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 #include "mov_chan.h"
00032 
00033 #define AIFF                    0
00034 #define AIFF_C_VERSION1         0xA2805140
00035 
00036 typedef struct {
00037     int64_t data_end;
00038     int block_duration;
00039 } AIFFInputContext;
00040 
00041 static enum AVCodecID aiff_codec_get_id(int bps)
00042 {
00043     if (bps <= 8)
00044         return AV_CODEC_ID_PCM_S8;
00045     if (bps <= 16)
00046         return AV_CODEC_ID_PCM_S16BE;
00047     if (bps <= 24)
00048         return AV_CODEC_ID_PCM_S24BE;
00049     if (bps <= 32)
00050         return AV_CODEC_ID_PCM_S32BE;
00051 
00052     /* bigger than 32 isn't allowed  */
00053     return AV_CODEC_ID_NONE;
00054 }
00055 
00056 /* returns the size of the found tag */
00057 static int get_tag(AVIOContext *pb, uint32_t * tag)
00058 {
00059     int size;
00060 
00061     if (url_feof(pb))
00062         return AVERROR(EIO);
00063 
00064     *tag = avio_rl32(pb);
00065     size = avio_rb32(pb);
00066 
00067     if (size < 0)
00068         size = 0x7fffffff;
00069 
00070     return size;
00071 }
00072 
00073 /* Metadata string read */
00074 static void get_meta(AVFormatContext *s, const char *key, int size)
00075 {
00076     uint8_t *str = av_malloc(size+1);
00077 
00078     if (str) {
00079         int res = avio_read(s->pb, str, size);
00080         if (res < 0){
00081             av_free(str);
00082             return;
00083         }
00084         size += (size&1)-res;
00085         str[res] = 0;
00086         av_dict_set(&s->metadata, key, str, AV_DICT_DONT_STRDUP_VAL);
00087     }else
00088         size+= size&1;
00089 
00090     avio_skip(s->pb, size);
00091 }
00092 
00093 /* Returns the number of sound data frames or negative on error */
00094 static unsigned int get_aiff_header(AVFormatContext *s, int size,
00095                                     unsigned version)
00096 {
00097     AVIOContext *pb        = s->pb;
00098     AVCodecContext *codec  = s->streams[0]->codec;
00099     AIFFInputContext *aiff = s->priv_data;
00100     int exp;
00101     uint64_t val;
00102     double sample_rate;
00103     unsigned int num_frames;
00104 
00105     if (size & 1)
00106         size++;
00107     codec->codec_type = AVMEDIA_TYPE_AUDIO;
00108     codec->channels = avio_rb16(pb);
00109     num_frames = avio_rb32(pb);
00110     codec->bits_per_coded_sample = avio_rb16(pb);
00111 
00112     exp = avio_rb16(pb);
00113     val = avio_rb64(pb);
00114     sample_rate = ldexp(val, exp - 16383 - 63);
00115     codec->sample_rate = sample_rate;
00116     size -= 18;
00117 
00118     /* get codec id for AIFF-C */
00119     if (version == AIFF_C_VERSION1) {
00120         codec->codec_tag = avio_rl32(pb);
00121         codec->codec_id  = ff_codec_get_id(ff_codec_aiff_tags, codec->codec_tag);
00122         size -= 4;
00123     }
00124 
00125     if (version != AIFF_C_VERSION1 || codec->codec_id == AV_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         aiff->block_duration = 1;
00129     } else {
00130         switch (codec->codec_id) {
00131         case AV_CODEC_ID_PCM_F32BE:
00132         case AV_CODEC_ID_PCM_F64BE:
00133         case AV_CODEC_ID_PCM_S16LE:
00134         case AV_CODEC_ID_PCM_ALAW:
00135         case AV_CODEC_ID_PCM_MULAW:
00136             aiff->block_duration = 1;
00137             break;
00138         case AV_CODEC_ID_ADPCM_IMA_QT:
00139             codec->block_align = 34*codec->channels;
00140             break;
00141         case AV_CODEC_ID_MACE3:
00142             codec->block_align = 2*codec->channels;
00143             break;
00144         case AV_CODEC_ID_MACE6:
00145             codec->block_align = 1*codec->channels;
00146             break;
00147         case AV_CODEC_ID_GSM:
00148             codec->block_align = 33;
00149             break;
00150         case AV_CODEC_ID_QCELP:
00151             codec->block_align = 35;
00152             break;
00153         default:
00154             aiff->block_duration = 1;
00155             break;
00156         }
