resurrecting delta encoding

This commit is contained in:
minjaesong
2025-09-22 02:47:46 +09:00
parent 28624309d7
commit be43384968
2 changed files with 143 additions and 335 deletions

View File

@@ -23,9 +23,9 @@
// TSVM Advanced Video (TAV) format constants
#define TAV_MAGIC "\x1F\x54\x53\x56\x4D\x54\x41\x56" // "\x1FTSVM TAV"
// TAV version - dynamic based on colour space and perceptual tuning
// Version 5: YCoCg-R monoblock with perceptual quantization (default)
// Version 6: ICtCp monoblock with perceptual quantization (--ictcp flag)
// Legacy versions (uniform quantization):
// Version 5: YCoCg-R monoblock with perceptual quantisation (default)
// Version 6: ICtCp monoblock with perceptual quantisation (--ictcp flag)
// Legacy versions (uniform quantisation):
// Version 3: YCoCg-R monoblock uniform (--no-perceptual-tuning)
// Version 4: ICtCp monoblock uniform (--ictcp --no-perceptual-tuning)
// Version 1: YCoCg-R 4-tile (legacy, code preserved but not accessible)
@@ -45,7 +45,7 @@
// DWT settings
#define TILE_SIZE_X 280 // 280x224 tiles - better compression efficiency
#define TILE_SIZE_Y 224 // Optimized for TSVM 560x448 (2×2 tiles exactly)
#define TILE_SIZE_Y 224 // Optimised for TSVM 560x448 (2×2 tiles exactly)
#define MAX_DECOMP_LEVELS 6 // Can go deeper: 280→140→70→35→17→8→4, 224→112→56→28→14→7→3
// Simulated overlapping tiles settings for seamless DWT processing
@@ -64,7 +64,7 @@
#define DEFAULT_HEIGHT 448
#define DEFAULT_FPS 30
#define DEFAULT_QUALITY 2
int KEYFRAME_INTERVAL = 60;
int KEYFRAME_INTERVAL = 7; // refresh often because deltas in DWT are more visible than DCT
#define ZSTD_COMPRESSON_LEVEL 15
// Audio/subtitle constants (reused from TEV)
@@ -167,13 +167,13 @@ typedef struct {
int tile_x, tile_y;
} dwt_tile_t;
// DWT subband information for perceptual quantization
// DWT subband information for perceptual quantisation
typedef struct {
int level; // Decomposition level (1 to enc->decomp_levels)
int subband_type; // 0=LL, 1=LH, 2=HL, 3=HH
int coeff_start; // Starting index in linear coefficient array
int coeff_count; // Number of coefficients in this subband
float perceptual_weight; // Quantization multiplier for this subband
float perceptual_weight; // Quantisation multiplier for this subband
} dwt_subband_info_t;
// TAV encoder structure
@@ -215,7 +215,7 @@ typedef struct {
int ictcp_mode; // 0 = YCoCg-R (default), 1 = ICtCp colour space
int intra_only; // Force all tiles to use INTRA mode (disable delta encoding)
int monoblock; // Single DWT tile mode (encode entire frame as one tile)
int perceptual_tuning; // 1 = perceptual quantization (default), 0 = uniform quantization
int perceptual_tuning; // 1 = perceptual quantisation (default), 0 = uniform quantisation
// Frame buffers - ping-pong implementation
uint8_t *frame_rgb[2]; // [0] and [1] alternate between current and previous
@@ -250,7 +250,7 @@ typedef struct {
void *compressed_buffer;
size_t compressed_buffer_size;
// OPTIMIZATION: Pre-allocated buffers to avoid malloc/free per tile
// OPTIMISATION: Pre-allocated buffers to avoid malloc/free per tile
int16_t *reusable_quantised_y;
int16_t *reusable_quantised_co;
int16_t *reusable_quantised_cg;
@@ -313,7 +313,7 @@ static int parse_resolution(const char *res_str, int *width, int *height) {
static void show_usage(const char *program_name);
static tav_encoder_t* create_encoder(void);
static void cleanup_encoder(tav_encoder_t *enc);
static int initialize_encoder(tav_encoder_t *enc);
static int initialise_encoder(tav_encoder_t *enc);
static void rgb_to_ycocg(const uint8_t *rgb, float *y, float *co, float *cg, int width, int height);
static int calculate_max_decomp_levels(int width, int height);
@@ -350,9 +350,9 @@ static void show_usage(const char *program_name) {
printf(" -v, --verbose Verbose output\n");
