mkvtoolnix/r_mp3.cpp

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2003-02-16 00:05:07 +00:00
/*
ogmmerge -- utility for splicing together ogg bitstreams
from component media subtypes
r_mp3.cpp
MP3 demultiplexer module
Written by Moritz Bunkus <moritz@bunkus.org>
Based on Xiph.org's 'oggmerge' found in their CVS repository
See http://www.xiph.org
Distributed under the GPL
see the file COPYING for details
or visit http://www.gnu.org/copyleft/gpl.html
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <ogg/ogg.h>
#include "ogmmerge.h"
#include "ogmstreams.h"
#include "queue.h"
#include "r_mp3.h"
#include "mp3_common.h"
#ifdef DMALLOC
#include <dmalloc.h>
#endif
int mp3_reader_c::probe_file(FILE *file, u_int64_t size) {
char buf[4096];
int pos;
unsigned long header;
mp3_header_t mp3header;
if (size < 4096)
return 0;
if (fseek(file, 0, SEEK_SET) != 0)
return 0;
if (fread(buf, 1, 4096, file) != 4096) {
fseek(file, 0, SEEK_SET);
return 0;
}
fseek(file, 0, SEEK_SET);
pos = find_mp3_header(buf, 4096, &header);
if (pos < 0)
return 0;
decode_mp3_header(header, &mp3header);
if ((4 - ((header >> 17) & 3)) != 3)
return 0;
pos = find_mp3_header(&buf[pos + mp3header.framesize + 4], 4096 - pos - 4 -
mp3header.framesize, &header);
if (pos < 0)
return 0;
if ((4 - ((header >> 17) & 3)) != 3)
return 0;
return 1;
}
mp3_reader_c::mp3_reader_c(char *fname, audio_sync_t *nasync,
range_t *nrange, char **ncomments) throw (error_c) {
int pos;
unsigned long header;
mp3_header_t mp3header;
if ((file = fopen(fname, "r")) == NULL)
throw error_c("mp3_reader: Could not open source file.");
if (fseek(file, 0, SEEK_END) != 0)
throw error_c("mp3_reader: Could not seek to end of file.");
size = ftell(file);
if (fseek(file, 0, SEEK_SET) != 0)
throw error_c("mp3_reader: Could not seek to beginning of file.");
chunk = (unsigned char *)malloc(4096);
if (chunk == NULL)
die("malloc");
if (fread(chunk, 1, 4096, file) != 4096)
throw error_c("mp3_reader: Could not read 4096 bytes.");
if (fseek(file, 0, SEEK_SET) != 0)
throw error_c("mp3_reader: Could not seek to beginning of file.");
pos = find_mp3_header((char *)chunk, 4096, &header);
if (pos < 0)
throw error_c("mp3_reader: No valid MP3 packet found in the first " \
"4096 bytes.\n");
decode_mp3_header(header, &mp3header);
bytes_processed = 0;
mp3packetizer = new mp3_packetizer_c(mp3_freqs[mp3header.sampling_frequency],
mp3header.stereo ? 2 : 1,
mp3_tabsel[mp3header.lsf]
[mp3header.bitrate_index],
nasync, nrange, ncomments);
if (verbose)
fprintf(stderr, "Using MP3 demultiplexer for %s.\n+-> Using " \
"MP3 output module for audio stream.\n", fname);
}
mp3_reader_c::~mp3_reader_c() {
if (file != NULL)
fclose(file);
if (chunk != NULL)
free(chunk);
if (mp3packetizer != NULL)
delete mp3packetizer;
}
int mp3_reader_c::read() {
int nread, last_frame;
do {
if (mp3packetizer->page_available())
return EMOREDATA;
nread = fread(chunk, 1, 4096, file);
if (nread <= 0) {
mp3packetizer->produce_eos_packet();
return 0;
}
last_frame = (nread == 4096 ? 0 : 1);
mp3packetizer->process((char *)chunk, nread, last_frame);
bytes_processed += nread;
if (last_frame)
return 0;
} while (1);
}
int mp3_reader_c::serial_in_use(int serial) {
return mp3packetizer->serial_in_use(serial);
}
ogmmerge_page_t *mp3_reader_c::get_header_page(int header_type) {
return mp3packetizer->get_header_page(header_type);
}
ogmmerge_page_t *mp3_reader_c::get_page() {
return mp3packetizer->get_page();
}
void mp3_reader_c::reset() {
if (mp3packetizer != NULL)
mp3packetizer->reset();
}
int mp3_reader_c::display_priority() {
return DISPLAYPRIORITY_HIGH - 1;
}
void mp3_reader_c::display_progress() {
fprintf(stdout, "progress: %lld/%lld bytes (%d%%)\r",
bytes_processed, size,
(int)(bytes_processed * 100L / size));
fflush(stdout);
}