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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 
00028 #define ENABLE_DEBUG 0
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 /* APE tags */
00046 #define APE_TAG_VERSION               2000
00047 #define APE_TAG_FOOTER_BYTES          32
00048 #define APE_TAG_FLAG_CONTAINS_HEADER  (1 << 31)
00049 #define APE_TAG_FLAG_IS_HEADER        (1 << 29)
00050 
00051 typedef struct {
00052     int64_t pos;
00053     int nblocks;
00054     int size;
00055     int skip;
00056     int64_t pts;
00057 } APEFrame;
00058 
00059 typedef struct {
00060     /* Derived fields */
00061     uint32_t junklength;
00062     uint32_t firstframe;
00063     uint32_t totalsamples;
00064     int currentframe;
00065     APEFrame *frames;
00066 
00067     /* Info from Descriptor Block */
00068     char magic[4];
00069     int16_t fileversion;
00070     int16_t padding1;
00071     uint32_t descriptorlength;
00072     uint32_t headerlength;
00073     uint32_t seektablelength;
00074     uint32_t wavheaderlength;
00075     uint32_t audiodatalength;
00076     uint32_t audiodatalength_high;
00077     uint32_t wavtaillength;
00078     uint8_t md5[16];
00079 
00080     /* Info from Header Block */
00081     uint16_t compressiontype;
00082     uint16_t formatflags;
00083     uint32_t blocksperframe;
00084     uint32_t finalframeblocks;
00085     uint32_t totalframes;
00086     uint16_t bps;
00087     uint16_t channels;
00088     uint32_t samplerate;
00089 
00090     /* Seektable */
00091     uint32_t *seektable;
00092 } APEContext;
00093 
00094 static void ape_tag_read_field(AVFormatContext *s)
00095 {
00096     ByteIOContext *pb = s->pb;
00097     uint8_t key[1024], value[1024];
00098     uint32_t size;
00099     int i, l;
00100 
00101     size = get_le32(pb);  /* field size */
00102     url_fskip(pb, 4);     /* skip field flags */
00103 
00104     for (i=0; pb->buf_ptr[i]!='0' && pb->buf_ptr[i]>=0x20 && pb->buf_ptr[i]<=0x7E; i++);
00105 
00106     l = FFMIN(i,    sizeof(key) -1);
00107     get_buffer(pb, key,  l);
00108     key[l]  = 0;
00109     url_fskip(pb, 1 + i-l);
00110     l = FFMIN(size, sizeof(value)-1);
00111     get_buffer(pb, value, l);
00112     value[l] = 0;
00113     url_fskip(pb, size-l);
00114     if (l < size)
00115         av_log(s, AV_LOG_WARNING, "Too long '%s' tag was truncated.\n", key);
00116     av_metadata_set(&s->metadata, key, value);
00117 }
00118 
00119 static void ape_parse_tag(AVFormatContext *s)
00120 {
00121     ByteIOContext *pb = s->pb;
00122     int file_size = url_fsize(pb);
00123     uint32_t val, fields, tag_bytes;
00124     uint8_t buf[8];
00125     int i;
00126 
00127     if (file_size < APE_TAG_FOOTER_BYTES)
00128         return;
00129 
00130     url_fseek(pb, file_size - APE_TAG_FOOTER_BYTES, SEEK_SET);
00131 
00132     get_buffer(pb, buf, 8);    /* APETAGEX */
00133     if (strncmp(buf, "APETAGEX", 8)) {
00134         return;
00135     }
00136 
00137     val = get_le32(pb);        /* APE tag version */
00138     if (val > APE_TAG_VERSION) {
00139         av_log(s, AV_LOG_ERROR, "Unsupported tag version. (>=%d)\n", APE_TAG_VERSION);
00140         return;
00141     }
