Merge dfa2219 into facd9b0

python-pillow · Oct 15, 2019 · cee4567 · cee4567
2 parents facd9b0 + dfa2219
commit cee4567
Showing 1 changed file with 5 additions and 5 deletions.
diff --git a/src/libImaging/BcnDecode.c b/src/libImaging/BcnDecode.c
@@ -69,7 +69,7 @@ static rgba decode_565(UINT16 x) {
 	return c;
 }
 
-static void decode_bc1_color(rgba *dst, const UINT8 *src) {
+static void decode_bc1_color(rgba *dst, const UINT8 *src, int separate_alpha) {
 	bc1_color col;
 	rgba p[4];
 	int n, cw;
@@ -84,7 +84,7 @@ static void decode_bc1_color(rgba *dst, const UINT8 *src) {
 	r1 = p[1].r;
 	g1 = p[1].g;
 	b1 = p[1].b;
-	if (col.c0 > col.c1) {
+	if (col.c0 > col.c1 || separate_alpha) {
 		p[2].r = (2*r0 + 1*r1) / 3;
 		p[2].g = (2*g0 + 1*g1) / 3;
 		p[2].b = (2*b0 + 1*b1) / 3;
@@ -148,12 +148,12 @@ static void decode_bc3_alpha(char *dst, const UINT8 *src, int stride, int o) {
 }
 
 static void decode_bc1_block(rgba *col, const UINT8* src) {
-	decode_bc1_color(col, src);
+	decode_bc1_color(col, src, 0);
 }
 
 static void decode_bc2_block(rgba *col, const UINT8* src) {
 	int n, bitI, byI, av;
-	decode_bc1_color(col, src + 8);
+	decode_bc1_color(col, src + 8, 1);
 	for (n = 0; n < 16; n++) {
 		bitI = n * 4;
 		byI = bitI >> 3;
@@ -164,7 +164,7 @@ static void decode_bc2_block(rgba *col, const UINT8* src) {
 }
 
 static void decode_bc3_block(rgba *col, const UINT8* src) {
-	decode_bc1_color(col, src + 8);
+	decode_bc1_color(col, src + 8, 1);
 	decode_bc3_alpha((char *)col, src, sizeof(col[0]), 3);
 }