diff --git a/src/blitter/32bpp_sse2.cpp b/src/blitter/32bpp_sse2.cpp
--- a/src/blitter/32bpp_sse2.cpp
+++ b/src/blitter/32bpp_sse2.cpp
@@ -144,21 +144,11 @@ bmcr_alpha_blend_single:
 				break;
 			}
 			case BM_TRANSPARENT: {
-				/* Make the current colour a bit more black, so it looks like this image is transparent.
-				 * rgb = rgb * ((256/4) * 4 - (alpha/4)) / ((256/4) * 4)
-				 */
+				/* Make the current colour a bit more black, so it looks like this image is transparent. */
 				for (uint x = (uint) bp->width / 2; x > 0; x--) {
 					__m128i srcABCD = _mm_loadl_epi64((const __m128i*) src);
 					__m128i dstABCD = _mm_loadl_epi64((__m128i*) dst);
-					__m128i srcAB = _mm_unpacklo_epi8(srcABCD, _mm_setzero_si128());
-					__m128i dstAB = _mm_unpacklo_epi8(dstABCD, _mm_setzero_si128());
-					__m128i alphaAB = _mm_shufflelo_epi16(srcAB, 0x3F);
-					alphaAB = _mm_shufflehi_epi16(alphaAB, 0x3F);
-					alphaAB = _mm_srli_epi16(alphaAB, 2); // Reduce to 64 levels of shades so the max value fits in 16 bits.
-					__m128i nom = _mm_sub_epi16(tr_nom_base, alphaAB);
-					dstAB = _mm_mullo_epi16(dstAB, nom);
-					dstAB = _mm_srli_epi16(dstAB, 8);
-					dstAB = _mm_packus_epi16(dstAB, dstAB);
+					DARKEN_2();
 					_mm_storel_epi64((__m128i *) dst, dstAB);
 					src += 2;
 					dst += 2;
@@ -166,15 +156,7 @@ bmcr_alpha_blend_single:
 				if (bp->width & 1) {
 					__m128i srcABCD = _mm_cvtsi32_si128(src->data);
 					__m128i dstABCD = _mm_cvtsi32_si128(dst->data);
-					__m128i srcAB = _mm_unpacklo_epi8(srcABCD, _mm_setzero_si128());
-					__m128i dstAB = _mm_unpacklo_epi8(dstABCD, _mm_setzero_si128());
-					__m128i alphaAB = _mm_shufflelo_epi16(srcAB, 0x3F);
-					alphaAB = _mm_shufflehi_epi16(alphaAB, 0x3F);
-					alphaAB = _mm_srli_epi16(alphaAB, 2);
-					__m128i nom = _mm_sub_epi16(tr_nom_base, alphaAB);
-					dstAB = _mm_mullo_epi16(dstAB, nom);
-					dstAB = _mm_srli_epi16(dstAB, 8);
-					dstAB = _mm_packus_epi16(dstAB, dstAB);
+					DARKEN_2();
 					dst->data = _mm_cvtsi128_si32(dstAB);
 				}
 				break;