mirror of
https://github.com/curioustorvald/tsvm.git
synced 2026-03-07 11:51:49 +09:00
655 lines
23 KiB
C
655 lines
23 KiB
C
// Created by CuriousTorvald and Claude on 2025-10-23.
|
||
// TAD (Terrarum Advanced Audio) Decoder - Reconstructs audio from TAD format
|
||
|
||
#include <stdio.h>
|
||
#include <stdlib.h>
|
||
#include <stdint.h>
|
||
#include <string.h>
|
||
#include <math.h>
|
||
#include <zstd.h>
|
||
#include <getopt.h>
|
||
|
||
#define DECODER_VENDOR_STRING "Decoder-TAD 20251026"
|
||
|
||
// TAD format constants (must match encoder)
|
||
#undef TAD32_COEFF_SCALARS
|
||
|
||
// Coefficient scalars for each subband (CDF 9/7 with 9 decomposition levels)
|
||
// Index 0 = LL band, Index 1-9 = H bands (L9 to L1)
|
||
static const float TAD32_COEFF_SCALARS[] = {64.0f, 45.255f, 32.0f, 22.627f, 16.0f, 11.314f, 8.0f, 5.657f, 4.0f, 2.828f};
|
||
|
||
#define TAD_DEFAULT_CHUNK_SIZE 32768
|
||
#define TAD_MIN_CHUNK_SIZE 1024
|
||
#define TAD_SAMPLE_RATE 32000
|
||
#define TAD_CHANNELS 2
|
||
|
||
// Significance map methods
|
||
#define TAD_SIGMAP_1BIT 0
|
||
#define TAD_SIGMAP_2BIT 1
|
||
#define TAD_SIGMAP_RLE 2
|
||
|
||
// Quality levels
|
||
#define TAD_QUALITY_MIN 0
|
||
#define TAD_QUALITY_MAX 5
|
||
|
||
static inline float FCLAMP(float x, float min, float max) {
|
||
return x < min ? min : (x > max ? max : x);
|
||
}
|
||
|
||
// Calculate DWT levels from chunk size (must be power of 2, >= 1024)
|
||
static int calculate_dwt_levels(int chunk_size) {
|
||
/*if (chunk_size < TAD_MIN_CHUNK_SIZE) {
|
||
fprintf(stderr, "Error: Chunk size %d is below minimum %d\n", chunk_size, TAD_MIN_CHUNK_SIZE);
|
||
return -1;
|
||
}
|
||
|
||
// Calculate levels: log2(chunk_size) - 1
|
||
int levels = 0;
|
||
int size = chunk_size;
|
||
while (size > 1) {
|
||
size >>= 1;
|
||
levels++;
|
||
}
|
||
return levels - 2;*/
|
||
return 9;
|
||
}
|
||
|
||
//=============================================================================
|
||
// Haar DWT Implementation (inverse only needed for decoder)
|
||
//=============================================================================
|
||
|
||
static void dwt_haar_inverse_1d(float *data, int length) {
|
||
if (length < 2) return;
|
||
|
||
float *temp = malloc(length * sizeof(float));
|
||
int half = (length + 1) / 2;
|
||
|
||
for (int i = 0; i < half; i++) {
|
||
if (2 * i + 1 < length) {
|
||
temp[2 * i] = data[i] + data[half + i];
|
||
temp[2 * i + 1] = data[i] - data[half + i];
|
||
} else {
|
||
temp[2 * i] = data[i];
|
||
}
|
||
}
|
||
|
||
memcpy(data, temp, length * sizeof(float));
|
||
free(temp);
|
||
}
|
||
|
||
// 9/7 inverse DWT (from TSVM Kotlin code)
|
||
static void dwt_97_inverse_1d(float *data, int length) {
|
||
if (length < 2) return;
|
||
|
||
float *temp = malloc(length * sizeof(float));
|
||
int half = (length + 1) / 2;
|
||
|
||
// Split into low and high frequency components (matching TSVM layout)
|
||
for (int i = 0; i < half; i++) {
|
||
temp[i] = data[i]; // Low-pass coefficients (first half)
|
||
}
|
||
for (int i = 0; i < length / 2; i++) {
|
||
if (half + i < length) {
|
||
temp[half + i] = data[half + i]; // High-pass coefficients (second half)
|
||
}
|
||
}
|
||
|
||
// 9/7 inverse lifting coefficients from TSVM
|
||
const float alpha = -1.586134342f;
|
||
const float beta = -0.052980118f;
|
||
const float gamma = 0.882911076f;
|
||
const float delta = 0.443506852f;
|
||
const float K = 1.230174105f;
|
||
|
||
// Step 1: Undo scaling
|
||
for (int i = 0; i < half; i++) {
|
||
temp[i] /= K; // Low-pass coefficients
|
||
}
|
||
for (int i = 0; i < length / 2; i++) {
|
||
if (half + i < length) {
|
||
temp[half + i] *= K; // High-pass coefficients
|
||
}
|
||
}
|
||
|
||
// Step 2: Undo δ update
|
||
for (int i = 0; i < half; i++) {
|
||
float d_curr = (half + i < length) ? temp[half + i] : 0.0f;
|
||
float d_prev = (i > 0 && half + i - 1 < length) ? temp[half + i - 1] : d_curr;
|
||
temp[i] -= delta * (d_curr + d_prev);
|
||
}
|
||
|
||
// Step 3: Undo γ predict
|
||
for (int i = 0; i < length / 2; i++) {
|
||
if (half + i < length) {
|
||
float s_curr = temp[i];
|
||
float s_next = (i + 1 < half) ? temp[i + 1] : s_curr;
|
||
temp[half + i] -= gamma * (s_curr + s_next);
|
||
}
|
||
}
|
||
|
||
// Step 4: Undo β update
|
||
for (int i = 0; i < half; i++) {
|
||
float d_curr = (half + i < length) ? temp[half + i] : 0.0f;
|
||
float d_prev = (i > 0 && half + i - 1 < length) ? temp[half + i - 1] : d_curr;
|
||
temp[i] -= beta * (d_curr + d_prev);
|
||
}
|
||
|
||
// Step 5: Undo α predict
|
||
for (int i = 0; i < length / 2; i++) {
|
||
if (half + i < length) {
|
||
float s_curr = temp[i];
|
||
float s_next = (i + 1 < half) ? temp[i + 1] : s_curr;
|
||
temp[half + i] -= alpha * (s_curr + s_next);
|
||
}
|
||
}
|
||
|
||
// Reconstruction - interleave low and high pass
|
||
for (int i = 0; i < length; i++) {
|
||
if (i % 2 == 0) {
|
||
// Even positions: low-pass coefficients
|
||
data[i] = temp[i / 2];
|
||
} else {
|
||
// Odd positions: high-pass coefficients
|
||
int idx = i / 2;
|
||
if (half + idx < length) {
|
||
data[i] = temp[half + idx];
|
||
} else {
|
||
data[i] = 0.0f;
|
||
}
|
||
}
|
||
}
|
||
|
||
free(temp);
|
||
}
|
||
|
||
// Inverse 1D transform of Four-point interpolating Deslauriers-Dubuc (DD-4)
|
||
static void dwt_dd4_inverse_1d(float *data, int length) {
|
||
if (length < 2) return;
|
||
|
||
float *temp = malloc(length * sizeof(float));
|
||
int half = (length + 1) / 2;
|
||
|
||
// Split into low (even) and high (odd) parts
|
||
for (int i = 0; i < half; i++) {
|
||
temp[i] = data[i]; // Even (low-pass)
|
||
}
|
||
for (int i = 0; i < length / 2; i++) {
|
||
temp[half + i] = data[half + i]; // Odd (high-pass)
|
||
}
|
||
|
||
// Undo update step: s[i] -= 0.25 * (d[i-1] + d[i])
|
||
for (int i = 0; i < half; i++) {
|
||
float d_curr = (i < length / 2) ? temp[half + i] : 0.0f;
|
||
float d_prev = (i > 0 && i - 1 < length / 2) ? temp[half + i - 1] : 0.0f;
|
||
temp[i] -= 0.25f * (d_prev + d_curr);
|
||
}
|
||
|
||
// Undo prediction step: d[i] += P(s[i-1], s[i], s[i+1], s[i+2])
|
||
for (int i = 0; i < length / 2; i++) {
|
||
float s_m1, s_0, s_1, s_2;
|
||
|
||
if (i > 0) s_m1 = temp[i - 1];
|
||
else s_m1 = temp[0]; // mirror boundary
|
||
|
||
s_0 = temp[i];
|
||
|
||
if (i + 1 < half) s_1 = temp[i + 1];
|
||
else s_1 = temp[half - 1];
|
||
|
||
if (i + 2 < half) s_2 = temp[i + 2];
|
||
else if (half > 1) s_2 = temp[half - 2];
|
||
else s_2 = temp[half - 1];
|
||
|
||
float prediction = (-1.0f/16.0f)*s_m1 + (9.0f/16.0f)*s_0 +
|
||
(9.0f/16.0f)*s_1 + (-1.0f/16.0f)*s_2;
|
||
|
||
temp[half + i] += prediction;
|
||
}
|
||
|
||
// Merge evens and odds back into the original order
|
||
for (int i = 0; i < half; i++) {
|
||
data[2 * i] = temp[i];
|
||
if (2 * i + 1 < length)
|
||
data[2 * i + 1] = temp[half + i];
|
||
}
|
||
|
||
free(temp);
|
||
}
|
||
|
||
static void dwt_haar_inverse_multilevel(float *data, int length, int levels) {
|
||
// Calculate the length at the deepest level (size of low-pass after all forward DWTs)
|
||
int current_length = length;
|
||
for (int level = 0; level < levels; level++) {
|
||
current_length = (current_length + 1) / 2;
|
||
}
|
||
// For 8 levels on 32768: 32768→16384→8192→4096→2048→1024→512→256→128
|
||
|
||
// Inverse transform: double size FIRST, then apply inverse DWT
|
||
// Level 8 inverse: 128 low + 128 high → 256 reconstructed
|
||
// Level 7 inverse: 256 reconstructed + 256 high → 512 reconstructed
|
||
// ... Level 1 inverse: 16384 reconstructed + 16384 high → 32768 reconstructed
|
||
for (int level = levels - 1; level >= 0; level--) {
|
||
current_length *= 2; // MULTIPLY FIRST: 128→256, 256→512, ..., 16384→32768
|
||
if (current_length > length) current_length = length;
|
||
// dwt_haar_inverse_1d(data, current_length); // THEN apply inverse
|
||
// dwt_dd4_inverse_1d(data, current_length); // THEN apply inverse
|
||
dwt_97_inverse_1d(data, current_length); // THEN apply inverse
|
||
}
|
||
}
|
||
|
||
//=============================================================================
|
||
// M/S Stereo Correlation (inverse of decorrelation)
|
||
//=============================================================================
|
||
|
||
// Uniform random in [0, 1)
|
||
static inline float frand01(void) {
|
||
return (float)rand() / ((float)RAND_MAX + 1.0f);
|
||
}
|
||
|
||
// TPDF noise in [-1, +1)
|
||
static inline float tpdf1(void) {
|
||
return (frand01() - frand01());
|
||
}
|
||
|
||
static void ms_correlate(const float *mid, const float *side, float *left, float *right, size_t count) {
|
||
for (size_t i = 0; i < count; i++) {
|
||
// Decode M/S → L/R
|
||
float m = mid[i];
|
||
float s = side[i];
|
||
left[i] = FCLAMP((m + s) * 1.7321f, -1.0f, 1.0f);
|
||
right[i] = FCLAMP((m - s) * 1.7321f, -1.0f, 1.0f);
|
||
}
|
||
}
|
||
|
||
static float signum(float x) {
|
||
if (x > 0.0f) return 1.0f;
|
||
if (x < 0.0f) return -1.0f;
|
||
return 0.0f;
|
||
}
|
||
|
||
static void expand_gamma(float *left, float *right, size_t count) {
|
||
for (size_t i = 0; i < count; i++) {
|
||
// decode(y) = sign(y) * |y|^(1/γ) where γ=0.5
|
||
float x = left[i]; float a = fabsf(x);
|
||
left[i] = signum(x) * a * a;
|
||
float y = right[i]; float b = fabsf(y);
|
||
right[i] = signum(y) * b * b;
|
||
}
|
||
}
|
||
|
||
static void pcm32f_to_pcm8(const float *fleft, const float *fright, uint8_t *left, uint8_t *right, size_t count, float dither_error[2][2]) {
|
||
const float b1 = 1.5f; // 1st feedback coefficient
|
||
const float b2 = -0.75f; // 2nd feedback coefficient
|
||
const float scale = 127.5f;
|
||
const float bias = 128.0f;
|
||
|
||
for (size_t i = 0; i < count; i++) {
|
||
// --- LEFT channel ---
|
||
float feedbackL = b1 * dither_error[0][0] + b2 * dither_error[0][1];
|
||
float ditherL = 0.5f * tpdf1(); // ±0.5 LSB TPDF
|
||
float shapedL = fleft[i] + feedbackL + ditherL / scale;
|
||
shapedL = FCLAMP(shapedL, -1.0f, 1.0f);
|
||
|
||
int qL = (int)lrintf(shapedL * scale);
|
||
if (qL < -128) qL = -128;
|
||
else if (qL > 127) qL = 127;
|
||
left[i] = (uint8_t)(qL + bias);
|
||
|
||
float qerrL = shapedL - (float)qL / scale;
|
||
dither_error[0][1] = dither_error[0][0]; // shift history
|
||
dither_error[0][0] = qerrL;
|
||
|
||
// --- RIGHT channel ---
|
||
float feedbackR = b1 * dither_error[1][0] + b2 * dither_error[1][1];
|
||
float ditherR = 0.5f * tpdf1();
|
||
float shapedR = fright[i] + feedbackR + ditherR / scale;
|
||
shapedR = FCLAMP(shapedR, -1.0f, 1.0f);
|
||
|
||
int qR = (int)lrintf(shapedR * scale);
|
||
if (qR < -128) qR = -128;
|
||
else if (qR > 127) qR = 127;
|
||
right[i] = (uint8_t)(qR + bias);
|
||
|
||
float qerrR = shapedR - (float)qR / scale;
|
||
dither_error[1][1] = dither_error[1][0];
|
||
dither_error[1][0] = qerrR;
|
||
}
|
||
}
|
||
|
||
//=============================================================================
|
||
// Dequantization (inverse of quantization)
|
||
//=============================================================================
|
||
|
||
static void get_quantization_weights(int quality, int dwt_levels, float *weights) {
|
||
const float base_weights[16][16] = {
|
||
/* 0*/{1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f},
|
||
/* 1*/{1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f},
|
||
/* 2*/{1.0f, 1.0f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/* 3*/{0.2f, 1.0f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/* 4*/{0.2f, 0.8f, 1.0f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/* 5*/{0.2f, 0.8f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/* 6*/{0.2f, 0.2f, 0.8f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/* 7*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/* 8*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/* 9*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/*10*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/*11*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/*12*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/*13*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f, 1.5f},
|
||
/*14*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f, 1.5f},
|
||
/*15*/{0.2f, 0.2f, 0.8f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.0f, 1.25f, 1.5f, 1.5f}
|
||
};
|
||
|
||
float quality_scale = 1.0f * (1.0f + FCLAMP((5 - quality) * 0.5f, 0.0f, 1000.0f));
|
||
|
||
for (int i = 0; i < dwt_levels; i++) {
|
||
weights[i] = 1.0f;//base_weights[dwt_levels][i] * quality_scale;
|
||
}
|
||
}
|
||
|
||
#define QUANT_STEPS 8.0f // 64 -> [-64..64] -> 7 bits for LL
|
||
|
||
static void dequantize_dwt_coefficients(const int16_t *quantized, float *coeffs, size_t count, int quality, int chunk_size, int dwt_levels) {
|
||
float weights[16];
|
||
get_quantization_weights(quality, dwt_levels, weights);
|
||
|
||
// Calculate sideband boundaries dynamically
|
||
int first_band_size = chunk_size >> dwt_levels;
|
||
|
||
int *sideband_starts = malloc((dwt_levels + 2) * sizeof(int));
|
||
sideband_starts[0] = 0;
|
||
sideband_starts[1] = first_band_size;
|
||
