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mirror of https://github.com/cookiengineer/audacity synced 2025-06-17 00:20:06 +02:00
2010-01-24 09:19:39 +00:00

240 lines
6.9 KiB
C

/*
* TwoLAME: an optimized MPEG Audio Layer Two encoder
*
* Copyright (C) 2001-2004 Michael Cheng
* Copyright (C) 2004-2006 The TwoLAME Project
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* $Id: util.c,v 1.3 2008-02-01 19:44:36 richardash1981 Exp $
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <assert.h>
#include "twolame.h"
#include "common.h"
#include "util.h"
// Return string containg version number
// of this library
const char* get_twolame_version( void )
{
const char* str = PACKAGE_VERSION;
return str;
}
// Return string containg version number
// of this library
const char* get_twolame_url( void )
{
const char* str = "http://www.twolame.org";
return str;
}
/* 1: MPEG-1, 0: MPEG-2 LSF, 1995-07-11 shn */
static const int bitrate_table[2][15] = {
{0, 8, 16, 24, 32, 40, 48, 56, 64, 80, 96, 112, 128, 144, 160},
{0, 32, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320, 384}
};
//
// Returns a name string for MPEG version enumeration
//
const char* twolame_mpeg_version_name (int version)
{
static const char *version_name[3] = { "MPEG-2 LSF", "MPEG-1", "Illegal Version" };
if (version==0)
return(version_name[0]);
if (version==1)
return(version_name[1]);
return(version_name[2]);
}
// Returns the index associated with a bitrate for
// the specified version of MPEG.
//
// Returns -1 for invalid bitrates
//
int twolame_get_bitrate_index(int bitrate, TWOLAME_MPEG_version version)
{
int index = 0;
int found = 0;
// MFC sanity check.
if (version!=0 && version!=1) {
fprintf(stderr,"twolame_get_bitrate_index: invalid version index %i\n",version);
return -1;
}
while (!found && index < 15) {
if (bitrate_table[version][index] == bitrate)
found = 1;
else
++index;
}
if (found) return (index);
else {
fprintf (stderr,
"twolame_get_bitrate_index: %d is not a legal bitrate for version '%s'\n",
bitrate, twolame_mpeg_version_name(version));
return -1;
}
}
// convert samp frq in Hz to index
// legal rates 16000, 22050, 24000, 32000, 44100, 48000
// -1 is returned for invalid samplerates
int twolame_get_samplerate_index (long sample_rate)
{
switch (sample_rate) {
case 44100L: return 0;
case 48000L: return 1;
case 32000L: return 2;
case 22050L: return 0;
case 24000L: return 1;
case 16000L: return 2;
}
// Invalid choice of samplerate
fprintf (stderr, "twolame_get_samplerate_index: %ld is not a legal sample rate\n", sample_rate);
return -1;
}
// Return the MPEG Version to use for the specified samplerate
// -1 is returned for invalid samplerates
int twolame_get_version_for_samplerate (long sample_rate)
{
switch (sample_rate) {
case 48000L: return TWOLAME_MPEG1;
case 44100L: return TWOLAME_MPEG1;
case 32000L: return TWOLAME_MPEG1;
case 24000L: return TWOLAME_MPEG2;
case 22050L: return TWOLAME_MPEG2;
case 16000L: return TWOLAME_MPEG2;
}
// Invalid choice of samplerate
fprintf (stderr, "twolame_get_version_for_samplerate: %ld is not a legal sample rate\n", sample_rate);
return -1;
}
// Get the number of bytes per frame, for current settings
int twolame_get_framelength( twolame_options *glopts )
{
int bytes = 144 * (glopts->bitrate*1000) / glopts->samplerate_out;
if (glopts->padding)
bytes++;
return bytes;
}
// Print the library version and
// encoder parameter settings to STDERR
void twolame_print_config(twolame_options *glopts)
{
FILE* fd = stderr;
// Are we being silent ?
if (glopts->verbosity<=0) return;
// Are we being brief ?
if (glopts->verbosity==1) {
fprintf(fd, "LibTwoLame version %s (%s)\n", get_twolame_version(), get_twolame_url());
fprintf (fd, "Encoding as %dHz, ", twolame_get_out_samplerate(glopts));
fprintf (fd, "%d kbps, ", twolame_get_bitrate(glopts) );
if (twolame_get_VBR(glopts)) fprintf (fd, "VBR, " );
else fprintf (fd, "CBR, " );
fprintf (fd, "%s Layer II\n", twolame_get_version_name(glopts));
} else {
fprintf (fd, "---------------------------------------------------------\n");
fprintf (fd, "LibTwoLame %s (%s)\n", get_twolame_version(), get_twolame_url());
fprintf (fd, "Input : %d Hz, %d channels\n",
twolame_get_in_samplerate(glopts),
twolame_get_num_channels(glopts));
fprintf (fd, "Output: %d Hz, %s\n",
twolame_get_out_samplerate(glopts),
twolame_get_mode_name(glopts));
fprintf (fd, "%d kbps ", twolame_get_bitrate(glopts) );
if (twolame_get_VBR(glopts)) fprintf (fd, "VBR " );
else fprintf (fd, "CBR " );
fprintf (fd, "%s Layer II ", twolame_get_version_name(glopts));
fprintf (fd, "psycho model=%d \n", twolame_get_psymodel(glopts));
fprintf (fd, "[De-emph:%s Copyright:%s Original:%s]\n",
((twolame_get_emphasis(glopts)) ? "On " : "Off"),
((twolame_get_copyright(glopts)) ? "Yes" : "No "),
((twolame_get_original(glopts)) ? "Yes" : "No "));
fprintf (fd, "[Padding:%s CRC:%s Energy:%s ]\n",
((twolame_get_padding(glopts)) ? "Normal" : "Off "),
((twolame_get_error_protection(glopts)) ? "On " : "Off"),
((twolame_get_energy_levels(glopts)) ? "On " : "Off"));
if (glopts->verbosity>=3) {
if (twolame_get_VBR(glopts)) {
fprintf (fd, " - VBR Enabled. Using MNR boost of %f\n", twolame_get_VBR_level(glopts));
fprintf (fd, " - VBR bitrate index limits [%i -> %i]\n", glopts->lower_index, glopts->upper_index);
}
fprintf(fd," - ATH adjustment %f\n", twolame_get_ATH_level(glopts));
if (twolame_get_num_ancillary_bits(glopts))
fprintf(fd," - Reserving %i ancillary bits\n", twolame_get_num_ancillary_bits(glopts));
if (twolame_get_scale(glopts)!=1.0f)
fprintf(fd," - Scaling audio by %f\n", twolame_get_scale(glopts));
if (twolame_get_scale_left(glopts)!=1.0f)
fprintf(fd," - Scaling left channel by %f\n", twolame_get_scale_left(glopts));
if (twolame_get_scale_right(glopts)!=1.0f)
fprintf(fd," - Scaling right channel by %f\n", twolame_get_scale_right(glopts));
//if (glopts->num_channels_in == 2 && glopts->num_channels_out == 1 ) {
// fprintf(fd, " - Downmixing from stereo to mono.\n");
//} else if (glopts->num_channels_in == 1 && glopts->num_channels_out == 2 ) {
// fprintf(fd, " - Upmixing from mono to stereo.\n");
//}
}
fprintf (fd, "---------------------------------------------------------\n");
}
}
// vim:ts=4:sw=4:nowrap: