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

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