mirror of
https://github.com/curioustorvald/tsvm.git
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802 lines
27 KiB
C
802 lines
27 KiB
C
// Created by CuriousTorvald and Claude on 2025-10-23.
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// TAD (Terrarum Advanced Audio) Decoder - Reconstructs audio from TAD format
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#include <stdio.h>
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#include <stdlib.h>
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#include <stdint.h>
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#include <string.h>
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#include <math.h>
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#include <zstd.h>
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#include <getopt.h>
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#define DECODER_VENDOR_STRING "Decoder-TAD 20251026"
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// TAD format constants (must match encoder)
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#undef TAD32_COEFF_SCALARS
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// Coefficient scalars for each subband (CDF 9/7 with 9 decomposition levels)
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// Index 0 = LL band, Index 1-9 = H bands (L9 to L1)
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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};
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// Base quantiser weight table (10 subbands: LL + 9 H bands)
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// Linearly spaced from 1.0 (LL) to 2.0 (H9)
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// These weights are multiplied by quantiser_scale during dequantization
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static const float BASE_QUANTISER_WEIGHTS[] = {
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1.0f, // LL (L9) - finest preservation
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1.0f, // H (L9)
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1.0f, // H (L8)
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1.0f, // H (L7)
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1.0f, // H (L6)
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1.1f, // H (L5)
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1.2f, // H (L4)
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1.3f, // H (L3)
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1.4f, // H (L2)
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1.5f // H (L1) - coarsest quantization
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};
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#define TAD_DEFAULT_CHUNK_SIZE 32768
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#define TAD_MIN_CHUNK_SIZE 1024
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#define TAD_SAMPLE_RATE 32000
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#define TAD_CHANNELS 2
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// Significance map methods
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#define TAD_SIGMAP_1BIT 0
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#define TAD_SIGMAP_2BIT 1
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#define TAD_SIGMAP_RLE 2
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// Quality levels
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#define TAD_QUALITY_MIN 0
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#define TAD_QUALITY_MAX 5
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static inline float FCLAMP(float x, float min, float max) {
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return x < min ? min : (x > max ? max : x);
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}
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//=============================================================================
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// Deterministic PRNG for Coefficient-Domain Dithering
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//=============================================================================
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// Simple LCG for reproducible dithering
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static inline uint32_t lcg_next(uint32_t *seed) {
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*seed = (*seed * 1664525u) + 1013904223u;
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return *seed;
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}
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// Uniform random in [0, 1)
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static inline float uniform_01(uint32_t *seed) {
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return (lcg_next(seed) & 0xFFFFFF) / 16777216.0f;
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}
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// TPDF (Triangular Probability Distribution Function) dither in range (-1, 1)
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static inline float tpdf_dither(uint32_t *seed) {
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float u1 = uniform_01(seed) - 0.5f; // [-0.5, 0.5)
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float u2 = uniform_01(seed) - 0.5f; // [-0.5, 0.5)
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return u1 - u2; // Triangular distribution in (-1, 1)
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}
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// Calculate per-subband dither scaling factor
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// alpha = 0.0 → flat per-band noise
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// alpha = 0.5 → pinkish noise (default)
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// alpha = 1.0 → more noise in low bands
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static inline float subband_dither_scale(int level, float alpha) {
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return (powf(alpha, level / 10.0f) - 1.0f) / alpha;
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}
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//=============================================================================
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// WAV Header Writing
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//=============================================================================
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static void write_wav_header(FILE *output, uint32_t data_size, uint16_t channels, uint32_t sample_rate, uint16_t bits_per_sample) {
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uint32_t byte_rate = sample_rate * channels * bits_per_sample / 8;
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uint16_t block_align = channels * bits_per_sample / 8;
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uint32_t chunk_size = 36 + data_size;
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// RIFF header
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fwrite("RIFF", 1, 4, output);
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fwrite(&chunk_size, 4, 1, output);
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fwrite("WAVE", 1, 4, output);
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// fmt chunk
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fwrite("fmt ", 1, 4, output);
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uint32_t fmt_size = 16;
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fwrite(&fmt_size, 4, 1, output);
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uint16_t audio_format = 1; // PCM
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fwrite(&audio_format, 2, 1, output);
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fwrite(&channels, 2, 1, output);
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fwrite(&sample_rate, 4, 1, output);
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fwrite(&byte_rate, 4, 1, output);
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fwrite(&block_align, 2, 1, output);
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fwrite(&bits_per_sample, 2, 1, output);
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// data chunk header
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fwrite("data", 1, 4, output);
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fwrite(&data_size, 4, 1, output);
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}
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// Calculate DWT levels from chunk size (must be power of 2, >= 1024)
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static int calculate_dwt_levels(int chunk_size) {
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/*if (chunk_size < TAD_MIN_CHUNK_SIZE) {
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fprintf(stderr, "Error: Chunk size %d is below minimum %d\n", chunk_size, TAD_MIN_CHUNK_SIZE);
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return -1;
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}
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// Calculate levels: log2(chunk_size) - 1
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int levels = 0;
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int size = chunk_size;
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while (size > 1) {
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size >>= 1;
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levels++;
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}
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return levels - 2;*/
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return 9;
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}
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//=============================================================================
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// Haar DWT Implementation (inverse only needed for decoder)
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//=============================================================================
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static void dwt_haar_inverse_1d(float *data, int length) {
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if (length < 2) return;
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float *temp = malloc(length * sizeof(float));
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int half = (length + 1) / 2;
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for (int i = 0; i < half; i++) {
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if (2 * i + 1 < length) {
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temp[2 * i] = data[i] + data[half + i];
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temp[2 * i + 1] = data[i] - data[half + i];
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} else {
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temp[2 * i] = data[i];
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}
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}
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memcpy(data, temp, length * sizeof(float));
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free(temp);
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}
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// 9/7 inverse DWT (from TSVM Kotlin code)
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static void dwt_97_inverse_1d(float *data, int length) {
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if (length < 2) return;
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float *temp = malloc(length * sizeof(float));
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int half = (length + 1) / 2;
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// Split into low and high frequency components (matching TSVM layout)
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for (int i = 0; i < half; i++) {
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temp[i] = data[i]; // Low-pass coefficients (first half)
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}
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for (int i = 0; i < length / 2; i++) {
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if (half + i < length) {
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temp[half + i] = data[half + i]; // High-pass coefficients (second half)
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}
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}
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// 9/7 inverse lifting coefficients from TSVM
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const float alpha = -1.586134342f;
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const float beta = -0.052980118f;
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const float gamma = 0.882911076f;
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const float delta = 0.443506852f;
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const float K = 1.230174105f;
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// Step 1: Undo scaling
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for (int i = 0; i < half; i++) {
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temp[i] /= K; // Low-pass coefficients
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}
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for (int i = 0; i < length / 2; i++) {
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if (half + i < length) {
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temp[half + i] *= K; // High-pass coefficients
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}
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}
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// Step 2: Undo δ update
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for (int i = 0; i < half; i++) {
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float d_curr = (half + i < length) ? temp[half + i] : 0.0f;
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float d_prev = (i > 0 && half + i - 1 < length) ? temp[half + i - 1] : d_curr;
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temp[i] -= delta * (d_curr + d_prev);
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}
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// Step 3: Undo γ predict
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for (int i = 0; i < length / 2; i++) {
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if (half + i < length) {
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float s_curr = temp[i];
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float s_next = (i + 1 < half) ? temp[i + 1] : s_curr;
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temp[half + i] -= gamma * (s_curr + s_next);
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}
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}
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// Step 4: Undo β update
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for (int i = 0; i < half; i++) {
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float d_curr = (half + i < length) ? temp[half + i] : 0.0f;
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float d_prev = (i > 0 && half + i - 1 < length) ? temp[half + i - 1] : d_curr;
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temp[i] -= beta * (d_curr + d_prev);
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}
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// Step 5: Undo α predict
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for (int i = 0; i < length / 2; i++) {
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if (half + i < length) {
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float s_curr = temp[i];
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float s_next = (i + 1 < half) ? temp[i + 1] : s_curr;
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temp[half + i] -= alpha * (s_curr + s_next);
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}
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}
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// Reconstruction - interleave low and high pass
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for (int i = 0; i < length; i++) {
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if (i % 2 == 0) {
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// Even positions: low-pass coefficients
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data[i] = temp[i / 2];
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} else {
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// Odd positions: high-pass coefficients
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int idx = i / 2;
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if (half + idx < length) {
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data[i] = temp[half + idx];
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} else {
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data[i] = 0.0f;
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}
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}
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}
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free(temp);
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}
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// Inverse 1D transform of Four-point interpolating Deslauriers-Dubuc (DD-4)
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static void dwt_dd4_inverse_1d(float *data, int length) {
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if (length < 2) return;
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float *temp = malloc(length * sizeof(float));
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int half = (length + 1) / 2;
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// Split into low (even) and high (odd) parts
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for (int i = 0; i < half; i++) {
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temp[i] = data[i]; // Even (low-pass)
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}
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for (int i = 0; i < length / 2; i++) {
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temp[half + i] = data[half + i]; // Odd (high-pass)
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}
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// Undo update step: s[i] -= 0.25 * (d[i-1] + d[i])
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for (int i = 0; i < half; i++) {
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float d_curr = (i < length / 2) ? temp[half + i] : 0.0f;
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float d_prev = (i > 0 && i - 1 < length / 2) ? temp[half + i - 1] : 0.0f;
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temp[i] -= 0.25f * (d_prev + d_curr);
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}
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// Undo prediction step: d[i] += P(s[i-1], s[i], s[i+1], s[i+2])
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for (int i = 0; i < length / 2; i++) {
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float s_m1, s_0, s_1, s_2;
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if (i > 0) s_m1 = temp[i - 1];
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else s_m1 = temp[0]; // mirror boundary
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s_0 = temp[i];
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if (i + 1 < half) s_1 = temp[i + 1];
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else s_1 = temp[half - 1];
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if (i + 2 < half) s_2 = temp[i + 2];
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else if (half > 1) s_2 = temp[half - 2];
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else s_2 = temp[half - 1];