00142 
00143     tag_bytes = get_le32(pb);  /* tag size */
00144     if (tag_bytes - APE_TAG_FOOTER_BYTES > (1024 * 1024 * 16)) {
00145         av_log(s, AV_LOG_ERROR, "Tag size is way too big\n");
00146         return;
00147     }
00148 
00149     fields = get_le32(pb);     /* number of fields */
00150     if (fields > 65536) {
00151         av_log(s, AV_LOG_ERROR, "Too many tag fields (%d)\n", fields);
00152         return;
00153     }
00154 
00155     val = get_le32(pb);        /* flags */
00156     if (val & APE_TAG_FLAG_IS_HEADER) {
00157         av_log(s, AV_LOG_ERROR, "APE Tag is a header\n");
00158         return;
00159     }
00160 
00161     if (val & APE_TAG_FLAG_CONTAINS_HEADER)
00162         tag_bytes += 2*APE_TAG_FOOTER_BYTES;
00163 
00164     url_fseek(pb, file_size - tag_bytes, SEEK_SET);
00165 
00166     for (i=0; i<fields; i++)
00167         ape_tag_read_field(s);
00168 
00169 #if ENABLE_DEBUG
00170     av_log(s, AV_LOG_DEBUG, "\nAPE Tags:\n\n");
00171     av_log(s, AV_LOG_DEBUG, "title     = %s\n", s->title);
00172     av_log(s, AV_LOG_DEBUG, "author    = %s\n", s->author);
00173     av_log(s, AV_LOG_DEBUG, "copyright = %s\n", s->copyright);
00174     av_log(s, AV_LOG_DEBUG, "comment   = %s\n", s->comment);
00175     av_log(s, AV_LOG_DEBUG, "album     = %s\n", s->album);
00176     av_log(s, AV_LOG_DEBUG, "year      = %d\n", s->year);
00177     av_log(s, AV_LOG_DEBUG, "track     = %d\n", s->track);
00178     av_log(s, AV_LOG_DEBUG, "genre     = %s\n", s->genre);
00179 #endif
00180 }
00181 
00182 static int ape_probe(AVProbeData * p)
00183 {
00184     if (p->buf[0] == 'M' && p->buf[1] == 'A' && p->buf[2] == 'C' && p->buf[3] == ' ')
00185         return AVPROBE_SCORE_MAX;
00186 
00187     return 0;
00188 }
00189 
00190 static void ape_dumpinfo(AVFormatContext * s, APEContext * ape_ctx)
00191 {
00192 #if ENABLE_DEBUG
00193     int i;
00194 
00195     av_log(s, AV_LOG_DEBUG, "Descriptor Block:\n\n");
00196     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]);
00197     av_log(s, AV_LOG_DEBUG, "fileversion          = %d\n", ape_ctx->fileversion);
00198     av_log(s, AV_LOG_DEBUG, "descriptorlength     = %d\n", ape_ctx->descriptorlength);
00199     av_log(s, AV_LOG_DEBUG, "headerlength         = %d\n", ape_ctx->headerlength);
00200     av_log(s, AV_LOG_DEBUG, "seektablelength      = %d\n", ape_ctx->seektablelength);
00201     av_log(s, AV_LOG_DEBUG, "wavheaderlength      = %d\n", ape_ctx->wavheaderlength);
00202     av_log(s, AV_LOG_DEBUG, "audiodatalength      = %d\n", ape_ctx->audiodatalength);
00203     av_log(s, AV_LOG_DEBUG, "audiodatalength_high = %d\n", ape_ctx->audiodatalength_high);
00204     av_log(s, AV_LOG_DEBUG, "wavtaillength        = %d\n", ape_ctx->wavtaillength);
00205     av_log(s, AV_LOG_DEBUG, "md5                  = ");
00206     for (i = 0; i < 16; i++)
00207          av_log(s, AV_LOG_DEBUG, "%02x", ape_ctx->md5[i]);
00208     av_log(s, AV_LOG_DEBUG, "\n");
00209 
00210     av_log(s, AV_LOG_DEBUG, "\nHeader Block:\n\n");
00211 
00212     av_log(s, AV_LOG_DEBUG, "compressiontype      = %d\n", ape_ctx->compressiontype);
00213     av_log(s, AV_LOG_DEBUG, "formatflags          = %d\n", ape_ctx->formatflags);
