fix(jpeg) robust and minimal JPEG EXIF parser

CHANGELOG.md

@@ -11,6 +11,8 @@
 - Preserve existing PageMode instead of overwriting when adding outlines
 - Add userUnit option for custom page units (PDF 1.6)
 - Support outlines that jump to specific page positions with custom zoom level
+- Add robust handling of null byte padding in JPEG images
+- Replace outdated jpeg-exif with minimal implementation
 
 ### [v0.17.2] - 2025-08-30
 

lib/image/jpeg.js

@@ -1,4 +1,79 @@
-import exif from 'jpeg-exif';
+/**
+ * Parse EXIF orientation from JPEG buffer
+ * @param {Buffer} data - JPEG image data
+ * @returns {number|null} Orientation value (1-8) or null if not found
+ */
+const parseExifOrientation = (data) => {
+  if (!data || data.length < 20) return null;
+
+  let pos = 2; // Skip SOI marker
+
+  while (pos < data.length - 4) {
+    // Skip padding bytes (some JPEG files have null bytes between segments)
+    while (pos < data.length && data[pos] !== 0xff) pos++;
+    if (pos >= data.length - 4) return null;
+
+    const marker = data.readUInt16BE(pos);
+    pos += 2;
+
+    // SOS marker - image data starts, stop searching
+    if (marker === 0xffda) return null;
+
+    // Skip standalone markers
+    if ((marker >= 0xffd0 && marker <= 0xffd9) || marker === 0xff01) continue;
+
+    if (pos + 2 > data.length) return null;
+    const segmentLength = data.readUInt16BE(pos);
+
+    // APP1 (EXIF) marker
+    if (marker === 0xffe1 && pos + 8 <= data.length) {
+      const exifHeader = data.subarray(pos + 2, pos + 8).toString('binary');
+      if (exifHeader === 'Exif\x00\x00') {
+        const tiffStart = pos + 8;
+        if (tiffStart + 8 > data.length) return null;
+
+        // Byte order
+        const byteOrder = data
+          .subarray(tiffStart, tiffStart + 2)
+          .toString('ascii');
+        const isLittleEndian = byteOrder === 'II';
+        if (!isLittleEndian && byteOrder !== 'MM') return null;
+
+        const read16 = isLittleEndian
+          ? (o) => data.readUInt16LE(o)
+          : (o) => data.readUInt16BE(o);
+        const read32 = isLittleEndian
+          ? (o) => data.readUInt32LE(o)
+          : (o) => data.readUInt32BE(o);
+
+        // Verify TIFF magic number (42)
+        if (read16(tiffStart + 2) !== 42) return null;
+
+        // IFD0 offset
+        const ifdPos = tiffStart + read32(tiffStart + 4);
+        if (ifdPos + 2 > data.length) return null;
+
+        const entryCount = read16(ifdPos);
+
+        // Scan IFD entries for Orientation tag (0x0112)
+        for (let i = 0; i < entryCount; i++) {
+          const entryPos = ifdPos + 2 + i * 12;
+          if (entryPos + 12 > data.length) return null;
+
+          if (read16(entryPos) === 0x0112) {
+            const value = read16(entryPos + 8);
+            return value >= 1 && value <= 8 ? value : null;
+          }
+        }
+        return null;
+      }
+    }
+
+    pos += segmentLength;
+  }
+
+  return null;
+};
 
 const MARKERS = [
   0xffc0, 0xffc1, 0xffc2, 0xffc3, 0xffc5, 0xffc6, 0xffc7, 0xffc8, 0xffc9,
@@ -21,10 +96,14 @@ class JPEG {
     }
 
     // Parse the EXIF orientation
-    this.orientation = exif.fromBuffer(this.data).Orientation || 1;
+    this.orientation = parseExifOrientation(this.data) || 1;
 
     let pos = 2;
     while (pos < this.data.length) {
+      // Skip padding bytes (some JPEG files have null bytes between segments)
+      while (pos < this.data.length && this.data[pos] !== 0xff) pos++;
+      if (pos >= this.data.length) break;
+
       marker = this.data.readUInt16BE(pos);
       pos += 2;
       if (MARKERS.includes(marker)) {

package.json

@@ -50,7 +50,6 @@
   "dependencies": {
     "crypto-js": "^4.2.0",
     "fontkit": "^2.0.4",
-    "jpeg-exif": "^1.1.4",
     "linebreak": "^1.1.0",
     "png-js": "^1.0.0"
   },

rollup.config.js

@@ -11,8 +11,7 @@ const external = [
   'linebreak',
   'png-js',
   'crypto-js',
-  'saslprep',
-  'jpeg-exif'
+  'saslprep'
 ];
 
 const supportedBrowsers = [

tests/unit/image.spec.js

@@ -1,4 +1,6 @@
 import PDFDocument from '../../lib/document';
+import fs from 'fs';
+import JPEG from '../../lib/image/jpeg';
 
 describe('Image', function () {
   /**
@@ -18,4 +20,12 @@ describe('Image', function () {
     document.image('./tests/images/bee.png');
     expect(document.y).toBe(originalY + imageHeight);
   });
+
+  test('parse JPEG with null byte padding in EXIF (issue #1175)', () => {
+    const data = fs.readFileSync('./tests/images/issue-1175.jpeg');
+    const jpeg = new JPEG(data, 'test');
+    expect(jpeg.width).toBe(375);
+    expect(jpeg.height).toBe(500);
+    expect(jpeg.orientation).toBe(1);
+  });
 });

yarn.lock

@@ -5324,13 +5324,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"jpeg-exif@npm:^1.1.4":
-  version: 1.1.4
-  resolution: "jpeg-exif@npm:1.1.4"
-  checksum: 10c0/0f9225b2423184d60c66b3d7361176801c17ede92fc9b3c044fcf00f379a5a1d424b360ecf0027dda47d405d253c7b62bf5b353fb08b2589e3650f38cc575e82
-  languageName: node
-  linkType: hard
-
 "js-stringify@npm:^1.0.2":
   version: 1.0.2
   resolution: "js-stringify@npm:1.0.2"
@@ -6325,7 +6318,6 @@ __metadata:
     globals: "npm:^15.14.0"
     jest: "npm:^29.7.0"
     jest-image-snapshot: "npm:^6.4.0"
-    jpeg-exif: "npm:^1.1.4"
     linebreak: "npm:^1.1.0"
     markdown: "npm:~0.5.0"
     pdfjs-dist: "npm:^2.14.305"