Fix for bug #45030

ext/gd/libgd/gd.c

@@ -2613,6 +2613,7 @@ void gdImageCopyResampled (gdImagePtr dst, gdImagePtr src, int dstX, int dstY, i
 				green /= spixels;
 				blue /= spixels;
 				alpha /= spixels;
+				alpha += 0.5;
 			}
 			if ( alpha_sum != 0.0f) {
 				if( contrib_sum != 0.0f) {

ext/gd/libgd/gd_png.c

@@ -689,7 +689,12 @@ void gdImagePngCtxEx (gdImagePtr im, gdIOCtx * outfile, int level, int basefilte
 					 */
 					a = gdTrueColorGetAlpha(thisPixel);
 					/* Andrew Hull: >> 6, not >> 7! (gd 2.0.5) */
-					*pOutputRow++ = 255 - ((a << 1) + (a >> 6));
+					if (a == 127) {
+						*pOutputRow++ = 0;
+					} else {
+						*pOutputRow++ = 255 - ((a << 1) + (a >> 6));
+					}
+
 				}
 			}
 		}