for (int i = 2; i <= dwt_levels + 1; i++) {
|
||
sideband_starts[i] = sideband_starts[i-1] + (first_band_size << (i-2));
|
||
}
|
||
|
||
for (size_t i = 0; i < count; i++) {
|
||
int sideband = dwt_levels;
|
||
for (int s = 0; s <= dwt_levels; s++) {
|
||
if (i < sideband_starts[s + 1]) {
|
||
sideband = s;
|
||
break;
|
||
}
|
||
}
|
||
|
||
// Map (dwt_levels+1) sidebands to dwt_levels weights
|
||
int weight_idx = (sideband == 0) ? 0 : sideband - 1;
|
||
if (weight_idx >= dwt_levels) weight_idx = dwt_levels - 1;
|
||
|
||
float weight = weights[weight_idx];
|
||
coeffs[i] = ((float)quantized[i] * TAD32_COEFF_SCALARS[sideband]) / (QUANT_STEPS * weight);
|
||
}
|
||
|
||
free(sideband_starts);
|
||
}
|
||
|
||
//=============================================================================
|
||
// Significance Map Decoding
|
||
//=============================================================================
|
||
|
||
static size_t decode_sigmap_2bit(const uint8_t *input, int16_t *values, size_t count) {
|
||
size_t map_bytes = (count * 2 + 7) / 8;
|
||
const uint8_t *map = input;
|
||
const uint8_t *read_ptr = input + map_bytes;
|
||
|
||
const int16_t *value_ptr = (const int16_t*)read_ptr;
|
||
uint32_t other_idx = 0;
|
||
|
||
for (size_t i = 0; i < count; i++) {
|
||
size_t bit_pos = i * 2;
|
||
size_t byte_idx = bit_pos / 8;
|
||
size_t bit_offset = bit_pos % 8;
|
||
|
||
uint8_t code = (map[byte_idx] >> bit_offset) & 0x03;
|
||
|
||
// Handle bit spillover
|
||
if (bit_offset == 7) {
|
||
code = (map[byte_idx] >> 7) | ((map[byte_idx + 1] & 0x01) << 1);
|
||
}
|
||
|
||
switch (code) {
|
||
case 0: values[i] = 0; break;
|
||
case 1: values[i] = 1; break;
|
||
case 2: values[i] = -1; break;
|
||
case 3: values[i] = value_ptr[other_idx++]; break;
|
||
}
|
||
}
|
||
|
||
return map_bytes + other_idx * sizeof(int16_t);
|
||
}
|
||
|
||
//=============================================================================
|
||
// Chunk Decoding
|
||
//=============================================================================
|
||
|
||
static int decode_chunk(const uint8_t *input, size_t input_size, uint8_t *pcmu8_stereo,
|
||
int quality, size_t *bytes_consumed, size_t *samples_decoded) {
|
||
const uint8_t *read_ptr = input;
|
||
|
||
// Read chunk header
|
||
uint16_t sample_count = *((const uint16_t*)read_ptr);
|
||
read_ptr += sizeof(uint16_t);
|
||
uint32_t payload_size = *((const uint32_t*)read_ptr);
|
||
read_ptr += sizeof(uint32_t);
|
||
|
||
// Calculate DWT levels from sample count
|
||
int dwt_levels = calculate_dwt_levels(sample_count);
|
||
if (dwt_levels < 0) {
|
||
fprintf(stderr, "Error: Invalid sample count %u\n", sample_count);
|
||
return -1;
|
||
}
|
||
|
||
// Decompress if needed
|
||
const uint8_t *payload;
|
||
uint8_t *decompressed = NULL;
|
||
|
||
// Estimate decompressed size (generous upper bound)
|
||
size_t decompressed_size = sample_count * 4 * sizeof(int16_t);
|
||
decompressed = malloc(decompressed_size);
|
||
|
||
size_t actual_size = ZSTD_decompress(decompressed, decompressed_size, read_ptr, payload_size);
|
||
|
||
if (ZSTD_isError(actual_size)) {
|
||
fprintf(stderr, "Error: Zstd decompression failed: %s\n", ZSTD_getErrorName(actual_size));
|
||
free(decompressed);
|
||
return -1;
