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libavformat/ape.c

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00001 /*
00002  * Monkey's Audio APE demuxer
00003  * Copyright (c) 2007 Benjamin Zores <ben@geexbox.org>
00004  *  based upon libdemac from Dave Chapman.
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00023 #include <stdio.h>
00024 
00025 #include "libavutil/intreadwrite.h"
00026 #include "avformat.h"
00027 #include "internal.h"
00028 #include "apetag.h"
00029 
00030 /* The earliest and latest file formats supported by this library */
00031 #define APE_MIN_VERSION 3950
00032 #define APE_MAX_VERSION 3990
00033 
00034 #define MAC_FORMAT_FLAG_8_BIT                 1 // is 8-bit [OBSOLETE]
00035 #define MAC_FORMAT_FLAG_CRC                   2 // uses the new CRC32 error detection [OBSOLETE]
00036 #define MAC_FORMAT_FLAG_HAS_PEAK_LEVEL        4 // uint32 nPeakLevel after the header [OBSOLETE]
00037 #define MAC_FORMAT_FLAG_24_BIT                8 // is 24-bit [OBSOLETE]
00038 #define MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS    16 // has the number of seek elements after the peak level
00039 #define MAC_FORMAT_FLAG_CREATE_WAV_HEADER    32 // create the wave header on decompression (not stored)
00040 
00041 #define MAC_SUBFRAME_SIZE 4608
00042 
00043 #define APE_EXTRADATA_SIZE 6
00044 
00045 typedef struct {
00046     int64_t pos;
00047     int nblocks;
00048     int size;
00049     int skip;
00050     int64_t pts;
00051 } APEFrame;
00052 
00053 typedef struct {
00054     /* Derived fields */
00055     uint32_t junklength;
00056     uint32_t firstframe;
00057     uint32_t totalsamples;
00058     int currentframe;
00059     APEFrame *frames;
00060 
00061     /* Info from Descriptor Block */
00062     char magic[4];
00063     int16_t fileversion;
00064     int16_t padding1;
00065     uint32_t descriptorlength;
00066     uint32_t headerlength;
00067     uint32_t seektablelength;
00068     uint32_t wavheaderlength;
00069     uint32_t audiodatalength;
00070     uint32_t audiodatalength_high;
00071     uint32_t wavtaillength;
00072     uint8_t md5[16];
00073 
00074     /* Info from Header Block */
00075     uint16_t compressiontype;
00076     uint16_t formatflags;
00077     uint32_t blocksperframe;
00078     uint32_t finalframeblocks;
00079     uint32_t totalframes;
00080     uint16_t bps;
00081     uint16_t channels;
00082     uint32_t samplerate;
00083 
00084     /* Seektable */
00085     uint32_t *seektable;
00086 } APEContext;
00087 
00088 static int ape_probe(AVProbeData * p)
00089 {
00090     if (p->buf[0] == 'M' && p->buf[1] == 'A' && p->buf[2] == 'C' && p->buf[3] == ' ')
00091         return AVPROBE_SCORE_MAX;
00092 
00093     return 0;
00094 }
00095 
00096 static void ape_dumpinfo(AVFormatContext * s, APEContext * ape_ctx)
00097 {
00098 #ifdef DEBUG
00099     int i;
00100 
00101     av_log(s, AV_LOG_DEBUG, "Descriptor Block:\n\n");
00102     av_log(s, AV_LOG_DEBUG, "magic                = \"%c%c%c%c\"\n", ape_ctx->magic[0], ape_ctx->magic[1], ape_ctx->magic[2], ape_ctx->magic[3]);
00103     av_log(s, AV_LOG_DEBUG, "fileversion          = %"PRId16"\n", ape_ctx->fileversion);
00104     av_log(s, AV_LOG_DEBUG, "descriptorlength     = %"PRIu32"\n", ape_ctx->descriptorlength);
00105     av_log(s, AV_LOG_DEBUG, "headerlength         = %"PRIu32"\n", ape_ctx->headerlength);
00106     av_log(s, AV_LOG_DEBUG, "seektablelength      = %"PRIu32"\n", ape_ctx->seektablelength);
