diff --git a/java/TJBench.java b/java/TJBench.java
index 617d312d..c9d110c3 100644
--- a/java/TJBench.java
+++ b/java/TJBench.java
@@ -236,7 +236,7 @@ class TJBench {
                            "_" + sizeStr + ".bmp");
 
     saveImage(tempStr, dstBuf, scaledw, scaledh, pf);
-    int ndx = tempStr.indexOf('.');
+    int ndx = tempStr.lastIndexOf('.');
     tempStr = new String(tempStr.substring(0, ndx) + "-err.bmp");
     if (srcBuf != null && sf.getNum() == 1 && sf.getDenom() == 1) {
       if (quiet == 0)
@@ -432,7 +432,7 @@ class TJBench {
     fis.read(srcBuf, 0, srcSize);
     fis.close();
 
-    int index = fileName.indexOf('.');
+    int index = fileName.lastIndexOf('.');
     if (index >= 0)
       fileName = new String(fileName.substring(0, index));
 
@@ -846,7 +846,7 @@ class TJBench {
         srcBuf = loadImage(argv[0], width, height, pf);
         w = width[0];  h = height[0];
         int index = -1;
-        if ((index = argv[0].indexOf('.')) >= 0)
+        if ((index = argv[0].lastIndexOf('.')) >= 0)
           argv[0] = argv[0].substring(0, index);
       }
 
diff --git a/tjbenchtest.in b/tjbenchtest.in
index 5e08c9b3..4c4e0406 100755
--- a/tjbenchtest.in
+++ b/tjbenchtest.in
@@ -22,7 +22,7 @@ runme()
 EXT=bmp
 IMAGES="vgl_5674_0098.${EXT} vgl_6434_0018a.${EXT} vgl_6548_0026a.${EXT} nightshot_iso_100.${EXT}"
 IMGDIR=@srcdir@/testimages
-OUTDIR=__tjbenchtest_output
+OUTDIR=`mktemp -d /tmp/__tjbenchtest_output.XXXXXX`
 EXEDIR=.
 BMPARG=
 NSARG=
diff --git a/tjbenchtest.java.in b/tjbenchtest.java.in
index 20546035..acdabd08 100755
--- a/tjbenchtest.java.in
+++ b/tjbenchtest.java.in
@@ -21,7 +21,7 @@ runme()
 
 IMAGES="vgl_5674_0098.bmp vgl_6434_0018a.bmp vgl_6548_0026a.bmp nightshot_iso_100.bmp"
 IMGDIR=@srcdir@/testimages
-OUTDIR=__tjbenchtest_java_output
+OUTDIR=`mktemp -d /tmp/__tjbenchtest_java_output.XXXXXX`
 EXEDIR=.
 JAVA="@JAVA@ -cp java/turbojpeg.jar -Djava.library.path=.libs"
 BMPARG=