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/*
* Descent 3
* Copyright (C) 2024 Parallax Software
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <cstdint>
#include <cstdio>
#include "aencode.h"
#include "audio_encode.h"
#include "mono.h"
int32_t aenc_ReadSamp(void *data) {
FILE *f = (FILE *)data;
int a, b;
a = getc(f);
if (a == EOF)
return ReadSampleEof;
b = getc(f);
if (b == EOF)
return ReadSampleEof;
return (b << 8) | a;
}
bool aenc_Compress(char *input_filename, char *output_filename, const int *input_levels, const int *input_samples,
const int *input_rate, const int *input_channels, const float *input_factor,
const float *input_volscale) {
FILE *in, *out;
int32_t result;
int levels = 0, samples_per_subband = 0;
unsigned sample_rate = 0, channels = 0;
float factor = 0, volume_scale = 0;
int levels_set = 0, samples_per_subband_set = 0, sample_rate_set = 0, channels_set = 0, factor_set = 0,
volume_scale_set = 0;
in = fopen(input_filename, "rb");
if (!in) {
mprintf(0, "AENC: Unable to open %s for input.\n", input_filename);
return false;
}
if (input_levels) {
levels = *input_levels; // Levels (default 7 or for 2k total)
levels_set = 1;
if (levels < 0 || levels > 16) {
mprintf(0, "AENC: Warning: levels outside of the range 0 to 16\n");
}
}
if (input_samples) {
samples_per_subband = *input_samples; // Samples per subband (default 16 or for 2k total)
samples_per_subband_set = 1;
if (samples_per_subband < 1 || samples_per_subband > 1024) {
mprintf(0, "AENC: Warning: samples per subband not in the range 1 to 1024\n");
}
}
if (input_rate) {
sample_rate = *input_rate; // Sample rate (default 22K)
sample_rate_set = 1;
if (sample_rate != 11025 && sample_rate != 22050 && sample_rate != 44100) {
mprintf(0, "AENC: Warning: sample rate not 11025, 22050, or 44100\n");
}
}
if (input_channels) {
channels = *input_channels;
channels_set = 1;
if (channels != 1 && channels != 2) {
mprintf(0, "AENC: Warning: /C channels not 1 or 2\n");
}
}
if (input_factor) {
factor = *input_factor; // Factor of compression (default 4 for 22K, 8 for 44K)
factor_set = 1;
if (factor != 0.0f && factor < 1.0f)
factor = 1.0f / factor;
if (factor <= 0.0f) {
mprintf(0, "AENC: Warning: compression factor <= 0.0\n");
factor = 1.0f;
}
}
if (input_volscale) {
volume_scale = *input_volscale; // Volume scaling (slightly <= 1.0, default ,97)
volume_scale_set = 1;
}
if (!levels_set && !samples_per_subband_set) {
levels = 7;
samples_per_subband = 16;
} else if (!samples_per_subband_set) {
samples_per_subband = 2048 / (1 << levels);
if (samples_per_subband < 8)
samples_per_subband = 8;
} else if (!levels_set) {
unsigned subbands = (2048 / samples_per_subband) >> 1;
for (levels = 0; subbands; subbands >>= 1, ++levels) {
}
}
if (!sample_rate_set)
sample_rate = 22050;
if (!channels_set)
channels = 1;
if (!factor_set)
factor = sample_rate <= 22050 ? 4.0f : 8.0f;
if (!volume_scale_set)
volume_scale = .97f;
out = fopen(output_filename, "wb");
if (!out) {
mprintf(0, "AENC: Unable to open %s for output.\n", output_filename);
return false;
}
result = AudioEncode(aenc_ReadSamp, in, channels, sample_rate, volume_scale, out, levels, samples_per_subband,
1.0f / factor);
fclose(out);
fclose(in);
return result > 0;
}
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