X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=qdc.cpp;h=5a4a9d506195586ec9c56d2893621c0f69379233;hb=df875b27feed0684ef6b469ceda368fdbf2a2043;hp=556a8a5d541315a54d6bddf332cdd746a5c1769a;hpb=34138d5b1a1302a7a1050fd46d2fb95c0186140a;p=narabu

diff --git a/qdc.cpp b/qdc.cpp
index 556a8a5..5a4a9d5 100644
--- a/qdc.cpp
+++ b/qdc.cpp
@@ -719,16 +719,35 @@ int main(int argc, char **argv)
 		chroma_energy / (WIDTH * HEIGHT), chroma_energy_pred / (WIDTH * HEIGHT));
 #endif
 
-	// DC coefficient pred from the right to left
-	for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
-		for (unsigned xb = 0; xb < WIDTH - 8; xb += 8) {
-			coeff_y[yb * WIDTH + xb] -= coeff_y[yb * WIDTH + (xb + 8)];
+	// DC coefficient pred from the right to left (within each slice)
+	for (unsigned block_idx = 0; block_idx < NUM_BLOCKS; block_idx += 320) {
+		int prev_k = 128;
+
+		for (unsigned subblock_idx = 320; subblock_idx --> 0; ) {
+			unsigned yb = (block_idx + subblock_idx) / WIDTH_BLOCKS;
+			unsigned xb = (block_idx + subblock_idx) % WIDTH_BLOCKS;
+			int k = coeff_y[(yb * 8) * WIDTH + (xb * 8)];
+
+			coeff_y[(yb * 8) * WIDTH + (xb * 8)] = k - prev_k;
+
+			prev_k = k;
 		}
 	}
-	for (unsigned yb = 0; yb < HEIGHT; yb += 8) {
-		for (unsigned xb = 0; xb < WIDTH/2 - 8; xb += 8) {
-			coeff_cb[yb * WIDTH/2 + xb] -= coeff_cb[yb * WIDTH/2 + (xb + 8)];
-			coeff_cr[yb * WIDTH/2 + xb] -= coeff_cr[yb * WIDTH/2 + (xb + 8)];
+	for (unsigned block_idx = 0; block_idx < NUM_BLOCKS_CHROMA; block_idx += 320) {
+		int prev_k_cb = 0;
+		int prev_k_cr = 0;
+
+		for (unsigned subblock_idx = 320; subblock_idx --> 0; ) {
+			unsigned yb = (block_idx + subblock_idx) / WIDTH_BLOCKS_CHROMA;
+			unsigned xb = (block_idx + subblock_idx) % WIDTH_BLOCKS_CHROMA;
+			int k_cb = coeff_cb[(yb * 8) * WIDTH/2 + (xb * 8)];
+			int k_cr = coeff_cr[(yb * 8) * WIDTH/2 + (xb * 8)];
+
+			coeff_cb[(yb * 8) * WIDTH/2 + (xb * 8)] = k_cb - prev_k_cb;
+			coeff_cr[(yb * 8) * WIDTH/2 + (xb * 8)] = k_cr - prev_k_cr;
+
+			prev_k_cb = k_cb;
+			prev_k_cr = k_cr;
 		}
 	}