00107     av_log(s, AV_LOG_DEBUG, "wavheaderlength      = %"PRIu32"\n", ape_ctx->wavheaderlength);
00108     av_log(s, AV_LOG_DEBUG, "audiodatalength      = %"PRIu32"\n", ape_ctx->audiodatalength);
00109     av_log(s, AV_LOG_DEBUG, "audiodatalength_high = %"PRIu32"\n", ape_ctx->audiodatalength_high);
00110     av_log(s, AV_LOG_DEBUG, "wavtaillength        = %"PRIu32"\n", ape_ctx->wavtaillength);
00111     av_log(s, AV_LOG_DEBUG, "md5                  = ");
00112     for (i = 0; i < 16; i++)
00113          av_log(s, AV_LOG_DEBUG, "%02x", ape_ctx->md5[i]);
00114     av_log(s, AV_LOG_DEBUG, "\n");
00115 
00116     av_log(s, AV_LOG_DEBUG, "\nHeader Block:\n\n");
00117 
00118     av_log(s, AV_LOG_DEBUG, "compressiontype      = %"PRIu16"\n", ape_ctx->compressiontype);
00119     av_log(s, AV_LOG_DEBUG, "formatflags          = %"PRIu16"\n", ape_ctx->formatflags);
00120     av_log(s, AV_LOG_DEBUG, "blocksperframe       = %"PRIu32"\n", ape_ctx->blocksperframe);
00121     av_log(s, AV_LOG_DEBUG, "finalframeblocks     = %"PRIu32"\n", ape_ctx->finalframeblocks);
00122     av_log(s, AV_LOG_DEBUG, "totalframes          = %"PRIu32"\n", ape_ctx->totalframes);
00123     av_log(s, AV_LOG_DEBUG, "bps                  = %"PRIu16"\n", ape_ctx->bps);
00124     av_log(s, AV_LOG_DEBUG, "channels             = %"PRIu16"\n", ape_ctx->channels);
00125     av_log(s, AV_LOG_DEBUG, "samplerate           = %"PRIu32"\n", ape_ctx->samplerate);
00126 
00127     av_log(s, AV_LOG_DEBUG, "\nSeektable\n\n");
00128     if ((ape_ctx->seektablelength / sizeof(uint32_t)) != ape_ctx->totalframes) {
00129         av_log(s, AV_LOG_DEBUG, "No seektable\n");
00130     } else {
00131         for (i = 0; i < ape_ctx->seektablelength / sizeof(uint32_t); i++) {
00132             if (i < ape_ctx->totalframes - 1) {
00133                 av_log(s, AV_LOG_DEBUG, "%8d   %"PRIu32" (%"PRIu32" bytes)\n",
00134                        i, ape_ctx->seektable[i],
00135                        ape_ctx->seektable[i + 1] - ape_ctx->seektable[i]);
00136             } else {
00137                 av_log(s, AV_LOG_DEBUG, "%8d   %"PRIu32"\n", i, ape_ctx->seektable[i]);
00138             }
00139         }
00140     }
00141 
00142     av_log(s, AV_LOG_DEBUG, "\nFrames\n\n");
00143     for (i = 0; i < ape_ctx->totalframes; i++)
00144         av_log(s, AV_LOG_DEBUG, "%8d   %8"PRId64" %8d (%d samples)\n", i,
00145                ape_ctx->frames[i].pos, ape_ctx->frames[i].size,
00146                ape_ctx->frames[i].nblocks);
00147 
00148     av_log(s, AV_LOG_DEBUG, "\nCalculated information:\n\n");
00149     av_log(s, AV_LOG_DEBUG, "junklength           = %"PRIu32"\n", ape_ctx->junklength);
00150     av_log(s, AV_LOG_DEBUG, "firstframe           = %"PRIu32"\n", ape_ctx->firstframe);
00151     av_log(s, AV_LOG_DEBUG, "totalsamples         = %"PRIu32"\n", ape_ctx->totalsamples);
00152 #endif
00153 }
00154 
00155 static int ape_read_header(AVFormatContext * s, AVFormatParameters * ap)
00156 {
00157     AVIOContext *pb = s->pb;
00158     APEContext *ape = s->priv_data;
00159     AVStream *st;
00160     uint32_t tag;
00161     int i;
00162     int total_blocks;
00163     int64_t pts;
00164 
00165     /* Skip any leading junk such as id3v2 tags */
00166     ape->junklength = avio_tell(pb);
00167 
00168     tag = avio_rl32(pb);
00169     if (tag != MKTAG('M', 'A', 'C', ' '))
00170         return -1;
00171 
00172     ape->fileversion = avio_rl16(pb);
00173 
00174     if (ape->fileversion < APE_MIN_VERSION || ape->fileversion > APE_MAX_VERSION) {
