1 files changed, 161 insertions, 0 deletions
diff --git a/tools/spectool.cpp b/tools/spectool.cpp
new file mode 100644
index 0000000..3b3d3aa
--- /dev/null
+++ b/tools/spectool.cpp
@@ -0,0 +1,161 @@
+#include <stdio.h>
+#include <string.h>
+#include "audio/dct.h"
+#include "audio/window.h"
+#include "audio/synth.h"
+#include "platform.h"
+#include "audio/audio.h"
+
+// Define MINIAUDIO_IMPLEMENTATION in one C/C++ file.
+#define MINIAUDIO_IMPLEMENTATION
+#include "miniaudio.h"
+
+#include <vector>
+
+// Simple .spec file format:
+// char[4] magic = "SPEC"
+// int32_t version = 1
+// int32_t dct_size
+// int32_t num_frames
+// float[num_frames * dct_size] data
+struct SpecHeader {
+    char magic[4];
+    int32_t version;
+    int32_t dct_size;
+    int32_t num_frames;
+};
+
+int analyze_audio(const char* in_path, const char* out_path) {
+    printf("Analyzing %s -> %s\n", in_path, out_path);
+
+    ma_decoder_config config = ma_decoder_config_init(ma_format_f32, 1, 32000);
+    ma_decoder decoder;
+    if (ma_decoder_init_file(in_path, &config, &decoder) != MA_SUCCESS) {
+        printf("Error: Failed to open or decode audio file: %s\n", in_path);
+        return 1;
+    }
+
+    std::vector<float> spec_data;
+    float pcm_chunk[DCT_SIZE];
+    float window[WINDOW_SIZE];
+    hamming_window_512(window);
+
+    ma_uint64 frames_read;
+    while (ma_decoder_read_pcm_frames(&decoder, pcm_chunk, DCT_SIZE, &frames_read) == MA_SUCCESS && frames_read > 0) {
+        if (frames_read < DCT_SIZE) {
+            // Zero-pad the last chunk if it's smaller
+            memset(pcm_chunk + frames_read, 0, (DCT_SIZE - frames_read) * sizeof(float));
+        }
+
+        // Apply window
+        for (int i = 0; i < DCT_SIZE; ++i) {
+            pcm_chunk[i] *= window[i];
+        }
+
+        // Apply FDCT
+        float dct_chunk[DCT_SIZE];
+        fdct_512(pcm_chunk, dct_chunk);
+
+        // Add to spectrogram data
+        spec_data.insert(spec_data.end(), dct_chunk, dct_chunk + DCT_SIZE);
+    }
+
+    ma_decoder_uninit(&decoder);
+
+    // Write to .spec file
+    FILE* f_out = fopen(out_path, "wb");
+    if (!f_out) {
+        printf("Error: Failed to open output file: %s\n", out_path);
+        return 1;
+    }
+
+    SpecHeader header;
+    memcpy(header.magic, "SPEC", 4);
+    header.version = 1;
+    header.dct_size = DCT_SIZE;
+    header.num_frames = spec_data.size() / DCT_SIZE;
+
+    fwrite(&header, sizeof(SpecHeader), 1, f_out);
+    fwrite(spec_data.data(), sizeof(float), spec_data.size(), f_out);
+    fclose(f_out);
+
+    printf("Analysis complete. Wrote %d spectral frames.\n", header.num_frames);
+    return 0;
+}
+
+int play_spec(const char* in_path) {
+    printf("Playing %s\n", in_path);
+
+    FILE* f_in = fopen(in_path, "rb");
+    if (!f_in) {
+        printf("Error: Failed to open input file: %s\n", in_path);
+        return 1;
+    }
+
+    SpecHeader header;
+    if (fread(&header, sizeof(SpecHeader), 1, f_in) != 1 || strncmp(header.magic, "SPEC", 4) != 0) {
+        printf("Error: Invalid spectrogram file format.\n");
+        fclose(f_in);
+        return 1;
+    }
+
+    std::vector<float> spec_data(header.num_frames * header.dct_size);
+    fread(spec_data.data(), sizeof(float), spec_data.size(), f_in);
+    fclose(f_in);
+
+    platform_init();
+    audio_init();
+
+    Spectrogram spec;
+    spec.spectral_data_a = spec_data.data();
+    spec.spectral_data_b = spec_data.data(); // Point both to the same buffer for playback
+    spec.num_frames = header.num_frames;
+
+    int spec_id = synth_register_spectrogram(&spec);
+    synth_trigger_voice(spec_id, 0.7f, 0.0f);
+
+    printf("Playing... Press Ctrl+C to exit.\n");
+    while (synth_get_active_voice_count() > 0 && !platform_should_close()) {
+        platform_poll();
+    }
+
+
+    audio_shutdown();
+    platform_shutdown();
+
+    return 0;
+}
+
+void print_usage() {
+    printf("Usage: spectool <command> <input> [output]\n");
+    printf("Commands:\n");
+    printf("  analyze <input.wav|.mp3> <output.spec>   Analyze an audio file and save as a spectrogram.\n");
+    printf("  play    <input.spec>                     Play a spectrogram file.\n");
+}
+
+int main(int argc, char** argv) {
+    if (argc < 3) {
+        print_usage();
+        return 1;
+    }
+
+    const char* command = argv[1];
+    const char* input_path = argv[2];
+
+    if (strcmp(command, "analyze") == 0) {
+        if (argc < 4) {
+            printf("Error: 'analyze' command requires an output file.\n");
+            print_usage();
+            return 1;
+        }
+        return analyze_audio(input_path, argv[3]);
+    } else if (strcmp(command, "play") == 0) {
+        return play_spec(input_path);
+    } else {
+        printf("Error: Unknown command '%s'\n", command);
+        print_usage();
+        return 1;
+    }
+
+    return 0;
+}