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float prediction = (-1.0f/16.0f)*s_m1 + (9.0f/16.0f)*s_0 +
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(9.0f/16.0f)*s_1 + (-1.0f/16.0f)*s_2;
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temp[half + i] += prediction;
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}
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// Merge evens and odds back into the original order
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for (int i = 0; i < half; i++) {
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data[2 * i] = temp[i];
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if (2 * i + 1 < length)
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data[2 * i + 1] = temp[half + i];
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}
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free(temp);
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}
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static void dwt_haar_inverse_multilevel(float *data, int length, int levels) {
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// Calculate the length at the deepest level (size of low-pass after all forward DWTs)
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int current_length = length;
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for (int level = 0; level < levels; level++) {
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current_length = (current_length + 1) / 2;
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}
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// For 8 levels on 32768: 32768→16384→8192→4096→2048→1024→512→256→128
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// Inverse transform: double size FIRST, then apply inverse DWT
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// Level 8 inverse: 128 low + 128 high → 256 reconstructed
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// Level 7 inverse: 256 reconstructed + 256 high → 512 reconstructed
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// ... Level 1 inverse: 16384 reconstructed + 16384 high → 32768 reconstructed
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for (int level = levels - 1; level >= 0; level--) {
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current_length *= 2; // MULTIPLY FIRST: 128→256, 256→512, ..., 16384→32768
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if (current_length > length) current_length = length;
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// dwt_haar_inverse_1d(data, current_length); // THEN apply inverse
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// dwt_dd4_inverse_1d(data, current_length); // THEN apply inverse
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dwt_97_inverse_1d(data, current_length); // THEN apply inverse
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}
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}
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//=============================================================================
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// M/S Stereo Correlation (inverse of decorrelation)
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//=============================================================================
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// Uniform random in [0, 1)
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static inline float frand01(void) {
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return (float)rand() / ((float)RAND_MAX + 1.0f);
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}
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// TPDF noise in [-1, +1)
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static inline float tpdf1(void) {
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return (frand01() - frand01());
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}
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static void ms_correlate(const float *mid, const float *side, float *left, float *right, size_t count) {
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for (size_t i = 0; i < count; i++) {
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// Decode M/S → L/R
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float m = mid[i];
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float s = side[i];
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left[i] = FCLAMP((m + s), -1.0f, 1.0f);
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right[i] = FCLAMP((m - s), -1.0f, 1.0f);
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}
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}
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static float signum(float x) {
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if (x > 0.0f) return 1.0f;
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if (x < 0.0f) return -1.0f;
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return 0.0f;
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}
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static void expand_gamma(float *left, float *right, size_t count) {
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for (size_t i = 0; i < count; i++) {
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// decode(y) = sign(y) * |y|^(1/γ) where γ=0.5
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float x = left[i]; float a = fabsf(x);
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left[i] = signum(x) * powf(a, 1.4142f);
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float y = right[i]; float b = fabsf(y);
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right[i] = signum(y) * powf(b, 1.4142f);
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}
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}
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static void expand_mu_law(float *left, float *right, size_t count) {
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static float MU = 255.0f;
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for (size_t i = 0; i < count; i++) {
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// decode(y) = sign(y) * |y|^(1/γ) where γ=0.5
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float x = left[i];
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left[i] = signum(x) * (powf(1.0f + MU, fabsf(x)) - 1.0f) / MU;
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float y = right[i];
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right[i] = signum(y) * (powf(1.0f + MU, fabsf(y)) - 1.0f) / MU;
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}
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}