00214     av_log(s, AV_LOG_DEBUG, "blocksperframe       = %d\n", ape_ctx->blocksperframe);
00215     av_log(s, AV_LOG_DEBUG, "finalframeblocks     = %d\n", ape_ctx->finalframeblocks);
00216     av_log(s, AV_LOG_DEBUG, "totalframes          = %d\n", ape_ctx->totalframes);
00217     av_log(s, AV_LOG_DEBUG, "bps                  = %d\n", ape_ctx->bps);
00218     av_log(s, AV_LOG_DEBUG, "channels             = %d\n", ape_ctx->channels);
00219     av_log(s, AV_LOG_DEBUG, "samplerate           = %d\n", ape_ctx->samplerate);
00220 
00221     av_log(s, AV_LOG_DEBUG, "\nSeektable\n\n");
00222     if ((ape_ctx->seektablelength / sizeof(uint32_t)) != ape_ctx->totalframes) {
00223         av_log(s, AV_LOG_DEBUG, "No seektable\n");
00224     } else {
00225         for (i = 0; i < ape_ctx->seektablelength / sizeof(uint32_t); i++) {
00226             if (i < ape_ctx->totalframes - 1) {
00227                 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]);
00228             } else {
00229                 av_log(s, AV_LOG_DEBUG, "%8d   %d\n", i, ape_ctx->seektable[i]);
00230             }
00231         }
00232     }
00233 
00234     av_log(s, AV_LOG_DEBUG, "\nFrames\n\n");
00235     for (i = 0; i < ape_ctx->totalframes; i++)
00236         av_log(s, AV_LOG_DEBUG, "%8d   %8lld %8d (%d samples)\n", i, ape_ctx->frames[i].pos, ape_ctx->frames[i].size, ape_ctx->frames[i].nblocks);
00237 
00238     av_log(s, AV_LOG_DEBUG, "\nCalculated information:\n\n");
00239     av_log(s, AV_LOG_DEBUG, "junklength           = %d\n", ape_ctx->junklength);
00240     av_log(s, AV_LOG_DEBUG, "firstframe           = %d\n", ape_ctx->firstframe);
00241     av_log(s, AV_LOG_DEBUG, "totalsamples         = %d\n", ape_ctx->totalsamples);
00242 #endif
00243 }
00244 
00245 static int ape_read_header(AVFormatContext * s, AVFormatParameters * ap)
00246 {
00247     ByteIOContext *pb = s->pb;
00248     APEContext *ape = s->priv_data;
00249     AVStream *st;
00250     uint32_t tag;
00251     int i;
00252     int total_blocks;
00253     int64_t pts;
00254 
00255     /* TODO: Skip any leading junk such as id3v2 tags */
00256     ape->junklength = 0;
00257 
00258     tag = get_le32(pb);
00259     if (tag != MKTAG('M', 'A', 'C', ' '))
00260         return -1;
00261 
00262     ape->fileversion = get_le16(pb);
00263 
00264     if (ape->fileversion < APE_MIN_VERSION || ape->fileversion > APE_MAX_VERSION) {
00265         av_log(s, AV_LOG_ERROR, "Unsupported file version - %d.%02d\n", ape->fileversion / 1000, (ape->fileversion % 1000) / 10);
00266         return -1;
00267     }
00268 
00269     if (ape->fileversion >= 3980) {
00270         ape->padding1             = get_le16(pb);
00271         ape->descriptorlength     = get_le32(pb);
00272         ape->headerlength         = get_le32(pb);
00273         ape->seektablelength      = get_le32(pb);
00274         ape->wavheaderlength      = get_le32(pb);
00275         ape->audiodatalength      = get_le32(pb);
00276         ape->audiodatalength_high = get_le32(pb);
00277         ape->wavtaillength        = get_le32(pb);
00278         get_buffer(pb, ape->md5, 16);
00279 
00280         /* Skip any unknown bytes at the end of the descriptor.