00175         av_log(s, AV_LOG_ERROR, "Unsupported file version - %d.%02d\n",
00176                ape->fileversion / 1000, (ape->fileversion % 1000) / 10);
00177         return -1;
00178     }
00179 
00180     if (ape->fileversion >= 3980) {
00181         ape->padding1             = avio_rl16(pb);
00182         ape->descriptorlength     = avio_rl32(pb);
00183         ape->headerlength         = avio_rl32(pb);
00184         ape->seektablelength      = avio_rl32(pb);
00185         ape->wavheaderlength      = avio_rl32(pb);
00186         ape->audiodatalength      = avio_rl32(pb);
00187         ape->audiodatalength_high = avio_rl32(pb);
00188         ape->wavtaillength        = avio_rl32(pb);
00189         avio_read(pb, ape->md5, 16);
00190 
00191         /* Skip any unknown bytes at the end of the descriptor.
00192            This is for future compatibility */
00193         if (ape->descriptorlength > 52)
00194             avio_skip(pb, ape->descriptorlength - 52);
00195 
00196         /* Read header data */
00197         ape->compressiontype      = avio_rl16(pb);
00198         ape->formatflags          = avio_rl16(pb);
00199         ape->blocksperframe       = avio_rl32(pb);
00200         ape->finalframeblocks     = avio_rl32(pb);
00201         ape->totalframes          = avio_rl32(pb);
00202         ape->bps                  = avio_rl16(pb);
00203         ape->channels             = avio_rl16(pb);
00204         ape->samplerate           = avio_rl32(pb);
00205     } else {
00206         ape->descriptorlength = 0;
00207         ape->headerlength = 32;
00208 
00209         ape->compressiontype      = avio_rl16(pb);
00210         ape->formatflags          = avio_rl16(pb);
00211         ape->channels             = avio_rl16(pb);
00212         ape->samplerate           = avio_rl32(pb);
00213         ape->wavheaderlength      = avio_rl32(pb);
00214         ape->wavtaillength        = avio_rl32(pb);
00215         ape->totalframes          = avio_rl32(pb);
00216         ape->finalframeblocks     = avio_rl32(pb);
00217 
00218         if (ape->formatflags & MAC_FORMAT_FLAG_HAS_PEAK_LEVEL) {
00219             avio_skip(pb, 4); /* Skip the peak level */
00220             ape->headerlength += 4;
00221         }
00222 
00223         if (ape->formatflags & MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS) {
00224             ape->seektablelength = avio_rl32(pb);
00225             ape->headerlength += 4;
00226             ape->seektablelength *= sizeof(int32_t);
00227         } else
00228             ape->seektablelength = ape->totalframes * sizeof(int32_t);
00229 
00230         if (ape->formatflags & MAC_FORMAT_FLAG_8_BIT)
00231             ape->bps = 8;
00232         else if (ape->formatflags & MAC_FORMAT_FLAG_24_BIT)
00233             ape->bps = 24;
00234         else
00235             ape->bps = 16;
00236 
00237         if (ape->fileversion >= 3950)
00238             ape->blocksperframe = 73728 * 4;
00239         else if (ape->fileversion >= 3900 || (ape->fileversion >= 3800  && ape->compressiontype >= 4000))
00240             ape->blocksperframe = 73728;
00241         else
00242             ape->blocksperframe = 9216;
00243 
00244         /* Skip any stored wav header */
00245         if (!(ape->formatflags & MAC_FORMAT_FLAG_CREATE_WAV_HEADER))
00246             avio_skip(pb, ape->wavheaderlength);
00247     }
00248 
00249     if(!ape->totalframes){
00250         av_log(s, AV_LOG_ERROR, "No frames in the file!\n");
00251         return AVERROR(EINVAL);