00157         if (codec->block_align > 0)
00158             aiff->block_duration = av_get_audio_frame_duration(codec,
00159                                                                codec->block_align);
00160     }
00161 
00162     /* Block align needs to be computed in all cases, as the definition
00163      * is specific to applications -> here we use the WAVE format definition */
00164     if (!codec->block_align)
00165         codec->block_align = (av_get_bits_per_sample(codec->codec_id) * codec->channels) >> 3;
00166 
00167     if (aiff->block_duration) {
00168         codec->bit_rate = codec->sample_rate * (codec->block_align << 3) /
00169                           aiff->block_duration;
00170     }
00171 
00172     /* Chunk is over */
00173     if (size)
00174         avio_skip(pb, size);
00175 
00176     return num_frames;
00177 }
00178 
00179 static int aiff_probe(AVProbeData *p)
00180 {
00181     /* check file header */
00182     if (p->buf[0] == 'F' && p->buf[1] == 'O' &&
00183         p->buf[2] == 'R' && p->buf[3] == 'M' &&
00184         p->buf[8] == 'A' && p->buf[9] == 'I' &&
00185         p->buf[10] == 'F' && (p->buf[11] == 'F' || p->buf[11] == 'C'))
00186         return AVPROBE_SCORE_MAX;
00187     else
00188         return 0;
00189 }
00190 
00191 /* aiff input */
00192 static int aiff_read_header(AVFormatContext *s)
00193 {
00194     int ret, size, filesize;
00195     int64_t offset = 0;
00196     uint32_t tag;
00197     unsigned version = AIFF_C_VERSION1;
00198     AVIOContext *pb = s->pb;
00199     AVStream * st;
00200     AIFFInputContext *aiff = s->priv_data;
00201     ID3v2ExtraMeta *id3v2_extra_meta = NULL;
00202 
00203     /* check FORM header */
00204     filesize = get_tag(pb, &tag);
00205     if (filesize < 0 || tag != MKTAG('F', 'O', 'R', 'M'))
00206         return AVERROR_INVALIDDATA;
00207 
00208     /* AIFF data type */
00209     tag = avio_rl32(pb);
00210     if (tag == MKTAG('A', 'I', 'F', 'F'))       /* Got an AIFF file */
00211         version = AIFF;
00212     else if (tag != MKTAG('A', 'I', 'F', 'C'))  /* An AIFF-C file then */
00213         return AVERROR_INVALIDDATA;
00214 
00215     filesize -= 4;
00216 
00217     st = avformat_new_stream(s, NULL);
00218     if (!st)
00219         return AVERROR(ENOMEM);
00220 
00221     while (filesize > 0) {
00222         /* parse different chunks */
00223         size = get_tag(pb, &tag);
00224         if (size < 0)
00225             return size;
00226 
00227         filesize -= size + 8;
00228 
00229         switch (tag) {
00230         case MKTAG('C', 'O', 'M', 'M'):     /* Common chunk */
00231             /* Then for the complete header info */
00232             st->nb_frames = get_aiff_header(s, size, version);
00233             if (st->nb_frames < 0)
00234                 return st->nb_frames;
00235             if (offset > 0) // COMM is after SSND
00236                 goto got_sound;
00237             break;
00238         case MKTAG('I', 'D', '3', ' '):
00239             ff_id3v2_read(s, ID3v2_DEFAULT_MAGIC, &id3v2_extra_meta);
00240             if (id3v2_extra_meta)
00241                 if ((ret = ff_id3v2_parse_apic(s, &id3v2_extra_meta)) < 0) {
00242                     ff_id3v2_free_extra_meta(&id3v2_extra_meta);
00243                     return ret;
00244                 }
00245             ff_id3v2_free_extra_meta(&id3v2_extra_meta);
00246             break;
00247         case MKTAG('F', 'V', 'E', 'R'):     /* Version chunk */
00248             version = avio_rb32(pb);
00249             break;
00250         case MKTAG('N', 'A', 'M', 'E'):     /* Sample name chunk */
00251             get_meta(s, "title"    , size);
00252             break;
00253         case MKTAG('A', 'U', 'T', 'H'):     /* Author chunk */
00254             get_meta(s, "author"   , size);
00255             break;
00256         case MKTAG('(', 'c', ')', ' '):     /* Copyright chunk */
00257             get_meta(s, "copyright", size);
00258             break;
00259         case MKTAG('A', 'N', 'N', 'O'):     /* Annotation chunk */