printf(" -t, --test Test mode: generate solid colour frames\n");
printf(" --lossless Lossless mode: use 5/3 reversible wavelet\n");
printf(" --delta Enable delta encoding (improved compression but noisy picture)\n");
printf(" --no-delta Disable delta encoding (less noisy picture at the cost of larger file)\n");
printf(" --ictcp Use ICtCp colour space instead of YCoCg-R (use when source is in BT.2100)\n");
printf(" --no-perceptual-tuning Disable perceptual quantization (uniform quantization like versions 3/4)\n");
printf(" --no-perceptual-tuning Disable perceptual quantisation\n");
printf(" --encode-limit N Encode only first N frames (useful for testing/analysis)\n");
printf(" --help Show this help\n\n");
@@ -381,10 +381,10 @@ static void show_usage(const char *program_name) {
printf("\n\n");
printf("Features:\n");
printf(" - Single DWT tile (monoblock) encoding for optimal quality\n");
printf(" - Perceptual quantization optimized for human visual system (default)\n");
printf(" - Perceptual quantisation optimised for human visual system (default)\n");
printf(" - Full resolution YCoCg-R/ICtCp colour space\n");
printf(" - Lossless and lossy compression modes\n");
printf(" - Versions 5/6: Perceptual quantization, Versions 3/4: Uniform quantization\n");
printf(" - Versions 5/6: Perceptual quantisation, Versions 3/4: Uniform quantisation\n");
printf("\nExamples:\n");
printf(" %s -i input.mp4 -o output.mv3 # Default settings\n", program_name);
@@ -409,17 +409,17 @@ static tav_encoder_t* create_encoder(void) {
enc->quantiser_y = QUALITY_Y[DEFAULT_QUALITY];
enc->quantiser_co = QUALITY_CO[DEFAULT_QUALITY];
enc->quantiser_cg = QUALITY_CG[DEFAULT_QUALITY];
enc->intra_only = 1;
enc->intra_only = 0;
enc->monoblock = 1; // Default to monoblock mode
enc->perceptual_tuning = 1; // Default to perceptual quantization (versions 5/6)
enc->perceptual_tuning = 1; // Default to perceptual quantisation (versions 5/6)
enc->audio_bitrate = 0; // 0 = use quality table
enc->encode_limit = 0; // Default: no frame limit
return enc;
}
// Initialize encoder resources
static int initialize_encoder(tav_encoder_t *enc) {
// Initialise encoder resources
static int initialise_encoder(tav_encoder_t *enc) {
if (!enc) return -1;
// Automatic decomposition levels for monoblock mode
@@ -444,7 +444,7 @@ static int initialize_encoder(tav_encoder_t *enc) {
enc->frame_rgb[0] = malloc(frame_size * 3);
enc->frame_rgb[1] = malloc(frame_size * 3);
// Initialize ping-pong buffer index and convenience pointers
// Initialise ping-pong buffer index and convenience pointers
enc->frame_buffer_index = 0;
enc->current_frame_rgb = enc->frame_rgb[0];
enc->previous_frame_rgb = enc->frame_rgb[1];
@@ -455,7 +455,7 @@ static int initialize_encoder(tav_encoder_t *enc) {
// Allocate tile structures
enc->tiles = malloc(num_tiles * sizeof(dwt_tile_t));
// Initialize ZSTD compression
// Initialise ZSTD compression
enc->zstd_ctx = ZSTD_createCCtx();
// Calculate maximum possible frame size for ZSTD buffer
@@ -466,7 +466,7 @@ static int initialize_encoder(tav_encoder_t *enc) {
enc->compressed_buffer_size = ZSTD_compressBound(max_frame_size);
enc->compressed_buffer = malloc(enc->compressed_buffer_size);
// OPTIMIZATION: Allocate reusable quantisation buffers
// OPTIMISATION: Allocate reusable quantisation buffers
int coeff_count_per_tile;
if (enc->monoblock) {
// Monoblock mode: entire frame
@@ -605,7 +605,7 @@ static void extract_padded_tile(tav_encoder_t *enc, int tile_x, int tile_y,
const int core_start_x = tile_x * TILE_SIZE_X;
const int core_start_y = tile_y * TILE_SIZE_Y;
// OPTIMIZATION: Process row by row with bulk copying for core region
// OPTIMISATION: Process row by row with bulk copying for core region
for (int py = 0; py < PADDED_TILE_SIZE_Y; py++) {
// Map padded row to source image row
int src_y = core_start_y + py - TILE_MARGIN;