00252     }
00253     if(ape->totalframes > UINT_MAX / sizeof(APEFrame)){
00254         av_log(s, AV_LOG_ERROR, "Too many frames: %"PRIu32"\n",
00255                ape->totalframes);
00256         return -1;
00257     }
00258     if (ape->seektablelength && (ape->seektablelength / sizeof(*ape->seektable)) < ape->totalframes) {
00259         av_log(s, AV_LOG_ERROR,
00260                "Number of seek entries is less than number of frames: %zu vs. %"PRIu32"\n",
00261                ape->seektablelength / sizeof(*ape->seektable), ape->totalframes);
00262         return AVERROR_INVALIDDATA;
00263     }
00264     ape->frames       = av_malloc(ape->totalframes * sizeof(APEFrame));
00265     if(!ape->frames)
00266         return AVERROR(ENOMEM);
00267     ape->firstframe   = ape->junklength + ape->descriptorlength + ape->headerlength + ape->seektablelength + ape->wavheaderlength;
00268     ape->currentframe = 0;
00269 
00270 
00271     ape->totalsamples = ape->finalframeblocks;
00272     if (ape->totalframes > 1)
00273         ape->totalsamples += ape->blocksperframe * (ape->totalframes - 1);
00274 
00275     if (ape->seektablelength > 0) {
00276         ape->seektable = av_malloc(ape->seektablelength);
00277         if (!ape->seektable)
00278             return AVERROR(ENOMEM);
00279         for (i = 0; i < ape->seektablelength / sizeof(uint32_t); i++)
00280             ape->seektable[i] = avio_rl32(pb);
00281     }else{
00282         av_log(s, AV_LOG_ERROR, "Missing seektable\n");
00283         return -1;
00284     }
00285 
00286     ape->frames[0].pos     = ape->firstframe;
00287     ape->frames[0].nblocks = ape->blocksperframe;
00288     ape->frames[0].skip    = 0;
00289     for (i = 1; i < ape->totalframes; i++) {
00290         ape->frames[i].pos      = ape->seektable[i] + ape->junklength;
00291         ape->frames[i].nblocks  = ape->blocksperframe;
00292         ape->frames[i - 1].size = ape->frames[i].pos - ape->frames[i - 1].pos;
00293         ape->frames[i].skip     = (ape->frames[i].pos - ape->frames[0].pos) & 3;
00294     }
00295     ape->frames[ape->totalframes - 1].size    = ape->finalframeblocks * 4;
00296     ape->frames[ape->totalframes - 1].nblocks = ape->finalframeblocks;
00297 
00298     for (i = 0; i < ape->totalframes; i++) {
00299         if(ape->frames[i].skip){
00300             ape->frames[i].pos  -= ape->frames[i].skip;
00301             ape->frames[i].size += ape->frames[i].skip;
00302         }
00303         ape->frames[i].size = (ape->frames[i].size + 3) & ~3;
00304     }
00305 
00306 
00307     ape_dumpinfo(s, ape);
00308 
00309     /* try to read APE tags */
00310     if (pb->seekable) {
00311         ff_ape_parse_tag(s);
00312         avio_seek(pb, 0, SEEK_SET);
00313     }
00314 
00315     av_log(s, AV_LOG_DEBUG, "Decoding file - v%d.%02d, compression level %"PRIu16"\n",
00316            ape->fileversion / 1000, (ape->fileversion % 1000) / 10,
00317            ape->compressiontype);
00318 
00319     /* now we are ready: build format streams */
00320     st = avformat_new_stream(s, NULL);
00321     if (!st)
00322         return -1;
00323 
00324     total_blocks = (ape->totalframes == 0) ? 0 : ((ape->totalframes - 1) * ape->blocksperframe) + ape->finalframeblocks;
00325 
00326     st->codec->codec_type      = AVMEDIA_TYPE_AUDIO;
00327     st->codec->codec_id        = CODEC_ID_APE;
00328     st->codec->codec_tag       = MKTAG('A', 'P', 'E', ' ');
00329     st->codec->channels        = ape->channels;