00281            This is for future compatibility */
00282         if (ape->descriptorlength > 52)
00283             url_fseek(pb, ape->descriptorlength - 52, SEEK_CUR);
00284 
00285         /* Read header data */
00286         ape->compressiontype      = get_le16(pb);
00287         ape->formatflags          = get_le16(pb);
00288         ape->blocksperframe       = get_le32(pb);
00289         ape->finalframeblocks     = get_le32(pb);
00290         ape->totalframes          = get_le32(pb);
00291         ape->bps                  = get_le16(pb);
00292         ape->channels             = get_le16(pb);
00293         ape->samplerate           = get_le32(pb);
00294     } else {
00295         ape->descriptorlength = 0;
00296         ape->headerlength = 32;
00297 
00298         ape->compressiontype      = get_le16(pb);
00299         ape->formatflags          = get_le16(pb);
00300         ape->channels             = get_le16(pb);
00301         ape->samplerate           = get_le32(pb);
00302         ape->wavheaderlength      = get_le32(pb);
00303         ape->wavtaillength        = get_le32(pb);
00304         ape->totalframes          = get_le32(pb);
00305         ape->finalframeblocks     = get_le32(pb);
00306 
00307         if (ape->formatflags & MAC_FORMAT_FLAG_HAS_PEAK_LEVEL) {
00308             url_fseek(pb, 4, SEEK_CUR); /* Skip the peak level */
00309             ape->headerlength += 4;
00310         }
00311 
00312         if (ape->formatflags & MAC_FORMAT_FLAG_HAS_SEEK_ELEMENTS) {
00313             ape->seektablelength = get_le32(pb);
00314             ape->headerlength += 4;
00315             ape->seektablelength *= sizeof(int32_t);
00316         } else
00317             ape->seektablelength = ape->totalframes * sizeof(int32_t);
00318 
00319         if (ape->formatflags & MAC_FORMAT_FLAG_8_BIT)
00320             ape->bps = 8;
00321         else if (ape->formatflags & MAC_FORMAT_FLAG_24_BIT)
00322             ape->bps = 24;
00323         else
00324             ape->bps = 16;
00325 
00326         if (ape->fileversion >= 3950)
00327             ape->blocksperframe = 73728 * 4;
00328         else if (ape->fileversion >= 3900 || (ape->fileversion >= 3800  && ape->compressiontype >= 4000))
00329             ape->blocksperframe = 73728;
00330         else
00331             ape->blocksperframe = 9216;
00332 
00333         /* Skip any stored wav header */
00334         if (!(ape->formatflags & MAC_FORMAT_FLAG_CREATE_WAV_HEADER))
00335             url_fskip(pb, ape->wavheaderlength);
00336     }
00337 
00338     if(!ape->totalframes){
00339         av_log(s, AV_LOG_ERROR, "No frames in the file!\n");
00340         return AVERROR(EINVAL);
00341     }
00342     if(ape->totalframes > UINT_MAX / sizeof(APEFrame)){
00343         av_log(s, AV_LOG_ERROR, "Too many frames: %d\n", ape->totalframes);
00344         return -1;
00345     }
00346     ape->frames       = av_malloc(ape->totalframes * sizeof(APEFrame));
00347     if(!ape->frames)
00348         return AVERROR_NOMEM;
00349     ape->firstframe   = ape->junklength + ape->descriptorlength + ape->headerlength + ape->seektablelength + ape->wavheaderlength;
00350     ape->currentframe = 0;
00351 
00352 
00353     ape->totalsamples = ape->finalframeblocks;
00354     if (ape->totalframes > 1)
00355         ape->totalsamples += ape->blocksperframe * (ape->totalframes - 1);
00356 
00357     if (ape->seektablelength > 0) {
00358         ape->seektable = av_malloc(ape->seektablelength);
00359         for (i = 0; i < ape->seektablelength / sizeof(uint32_t); i++)
00360             ape->seektable[i] = get_le32(pb);
00361     }
00362 
00363     ape->frames[0].pos     = ape->firstframe;
00364     ape->frames[0].nblocks = ape->blocksperframe;
00365     ape->frames[0].skip    = 0;
00366     for (i = 1; i < ape->totalframes; i++) {
00367         ape->frames[i].pos      = ape->seektable[i]; //ape->frames[i-1].pos + ape->blocksperframe;
00368         ape->frames[i].nblocks  = ape->blocksperframe;
00369         ape->frames[i - 1].size = ape->frames[i].pos - ape->frames[i - 1].pos;
00370         ape->frames[i].skip     = (ape->frames[i].pos - ape->frames[0].pos) & 3;
00371     }
00372     ape->frames[ape->totalframes - 1].size    = ape->finalframeblocks * 4;
00373     ape->frames[ape->totalframes - 1].nblocks = ape->finalframeblocks;
00374 
00375     for (i = 0; i < ape->totalframes; i++) {
00376         if(ape->frames[i].skip){