@@ -628,7 +628,7 @@ static void extract_padded_tile(tav_encoder_t *enc, int tile_x, int tile_y,
int core_src_end_x = core_start_x + TILE_SIZE_X;
if (core_src_start_x >= 0 && core_src_end_x <= enc->width) {
// OPTIMIZATION: Bulk copy core region (280 pixels) in one operation
// OPTIMISATION: Bulk copy core region (280 pixels) in one operation
const int src_core_offset = src_row_offset + core_src_start_x;
memcpy(&padded_y[padded_row_offset + core_start_px],
@@ -840,33 +840,33 @@ static float get_perceptual_weight_model2(int level, int subband_type, int is_ch
if (!is_chroma) {
// LUMA CHANNEL: Based on statistical analysis from real video content
if (subband_type == 0) { // LL subband - contains most image energy, preserve carefully
if (level >= 6) return 0.5f; // LL6: High energy but can tolerate moderate quantization (range up to 22K)
if (level >= 6) return 0.5f; // LL6: High energy but can tolerate moderate quantisation (range up to 22K)
if (level >= 5) return 0.7f; // LL5: Good preservation
return 0.9f; // Lower LL levels: Fine preservation
} else if (subband_type == 1) { // LH subband - horizontal details (human eyes more sensitive)
if (level >= 6) return 0.8f; // LH6: Significant coefficients (max ~500), preserve well
if (level >= 5) return 1.0f; // LH5: Moderate coefficients (max ~600)
if (level >= 4) return 1.2f; // LH4: Small coefficients (max ~50)
if (level >= 3) return 1.6f; // LH3: Very small coefficients, can quantize more
if (level >= 3) return 1.6f; // LH3: Very small coefficients, can quantise more
if (level >= 2) return 2.0f; // LH2: Minimal impact
return 2.5f; // LH1: Least important
} else if (subband_type == 2) { // HL subband - vertical details (less sensitive due to HVS characteristics)
if (level >= 6) return 1.0f; // HL6: Can quantize more aggressively than LH6
if (level >= 5) return 1.2f; // HL5: Standard quantization
if (level >= 6) return 1.0f; // HL6: Can quantise more aggressively than LH6
if (level >= 5) return 1.2f; // HL5: Standard quantisation
if (level >= 4) return 1.5f; // HL4: Notable range but less critical
if (level >= 3) return 2.0f; // HL3: Can tolerate more quantization
if (level >= 3) return 2.0f; // HL3: Can tolerate more quantisation
if (level >= 2) return 2.5f; // HL2: Less important
return 3.5f; // HL1: Most aggressive for vertical details
} else { // HH subband - diagonal details (least important for HVS)
if (level >= 6) return 1.2f; // HH6: Preserve some diagonal detail
if (level >= 5) return 1.6f; // HH5: Can quantize aggressively
if (level >= 5) return 1.6f; // HH5: Can quantise aggressively
if (level >= 4) return 2.0f; // HH4: Very aggressive
if (level >= 3) return 2.8f; // HH3: Minimal preservation
if (level >= 2) return 3.5f; // HH2: Maximum compression
return 5.0f; // HH1: Most aggressive quantization
return 5.0f; // HH1: Most aggressive quantisation
}
} else {
// CHROMA CHANNELS: Less critical for human perception, more aggressive quantization
// CHROMA CHANNELS: Less critical for human perception, more aggressive quantisation
// strategy: mimic 4:2:2 chroma subsampling
if (subband_type == 0) { // LL chroma - still important but less than luma
return 1.0f;
@@ -926,7 +926,7 @@ static float get_perceptual_weight(tav_encoder_t *enc, int level, int subband_ty
// HH subband - diagonal details
else return perceptual_model3_HH(LH, HL) * (level == 2 ? TWO_PIXEL_DETAILER : level == 3 ? FOUR_PIXEL_DETAILER : 1.0f);
} else {
// CHROMA CHANNELS: Less critical for human perception, more aggressive quantization
// CHROMA CHANNELS: Less critical for human perception, more aggressive quantisation
// strategy: more horizontal detail
//// mimic 4:4:0 (you heard that right!) chroma subsampling (4:4:4 for higher q, 4:2:0 for lower q)
//// because our eyes are apparently sensitive to horizontal chroma diff as well?
