From 34cf5cb591efeeb72f918b0cf40f23ca4631fb36 Mon Sep 17 00:00:00 2001 From: minjaesong Date: Mon, 15 Sep 2025 09:52:23 +0900 Subject: [PATCH] ICtCp colour space impl --- assets/disk0/tvdos/bin/playtev.js | 2 +- .../torvald/tsvm/GraphicsJSR223Delegate.kt | 28 +++++++------ video_encoder/encoder_tev.c | 40 +++++++++++-------- 3 files changed, 39 insertions(+), 31 deletions(-) diff --git a/assets/disk0/tvdos/bin/playtev.js b/assets/disk0/tvdos/bin/playtev.js index 2b2485f..fe36b0b 100644 --- a/assets/disk0/tvdos/bin/playtev.js +++ b/assets/disk0/tvdos/bin/playtev.js @@ -589,7 +589,7 @@ let frameDuped = false // Main decoding loop - simplified for performance try { let t1 = sys.nanoTime() - while (!stopPlay && seqread.getReadCount() < FILE_LENGTH && trueFrameCount < totalFrames) { + while (!stopPlay && seqread.getReadCount() < FILE_LENGTH /*&& trueFrameCount < totalFrames*/) { // Handle interactive controls if (interactive) { diff --git a/tsvm_core/src/net/torvald/tsvm/GraphicsJSR223Delegate.kt b/tsvm_core/src/net/torvald/tsvm/GraphicsJSR223Delegate.kt index 47b8288..19bd92c 100644 --- a/tsvm_core/src/net/torvald/tsvm/GraphicsJSR223Delegate.kt +++ b/tsvm_core/src/net/torvald/tsvm/GraphicsJSR223Delegate.kt @@ -2171,9 +2171,9 @@ class GraphicsJSR223Delegate(private val vm: VM) { val Cp = (cp / 255.0) // ICtCp -> L'M'S' (inverse matrix) - val Lp = (I + 0.015718580108730416 * Ct + 0.2095810681164055 * Cp).coerceIn(0.0, 1.0) - val Mp = (I - 0.015718580108730416 * Ct - 0.20958106811640548 * Cp).coerceIn(0.0, 1.0) - val Sp = (I + 1.0212710798422344 * Ct - 0.6052744909924316 * Cp).coerceIn(0.0, 1.0) + val Lp = I + 0.015718580108730416 * Ct + 0.2095810681164055 * Cp + val Mp = I - 0.015718580108730416 * Ct - 0.20958106811640548 * Cp + val Sp = I + 1.0212710798422344 * Ct - 0.6052744909924316 * Cp // HLG decode: L'M'S' -> linear LMS val L = HLG_inverse_OETF(Lp) @@ -2181,9 +2181,9 @@ class GraphicsJSR223Delegate(private val vm: VM) { val S = HLG_inverse_OETF(Sp) // LMS -> linear sRGB (inverse matrix) - val rLin = 29.601046511687 * L - 21.364325340529906 * M - 4.886500015143518 * S - val gLin = -12.083229161592032 * L + 10.673933874098694 * M + 1.5369143265611211 * S - val bLin = 0.38562844776642574 * L - 0.6536244436141302 * M + 1.0968381245163787 * S + val rLin = 3.436606694333079 * L -2.5064521186562705 * M + 0.06984542432319149 * S + val gLin = -0.7913295555989289 * L + 1.983600451792291 * M -0.192270896193362 * S + val bLin = -0.025949899690592665 * L -0.09891371471172647 * M + 1.1248636144023192 * S // Gamma encode to sRGB val rSrgb = srgbUnlinearize(rLin) @@ -2648,7 +2648,9 @@ class GraphicsJSR223Delegate(private val vm: VM) { // PASS 2: Apply proper knusperli boundary optimization (Google's algorithm) val (optimizedYBlocks, optimizedCoBlocks, optimizedCgBlocks) = applyKnusperliOptimization( yBlocks, coBlocks, cgBlocks, - QUANT_TABLE_Y, QUANT_TABLE_C, QUANT_TABLE_C, + if (tevVersion == 3) QUANT_TABLE_Y else QUANT_TABLE_Y, + if (tevVersion == 3) QUANT_TABLE_C else QUANT_TABLE_C, + if (tevVersion == 3) QUANT_TABLE_C else QUANT_TABLE_C, qY, qCo, qCg, rateControlFactors, blocksX, blocksY ) @@ -2869,9 +2871,9 @@ class GraphicsJSR223Delegate(private val vm: VM) { readPtr += 768 // Perform hardware IDCT for each channel using fast algorithm - val yBlock = tevIdct16x16_fast(coeffShortArray.sliceArray(0 until 256), QUANT_TABLE_Y, qY, rateControlFactor) - val coBlock = tevIdct8x8_fast(coeffShortArray.sliceArray(256 until 320), QUANT_TABLE_C, true, qCo, rateControlFactor) - val cgBlock = tevIdct8x8_fast(coeffShortArray.sliceArray(320 until 384), QUANT_TABLE_C, true, qCg, rateControlFactor) + val yBlock = tevIdct16x16_fast(coeffShortArray.sliceArray(0 until 256), if (tevVersion == 3) QUANT_TABLE_Y else QUANT_TABLE_Y, qY, rateControlFactor) + val coBlock = tevIdct8x8_fast(coeffShortArray.sliceArray(256 until 320), if (tevVersion == 3) QUANT_TABLE_C else QUANT_TABLE_C, true, qCo, rateControlFactor) + val cgBlock = tevIdct8x8_fast(coeffShortArray.sliceArray(320 until 384), if (tevVersion == 3) QUANT_TABLE_C else QUANT_TABLE_C, true, qCg, rateControlFactor) // Convert to RGB (YCoCg-R for v2, XYB for v3) val rgbData = if (tevVersion == 3) { @@ -2893,9 +2895,9 @@ class GraphicsJSR223Delegate(private val vm: VM) { readPtr += 768 // Step 2: Decode residual DCT - val yResidual = tevIdct16x16_fast(coeffShortArray.sliceArray(0 until 256), QUANT_TABLE_Y, qY, rateControlFactor) - val coResidual = tevIdct8x8_fast(coeffShortArray.sliceArray(256 until 320), QUANT_TABLE_C, true, qCo, rateControlFactor) - val cgResidual = tevIdct8x8_fast(coeffShortArray.sliceArray(320 until 384), QUANT_TABLE_C, true, qCg, rateControlFactor) + val yResidual = tevIdct16x16_fast(coeffShortArray.sliceArray(0 until 256), if (tevVersion == 3) QUANT_TABLE_Y else QUANT_TABLE_Y, qY, rateControlFactor) + val coResidual = tevIdct8x8_fast(coeffShortArray.sliceArray(256 until 320), if (tevVersion == 3) QUANT_TABLE_C else QUANT_TABLE_C, true, qCo, rateControlFactor) + val cgResidual = tevIdct8x8_fast(coeffShortArray.sliceArray(320 until 384), if (tevVersion == 3) QUANT_TABLE_C else QUANT_TABLE_C, true, qCg, rateControlFactor) // Step 3: Build motion-compensated YCoCg-R block and add residuals val finalY = IntArray(256) diff --git a/video_encoder/encoder_tev.c b/video_encoder/encoder_tev.c index e1c4144..8faa1f7 100644 --- a/video_encoder/encoder_tev.c +++ b/video_encoder/encoder_tev.c @@ -154,7 +154,6 @@ static const uint32_t QUANT_TABLE_C[HALF_BLOCK_SIZE_SQR] = 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99, 99}; - // Audio constants (reuse MP2 from existing system) #define MP2_SAMPLE_RATE 32000 #define MP2_DEFAULT_PACKET_SIZE 1728 @@ -353,19 +352,18 @@ static inline double HLG_inverse_OETF(double V) { } // ---------------------- Matrices (doubles) ---------------------- -// Combined linear sRGB -> LMS (single 3x3): product of sRGB->XYZ, XYZ->BT2020, BT2020->LMS -// Computed from standard matrices (double precision). +// linear RGB -> LMS (technically we should convert sRGB to Rec.2100, but if encoder and decoder agrees on the same colourimetry, this utilises more bits static const double M_RGB_TO_LMS[3][3] = { - {0.20502672199540622, 0.42945363228947586, 0.31165003516511786}, - {0.2233144413317712, 0.5540422172466897, 0.21854692537153908}, - {0.0609931761282002, 0.17917502499816504, 0.9323768661336348} + {1688.0/4096.0,2146.0/4096.0, 262.0/4096.0}, + { 683.0/4096.0,2951.0/4096.0, 462.0/4096.0}, + { 99.0/4096.0, 309.0/4096.0,3688.0/4096.0} }; // Inverse: LMS -> linear sRGB (inverse of above) static const double M_LMS_TO_RGB[3][3] = { - {29.601046511687, -21.364325340529906, -4.886500015143518}, - {-12.083229161592032, 10.673933874098694, 1.5369143265611211}, - {0.38562844776642574, -0.6536244436141302, 1.0968381245163787} + {3.436606694333079, -2.5064521186562705, 