00330     st->codec->sample_rate     = ape->samplerate;
00331     st->codec->bits_per_coded_sample = ape->bps;
00332     st->codec->frame_size      = MAC_SUBFRAME_SIZE;
00333 
00334     st->nb_frames = ape->totalframes;
00335     st->start_time = 0;
00336     st->duration  = total_blocks / MAC_SUBFRAME_SIZE;
00337     avpriv_set_pts_info(st, 64, MAC_SUBFRAME_SIZE, ape->samplerate);
00338 
00339     st->codec->extradata = av_malloc(APE_EXTRADATA_SIZE);
00340     st->codec->extradata_size = APE_EXTRADATA_SIZE;
00341     AV_WL16(st->codec->extradata + 0, ape->fileversion);
00342     AV_WL16(st->codec->extradata + 2, ape->compressiontype);
00343     AV_WL16(st->codec->extradata + 4, ape->formatflags);
00344 
00345     pts = 0;
00346     for (i = 0; i < ape->totalframes; i++) {
00347         ape->frames[i].pts = pts;
00348         av_add_index_entry(st, ape->frames[i].pos, ape->frames[i].pts, 0, 0, AVINDEX_KEYFRAME);
00349         pts += ape->blocksperframe / MAC_SUBFRAME_SIZE;
00350     }
00351 
00352     return 0;
00353 }
00354 
00355 static int ape_read_packet(AVFormatContext * s, AVPacket * pkt)
00356 {
00357     int ret;
00358     int nblocks;
00359     APEContext *ape = s->priv_data;
00360     uint32_t extra_size = 8;
00361 
00362     if (url_feof(s->pb))
00363         return AVERROR(EIO);
00364     if (ape->currentframe > ape->totalframes)
00365         return AVERROR(EIO);
00366 
00367     avio_seek (s->pb, ape->frames[ape->currentframe].pos, SEEK_SET);
00368 
00369     /* Calculate how many blocks there are in this frame */
00370     if (ape->currentframe == (ape->totalframes - 1))
00371         nblocks = ape->finalframeblocks;
00372     else
00373         nblocks = ape->blocksperframe;
00374 
00375     if (av_new_packet(pkt,  ape->frames[ape->currentframe].size + extra_size) < 0)
00376         return AVERROR(ENOMEM);
00377 
00378     AV_WL32(pkt->data    , nblocks);
00379     AV_WL32(pkt->data + 4, ape->frames[ape->currentframe].skip);
00380     ret = avio_read(s->pb, pkt->data + extra_size, ape->frames[ape->currentframe].size);
00381 
00382     pkt->pts = ape->frames[ape->currentframe].pts;
00383     pkt->stream_index = 0;
00384 
00385     /* note: we need to modify the packet size here to handle the last
00386        packet */
00387     pkt->size = ret + extra_size;
00388 
00389     ape->currentframe++;
00390 
00391     return 0;
00392 }
00393 
00394 static int ape_read_close(AVFormatContext * s)
00395 {
00396     APEContext *ape = s->priv_data;
00397 
00398     av_freep(&ape->frames);
00399     av_freep(&ape->seektable);
00400     return 0;
00401 }
00402 
00403 static int ape_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
00404 {
00405     AVStream *st = s->streams[stream_index];
00406     APEContext *ape = s->priv_data;
00407     int index = av_index_search_timestamp(st, timestamp, flags);
00408 
00409     if (index < 0)
00410         return -1;
00411 
00412     ape->currentframe = index;
00413     return 0;
00414 }
00415 
00416 AVInputFormat ff_ape_demuxer = {
00417     .name           = "ape",
00418     .long_name      = NULL_IF_CONFIG_SMALL("Monkey's Audio"),
00419     .priv_data_size = sizeof(APEContext),
00420     .read_probe     = ape_probe,
00421     .read_header    = ape_read_header,
00422     .read_packet    = ape_read_packet,
00423     .read_close     = ape_read_close,
00424     .read_seek      = ape_read_seek,
00425     .extensions = "ape,apl,mac"
00426 };
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