@@ -991,13 +991,13 @@ static float get_perceptual_weight_for_position(tav_encoder_t *enc, int linear_i
return 1.0f;
}
// Apply perceptual quantization per-coefficient (same loop as uniform but with spatial weights)
// Apply perceptual quantisation per-coefficient (same loop as uniform but with spatial weights)
static void quantise_dwt_coefficients_perceptual_per_coeff(tav_encoder_t *enc,
float *coeffs, int16_t *quantised, int size,
int base_quantizer, int width, int height,
int base_quantiser, int width, int height,
int decomp_levels, int is_chroma, int frame_count) {
// EXACTLY the same approach as uniform quantization but apply weight per coefficient
float effective_base_q = base_quantizer;
// EXACTLY the same approach as uniform quantisation but apply weight per coefficient
float effective_base_q = base_quantiser;
effective_base_q = FCLAMP(effective_base_q, 1.0f, 255.0f);
for (int i = 0; i < size; i++) {
@@ -1090,7 +1090,7 @@ static size_t serialise_tile_data(tav_encoder_t *enc, int tile_x, int tile_y,
const int tile_size = enc->monoblock ?
(enc->width * enc->height) : // Monoblock mode: full frame
(PADDED_TILE_SIZE_X * PADDED_TILE_SIZE_Y); // Standard mode: padded tiles
// OPTIMIZATION: Use pre-allocated buffers instead of malloc/free per tile
// OPTIMISATION: Use pre-allocated buffers instead of malloc/free per tile
int16_t *quantised_y = enc->reusable_quantised_y;
int16_t *quantised_co = enc->reusable_quantised_co;
int16_t *quantised_cg = enc->reusable_quantised_cg;
@@ -1109,12 +1109,12 @@ static size_t serialise_tile_data(tav_encoder_t *enc, int tile_x, int tile_y,
if (mode == TAV_MODE_INTRA) {
// INTRA mode: quantise coefficients directly and store for future reference
if (enc->perceptual_tuning) {
// Perceptual quantization: EXACTLY like uniform but with per-coefficient weights
// Perceptual quantisation: EXACTLY like uniform but with per-coefficient weights
quantise_dwt_coefficients_perceptual_per_coeff(enc, (float*)tile_y_data, quantised_y, tile_size, this_frame_qY, enc->width, enc->height, enc->decomp_levels, 0, enc->frame_count);
quantise_dwt_coefficients_perceptual_per_coeff(enc, (float*)tile_co_data, quantised_co, tile_size, this_frame_qCo, enc->width, enc->height, enc->decomp_levels, 1, enc->frame_count);
quantise_dwt_coefficients_perceptual_per_coeff(enc, (float*)tile_cg_data, quantised_cg, tile_size, this_frame_qCg, enc->width, enc->height, enc->decomp_levels, 1, enc->frame_count);
} else {
// Legacy uniform quantization
// Legacy uniform quantisation
quantise_dwt_coefficients((float*)tile_y_data, quantised_y, tile_size, this_frame_qY);
quantise_dwt_coefficients((float*)tile_co_data, quantised_co, tile_size, this_frame_qCo);
quantise_dwt_coefficients((float*)tile_cg_data, quantised_cg, tile_size, this_frame_qCg);
@@ -1147,123 +1147,22 @@ static size_t serialise_tile_data(tav_encoder_t *enc, int tile_x, int tile_y,
delta_cg[i] = tile_cg_data[i] - prev_cg[i];
}
// Quantise the deltas with per-coefficient perceptual quantization
if (enc->perceptual_tuning) {
quantise_dwt_coefficients_perceptual_per_coeff(enc, delta_y, quantised_y, tile_size, this_frame_qY, enc->width, enc->height, enc->decomp_levels, 0, 0);
quantise_dwt_coefficients_perceptual_per_coeff(enc, delta_co, quantised_co, tile_size, this_frame_qCo, enc->width, enc->height, enc->decomp_levels, 1, 0);
quantise_dwt_coefficients_perceptual_per_coeff(enc, delta_cg, quantised_cg, tile_size, this_frame_qCg, enc->width, enc->height, enc->decomp_levels, 1, 0);
} else {
// Legacy uniform delta quantization
quantise_dwt_coefficients(delta_y, quantised_y, tile_size, this_frame_qY);
quantise_dwt_coefficients(delta_co, quantised_co, tile_size, this_frame_qCo);
quantise_dwt_coefficients(delta_cg, quantised_cg, tile_size, this_frame_qCg);
// Quantise the deltas with uniform quantisation (perceptual tuning is for original coefficients, not deltas)
quantise_dwt_coefficients(delta_y, quantised_y, tile_size, this_frame_qY);
quantise_dwt_coefficients(delta_co, quantised_co, tile_size, this_frame_qCo);
quantise_dwt_coefficients(delta_cg, quantised_cg, tile_size, this_frame_qCg);
// Reconstruct coefficients like decoder will (previous + uniform_dequantised_delta)
for (int i = 0; i < tile_size; i++) {
float dequant_delta_y = (float)quantised_y[i] * this_frame_qY;
float dequant_delta_co = (float)quantised_co[i] * this_frame_qCo;
float dequant_delta_cg = (float)quantised_cg[i] * this_frame_qCg;
prev_y[i] = prev_y[i] + dequant_delta_y;
prev_co[i] = prev_co[i] + dequant_delta_co;
prev_cg[i] = prev_cg[i] + dequant_delta_cg;
}
// Reconstruct coefficients like decoder will (previous + dequantised_delta)
if (enc->perceptual_tuning) {
// Apply 2D perceptual dequantization using same logic as quantization
// First, apply uniform dequantization baseline
for (int i = 0; i < tile_size; i++) {
prev_y[i] = prev_y[i] + ((float)quantised_y[i] * (float)this_frame_qY);
prev_co[i] = prev_co[i] + ((float)quantised_co[i] * (float)this_frame_qCo);
prev_cg[i] = prev_cg[i] + ((float)quantised_cg[i] * (float)this_frame_qCg);
}
// Then apply perceptual correction by re-dequantizing specific subbands
for (int level = 1; level <= enc->decomp_levels; level++) {
int level_width = enc->width >> (enc->decomp_levels - level + 1);
int level_height = enc->height >> (enc->decomp_levels - level + 1);
// Skip if subband is too small
if (level_width < 1 || level_height < 1) continue;
// Get perceptual weights for this level
float lh_weight_y = get_perceptual_weight(enc, level, 1, 0, enc->decomp_levels);
float hl_weight_y = get_perceptual_weight(enc, level, 2, 0, enc->decomp_levels);
float hh_weight_y = get_perceptual_weight(enc, level, 3, 0, enc->decomp_levels);
float lh_weight_co = get_perceptual_weight(enc, level, 1, 1, enc->decomp_levels);
float hl_weight_co = get_perceptual_weight(enc, level, 2, 1, enc->decomp_levels);
float hh_weight_co = get_perceptual_weight(enc, level, 3, 1, enc->decomp_levels);
// Correct LH subband (top-right quadrant)
for (int y = 0; y < level_height; y++) {
for (int x = level_width; x < level_width * 2; x++) {
if (y < enc->height && x < enc->width) {
int idx = y * enc->width + x;
// Remove uniform dequantization and apply perceptual
prev_y[idx] -= ((float)quantised_y[idx] * (float)this_frame_qY);