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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]) {
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const float b1 = 1.5f; // 1st feedback coefficient
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const float b2 = -0.75f; // 2nd feedback coefficient
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const float scale = 127.5f;
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const float bias = 128.0f;
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// Reduced dither amplitude to coordinate with coefficient-domain dithering
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// The decoder now adds TPDF dither in coefficient domain, so we reduce
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// sample-domain dither by ~60% to avoid doubling the noise floor
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const float dither_scale = 0.2f; // Reduced from 0.5 (was ±0.5 LSB, now ±0.2 LSB)
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for (size_t i = 0; i < count; i++) {
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// --- LEFT channel ---
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float feedbackL = b1 * dither_error[0][0] + b2 * dither_error[0][1];
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float ditherL = dither_scale * tpdf1(); // Reduced TPDF dither
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float shapedL = fleft[i] + feedbackL + ditherL / scale;
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shapedL = FCLAMP(shapedL, -1.0f, 1.0f);
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int qL = (int)lrintf(shapedL * scale);
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if (qL < -128) qL = -128;
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else if (qL > 127) qL = 127;
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left[i] = (uint8_t)(qL + bias);
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float qerrL = shapedL - (float)qL / scale;
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dither_error[0][1] = dither_error[0][0]; // shift history
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dither_error[0][0] = qerrL;
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// --- RIGHT channel ---
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float feedbackR = b1 * dither_error[1][0] + b2 * dither_error[1][1];
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float ditherR = dither_scale * tpdf1(); // Reduced TPDF dither
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float shapedR = fright[i] + feedbackR + ditherR / scale;
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shapedR = FCLAMP(shapedR, -1.0f, 1.0f);
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int qR = (int)lrintf(shapedR * scale);
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if (qR < -128) qR = -128;
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else if (qR > 127) qR = 127;
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right[i] = (uint8_t)(qR + bias);
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float qerrR = shapedR - (float)qR / scale;
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dither_error[1][1] = dither_error[1][0];
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dither_error[1][0] = qerrR;
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}
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}
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//=============================================================================
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// Dequantization (inverse of quantization)
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//=============================================================================
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#define LAMBDA_FIXED 6.0f
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// Lambda-based decompanding decoder (inverse of Laplacian CDF-based encoder)
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// Converts quantized index back to normalized float in [-1, 1]
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static float lambda_decompanding(int8_t quant_val, int max_index) {
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// Handle zero
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if (quant_val == 0) {
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return 0.0f;
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}
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int sign = (quant_val < 0) ? -1 : 1;
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int abs_index = abs(quant_val);
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// Clamp to valid range
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if (abs_index > max_index) abs_index = max_index;
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// Map index back to normalized CDF [0, 1]
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float normalized_cdf = (float)abs_index / max_index;
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// Map from [0, 1] back to [0.5, 1.0] (CDF range for positive half)
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float cdf = 0.5f + normalized_cdf * 0.5f;
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// Inverse Laplacian CDF for x >= 0: x = -(1/λ) * ln(2*(1-F))
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// For F in [0.5, 1.0]: x = -(1/λ) * ln(2*(1-F))
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float abs_val = -(1.0f / LAMBDA_FIXED) * logf(2.0f * (1.0f - cdf));
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// Clamp to [0, 1]
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if (abs_val > 1.0f) abs_val = 1.0f;
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if (abs_val < 0.0f) abs_val = 0.0f;
|
||
|
||
return sign * abs_val;
|
||
}
|
||
|
||
static void dequantize_dwt_coefficients(const int8_t *quantized, float *coeffs, size_t count, int chunk_size, int dwt_levels, int max_index, float quantiser_scale, uint32_t *dither_seed) {
|
||
|
||
// 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));
|
||
}
|
||
|
||
// Coefficient-domain dithering parameters
|
||
const float dither_k = 0.125f; // Amplitude factor (0.5 × Q_level)
|
||
const float dither_alpha = 78.0f; // Subband scaling exponent (0.5 = pinkish)
|
||
|
||
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;
|
||
}
|
||
}
|
||
|
||
// Decode using lambda companding
|
||
float normalized_val = lambda_decompanding(quantized[i], max_index);
|
||
|
||
// Denormalize using the subband scalar and apply base weight + quantiser scaling
|
||
float weight = BASE_QUANTISER_WEIGHTS[sideband] * quantiser_scale;
