From 8304df2520ad414b013ae7e98444b3808156b8ff Mon Sep 17 00:00:00 2001
From: Calixte Denizet <calixte.denizet@gmail.com>
Date: Mon, 6 Mar 2023 10:57:05 +0100
Subject: [PATCH] Apply transfer filters to any graphic commands

---
 src/display/canvas.js         | 29 +++++++++++++++++++++++------
 src/display/display_utils.js  |  2 +-
 test/pdfs/issue16114.pdf.link |  2 ++
 test/test_manifest.json       |  8 ++++++++
 4 files changed, 34 insertions(+), 7 deletions(-)
 create mode 100644 test/pdfs/issue16114.pdf.link

diff --git a/src/display/canvas.js b/src/display/canvas.js
index 74da9d151..5863b7528 100644
--- a/src/display/canvas.js
+++ b/src/display/canvas.js
@@ -38,6 +38,7 @@ import {
   TilingPattern,
 } from "./pattern_helper.js";
 import { convertBlackAndWhiteToRGBA } from "../shared/image_utils.js";
+import { isNodeJS } from "../shared/is_node.js";
 
 // <canvas> contexts store most of the state we need natively.
 // However, PDF needs a bit more state, which we store here.
@@ -837,6 +838,7 @@ function copyCtxState(sourceCtx, destCtx) {
     "miterLimit",
     "globalCompositeOperation",
     "font",
+    "filter",
   ];
   for (const property of properties) {
     if (sourceCtx[property] !== undefined) {
@@ -863,6 +865,9 @@ function resetCtxToDefault(ctx, foregroundColor) {
     ctx.setLineDash([]);
     ctx.lineDashOffset = 0;
   }
+  if (!isNodeJS) {
+    ctx.filter = "none";
+  }
 }
 
 function composeSMaskBackdrop(bytes, r0, g0, b0) {
@@ -1576,9 +1581,12 @@ class CanvasGraphics {
           this.checkSMaskState();
           break;
         case "TR":
-          this.current.transferMaps = this.filterFactory
-            ? this.filterFactory.addFilter(value)
-            : value;
+          if (this.filterFactory) {
+            this.ctx.filter = this.current.transferMaps =
+              this.filterFactory.addFilter(value);
+          } else {
+            this.current.transferMaps = value;
+          }
           break;
       }
     }
@@ -3025,7 +3033,7 @@ class CanvasGraphics {
   }
 
   applyTransferMapsToBitmap(imgData) {
-    if (!this.current.transferMaps) {
+    if (!this.current.transferMaps || this.current.transferMaps === "none") {
       return imgData.bitmap;
     }
     const { bitmap, width, height } = imgData;
@@ -3037,7 +3045,7 @@ class CanvasGraphics {
     const tmpCtx = tmpCanvas.context;
     tmpCtx.filter = this.current.transferMaps;
     tmpCtx.drawImage(bitmap, 0, 0);
-    tmpCtx.filter = "";
+    tmpCtx.filter = "none";
 
     return tmpCanvas.canvas;
   }
@@ -3051,6 +3059,15 @@ class CanvasGraphics {
     const ctx = this.ctx;
 
     this.save();
+
+    if (!isNodeJS) {
+      // The filter, if any, will be applied in applyTransferMapsToBitmap.
+      // It must be applied to the image before rescaling else some artifacts
+      // could appear.
+      // The final restore will reset it to its value.
+      ctx.filter = "none";
+    }
+
     // scale the image to the unit square
     ctx.scale(1 / width, -1 / height);
 
@@ -3106,7 +3123,7 @@ class CanvasGraphics {
     const ctx = this.ctx;
     let imgToPaint;
     if (imgData.bitmap) {
-      imgToPaint = this.applyTransferMapsToBitmap(imgData);
+      imgToPaint = imgData.bitmap;
     } else {
       const w = imgData.width;
       const h = imgData.height;
diff --git a/src/display/display_utils.js b/src/display/display_utils.js
index 1e33b34d1..1e5ab9f6e 100644
--- a/src/display/display_utils.js
+++ b/src/display/display_utils.js
@@ -81,7 +81,7 @@ class FilterFactory {
 
   addFilter(maps) {
     if (!maps) {
-      return "";
+      return "none";
     }
 
     // When a page is zoomed the page is re-drawn but the maps are likely
diff --git a/test/pdfs/issue16114.pdf.link b/test/pdfs/issue16114.pdf.link
new file mode 100644
index 000000000..45692bdd8
--- /dev/null
+++ b/test/pdfs/issue16114.pdf.link
@@ -0,0 +1,2 @@
+https://github.com/mozilla/pdf.js/files/10896497/spider.pdf
+
diff --git a/test/test_manifest.json b/test/test_manifest.json
index cb23055be..d91dfc659 100644
--- a/test/test_manifest.json
+++ b/test/test_manifest.json
@@ -7437,5 +7437,13 @@
       "md5": "76d680172c969c77c9fb650b3d822ad6",
       "link": true,
       "type": "other"
+   },
+   {
+      "id": "issue16114",
+      "file": "pdfs/issue16114.pdf",
+      "md5": "c04827ea33692e0f94a5e51716d9aa2e",
+      "rounds": 1,
+      "link": true,
+      "type": "eq"
    }
 ]