diff --git a/src/core/colorspace.js b/src/core/colorspace.js
index 287b6cb0b..e06019043 100644
--- a/src/core/colorspace.js
+++ b/src/core/colorspace.js
@@ -379,24 +379,46 @@ class AlternateCS extends ColorSpace {
       : new Uint8ClampedArray(baseNumComps * count);
     const numComps = this.numComps;
 
+    const tintCache = new Map();
+    // Use an integer cache-key when possible, since that's a lot faster than
+    // string concatenation.
+    const int32Key =
+      numComps <= 4 &&
+      (src instanceof Uint8Array || src instanceof Uint8ClampedArray);
+
     const scaled = new Float32Array(numComps);
     const tinted = new Float32Array(baseNumComps);
-    let i, j;
+    let i, j, key, val;
 
     for (i = 0; i < count; i++) {
+      key = int32Key ? 0 : "";
+
       for (j = 0; j < numComps; j++) {
-        scaled[j] = src[srcOffset++] * scale;
+        val = src[srcOffset++];
+        scaled[j] = val * scale;
+
+        key += int32Key ? val << (8 * j) : val + "_";
       }
-      tintFn(scaled, 0, tinted, 0);
-      if (usesZeroToOneRange) {
-        for (j = 0; j < baseNumComps; j++) {
-          baseBuf[pos++] = tinted[j] * 255;
-        }
-      } else {
-        base.getRgbItem(tinted, 0, baseBuf, pos);
+
+      const cached = tintCache.get(key);
+      if (cached) {
+        baseBuf.set(cached, pos);
         pos += baseNumComps;
+      } else {
+        tintFn(scaled, 0, tinted, 0);
+
+        if (usesZeroToOneRange) {
+          for (j = 0; j < baseNumComps; j++) {
+            baseBuf[pos++] = tinted[j] * 255;
+          }
+        } else {
+          base.getRgbItem(tinted, 0, baseBuf, pos);
+          pos += baseNumComps;
+        }
+        tintCache.set(key, baseBuf.slice(pos - baseNumComps, pos));
       }
     }
+    tintCache.clear();
 
     if (!isPassthrough) {
       base.getRgbBuffer(baseBuf, 0, count, dest, destOffset, 8, alpha01);
diff --git a/src/core/function.js b/src/core/function.js
index f426f15bf..702e36b3e 100644
--- a/src/core/function.js
+++ b/src/core/function.js
@@ -392,12 +392,11 @@ class PDFFunction {
     // seen in our tests.
     const MAX_CACHE_SIZE = 2048 * 4;
     let cache_available = MAX_CACHE_SIZE;
-    const tmpBuf = new Float32Array(numInputs);
+    const input = new Float32Array(numInputs);
 
     return function constructPostScriptFn(src, srcOffset, dest, destOffset) {
       let i, value;
       let key = "";
-      const input = tmpBuf;
       for (i = 0; i < numInputs; i++) {
         value = src[srcOffset + i];
         input[i] = value;
diff --git a/test/pdfs/pr5134.pdf.link b/test/pdfs/pr5134.pdf.link
new file mode 100644
index 000000000..721dc2fdc
--- /dev/null
+++ b/test/pdfs/pr5134.pdf.link
@@ -0,0 +1 @@
+https://web.archive.org/web/20140211020222/http://www.coachusa.com/CoachUsaAssets/files/97/route45.pdf
diff --git a/test/test_manifest.json b/test/test_manifest.json
index bfa914535..394c60a6a 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -2254,6 +2254,15 @@
     "lastPage": 1,
     "type": "eq"
   },
+  {
+    "id": "pr5134",
+    "file": "pdfs/pr5134.pdf",
+    "md5": "6a701a163472e071a2519348b55cbac1",
+    "rounds": 1,
+    "link": true,
+    "firstPage": 2,
+    "type": "eq"
+  },
   {
     "id": "issue5599",
     "file": "pdfs/issue5599.pdf",