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Common/Data/Format/PNGLoad.h

@@ -15,6 +15,8 @@ int pngLoadPtr(const unsigned  char *input_ptr, size_t input_len, int *pwidth,
 // PNG peeker - just read the start of a PNG straight into this struct, in order to
 // look at basic parameters like width and height. Note that while PNG is a chunk-based
 // format, the IHDR chunk is REQUIRED to be the first one, so this will work.
+// Does not handle Apple's weirdo extension CgBI. http://iphonedevwiki.net/index.php/CgBI_file_format
+// That should not be an issue.
 struct PNGHeaderPeek {
 	uint32_t magic;
 	uint32_t ignore0;

Core/TextureReplacer.cpp

@@ -648,12 +648,13 @@ bool TextureReplacer::PopulateLevelFromZip(ReplacedTextureLevel &level, bool ign
 	} else if (imageType == ReplacedImageType::PNG) {
 		PNGHeaderPeek headerPeek;
 		good = zip_fread(zf, &headerPeek, sizeof(headerPeek)) == sizeof(headerPeek);
-		if (headerPeek.IsValidPNGHeader()) {
+		if (good && headerPeek.IsValidPNGHeader()) {
 			level.w = headerPeek.Width();
 			level.h = headerPeek.Height();
 			good = true;
 		} else {
 			ERROR_LOG(G3D, "Could not get PNG dimensions: %s (zip)", level.file.ToVisualString().c_str());
+			good = false;
 		}
 	} else {
 		ERROR_LOG(G3D, "Could not load texture replacement info: %s - unsupported format (zip)", level.file.ToVisualString().c_str());