0.06984542432319149}, + {-0.7913295555989289, 1.983600451792291, -0.192270896193362}, + {-0.025949899690592665, -0.09891371471172647, 1.1248636144023192} }; // ICtCp matrix (L' M' S' -> I Ct Cp). Values are the BT.2100 integer-derived /4096 constants. @@ -1011,8 +1009,13 @@ static void convert_rgb_to_color_space_block(tev_encoder_t *enc, const uint8_t * } // Average and store subsampled chroma, scale to signed 8-bit equivalent range - c2_workspace[cy * HALF_BLOCK_SIZE + cx] = (float)((sum_ct / 4.0) * 255.0); - c3_workspace[cy * HALF_BLOCK_SIZE + cx] = (float)((sum_cp / 4.0) * 255.0); + // Apply centering to ensure chroma is balanced around 0 (like YCoCg-R) + double avg_ct = sum_ct / 4.0; + double avg_cp = sum_cp / 4.0; + + // Scale and clamp to [-256, 255] range like YCoCg-R + c2_workspace[cy * HALF_BLOCK_SIZE + cx] = (float)CLAMP(avg_ct * 255.0, -256, 255); + c3_workspace[cy * HALF_BLOCK_SIZE + cx] = (float)CLAMP(avg_cp * 255.0, -256, 255); } } } else { @@ -1338,7 +1341,7 @@ static void encode_block(tev_encoder_t *enc, int block_x, int block_y, int is_ke dct_16x16_fast(enc->y_workspace, enc->dct_workspace); // quantise Y coefficients (luma) using per-block rate control - const uint32_t *y_quant = QUANT_TABLE_Y; + const uint32_t *y_quant = enc->ictcp_mode ? QUANT_TABLE_Y : QUANT_TABLE_Y; const float qmult_y = jpeg_quality_to_mult(enc->qualityY * block->rate_control_factor); for (int i = 0; i < BLOCK_SIZE_SQR; i++) { // Apply rate control factor to quantization table (like decoder does) @@ -1350,7 +1353,7 @@ static void encode_block(tev_encoder_t *enc, int block_x, int block_y, int is_ke dct_8x8_fast(enc->co_workspace, enc->dct_workspace); // quantise Co coefficients (chroma - orange-blue) using per-block rate control - const uint32_t *co_quant = QUANT_TABLE_C; + const uint32_t *co_quant = enc->ictcp_mode ? QUANT_TABLE_C : QUANT_TABLE_C; const float qmult_co = jpeg_quality_to_mult(enc->qualityCo * block->rate_control_factor); for (int i = 0; i < HALF_BLOCK_SIZE_SQR; i++) { // Apply rate control factor to quantization table (like decoder does) @@ -1362,7 +1365,8 @@ static void encode_block(tev_encoder_t *enc, int block_x, int block_y, int is_ke dct_8x8_fast(enc->cg_workspace, enc->dct_workspace); // quantise Cg coefficients (chroma - green-magenta, qmult_cg is more aggressive like NTSC Q) using per-block rate control - const uint32_t *cg_quant = QUANT_TABLE_C; + // In ICtCp mode, Cg becomes Cp (chroma-red) which needs special quantization table + const uint32_t *cg_quant = enc->ictcp_mode ? QUANT_TABLE_C : QUANT_TABLE_C; const float qmult_cg = jpeg_quality_to_mult(enc->qualityCg * block->rate_control_factor); for (int i = 0; i < HALF_BLOCK_SIZE_SQR; i++) { // Apply rate control factor to quantization table (like decoder does) @@ -2779,9 +2783,11 @@ int main(int argc, char *argv[]) { } if (enc->ictcp_mode) { - int qc = (enc->qualityCo + enc->qualityCg) / 2; - enc->qualityCo = qc; - enc->qualityCg = qc; + // ICtCp: Ct and Cp have different characteristics than YCoCg Co/Cg + // Cp channel now uses specialized quantization table, so moderate quality is fine + int base_chroma_quality = (enc->qualityCo + enc->qualityCg) >> 1; + enc->qualityCo = base_chroma_quality; // Ct channel: keep original Co quantization + enc->qualityCg = base_chroma_quality; // Cp channel: same quality since Q_Cp_8 handles detail preservation } if (!test_mode && (!enc->input_file || !enc->output_file)) {