prev_y[idx] += ((float)quantised_y[idx] * ((float)this_frame_qY * lh_weight_y));
prev_co[idx] -= ((float)quantised_co[idx] * (float)this_frame_qCo);
prev_co[idx] += ((float)quantised_co[idx] * ((float)this_frame_qCo * lh_weight_co));
prev_cg[idx] -= ((float)quantised_cg[idx] * (float)this_frame_qCg);
prev_cg[idx] += ((float)quantised_cg[idx] * ((float)this_frame_qCg * lh_weight_co));
}
}
}
// Correct HL subband (bottom-left quadrant)
for (int y = level_height; y < level_height * 2; y++) {
for (int x = 0; x < level_width; x++) {
if (y < enc->height && x < enc->width) {
int idx = y * enc->width + x;
prev_y[idx] -= ((float)quantised_y[idx] * (float)this_frame_qY);
prev_y[idx] += ((float)quantised_y[idx] * ((float)this_frame_qY * hl_weight_y));
prev_co[idx] -= ((float)quantised_co[idx] * (float)this_frame_qCo);
prev_co[idx] += ((float)quantised_co[idx] * ((float)this_frame_qCo * hl_weight_co));
prev_cg[idx] -= ((float)quantised_cg[idx] * (float)this_frame_qCg);
prev_cg[idx] += ((float)quantised_cg[idx] * ((float)this_frame_qCg * hl_weight_co));
}
}
}
// Correct HH subband (bottom-right quadrant)
for (int y = level_height; y < level_height * 2; y++) {
for (int x = level_width; x < level_width * 2; x++) {
if (y < enc->height && x < enc->width) {
int idx = y * enc->width + x;
prev_y[idx] -= ((float)quantised_y[idx] * (float)this_frame_qY);
prev_y[idx] += ((float)quantised_y[idx] * ((float)this_frame_qY * hh_weight_y));
prev_co[idx] -= ((float)quantised_co[idx] * (float)this_frame_qCo);
prev_co[idx] += ((float)quantised_co[idx] * ((float)this_frame_qCo * hh_weight_co));
prev_cg[idx] -= ((float)quantised_cg[idx] * (float)this_frame_qCg);
prev_cg[idx] += ((float)quantised_cg[idx] * ((float)this_frame_qCg * hh_weight_co));
}
}
}
}
// Finally, correct LL subband (top-left corner at finest level)
int ll_width = enc->width >> enc->decomp_levels;
int ll_height = enc->height >> enc->decomp_levels;
float ll_weight_y = get_perceptual_weight(enc, enc->decomp_levels, 0, 0, enc->decomp_levels);
float ll_weight_co = get_perceptual_weight(enc, enc->decomp_levels, 0, 1, enc->decomp_levels);
for (int y = 0; y < ll_height; y++) {
for (int x = 0; x < ll_width; x++) {
if (y < enc->height && x < enc->width) {
int idx = y * enc->width + x;
prev_y[idx] -= ((float)quantised_y[idx] * (float)this_frame_qY);
prev_y[idx] += ((float)quantised_y[idx] * ((float)this_frame_qY * ll_weight_y));
prev_co[idx] -= ((float)quantised_co[idx] * (float)this_frame_qCo);
prev_co[idx] += ((float)quantised_co[idx] * ((float)this_frame_qCo * ll_weight_co));
prev_cg[idx] -= ((float)quantised_cg[idx] * (float)this_frame_qCg);
prev_cg[idx] += ((float)quantised_cg[idx] * ((float)this_frame_qCg * ll_weight_co));
}
}
}
} else {
// Legacy uniform dequantization
for (int i = 0; i < tile_size; i++) {
float dequant_delta_y = (float)quantised_y[i] * this_frame_qY;
float dequant_delta_co = (float)quantised_co[i] * this_frame_qCo;
float dequant_delta_cg = (float)quantised_cg[i] * this_frame_qCg;
prev_y[i] = prev_y[i] + dequant_delta_y;
prev_co[i] = prev_co[i] + dequant_delta_co;
prev_cg[i] = prev_cg[i] + dequant_delta_cg;
}
}
free(delta_y);
