diff --git a/coders/ps.c b/coders/ps.c
index e0477e355c..40b962f1d9 100644
--- a/coders/ps.c
+++ b/coders/ps.c
@@ -1147,7 +1147,7 @@ static void inline FilenameToTitle(const char *filename,char *title,
   /*
     If parentheses remain unbalanced, close them.
   */
-  while ((depth > 0) && ((offset+1) < extent)) {
+  while ((depth > 0) && ((offset+1) < (ssize_t) extent)) {
     title[offset++]=')';
     depth--;
   }
diff --git a/coders/ps2.c b/coders/ps2.c
index af412358ff..beb8b2ef5a 100644
--- a/coders/ps2.c
+++ b/coders/ps2.c
@@ -286,7 +286,7 @@ static void inline FilenameToTitle(const char *filename,char *title,
   /*
     If parentheses remain unbalanced, close them.
   */
-  while ((depth > 0) && ((offset+1) < extent)) {
+  while ((depth > 0) && ((offset+1) < (ssize_t) extent)) {
     title[offset++]=')';
     depth--;
   }
diff --git a/coders/ps3.c b/coders/ps3.c
index bbb5fea339..dd3dd1ae89 100644
--- a/coders/ps3.c
+++ b/coders/ps3.c
@@ -264,7 +264,7 @@ static void inline FilenameToTitle(const char *filename,char *title,
   /*
     If parentheses remain unbalanced, close them.
   */
-  while ((depth > 0) && ((offset+1) < extent)) {
+  while ((depth > 0) && ((offset+1) < (ssize_t) extent)) {
     title[offset++]=')';
     depth--;
   }