mkvtoolnix/r_ac3.cpp
2003-06-15 14:03:28 +00:00

133 lines
3.0 KiB
C++

/*
mkvmerge -- utility for splicing together matroska files
from component media subtypes
r_ac3.h
Written by Moritz Bunkus <moritz@bunkus.org>
Distributed under the GPL
see the file COPYING for details
or visit http://www.gnu.org/copyleft/gpl.html
*/
/*!
\file
\version $Id$
\brief AC3 demultiplexer module
\author Moritz Bunkus <moritz@bunkus.org>
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
extern "C" {
#include <avilib.h>
}
#include "mkvmerge.h"
#include "common.h"
#include "error.h"
#include "r_ac3.h"
#include "p_ac3.h"
int ac3_reader_c::probe_file(mm_io_c *mm_io, int64_t size) {
char buf[4096];
int pos;
ac3_header_t ac3header;
if (size < 4096)
return 0;
try {
mm_io->setFilePointer(0, seek_beginning);
if (mm_io->read(buf, 4096) != 4096)
return 0;
mm_io->setFilePointer(0, seek_beginning);
} catch (exception &ex) {
return 0;
}
pos = find_ac3_header((unsigned char *)buf, 4096, &ac3header);
if (pos != 0)
return 0;
return 1;
}
ac3_reader_c::ac3_reader_c(track_info_t *nti) throw (error_c):
generic_reader_c(nti) {
int pos;
ac3_header_t ac3header;
try {
mm_io = new mm_io_c(ti->fname, MODE_READ);
mm_io->setFilePointer(0, seek_end);
size = mm_io->getFilePointer();
mm_io->setFilePointer(0, seek_beginning);
chunk = (unsigned char *)safemalloc(4096);
if (mm_io->read(chunk, 4096) != 4096)
throw error_c("ac3_reader: Could not read 4096 bytes.");
mm_io->setFilePointer(0, seek_beginning);
} catch (exception &ex) {
throw error_c("ac3_reader: Could not open the source file.");
}
pos = find_ac3_header(chunk, 4096, &ac3header);
if (pos < 0)
throw error_c("ac3_reader: No valid AC3 packet found in the first "
"4096 bytes.\n");
bytes_processed = 0;
ti->id = 0; // ID for this track.
ac3packetizer = new ac3_packetizer_c(this, ac3header.sample_rate,
ac3header.channels, ti);
if (verbose)
fprintf(stdout, "Using AC3 demultiplexer for %s.\n+-> Using "
"AC3 output module for audio stream.\n", ti->fname);
}
ac3_reader_c::~ac3_reader_c() {
delete mm_io;
if (chunk != NULL)
safefree(chunk);
if (ac3packetizer != NULL)
delete ac3packetizer;
}
int ac3_reader_c::read() {
int nread;
nread = mm_io->read(chunk, 4096);
if (nread <= 0)
return 0;
ac3packetizer->process(chunk, nread);
bytes_processed += nread;
return EMOREDATA;
}
packet_t *ac3_reader_c::get_packet() {
return ac3packetizer->get_packet();
}
int ac3_reader_c::display_priority() {
return DISPLAYPRIORITY_HIGH - 1;
}
void ac3_reader_c::display_progress() {
fprintf(stdout, "progress: %lld/%lld bytes (%d%%)\r",
bytes_processed, size,
(int)(bytes_processed * 100L / size));
fflush(stdout);
}
void ac3_reader_c::set_headers() {
ac3packetizer->set_headers();
}
void ac3_reader_c::identify() {
fprintf(stdout, "File '%s': container: AC3\nTrack ID 0: audio (AC3)\n",
ti->fname);
}