|
||
}
|
||
|
||
payload = decompressed;
|
||
|
||
read_ptr += payload_size;
|
||
*bytes_consumed = read_ptr - input;
|
||
*samples_decoded = sample_count;
|
||
|
||
// Allocate working buffers
|
||
int16_t *quant_mid = malloc(sample_count * sizeof(int16_t));
|
||
int16_t *quant_side = malloc(sample_count * sizeof(int16_t));
|
||
float *dwt_mid = malloc(sample_count * sizeof(float));
|
||
float *dwt_side = malloc(sample_count * sizeof(float));
|
||
float *pcm32_left = malloc(sample_count * sizeof(float));
|
||
float *pcm32_right = malloc(sample_count * sizeof(float));
|
||
uint8_t *pcm8_left = malloc(sample_count * sizeof(uint8_t));
|
||
uint8_t *pcm8_right = malloc(sample_count * sizeof(uint8_t));
|
||
|
||
// Decode significance maps
|
||
const uint8_t *payload_ptr = payload;
|
||
size_t mid_bytes, side_bytes;
|
||
|
||
mid_bytes = decode_sigmap_2bit(payload_ptr, quant_mid, sample_count);
|
||
side_bytes = decode_sigmap_2bit(payload_ptr + mid_bytes, quant_side, sample_count);
|
||
|
||
// Dequantize
|
||
dequantize_dwt_coefficients(quant_mid, dwt_mid, sample_count, quality, sample_count, dwt_levels);
|
||
dequantize_dwt_coefficients(quant_side, dwt_side, sample_count, quality, sample_count, dwt_levels);
|
||
|
||
// Inverse DWT
|
||
dwt_haar_inverse_multilevel(dwt_mid, sample_count, dwt_levels);
|
||
dwt_haar_inverse_multilevel(dwt_side, sample_count, dwt_levels);
|
||
|
||
float err[2][2] = {{0,0},{0,0}};
|
||
|
||
// M/S to L/R correlation
|
||
ms_correlate(dwt_mid, dwt_side, pcm32_left, pcm32_right, sample_count);
|
||
|
||
// expand dynamic range
|
||
// expand_gamma(pcm32_left, pcm32_right, sample_count);
|
||
|
||
// dither to 8-bit
|
||
pcm32f_to_pcm8(pcm32_left, pcm32_right, pcm8_left, pcm8_right, sample_count, err);
|
||
|
||
// Interleave stereo output (PCMu8)
|
||
for (size_t i = 0; i < sample_count; i++) {
|
||
pcmu8_stereo[i * 2] = pcm8_left[i];
|
||
pcmu8_stereo[i * 2 + 1] = pcm8_right[i];
|
||
}
|
||
|
||
// Cleanup
|
||
free(quant_mid); free(quant_side); free(dwt_mid); free(dwt_side);
|
||
free(pcm32_left); free(pcm32_right); free(pcm8_left); free(pcm8_right);
|
||
if (decompressed) free(decompressed);
|
||
|
||
return 0;
|
||
}
|
||
|
||
//=============================================================================
|
||
// Main Decoder
|
||
//=============================================================================
|
||
|
||
static void print_usage(const char *prog_name) {
|
||
printf("Usage: %s -i <input> -o <output> [options]\n", prog_name);
|
||
printf("Options:\n");
|
||
printf(" -i <file> Input TAD file\n");
|
||
printf(" -o <file> Output PCMu8 file (raw 8-bit unsigned stereo @ 32kHz)\n");
|
||
printf(" -q <0-5> Quality level used during encoding (default: 3)\n");
|
||
printf(" -v Verbose output\n");
|
||
printf(" -h, --help Show this help\n");
|
||
printf("\nVersion: %s\n", DECODER_VENDOR_STRING);
|
||
printf("Output format: PCMu8 (unsigned 8-bit) stereo @ 32000 Hz\n");
|
||
printf("To convert to WAV: ffmpeg -f u8 -ar 32000 -ac 2 -i output.raw output.wav\n");
|
||
}
|
||
|
||
int main(int argc, char *argv[]) {
|
||
char *input_file = NULL;
|
||
char *output_file = NULL;
|
||
int quality = 3; // Must match encoder quality
|
||
int verbose = 0;
|
||
|
||
int opt;
|
||
