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 if (!ape->seektable)
00360 return AVERROR(ENOMEM);
00361 for (i = 0; i < ape->seektablelength / sizeof(uint32_t); i++)
00362 ape->seektable[i] = get_le32(pb);
00363 }
00364 
00365 ape->frames[0].pos = ape->firstframe;
00366 ape->frames[0].nblocks = ape->blocksperframe;
00367 ape->frames[0].skip = 0;
00368 for (i = 1; i < ape->totalframes; i++) {
00369 ape->frames[i].pos = ape->seektable[i]; //ape->frames[i-1].pos + ape->blocksperframe;
00370 ape->frames[i].nblocks = ape->blocksperframe;
00371 ape->frames[i - 1].size = ape->frames[i].pos - ape->frames[i - 1].pos;
00372 ape->frames[i].skip = (ape->frames[i].pos - ape->frames[0].pos) & 3;
00373 }
00374 ape->frames[ape->totalframes - 1].size = ape->finalframeblocks * 4;
00375 ape->frames[ape->totalframes - 1].nblocks = ape->finalframeblocks;
00376 
00377 for (i = 0; i < ape->totalframes; i++) {
00378 if(ape->frames[i].skip){
00379 ape->frames[i].pos -= ape->frames[i].skip;
00380 ape->frames[i].size += ape->frames[i].skip;
00381 }
00382 ape->frames[i].size = (ape->frames[i].size + 3) & ~3;
00383 }
00384 
00385 
00386 ape_dumpinfo(s, ape);
00387 
00388 /* try to read APE tags */
00389 if (!url_is_streamed(pb)) {
00390 ape_parse_tag(s);
00391 url_fseek(pb, 0, SEEK_SET);
00392 }
00393 
00394 av_log(s, AV_LOG_DEBUG, "Decoding file - v%d.%02d, compression level %d\n", ape->fileversion / 1000, (ape->fileversion % 1000) / 10, ape->compressiontype);
00395 
00396 /* now we are ready: build format streams */
00397 st = av_new_stream(s, 0);
00398 if (!st)
00399 return -1;
00400 
00401 total_blocks = (ape->totalframes == 0) ? 0 : ((ape->totalframes - 1) * ape->blocksperframe) + ape->finalframeblocks;
00402 
00403 st->codec->codec_type = CODEC_TYPE_AUDIO;
00404 st->codec->codec_id = CODEC_ID_APE;
00405 st->codec->codec_tag = MKTAG('A', 'P', 'E', ' ');
00406 st->codec->channels = ape->channels;
00407 st->codec->sample_rate = ape->samplerate;
00408 st->codec->bits_per_coded_sample = ape->bps;
00409 st->codec->frame_size = MAC_SUBFRAME_SIZE;
00410 
00411 st->nb_frames = ape->totalframes;
00412 s->start_time = 0;
00413 s->duration = (int64_t) total_blocks * AV_TIME_BASE / ape->samplerate;
00414 av_set_pts_info(st, 64, MAC_SUBFRAME_SIZE, ape->samplerate);
00415 
00416 st->codec->extradata = av_malloc(APE_EXTRADATA_SIZE);
00417 st->codec->extradata_size = APE_EXTRADATA_SIZE;
00418 AV_WL16(st->codec->extradata + 0, ape->fileversion);
00419 AV_WL16(st->codec->extradata + 2, ape->compressiontype);
00420 AV_WL16(st->codec->extradata + 4, ape->formatflags);
00421 
00422 pts = 0;
00423 for (i = 0; i < ape->totalframes; i++) {
00424 ape->frames[i].pts = pts;
00425 av_add_index_entry(st, ape->frames[i].pos, ape->frames[i].pts, 0, 0, AVINDEX_KEYFRAME);
00426 pts += ape->blocksperframe / MAC_SUBFRAME_SIZE;
00427 }
00428 
00429 return 0;
00430 }
00431 
00432 static int ape_read_packet(AVFormatContext * s, AVPacket * pkt)
00433 {
00434 int ret;
00435 int nblocks;
00436 APEContext *ape = s->priv_data;
00437 uint32_t extra_size = 8;
00438 
00439 if (url_feof(s->pb))
00440 return AVERROR_IO;
00441 if (ape->currentframe > ape->totalframes)
00442 return AVERROR_IO;
00443 
00444 url_fseek (s->pb, ape->frames[ape->currentframe].pos, SEEK_SET);
00445 
00446 /* Calculate how many blocks there are in this frame */
00447 if (ape->currentframe == (ape->totalframes - 1))
00448 nblocks = ape->finalframeblocks;
00449 else
00450 nblocks = ape->blocksperframe;
00451 
00452 if (av_new_packet(pkt, ape->frames[ape->currentframe].size + extra_size) < 0)
00453 return AVERROR_NOMEM;
00454 
00455 AV_WL32(pkt->data , nblocks);
00456 AV_WL32(pkt->data + 4, ape->frames[ape->currentframe].skip);
00457 ret = get_buffer(s->pb, pkt->data + extra_size, ape->frames[ape->currentframe].size);
00458 
00459 pkt->pts = ape->frames[ape->currentframe].pts;
00460 pkt->stream_index = 0;
00461 
00462 /* note: we need to modify the packet size here to handle the last
00463  packet */
00464 pkt->size = ret + extra_size;
00465 
00466 ape->currentframe++;
00467 
00468 return 0;
00469 }
00470 
00471 static int ape_read_close(AVFormatContext * s)
00472 {
00473 APEContext *ape = s->priv_data;
00474 
00475 av_freep(&ape->frames);
00476 av_freep(&ape->seektable);
00477 return 0;
00478 }
00479 
00480 static int ape_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
00481 {
00482 AVStream *st = s->streams[stream_index];
00483 APEContext *ape = s->priv_data;
00484 int index = av_index_search_timestamp(st, timestamp, flags);
00485 
00486 if (index < 0)
00487 return -1;
00488 
00489 ape->currentframe = index;
00490 return 0;
00491 }
00492 
00493 AVInputFormat ape_demuxer = {
00494 "ape",
00495 NULL_IF_CONFIG_SMALL("Monkey's Audio"),
00496 sizeof(APEContext),
00497 ape_probe,
00498 ape_read_header,
00499 ape_read_packet,
00500 ape_read_close,
00501 ape_read_seek,
00502 .extensions = "ape,apl,mac"
00503 };

Generated on Fri Oct 26 02:35:40 2012 for FFmpeg by doxygen 1.5.8

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