tav: librarying

video_encoder/include/encoder_tad.h

@@ -0,0 +1,61 @@
+#ifndef TAD32_ENCODER_H
+#define TAD32_ENCODER_H
+
+#include <stdint.h>
+#include <stddef.h>
+
+// TAD32 (Terrarum Advanced Audio - PCM32f version) Encoder
+// DWT-based perceptual audio codec for TSVM
+// Alternative version: PCM32f throughout encoding, PCM8 conversion only at decoder
+
+// Constants
+#define TAD32_COEFF_SCALARS {64.0f, 45.255f, 32.0f, 22.627f, 16.0f, 11.314f, 8.0f, 5.657f, 4.0f, 2.828f} // value only valid for CDF 9/7 with decomposition level 9. Index 0 = LL band
+#define TAD32_MIN_CHUNK_SIZE 1024       // Minimum: 1024 samples
+#define TAD32_SAMPLE_RATE 32000
+#define TAD32_CHANNELS 2  // Stereo
+#define TAD32_QUALITY_MIN 0
+#define TAD32_QUALITY_MAX 6
+#define TAD32_QUALITY_DEFAULT 3
+#define TAD32_ZSTD_LEVEL 15
+
+static inline int tad32_quality_to_max_index(int quality) {
+    static const int quality_map[6] = {21, 31, 44, 63, 89, 127};
+    if (quality < 0) quality = 0;
+    if (quality > 5) quality = 5;
+    return quality_map[quality];
+}
+
+/**
+ * Encode audio chunk with TAD32 codec (PCM32f version)
+ *
+ * @param pcm32_stereo    Input PCM32fLE stereo samples (interleaved L,R)
+ * @param num_samples     Number of samples per channel (min 1024)
+ * @param max_index       Maximum quantisation index (7=3bit, 15=4bit, 31=5bit, 63=6bit, 127=7bit)
+ * @param quantiser_scale Quantiser scaling factor (1.0=baseline, 2.0=2x coarser quantisation)
+ *                        Higher values = more aggressive quantisation = smaller files
+ * @param output          Output buffer (must be large enough)
+ * @return                Number of bytes written to output, or 0 on error
+ *
+ * Output format:
+ *   uint16 sample_count (samples per channel)
+ *   uint8  max_index (maximum quantisation index)
+ *   uint32 payload_size (bytes in payload)
+ *   *      payload (encoded M/S data, Zstd-compressed with 2-bit twobitmap)
+ */
+size_t tad32_encode_chunk(const float *pcm32_stereo, size_t num_samples,
+                          int max_index,
+                          float quantiser_scale, uint8_t *output);
+
+/**
+ * Print accumulated coefficient statistics
+ * Only effective if TAD_COEFF_STATS environment variable is set
+ */
+void tad32_print_statistics(void);
+
+/**
+ * Free accumulated statistics memory
+ * Should be called after tad32_print_statistics()
+ */
+void tad32_free_statistics(void);
+
+#endif // TAD32_ENCODER_H