free(delta_co);
free(delta_cg);
@@ -1283,7 +1182,7 @@ static size_t serialise_tile_data(tav_encoder_t *enc, int tile_x, int tile_y,
memcpy(buffer + offset, quantised_co, tile_size * sizeof(int16_t)); offset += tile_size * sizeof(int16_t);
memcpy(buffer + offset, quantised_cg, tile_size * sizeof(int16_t)); offset += tile_size * sizeof(int16_t);
// OPTIMIZATION: No need to free - using pre-allocated reusable buffers
// OPTIMISATION: No need to free - using pre-allocated reusable buffers
return offset;
}
@@ -1429,11 +1328,11 @@ static size_t compress_and_write_frame(tav_encoder_t *enc, uint8_t packet_type)
static void rgb_to_ycocg(const uint8_t *rgb, float *y, float *co, float *cg, int width, int height) {
const int total_pixels = width * height;
// OPTIMIZATION: Process 4 pixels at a time for better cache utilization
// OPTIMISATION: Process 4 pixels at a time for better cache utilisation
int i = 0;
const int simd_end = (total_pixels / 4) * 4;
// Vectorized processing for groups of 4 pixels
// Vectorised processing for groups of 4 pixels
for (i = 0; i < simd_end; i += 4) {
// Load 4 RGB triplets (12 bytes) at once
const uint8_t *rgb_ptr = &rgb[i * 3];
@@ -1471,12 +1370,12 @@ static void rgb_to_ycocg(const uint8_t *rgb, float *y, float *co, float *cg, int
static inline int iround(double v) { return (int)floor(v + 0.5); }
// ---------------------- sRGB gamma helpers ----------------------
static inline double srgb_linearize(double val) {
static inline double srgb_linearise(double val) {
if (val <= 0.04045) return val / 12.92;
return pow((val + 0.055) / 1.055, 2.4);
}
static inline double srgb_unlinearize(double val) {
static inline double srgb_unlinearise(double val) {
if (val <= 0.0031308) return 12.92 * val;
return 1.055 * pow(val, 1.0/2.4) - 0.055;
}
@@ -1541,10 +1440,10 @@ static const double M_ICTCP_TO_LMSPRIME[3][3] = {
void srgb8_to_ictcp_hlg(uint8_t r8, uint8_t g8, uint8_t b8,
double *out_I, double *out_Ct, double *out_Cp)
{
// 1) linearize sRGB to 0..1
double r = srgb_linearize((double)r8 / 255.0);
double g = srgb_linearize((double)g8 / 255.0);
double b = srgb_linearize((double)b8 / 255.0);
// 1) linearise sRGB to 0..1
double r = srgb_linearise((double)r8 / 255.0);
double g = srgb_linearise((double)g8 / 255.0);
double b = srgb_linearise((double)b8 / 255.0);
// 2) linear RGB -> LMS (single 3x3 multiply)
double L = M_RGB_TO_LMS[0][0]*r + M_RGB_TO_LMS[0][1]*g + M_RGB_TO_LMS[0][2]*b;
@@ -1590,9 +1489,9 @@ void ictcp_hlg_to_srgb8(double I8, double Ct8, double Cp8,
double b_lin = M_LMS_TO_RGB[2][0]*L + M_LMS_TO_RGB[2][1]*M + M_LMS_TO_RGB[2][2]*S;
// 4) gamma encode and convert to 0..255 with center-of-bin rounding
double r = srgb_unlinearize(r_lin);
double g = srgb_unlinearize(g_lin);
double b = srgb_unlinearize(b_lin);
double r = srgb_unlinearise(r_lin);
double g = srgb_unlinearise(g_lin);
double b = srgb_unlinearise(b_lin);
*r8 = (uint8_t)iround(FCLAMP(r * 255.0, 0.0, 255.0));
*g8 = (uint8_t)iround(FCLAMP(g * 255.0, 0.0, 255.0));
@@ -1975,7 +1874,7 @@ static subtitle_entry_t* parse_srt_file(const char *filename, int fps) {
continue;
}
// Initialize text buffer
