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/* aKode: Magic
Copyright (C) 2004 Allan Sandfeld Jensen <kde@carewolf.com>
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Library General Public License for more details.
You should have received a copy of the GNU Library General Public License
along with this library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
Boston, MA 02110-1301, USA.
*/
#include <cstring>
#include "akodelib.h"
#include "magic.h"
#include "file.h"
#include <iostream>
using std::cerr;
namespace aKode {
namespace Magic {
static int detectID3v2(File *src)
{
char header[6];
unsigned char *buf = (unsigned char*)header;
if(src->read(header, 4)) {
// skip id3v2 headers
if (memcmp(header, "ID3", 3) == 0) {
src->read(header, 6);
int size = 10;
if (buf[1] & 0x10) size += 10;
if (buf[5] > 127 || buf[4] > 127 || buf[3] > 127 || buf[2] > 127)
{
size += buf[5];
size += buf[4] << 8;
size += buf[3] << 18;
size += buf[2] << 24;
cerr << "Un-unsynchronized size\n";
}
size += buf[5];
size += buf[4] << 7;
size += buf[3] << 14;
size += buf[2] << 21;
// cerr << "ID3v2 header found(size="<< size << ")\n";
return size;
}
}
return 0;
}
/*
struct OggMagic {
char magic[8];
int len;
void *format;
}
OggMagic ogg_magic = {
{"fLaC", 4, &oggflac_format},
{"\x7fFLAC", 5, &oggflac_format},
{"\x01vorbis", 7, &vorbis_format},
{"Speex ", 7, &speex_format}
{"", 0, 0}
}
Format* detectOgg(File *src, int skip) {
Format *res = 0;
char oggmagic[7];
src->seek(skip+28);
src->read(oggmagic, 7);
for (OggMagic *i = ogg_magic; i->len >0; i++) {
if (memcmp(oggmagic, i->magic, i->len) == 0)
return i->format;
}
return res;
} */
string detectRIFF(File *src, int skip) {
string res;
char riffmagic[4];
src->seek(skip+8);
src->read(riffmagic, 4);
if (memcmp(riffmagic, "WAVE",4) == 0) {
char wavmagic[2];
src->seek(skip+20);
src->read(wavmagic, 2);
if (wavmagic[0] == 1)
res = "wav";
else
if (wavmagic[0] == 80)
res = "mpeg";
else
if (wavmagic[0] == 85)
res = "mpeg";
}
return res;
}
string detectMPEG(File *src, int skip) {
string res;
unsigned char mpegheader[2];
src->seek(skip);
src->read((char*)mpegheader, 2);
if (mpegheader[0] == 0xff && (mpegheader[1] & 0xe0) == 0xe0) // frame synchronizer
if((mpegheader[1] & 0x18) != 0x08) // support MPEG 1, 2 and 2.5
if((mpegheader[1] & 0x06) != 0x00) // Layer I, II and III
res = "mpeg";
return res;
}
string detectSuffix(string filename) {
// A lot of mp3s dont start with a synchronization
// so use some suffix matching as well.
int len = filename.length();
if (len < 4) return "";
string end = filename.substr(len-4, 4);
if (end == ".mp3") return "mpeg";
if (end == ".ogg") return "xiph";
if (end == ".wma") return "ffmpeg";
if (end == ".m4a") return "ffmpeg";
if (end == ".aac") return "ffmpeg";
if (end == ".ac3") return "ffmpeg";
return "";
}
string detectFile(File *src) {
string res;
if (!src->openRO())
return res;
int skip = detectID3v2(src);
char magic[4];
src->seek(skip);
src->read(magic, 4);
if (memcmp(magic, "fLaC", 4) == 0)
res = "xiph";
else
if (memcmp(magic, "OggS", 4) == 0)
res = "xiph";
else
if (memcmp(magic, "MP+", 3) == 0)
res = "mpc";
else
if (memcmp(magic, "\x30\x26\xb2\x75", 4) == 0) // ASF
res = "ffmpeg";
else
if (memcmp(magic, ".RMF", 4) == 0) // RealAudio
res = "ffmpeg";
else
if (memcmp(magic, ".ra", 3) == 0) // Old RealAudio
res = "ffmpeg";
else
if (memcmp(magic, "RIFF", 4) == 0)
res = detectRIFF(src, skip);
else
res = detectMPEG(src, skip);
if (res.empty()) res = detectSuffix(src->filename);
src->close();
return res;
}
/*
Format *detectStream(Stream *src) {
Format *res = 0;
if (!src->openRO())
return 0;
// Search for Ogg or MPEG synchronization header
char *page = new char[4096];
src->read(page, 4096);
for (int i=0; i<4096; i++) {
if (page[i] == 'O' && page[i+1] == 'g' && page[i+1] == 'g' && page[i+1] == 'S') {
res = detectOgg(src, i);
if (res) break;
}
if (page[i] == 0xff && (page[i+1] & 0x80) == 0x80) {
res = detectMPEG(src, i);
if (res) break;
}
}
return res;
} */
} // namespace
} // namespace
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