duration;
00038 } AIFFInputContext;
00039 
00040 static enum AVCodecID aiff_codec_get_id(int bps)
00041 {
00042     if (bps <= 8)
00043         return AV_CODEC_ID_PCM_S8;
00044     if (bps <= 16)
00045         return AV_CODEC_ID_PCM_S16BE;
00046     if (bps <= 24)
00047         return AV_CODEC_ID_PCM_S24BE;
00048     if (bps <= 32)
00049         return AV_CODEC_ID_PCM_S32BE;
00050 
00051     /* bigger than 32 isn't allowed  */
00052     return AV_CODEC_ID_NONE;
00053 }
00054 
00055 /* returns the size of the found tag */
00056 static int get_tag(AVIOContext *pb, uint32_t * tag)
00057 {
00058     int size;
00059 
00060     if (url_feof(pb))
00061         return AVERROR(EIO);
00062 
00063     *tag = avio_rl32(pb);
00064     size = avio_rb32(pb);
00065 
00066     if (size < 0)
00067         size = 0x7fffffff;
00068 
00069     return size;
00070 }
00071 
00072 /* Metadata string read */
00073 static void get_meta(AVFormatContext *s, const char *key, int size)
00074 {
00075     uint8_t *str = av_malloc(size+1);
00076 
00077     if (str) {
00078         int res = avio_read(s->pb, str, size);
00079         if (res < 0){
00080             av_free(str);
00081             return;
00082         }
00083         size += (size&1)-res;
00084         str[res] = 0;
00085         av_dict_set(&s->metadata, key, str, AV_DICT_DONT_STRDUP_VAL);
00086     }else
00087         size+= size&1;
00088 
00089     avio_skip(s->pb, size);
00090 }
00091 
00092 /* Returns the number of sound data frames or negative on error */
00093 static unsigned int get_aiff_header(AVFormatContext *s, int size,
00094                                     unsigned version)
00095 {
00096     AVIOContext *pb        = s->pb;
00097     AVCodecContext *codec  = s->streams[0]->codec;
00098     AIFFInputContext *aiff = s->priv_data;
00099     int exp;
00100     uint64_t val;
00101     double sample_rate;
00102     unsigned int num_frames;
00103 
00104     if (size & 1)
00105         size++;
00106     codec->codec_type = AVMEDIA_TYPE_AUDIO;
00107     codec->channels = avio_rb16(pb);
00108     num_frames = avio_rb32(pb);
00109     codec->bits_per_coded_sample = avio_rb16(pb);
00110 
00111     exp = avio_rb16(pb);
00112     val = avio_rb64(pb);
00113     sample_rate = ldexp(val, exp - 16383 - 63);
00114     codec->sample_rate = sample_rate;
00115     size -= 18;
00116 
00117     /* get codec id for AIFF-C */
00118     if (version == AIFF_C_VERSION1) {
00119         codec->codec_tag = avio_rl32(pb);
00120         codec->codec_id  = ff_codec_get_id(ff_codec_aiff_tags, codec->codec_tag);
00121         size -= 4;
00122     }
00123 
00124     if (version != AIFF_C_VERSION1 || codec->codec_id == AV_CODEC_ID_PCM_S16BE) {
00125         codec->codec_id = aiff_codec_get_id(codec->bits_per_coded_sample);
00126         codec->bits_per_coded_sample = av_get_bits_per_sample(codec->codec_id);
00127         aiff->block_duration = 1;
00128     } else {
00129         switch (codec->codec_id) {
00130         case AV_CODEC_ID_PCM_F32BE:
00131         case AV_CODEC_ID_PCM_F64BE:
00132         case AV_CODEC_ID_PCM_S16LE:
00133         case AV_CODEC_ID_PCM_ALAW:
00134         case AV_CODEC_ID_PCM_MULAW:
00135             aiff->block_duration = 1;
00136             break;
00137         case AV_CODEC_ID_ADPCM_IMA_QT:
00138             codec->block_align = 34*codec->channels;
00139             break;
00140         case AV_CODEC_ID_MACE3:
00141             codec->block_align = 2*codec->channels;
00142             break;
00143         case AV_CODEC_ID_MACE6:
00144             codec->block_align = 1*codec->channels;
00145             break;
00146         case AV_CODEC_ID_GSM:
00147             codec->block_align = 33;
00148             break;
00149         case AV_CODEC_ID_QCELP:
00150             codec->block_align = 35;
00151             break;
00152         default:
00153             aiff->block_duration = 1;
00154             break;
