REPORT-103847 优化补充内容

fine-itext-old/src/main/java/com/fr/third/com/lowagie/text/Image.java

@@ -753,10 +753,6 @@ public abstract class Image extends Rectangle {
 						} else if (transparency == null) {
 							if (alpha == 0) {
 								transparentPixel = pixels[j] & 0xffffff;
-								transparency = new int[6];
-								transparency[0] = transparency[1] = (transparentPixel >> 16) & 0xff;
-								transparency[2] = transparency[3] = (transparentPixel >> 8) & 0xff;
-								transparency[4] = transparency[5] = transparentPixel & 0xff;
 								// Added by Michael Klink
 								// Check whether this value for transparent pixels
 								// has already been used for a non-transparent one
@@ -768,10 +764,15 @@ public abstract class Image extends Rectangle {
 										// for transparency; we could still use an image
 										// mask but for simplicity let's use a soft mask
 										// which already is implemented here
+										// stackOverFlow：https://stackoverflow.com/questions/39119776/itext-binary-transparency-bug
 										shades = true;
 										break;
 									}
 								}
+								transparency = new int[6];
+								transparency[0] = transparency[1] = (transparentPixel >> 16) & 0xff;
+								transparency[2] = transparency[3] = (transparentPixel >> 8) & 0xff;
+								transparency[4] = transparency[5] = transparentPixel & 0xff;
 							}
 						} else if (((pixels[j] & 0xffffff) != transparentPixel) && (alpha == 0)) {
 							shades = true;