init

2026-07-14 00:26:01 +02:00
commit a2f8c110c4
30 changed files with 3525 additions and 0 deletions
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+//
+// Created by bruno on 13. 7. 2026.
+//
+
+#ifndef AUDIOCODER_DECODER_H
+#define AUDIOCODER_DECODER_H
+
+#define MAX_BITS 16
+#define PREAMBLE_SYMBOLS 128
+#define DECODER_SAMPLE_HISTORY 262144
+#include <SDL_audio.h>
+#include <SDL_render.h>
+#include <stdint.h>
+
+#include "goertzel.h"
+
+typedef enum {
+    RX_SEARCH,
+    RX_ALIGN,
+    RX_SYNC,
+    RX_LOCKED
+} RxState;
+
+typedef struct {
+
+    uint8_t bitCount;
+
+    uint16_t startFreq;
+    uint16_t endFreq;
+    uint16_t dataSpacing;
+
+    uint16_t clock0;
+    uint16_t clock1;
+
+
+    uint32_t symbolSamples;
+
+
+    uint32_t sampleCount;
+
+    float sampleHistory[DECODER_SAMPLE_HISTORY];
+    uint32_t sampleHistoryWrite;
+    uint32_t sampleHistoryCount;
+    uint64_t totalSamples;
+
+    Goertzel tones[MAX_BITS * 2 + 2];
+
+    uint8_t currentByte;
+    uint8_t bitIndex;
+
+    uint8_t buffer[1024*1024*8];
+
+    uint32_t bufferSize;
+
+    bool lastClock;
+
+
+    float energies[MAX_BITS * 2 + 2];
+    float maxEnergy;
+    float clockEnergy0;
+    float clockEnergy1;
+    float clockRatio;
+    uint8_t lastDecodedByte;
+    int bestSyncScore;
+    int bestSyncPhase;
+
+    RxState rxState;
+
+    bool expectedClock;
+    float lastClockEnergy;
+    uint32_t goodClocks;
+    uint32_t syncIndex;
+    uint32_t badClocks;
+
+    uint64_t phaseSearchStart;
+    uint32_t phaseWait;
+    int phaseOffset;
+    bool phaseSearchReady;
+
+    uint32_t searchOffset;
+    uint32_t syncOffset;
+    uint8_t clockHistory;
+    uint8_t clockCount;
+
+    bool locked;
+
+    SDL_Renderer *renderer;
+
+} Decoder;
+
+
+
+void decoder_init(
+        Decoder *dec
+);
+
+
+void decoder_process(
+        Decoder *dec,
+        float *samples,
+        uint32_t count
+);
+
+void decoder_rebuild_tones(
+        Decoder *dec
+);
+
+extern Decoder decoder;
+extern SDL_AudioDeviceID inputDev;
+extern const uint8_t syncBytes[4];
+
+// Internal audio bus for loopback
+#define INTERNAL_BUFFER_SIZE 262144
+extern float internalBusSamples[INTERNAL_BUFFER_SIZE];
+extern volatile uint32_t internalBusWrite;
+extern volatile uint32_t internalBusRead;
+
+void initAudioDecoder(SDL_Renderer *renderer);
+
+#endif //AUDIOCODER_DECODER_H