00260             get_meta(s, "comment"  , size);
00261             break;
00262         case MKTAG('S', 'S', 'N', 'D'):     /* Sampled sound chunk */
00263             aiff->data_end = avio_tell(pb) + size;
00264             offset = avio_rb32(pb);      /* Offset of sound data */
00265             avio_rb32(pb);               /* BlockSize... don't care */
00266             offset += avio_tell(pb);    /* Compute absolute data offset */
00267             if (st->codec->block_align && !pb->seekable)    /* Assume COMM already parsed */
00268                 goto got_sound;
00269             if (!pb->seekable) {
00270                 av_log(s, AV_LOG_ERROR, "file is not seekable\n");
00271                 return -1;
00272             }
00273             avio_skip(pb, size - 8);
00274             break;
00275         case MKTAG('w', 'a', 'v', 'e'):
00276             if ((uint64_t)size > (1<<30))
00277                 return -1;
00278             st->codec->extradata = av_mallocz(size + FF_INPUT_BUFFER_PADDING_SIZE);
00279             if (!st->codec->extradata)
00280                 return AVERROR(ENOMEM);
00281             st->codec->extradata_size = size;
00282             avio_read(pb, st->codec->extradata, size);
00283             if (st->codec->codec_id == AV_CODEC_ID_QDM2 && size>=12*4 && !st->codec->block_align)
00284                 st->codec->block_align = AV_RB32(st->codec->extradata+11*4);
00285             break;
00286         case MKTAG('C','H','A','N'):
00287             if(ff_mov_read_chan(s, pb, st, size) < 0)
00288                 return AVERROR_INVALIDDATA;
00289             break;
00290         default: /* Jump */
00291             if (size & 1)   /* Always even aligned */
00292                 size++;
00293             avio_skip(pb, size);
00294         }
00295     }
00296 
00297 got_sound:
00298     if (!st->codec->block_align) {
00299         av_log(s, AV_LOG_ERROR, "could not find COMM tag or invalid block_align value\n");
00300         return -1;
00301     }
00302 
00303     /* Now positioned, get the sound data start and end */
00304     avpriv_set_pts_info(st, 64, 1, st->codec->sample_rate);
00305     st->start_time = 0;
00306     st->duration = st->nb_frames * aiff->block_duration;
00307 
00308     /* Position the stream at the first block */
00309     avio_seek(pb, offset, SEEK_SET);
00310 
00311     return 0;
00312 }
00313 
00314 #define MAX_SIZE 4096
00315 
00316 static int aiff_read_packet(AVFormatContext *s,
00317                             AVPacket *pkt)
00318 {
00319     AVStream *st = s->streams[0];
00320     AIFFInputContext *aiff = s->priv_data;
00321     int64_t max_size;
00322     int res, size;
00323 
00324     /* calculate size of remaining data */
00325     max_size = aiff->data_end - avio_tell(s->pb);
00326     if (max_size <= 0)
00327         return AVERROR_EOF;
00328 
00329     /* Now for that packet */
00330     if (st->codec->block_align >= 33) // GSM, QCLP, IMA4
00331         size = st->codec->block_align;
00332     else
00333         size = (MAX_SIZE / st->codec->block_align) * st->codec->block_align;
00334     size = FFMIN(max_size, size);
00335     res = av_get_packet(s->pb, pkt, size);
00336     if (res < 0)
00337         return res;
00338 
00339     if (size >= st->codec->block_align)
00340         pkt->flags &= ~AV_PKT_FLAG_CORRUPT;
00341     /* Only one stream in an AIFF file */
00342     pkt->stream_index = 0;
00343     pkt->duration     = (res / st->codec->block_align) * aiff->block_duration;
00344     return 0;
00345 }
00346 
00347 AVInputFormat ff_aiff_demuxer = {
00348     .name           = "aiff",
00349     .long_name      = NULL_IF_CONFIG_SMALL("Audio IFF"),
00350     .priv_data_size = sizeof(AIFFInputContext),
00351     .read_probe     = aiff_probe,
00352     .read_header    = aiff_read_header,
00353     .read_packet    = aiff_read_packet,
00354     .read_seek      = ff_pcm_read_seek,
00355     .codec_tag      = (const AVCodecTag* const []){ ff_codec_aiff_tags, 0 },
00356 };