00377             ape->frames[i].pos  -= ape->frames[i].skip;
00378             ape->frames[i].size += ape->frames[i].skip;
00379         }
00380         ape->frames[i].size = (ape->frames[i].size + 3) & ~3;
00381     }
00382 
00383 
00384     ape_dumpinfo(s, ape);
00385 
00386     /* try to read APE tags */
00387     if (!url_is_streamed(pb)) {
00388         ape_parse_tag(s);
00389         url_fseek(pb, 0, SEEK_SET);
00390     }
00391 
00392     av_log(s, AV_LOG_DEBUG, "Decoding file - v%d.%02d, compression level %d\n", ape->fileversion / 1000, (ape->fileversion % 1000) / 10, ape->compressiontype);
00393 
00394     /* now we are ready: build format streams */
00395     st = av_new_stream(s, 0);
00396     if (!st)
00397         return -1;
00398 
00399     total_blocks = (ape->totalframes == 0) ? 0 : ((ape->totalframes - 1) * ape->blocksperframe) + ape->finalframeblocks;
00400 
00401     st->codec->codec_type      = CODEC_TYPE_AUDIO;
00402     st->codec->codec_id        = CODEC_ID_APE;
00403     st->codec->codec_tag       = MKTAG('A', 'P', 'E', ' ');
00404     st->codec->channels        = ape->channels;
00405     st->codec->sample_rate     = ape->samplerate;
00406     st->codec->bits_per_coded_sample = ape->bps;
00407     st->codec->frame_size      = MAC_SUBFRAME_SIZE;
00408 
00409     st->nb_frames = ape->totalframes;
00410     s->start_time = 0;
00411     s->duration   = (int64_t) total_blocks * AV_TIME_BASE / ape->samplerate;
00412     av_set_pts_info(st, 64, MAC_SUBFRAME_SIZE, ape->samplerate);
00413 
00414     st->codec->extradata = av_malloc(APE_EXTRADATA_SIZE);
00415     st->codec->extradata_size = APE_EXTRADATA_SIZE;
00416     AV_WL16(st->codec->extradata + 0, ape->fileversion);
00417     AV_WL16(st->codec->extradata + 2, ape->compressiontype);
00418     AV_WL16(st->codec->extradata + 4, ape->formatflags);
00419 
00420     pts = 0;
00421     for (i = 0; i < ape->totalframes; i++) {
00422         ape->frames[i].pts = pts;
00423         av_add_index_entry(st, ape->frames[i].pos, ape->frames[i].pts, 0, 0, AVINDEX_KEYFRAME);
00424         pts += ape->blocksperframe / MAC_SUBFRAME_SIZE;
00425     }
00426 
00427     return 0;
00428 }
00429 
00430 static int ape_read_packet(AVFormatContext * s, AVPacket * pkt)
00431 {
00432     int ret;
00433     int nblocks;
00434     APEContext *ape = s->priv_data;
00435     uint32_t extra_size = 8;
00436 
00437     if (url_feof(s->pb))
00438         return AVERROR_IO;
00439     if (ape->currentframe > ape->totalframes)
00440         return AVERROR_IO;
00441 
00442     url_fseek (s->pb, ape->frames[ape->currentframe].pos, SEEK_SET);
00443 
00444     /* Calculate how many blocks there are in this frame */
00445     if (ape->currentframe == (ape->totalframes - 1))
00446         nblocks = ape->finalframeblocks;
00447     else
00448         nblocks = ape->blocksperframe;
00449 
00450     if (av_new_packet(pkt,  ape->frames[ape->currentframe].size + extra_size) < 0)
00451         return AVERROR_NOMEM;
00452 
00453     AV_WL32(pkt->data    , nblocks);
00454     AV_WL32(pkt->data + 4, ape->frames[ape->currentframe].skip);
00455     ret = get_buffer(s->pb, pkt->data + extra_size, ape->frames[ape->currentframe].size);
00456 
00457     pkt->pts = ape->frames[ape->currentframe].pts;
00458     pkt->stream_index = 0;
00459 
00460     /* note: we need to modify the packet size here to handle the last
00461        packet */
00462     pkt->size = ret + extra_size;
00463 
00464     ape->currentframe++;
00465 
00466     return 0;
00467 }
00468 
00469 static int ape_read_close(AVFormatContext * s)
00470 {
00471     APEContext *ape = s->priv_data;
00472 
00473     av_freep(&ape->frames);
00474     av_freep(&ape->seektable);
00475     return 0;
00476 }
00477 
00478 static int ape_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
00479 {
00480     AVStream *st = s->streams[stream_index];
00481     APEContext *ape = s->priv_data;
00482     int index = av_index_search_timestamp(st, timestamp, flags);
00483 
00484     if (index < 0)
00485         return -1;
00486 
00487     ape->currentframe = index;
00488     return 0;
00489 }
00490 
00491 AVInputFormat ape_demuxer = {
00492     "ape",
00493     NULL_IF_CONFIG_SMALL("Monkey's Audio"),
00494     sizeof(APEContext),
00495     ape_probe,
00496     ape_read_header,
00497     ape_read_packet,
00498     ape_read_close,
00499     ape_read_seek,
00500     .extensions = "ape,apl,mac"
00501 };

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