00155         }
00156         if (codec->block_align > 0)
00157             aiff->block_duration = av_get_audio_frame_duration(codec,
00158                                                                codec->block_align);
00159     }
00160 
00161     /* Block align needs to be computed in all cases, as the definition
00162      * is specific to applications -> here we use the WAVE format definition */
00163     if (!codec->block_align)
00164         codec->block_align = (av_get_bits_per_sample(codec->codec_id) * codec->channels) >> 3;
00165 
00166     if (aiff->block_duration) {
00167         codec->bit_rate = codec->sample_rate * (codec->block_align << 3) /
00168                           aiff->block_duration;
00169     }
00170 
00171     /* Chunk is over */
00172     if (size)
00173         avio_skip(pb, size);
00174 
00175     return num_frames;
00176 }
00177 
00178 static int aiff_probe(AVProbeData *p)
00179 {
00180     /* check file header */
00181     if (p->buf[0] == 'F' && p->buf[1] == 'O' &&
00182         p->buf[2] == 'R' && p->buf[3] == 'M' &&
00183         p->buf[8] == 'A' && p->buf[9] == 'I' &&
00184         p->buf[10] == 'F' && (p->buf[11] == 'F' || p->buf[11] == 'C'))
00185         return AVPROBE_SCORE_MAX;
00186     else
00187         return 0;
00188 }
00189 
00190 /* aiff input */
00191 static int aiff_read_header(AVFormatContext *s)
00192 {
00193     int size, filesize;
00194     int64_t offset = 0;
00195     uint32_t tag;
00196     unsigned version = AIFF_C_VERSION1;
00197     AVIOContext *pb = s->pb;
00198     AVStream * st;
00199     AIFFInputContext *aiff = s->priv_data;
00200     ID3v2ExtraMeta *id3v2_extra_meta = NULL;
00201 
00202     /* check FORM header */
00203     filesize = get_tag(pb, &tag);
00204     if (filesize < 0 || tag != MKTAG('F', 'O', 'R', 'M'))
00205         return AVERROR_INVALIDDATA;
00206 
00207     /* AIFF data type */
00208     tag = avio_rl32(pb);
00209     if (tag == MKTAG('A', 'I', 'F', 'F'))       /* Got an AIFF file */
00210         version = AIFF;
00211     else if (tag != MKTAG('A', 'I', 'F', 'C'))  /* An AIFF-C file then */
00212         return AVERROR_INVALIDDATA;
00213 
00214     filesize -= 4;
00215 
00216     st = avformat_new_stream(s, NULL);
00217     if (!st)
00218         return AVERROR(ENOMEM);
00219 
00220     while (filesize > 0) {
00221         /* parse different chunks */
00222         size = get_tag(pb, &tag);
00223         if (size < 0)
00224             return size;
00225 
00226         filesize -= size + 8;
00227 
00228         switch (tag) {
00229         case MKTAG('C', 'O', 'M', 'M'):     /* Common chunk */
00230             /* Then for the complete header info */
00231             st->nb_frames = get_aiff_header(s, size, version);
00232             if (st->nb_frames < 0)
00233                 return st->nb_frames;
00234             if (offset > 0) // COMM is after SSND
00235                 goto got_sound;
00236             break;
00237         case MKTAG('I', 'D', '3', ' '):
00238             ff_id3v2_read(s, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta);
00239             ff_id3v2_free_extra_meta(&id3v2_extra_meta);
00240             break;
00241         case MKTAG('F', 'V', 'E', 'R'):     /* Version chunk */
00242             version = avio_rb32(pb);
00243             break;
00244         case MKTAG('N', 'A', 'M', 'E'):     /* Sample name chunk */
00245             get_meta(s, "title"    , size);
00246             break;
00247         case MKTAG('A', 'U', 'T', 'H'):     /* Author chunk */
00248             get_meta(s, "author"   , size);
00249             break;
00250         case MKTAG('(', 'c', ')', ' '):     /* Copyright chunk */
00251             get_meta(s, "copyright", size);
00252             break;
00253         case MKTAG('A', 'N', 'N', 'O'):     /* Annotation chunk */
00254             get_meta(s, "comment"  , size);
00255             break;
