When decompressing to a 4-byte RGB buffer, set the unused byte to 0xFF so it can be interpreted as an opaque alpha channel.

git-svn-id: svn://svn.code.sf.net/p/libjpeg-turbo/code/trunk@699 632fc199-4ca6-4c93-a231-07263d6284db

1 files changed, 6 insertions, 1 deletions

diff --git a/tjunittest.c b/tjunittest.c
index 08d8fe2..3a57347 100644
--- a/tjunittest.c
+++ b/tjunittest.c
@@ -68,6 +68,8 @@ const char *pixFormatStr[TJ_NUMPF]=
 	"RGB", "BGR", "RGBX", "BGRX", "XBGR", "XRGB", "Grayscale"
 };
 
+const int alphaOffset[TJ_NUMPF] = {-1, -1, 3, 3, 0, 0, -1};
+
 const int _3byteFormats[]={TJPF_RGB, TJPF_BGR};
 const int _4byteFormats[]={TJPF_RGBX, TJPF_BGRX, TJPF_XBGR, TJPF_XRGB};
 const int _onlyGray[]={TJPF_GRAY};
@@ -156,6 +158,7 @@ int checkBuf(unsigned char *buf, int w, int h, int pf, int subsamp,
 	int roffset=tjRedOffset[pf];
 	int goffset=tjGreenOffset[pf];
 	int boffset=tjBlueOffset[pf];
+	int aoffset=alphaOffset[pf];
 	int ps=tjPixelSize[pf];
 	int index, row, col, retval=1;
 	int halfway=16*sf.num/sf.denom;
@@ -165,12 +168,13 @@ int checkBuf(unsigned char *buf, int w, int h, int pf, int subsamp,
 	{
 		for(col=0; col<w; col++)
 		{
-			unsigned char r, g, b;
+			unsigned char r, g, b, a;
 			if(flags&TJFLAG_BOTTOMUP) index=(h-row-1)*w+col;
 			else index=row*w+col;
 			r=buf[index*ps+roffset];
 			g=buf[index*ps+goffset];
 			b=buf[index*ps+boffset];
+			a=aoffset>=0? buf[index*ps+aoffset]:0xFF;
 			if(((row/blocksize)+(col/blocksize))%2==0)
 			{
 				if(row<halfway)
@@ -207,6 +211,7 @@ int checkBuf(unsigned char *buf, int w, int h, int pf, int subsamp,
 					}
 				}
 			}
+			checkval255(a);
 		}
 	}