// Initialise text buffer
text_buffer_size = 256;
text_buffer = malloc(text_buffer_size);
if (!text_buffer) {
@@ -2429,7 +2328,7 @@ static int process_audio(tav_encoder_t *enc, int frame_num, FILE *output) {
return 1;
}
// Initialize packet size on first frame
// Initialise packet size on first frame
if (frame_num == 0) {
uint8_t header[4];
if (fread(header, 1, 4, enc->mp2_file) != 4) return 1;
@@ -2644,7 +2543,7 @@ int main(int argc, char *argv[]) {
{"fps", required_argument, 0, 'f'},
{"quality", required_argument, 0, 'q'},
{"quantiser", required_argument, 0, 'Q'},
{"quantizer", required_argument, 0, 'Q'},
{"quantiser", required_argument, 0, 'Q'},
// {"wavelet", required_argument, 0, 'w'},
{"bitrate", required_argument, 0, 'b'},
{"arate", required_argument, 0, 1400},
@@ -2653,7 +2552,7 @@ int main(int argc, char *argv[]) {
{"verbose", no_argument, 0, 'v'},
{"test", no_argument, 0, 't'},
{"lossless", no_argument, 0, 1000},
{"delta", no_argument, 0, 1006},
{"no-delta", no_argument, 0, 1006},
{"ictcp", no_argument, 0, 1005},
{"no-perceptual-tuning", no_argument, 0, 1007},
{"encode-limit", required_argument, 0, 1008},
@@ -2725,7 +2624,7 @@ int main(int argc, char *argv[]) {
enc->ictcp_mode = 1;
break;
case 1006: // --intra-only
enc->intra_only = 0;
enc->intra_only = 1;
break;
case 1007: // --no-perceptual-tuning
enc->perceptual_tuning = 0;
@@ -2777,8 +2676,8 @@ int main(int argc, char *argv[]) {
return 1;
}
if (initialize_encoder(enc) != 0) {
fprintf(stderr, "Error: Failed to initialize encoder\n");
if (initialise_encoder(enc) != 0) {
fprintf(stderr, "Error: Failed to initialise encoder\n");
cleanup_encoder(enc);
return 1;
}
@@ -2790,7 +2689,7 @@ int main(int argc, char *argv[]) {
printf("Wavelet: %s\n", enc->wavelet_filter ? "9/7 irreversible" : "5/3 reversible");
printf("Decomposition levels: %d\n", enc->decomp_levels);
printf("Colour space: %s\n", enc->ictcp_mode ? "ICtCp" : "YCoCg-R");
printf("Quantization: %s\n", enc->perceptual_tuning ? "Perceptual (HVS-optimized)" : "Uniform (legacy)");
printf("Quantisation: %s\n", enc->perceptual_tuning ? "Perceptual (HVS-optimised)" : "Uniform (legacy)");
if (enc->ictcp_mode) {
printf("Base quantiser: I=%d, Ct=%d, Cp=%d\n", enc->quantiser_y, enc->quantiser_co, enc->quantiser_cg);
} else {
@@ -2875,11 +2774,13 @@ int main(int argc, char *argv[]) {
int count_iframe = 0;
int count_pframe = 0;
KEYFRAME_INTERVAL = enc->output_fps >> 2; // refresh often because deltas in DWT are more visible than DCT
while (continue_encoding) {
// Check encode limit if specified
if (enc->encode_limit > 0 && frame_count >= enc->encode_limit) {
printf("Reached encode limit of %d frames, finalizing...\n", enc->encode_limit);
printf("Reached encode limit of %d frames, finalising...\n", enc->encode_limit);
continue_encoding = 0;
break;
}
@@ -3095,7 +2996,7 @@ static void cleanup_encoder(tav_encoder_t *enc) {
free(enc->compressed_buffer);
free(enc->mp2_buffer);
// OPTIMIZATION: Free reusable quantisation buffers
// OPTIMISATION: Free reusable quantisation buffers
free(enc->reusable_quantised_y);
free(enc->reusable_quantised_co);
free(enc->reusable_quantised_cg);