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// Standalone tool to play .spec or .wav files for debugging
// Usage: ./specplay <file.spec|file.wav>
#include "audio/dct.h"
#include "audio/window.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MINIAUDIO_IMPLEMENTATION
#include "miniaudio.h"
struct PlaybackState {
float* pcm_data;
size_t num_samples;
size_t playback_pos;
};
void audio_callback(ma_device* device, void* output, const void* input,
ma_uint32 frame_count) {
PlaybackState* state = (PlaybackState*)device->pUserData;
float* out = (float*)output;
for (ma_uint32 i = 0; i < frame_count; i++) {
if (state->playback_pos < state->num_samples) {
float sample = state->pcm_data[state->playback_pos++];
// Clamp to [-1, 1] and warn if clipping
if (sample > 1.0f || sample < -1.0f) {
fprintf(stderr, "[CLIP at sample %zu: %.3f]\n", state->playback_pos - 1,
sample);
sample = (sample > 1.0f) ? 1.0f : -1.0f;
}
out[i * 2] = sample; // Left
out[i * 2 + 1] = sample; // Right (mono)
} else {
out[i * 2] = 0.0f;
out[i * 2 + 1] = 0.0f;
}
}
}
float* load_spec(const char* path, size_t* out_num_samples) {
FILE* f = fopen(path, "rb");
if (!f) {
fprintf(stderr, "Failed to open %s\n", path);
return nullptr;
}
// Read SpecHeader
struct SpecHeader {
char magic[4];
int32_t version;
int32_t dct_size;
int32_t num_frames;
};
SpecHeader header;
if (fread(&header, sizeof(SpecHeader), 1, f) != 1) {
fprintf(stderr, "Failed to read SpecHeader\n");
fclose(f);
return nullptr;
}
// Validate header
if (memcmp(header.magic, "SPEC", 4) != 0) {
fprintf(stderr, "Invalid magic bytes (expected 'SPEC')\n");
fclose(f);
return nullptr;
}
printf("Loading .spec: version=%d, dct_size=%d, frames=%d\n", header.version,
header.dct_size, header.num_frames);
uint32_t num_frames = header.num_frames;
// Read spectral data
size_t spec_size = num_frames * DCT_SIZE;
float* spec_data = (float*)malloc(spec_size * sizeof(float));
if (fread(spec_data, sizeof(float), spec_size, f) != spec_size) {
fprintf(stderr, "Failed to read spectral data\n");
free(spec_data);
fclose(f);
return nullptr;
}
fclose(f);
// Convert to PCM via IDCT
*out_num_samples = spec_size;
float* pcm_data = (float*)malloc(*out_num_samples * sizeof(float));
for (uint32_t frame = 0; frame < num_frames; frame++) {
const float* spectral_frame = spec_data + (frame * DCT_SIZE);
float* time_frame = pcm_data + (frame * DCT_SIZE);
idct_512(spectral_frame, time_frame);
}
free(spec_data);
// Analyze PCM statistics
float peak = 0.0f, rms_sum = 0.0f;
for (size_t i = 0; i < *out_num_samples; i++) {
float abs_val = fabsf(pcm_data[i]);
if (abs_val > peak)
peak = abs_val;
rms_sum += pcm_data[i] * pcm_data[i];
}
float rms = sqrtf(rms_sum / *out_num_samples);
printf("PCM stats: Peak=%.3f, RMS=%.3f\n", peak, rms);
if (peak > 1.0f) {
printf("[WARNING] Peak exceeds 1.0! Will clip during playback.\n");
}
return pcm_data;
}
float* load_wav(const char* path, size_t* out_num_samples) {
ma_decoder decoder;
ma_decoder_config config = ma_decoder_config_init(ma_format_f32, 1, 32000);
if (ma_decoder_init_file(path, &config, &decoder) != MA_SUCCESS) {
fprintf(stderr, "Failed to open WAV file: %s\n", path);
return nullptr;
}
ma_uint64 frame_count;
ma_decoder_get_length_in_pcm_frames(&decoder, &frame_count);
*out_num_samples = (size_t)frame_count;
float* pcm_data = (float*)malloc(*out_num_samples * sizeof(float));
ma_decoder_read_pcm_frames(&decoder, pcm_data, frame_count, nullptr);
ma_decoder_uninit(&decoder);
printf("Loaded .wav: %zu samples\n", *out_num_samples);
// Analyze PCM statistics
float peak = 0.0f, rms_sum = 0.0f;
for (size_t i = 0; i < *out_num_samples; i++) {
float abs_val = fabsf(pcm_data[i]);
if (abs_val > peak)
peak = abs_val;
rms_sum += pcm_data[i] * pcm_data[i];
}
float rms = sqrtf(rms_sum / *out_num_samples);
printf("PCM stats: Peak=%.3f, RMS=%.3f\n", peak, rms);
return pcm_data;
}
int main(int argc, char** argv) {
if (argc != 2) {
fprintf(stderr, "Usage: %s <file.spec|file.wav>\n", argv[0]);
return 1;
}
const char* path = argv[1];
const char* ext = strrchr(path, '.');
PlaybackState state = {};
if (ext && strcmp(ext, ".spec") == 0) {
state.pcm_data = load_spec(path, &state.num_samples);
} else if (ext && (strcmp(ext, ".wav") == 0 || strcmp(ext, ".aif") == 0)) {
state.pcm_data = load_wav(path, &state.num_samples);
} else {
fprintf(stderr, "Unknown file type: %s\n", path);
return 1;
}
if (!state.pcm_data) {
fprintf(stderr, "Failed to load audio\n");
return 1;
}
printf("Playing %.2f seconds... Press Ctrl+C to stop.\n",
(float)state.num_samples / 32000.0f);
// Initialize miniaudio
ma_device_config device_config =
ma_device_config_init(ma_device_type_playback);
device_config.playback.format = ma_format_f32;
device_config.playback.channels = 2;
device_config.sampleRate = 32000;
device_config.dataCallback = audio_callback;
device_config.pUserData = &state;
ma_device device;
if (ma_device_init(NULL, &device_config, &device) != MA_SUCCESS) {
fprintf(stderr, "Failed to initialize audio device\n");
free(state.pcm_data);
return 1;
}
if (ma_device_start(&device) != MA_SUCCESS) {
fprintf(stderr, "Failed to start audio device\n");
ma_device_uninit(&device);
free(state.pcm_data);
return 1;
}
// Wait for playback to finish
while (state.playback_pos < state.num_samples) {
ma_sleep(100);
}
ma_device_uninit(&device);
free(state.pcm_data);
printf("Playback complete.\n");
return 0;
}
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