|
||
float dequantized = normalized_val * TAD32_COEFF_SCALARS[sideband] * weight;
|
||
|
||
// Apply coefficient-domain dithering AFTER dequantization
|
||
// Calculate quantization step size Q in coefficient domain
|
||
float scalar = TAD32_COEFF_SCALARS[sideband] * weight;
|
||
float Q = scalar / max_index;
|
||
|
||
// Per-subband dither scaling: lower levels get more dither energy
|
||
float s_level = subband_dither_scale(sideband, dither_alpha);
|
||
|
||
// TPDF dithering in coefficient domain
|
||
float tpdf = tpdf_dither(dither_seed);
|
||
float dither_amplitude = dither_k * Q * s_level;
|
||
|
||
// Add dither to dequantized coefficient
|
||
coeffs[i] = dequantized + (tpdf * dither_amplitude);
|
||
}
|
||
|
||
free(sideband_starts);
|
||
}
|
||
|
||
//=============================================================================
|
||
// Chunk Decoding
|
||
//=============================================================================
|
||
|
||
static int decode_chunk(const uint8_t *input, size_t input_size, uint8_t *pcmu8_stereo,
|
||
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);
|
||
|
||
uint8_t max_index = *read_ptr;
|
||
read_ptr += sizeof(uint8_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(int8_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;
|
||
}
|
||
|
||
read_ptr += payload_size;
|
||
*bytes_consumed = read_ptr - input;
|
||
*samples_decoded = sample_count;
|
||
|
||
// Allocate working buffers
|
||
int8_t *quant_mid = malloc(sample_count * sizeof(int8_t));
|
||
int8_t *quant_side = malloc(sample_count * sizeof(int8_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));
|
||
|
||
// Separate Mid/Side
|
||
memcpy(quant_mid, decompressed, sample_count);
|
||
memcpy(quant_side, decompressed + sample_count, sample_count);
|
||
|
||
// Initialize deterministic dither seeds based on GLOBAL sample position
|
||
// This ensures reproducibility across multiple decoding runs
|
||
static size_t global_sample_position = 0;
|
||
uint32_t dither_seed_mid = 0x12345678u ^ (uint32_t)(global_sample_position / sample_count * 2);
|
||
uint32_t dither_seed_side = 0x87654321u ^ (uint32_t)(global_sample_position / sample_count * 2 + 1);
|
||
global_sample_position += sample_count;
|
||
|
||
// Dequantize with quantiser scaling and coefficient-domain dithering
|
||
// Use quantiser_scale = 1.0f for baseline (must match encoder)
|
||
float quantiser_scale = 1.0f;
|
||
dequantize_dwt_coefficients(quant_mid, dwt_mid, sample_count, sample_count, dwt_levels, max_index, quantiser_scale, &dither_seed_mid);
|
||
dequantize_dwt_coefficients(quant_side, dwt_side, sample_count, sample_count, dwt_levels, max_index, quantiser_scale, &dither_seed_side);
|
||
|
||
// 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> [options]\n", prog_name);
|
||
printf("Options:\n");
|
||
printf(" -i <file> Input TAD file\n");
|
||
printf(" -o <file> Output file (optional, auto-generated from input)\n");
|
||
printf(" Default: input_qNN.wav (or .pcm with --raw-pcm)\n");
|
||
printf(" --raw-pcm Output raw PCMu8 instead of WAV file\n");
|
||
printf(" -v Verbose output\n");
|
||
printf(" -h, --help Show this help\n");
|
||
printf("\nVersion: %s\n", DECODER_VENDOR_STRING);
|
||
printf("Default output: WAV file (8-bit unsigned PCM, stereo @ 32000 Hz)\n");
|
||
printf("With --raw-pcm: PCMu8 raw file (8-bit unsigned stereo @ 32000 Hz)\n");
|
||
}
|
||
|
||
int main(int argc, char *argv[]) {
|
||
char *input_file = NULL;
|
||
char *output_file = NULL;
|
||
int verbose = 0;
|
||
int raw_pcm = 0;
|
||
|
||
static struct option long_options[] = {
|
||
{"raw-pcm", no_argument, 0, 'r'},
|
||
{"help", no_argument, 0, 'h'},
|
||
{0, 0, 0, 0}
|
||
};
|
||
|
||
int opt;
|
||
int option_index = 0;
|
||
while ((opt = getopt_long(argc, argv, "i:o:vh", long_options, &option_index)) != -1) {
|
||
switch (opt) {
|
||
case 'i':
|
||
input_file = optarg;
|
||
break;
|
||
case 'o':
|
||
output_file = optarg;
|
||
break;
|
||
case 'r':
|
||
raw_pcm = 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) {
|
||
fprintf(stderr, "Error: Input file is required\n");
|
||
print_usage(argv[0]);
|
||
return 1;
|
||
}
|
||
|
||
// Generate output filename if not provided
|
||
if (!output_file) {
|
||
size_t input_len = strlen(input_file);
|
||
output_file = malloc(input_len + 32); // Extra space for extension
|
||
|
||
// Find the last directory separator
|
||
const char *basename_start = strrchr(input_file, '/');
|
||
if (!basename_start) basename_start = strrchr(input_file, '\\');
|
||
basename_start = basename_start ? basename_start + 1 : input_file;
|
||
|
||
// Copy directory part
|
||
size_t dir_len = basename_start - input_file;
|
||
strncpy(output_file, input_file, dir_len);
|
||
|
||
// Find the .tad extension
|
||
const char *ext = strrchr(basename_start, '.');
|
||
if (ext && strcmp(ext, ".tad") == 0) {
|
||
// Copy basename without .tad
|
||
size_t name_len = ext - basename_start;
|
||
strncpy(output_file + dir_len, basename_start, name_len);
|
||
output_file[dir_len + name_len] = '\0';
|
||
|
||
// Replace last dot with underscore (for .qNN pattern)
|
||
char *last_dot = strrchr(output_file, '.');
|
||
if (last_dot && last_dot > output_file + dir_len) {
|
||
*last_dot = '_';
|
||
}
|
||
} else {
|
||
// No .tad extension, copy entire basename
|
||
strcpy(output_file + dir_len, basename_start);
|
||
}
|
||
|
||
// Append appropriate extension
|
||
strcat(output_file, raw_pcm ? ".pcm" : ".wav");
|
||
|
||
if (verbose) {
|
||
printf("Auto-generated output path: %s\n", output_file);
|
||
}
|
||
}
|
||
|
||
if (verbose) {
|
||
printf("%s\n", DECODER_VENDOR_STRING);
|
||
printf("Input: %s\n", input_file);
|
||
printf("Output: %s\n", output_file);
|
||
}
|
||
|
||
// 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;
|
||
}
|
||
|
||
// Write placeholder WAV header if not in raw PCM mode
|
||
if (!raw_pcm) {
|
||
write_wav_header(output, 0, TAD_CHANNELS, TAD_SAMPLE_RATE, 8);
|
||
}
|
||
|
||
// 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, &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);
|
||
}
|
||
|
||
// Update WAV header with correct size if not in raw PCM mode
|
||
if (!raw_pcm) {
|
||
uint32_t data_size = total_samples * TAD_CHANNELS;
|
||
fseek(output, 0, SEEK_SET);
|
||
write_wav_header(output, data_size, TAD_CHANNELS, TAD_SAMPLE_RATE, 8);
|
||
}
|
||
|
||
// Cleanup
|
||
free(input_data);
|
||
free(chunk_output);
|
||
fclose(output);
|
||
|
||
printf("Output written to: %s\n", output_file);
|
||
if (raw_pcm) {
|
||
printf("Format: PCMu8 stereo @ %d Hz (raw PCM)\n", TAD_SAMPLE_RATE);
|
||
} else {
|
||
printf("Format: WAV file (8-bit unsigned PCM, stereo @ %d Hz)\n", TAD_SAMPLE_RATE);
|
||
}
|
||
|
||
return 0;
|
||
}
|