00256         case MKTAG('S', 'S', 'N', 'D'):     /* Sampled sound chunk */
00257             aiff->data_end = avio_tell(pb) + size;
00258             offset = avio_rb32(pb);      /* Offset of sound data */
00259             avio_rb32(pb);               /* BlockSize... don't care */
00260             offset += avio_tell(pb);    /* Compute absolute data offset */
00261             if (st->codec->block_align)    /* Assume COMM already parsed */
00262                 goto got_sound;
00263             if (!pb->seekable) {
00264                 av_log(s, AV_LOG_ERROR, "file is not seekable\n");
00265                 return -1;
00266             }
00267             avio_skip(pb, size - 8);
00268             break;
00269         case MKTAG('w', 'a', 'v', 'e'):
00270             if ((uint64_t)size > (1<<30))
00271                 return -1;
00272             st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE);
00273             if (!st->codec->extradata)
00274                 return AVERROR(ENOMEM);
00275             st->codec->extradata_size = size;
00276             avio_read(pb, st->codec->extradata, size);
00277             if (st->codec->codec_id == AV_CODEC_ID_QDM2 && size>=12*4 && !st->codec->block_align)
00278                 st->codec->block_align = AV_RB32(st->codec->extradata+11*4);
00279             break;
00280         case MKTAG('C','H','A','N'):
00281             if(ff_mov_read_chan(s, pb, st, size) < 0)
00282                 return AVERROR_INVALIDDATA;
00283             break;
00284         default: /* Jump */
00285             if (size & 1)   /* Always even aligned */
00286                 size++;
00287             avio_skip(pb, size);
00288         }
00289     }
00290 
00291 got_sound:
00292     if (!st->codec->block_align) {
00293         av_log(s, AV_LOG_ERROR, "could not find COMM tag or invalid block_align value\n");
00294         return -1;
00295     }
00296 
00297     /* Now positioned, get the sound data start and end */
00298     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
00299     st->start_time = 0;
00300     st->duration = st->nb_frames * aiff->block_duration;
00301 
00302     /* Position the stream at the first block */
00303     avio_seek(pb, offset, SEEK_SET);
00304 
00305     return 0;
00306 }
00307 
00308 #define MAX_SIZE 4096
00309 
00310 static int aiff_read_packet(AVFormatContext *s,
00311                             AVPacket *pkt)
00312 {
00313     AVStream *st = s->streams[0];
00314     AIFFInputContext *aiff = s->priv_data;
00315     int64_t max_size;
00316     int res, size;
00317 
00318     /* calculate size of remaining data */
00319     max_size = aiff->data_end - avio_tell(s->pb);
00320     if (max_size <= 0)
00321         return AVERROR_EOF;
00322 
00323     /* Now for that packet */
00324     if (st->codec->block_align >= 33) // GSM, QCLP, IMA4
00325         size = st->codec->block_align;
00326     else
00327         size = (MAX_SIZE / st->codec->block_align) * st->codec->block_align;
00328     size = FFMIN(max_size, size);
00329     res = av_get_packet(s->pb, pkt, size);
00330     if (res < 0)
00331         return res;
00332 
00333     if (size >= st->codec->block_align)
00334         pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
00335     /* Only one stream in an AIFF file */
00336     pkt->stream_index = 0;
00337     pkt->duration     = (res / st->codec->block_align) * aiff->block_duration;
00338     return 0;
00339 }
00340 
00341 AVInputFormat ff_aiff_demuxer = {
00342     .name           = "aiff",
00343     .long_name      = NULL_IF_CONFIG_SMALL("Audio IFF"),
00344     .priv_data_size = sizeof(AIFFInputContext),
00345     .read_probe     = aiff_probe,
00346     .read_header    = aiff_read_header,
00347     .read_packet    = aiff_read_packet,
00348     .read_seek      = ff_pcm_read_seek,
00349     .codec_tag      = (const AVCodecTag* const []){ ff_codec_aiff_tags, 0 },
00350 };