while ((opt = getopt(argc, argv, "i:o:q:vh")) != -1) {
|
||
switch (opt) {
|
||
case 'i':
|
||
input_file = optarg;
|
||
break;
|
||
case 'o':
|
||
output_file = optarg;
|
||
break;
|
||
case 'q':
|
||
quality = atoi(optarg);
|
||
if (quality < TAD_QUALITY_MIN || quality > TAD_QUALITY_MAX) {
|
||
fprintf(stderr, "Error: Quality must be between %d and %d\n",
|
||
TAD_QUALITY_MIN, TAD_QUALITY_MAX);
|
||
return 1;
|
||
}
|
||
break;
|
||
case 'v':
|
||
verbose = 1;
|
||
break;
|
||
case 'h':
|
||
print_usage(argv[0]);
|
||
return 0;
|
||
default:
|
||
print_usage(argv[0]);
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
if (!input_file || !output_file) {
|
||
fprintf(stderr, "Error: Input and output files are required\n");
|
||
print_usage(argv[0]);
|
||
return 1;
|
||
}
|
||
|
||
if (verbose) {
|
||
printf("%s\n", DECODER_VENDOR_STRING);
|
||
printf("Input: %s\n", input_file);
|
||
printf("Output: %s\n", output_file);
|
||
printf("Quality: %d\n", quality);
|
||
}
|
||
|
||
// Open input file
|
||
FILE *input = fopen(input_file, "rb");
|
||
if (!input) {
|
||
fprintf(stderr, "Error: Could not open input file: %s\n", input_file);
|
||
return 1;
|
||
}
|
||
|
||
// Get file size
|
||
fseek(input, 0, SEEK_END);
|
||
size_t input_size = ftell(input);
|
||
fseek(input, 0, SEEK_SET);
|
||
|
||
// Read entire file into memory
|
||
uint8_t *input_data = malloc(input_size);
|
||
fread(input_data, 1, input_size, input);
|
||
fclose(input);
|
||
|
||
// Open output file
|
||
FILE *output = fopen(output_file, "wb");
|
||
if (!output) {
|
||
fprintf(stderr, "Error: Could not open output file: %s\n", output_file);
|
||
free(input_data);
|
||
return 1;
|
||
}
|
||
|
||
// Decode chunks
|
||
size_t offset = 0;
|
||
size_t chunk_count = 0;
|
||
size_t total_samples = 0;
|
||
// Allocate buffer for maximum chunk size (can handle variable sizes up to default)
|
||
uint8_t *chunk_output = malloc(TAD_DEFAULT_CHUNK_SIZE * TAD_CHANNELS);
|
||
|
||
while (offset < input_size) {
|
||
size_t bytes_consumed, samples_decoded;
|
||
int result = decode_chunk(input_data + offset, input_size - offset,
|
||
chunk_output, quality, &bytes_consumed, &samples_decoded);
|
||
|
||
if (result != 0) {
|
||
fprintf(stderr, "Error: Chunk decoding failed at offset %zu\n", offset);
|
||
free(input_data);
|
||
free(chunk_output);
|
||
fclose(output);
|
||
return 1;
|
||
}
|
||
|
||
// Write decoded chunk (only the actual samples)
|
||
fwrite(chunk_output, TAD_CHANNELS, samples_decoded, output);
|
||
|
||
offset += bytes_consumed;
|
||
total_samples += samples_decoded;
|
||
chunk_count++;
|
||
|
||
if (verbose && (chunk_count % 10 == 0)) {
|
||
printf("Decoded chunk %zu (offset %zu/%zu, %zu samples)\r", chunk_count, offset, input_size, samples_decoded);
|
||
fflush(stdout);
|
||
}
|
||
}
|
||
|
||
if (verbose) {
|
||
printf("\nDecoding complete!\n");
|
||
printf("Decoded %zu chunks\n", chunk_count);
|
||
printf("Total samples: %zu (%.2f seconds)\n",
|
||
total_samples,
|
||
total_samples / (double)TAD_SAMPLE_RATE);
|
||
}
|
||
|
||
// Cleanup
|
||
free(input_data);
|
||
free(chunk_output);
|
||
fclose(output);
|
||
|
||
printf("Output written to: %s\n", output_file);
|
||
printf("Format: PCMu8 stereo @ %d Hz\n", TAD_SAMPLE_RATE);
|
||
|
||
return 0;
|
||
}
|