diff --git a/src/core/evaluator.js b/src/core/evaluator.js
index 1200cba9f..6e47bda46 100644
--- a/src/core/evaluator.js
+++ b/src/core/evaluator.js
@@ -20,7 +20,7 @@ import {
   UNSUPPORTED_FEATURES, Util, warn
 } from '../shared/util';
 import { CMapFactory, IdentityCMap } from './cmap';
-import { DecodeStream, JpegStream, Stream } from './stream';
+import { DecodeStream, Stream } from './stream';
 import {
   Dict, isCmd, isDict, isEOF, isName, isRef, isStream, Name
 } from './primitives';
@@ -44,6 +44,7 @@ import { ColorSpace } from './colorspace';
 import { getGlyphsUnicode } from './glyphlist';
 import { getMetrics } from './metrics';
 import { isPDFFunction } from './function';
+import { JpegStream } from './jpeg_stream';
 import { MurmurHash3_64 } from './murmurhash3';
 import { OperatorList } from './operator_list';
 import { PDFImage } from './image';
diff --git a/src/core/image.js b/src/core/image.js
index 9010bf970..cfc6555c8 100644
--- a/src/core/image.js
+++ b/src/core/image.js
@@ -14,9 +14,10 @@
  */
 
 import { assert, FormatError, ImageKind, info, warn } from '../shared/util';
-import { DecodeStream, JpegStream } from './stream';
 import { isStream, Name } from './primitives';
 import { ColorSpace } from './colorspace';
+import { DecodeStream } from './stream';
+import { JpegStream } from './jpeg_stream';
 import { JpxImage } from './jpx';
 
 var PDFImage = (function PDFImageClosure() {
diff --git a/src/core/jbig2_stream.js b/src/core/jbig2_stream.js
index ed7bec65a..1e3736b6a 100644
--- a/src/core/jbig2_stream.js
+++ b/src/core/jbig2_stream.js
@@ -22,7 +22,7 @@ import { shadow } from '../shared/util';
  * For JBIG2's we use a library to decode these images and
  * the stream behaves like all the other DecodeStreams.
  */
-var Jbig2Stream = (function Jbig2StreamClosure() {
+let Jbig2Stream = (function Jbig2StreamClosure() {
   function Jbig2Stream(stream, maybeLength, dict, params) {
     this.stream = stream;
     this.maybeLength = maybeLength;
@@ -36,36 +36,39 @@ var Jbig2Stream = (function Jbig2StreamClosure() {
 
   Object.defineProperty(Jbig2Stream.prototype, 'bytes', {
     get() {
-      // If this.maybeLength is null, we'll get the entire stream.
+      // If `this.maybeLength` is null, we'll get the entire stream.
       return shadow(this, 'bytes', this.stream.getBytes(this.maybeLength));
     },
     configurable: true,
   });
 
-  Jbig2Stream.prototype.ensureBuffer = function(req) {
-    if (this.bufferLength) {
+  Jbig2Stream.prototype.ensureBuffer = function(requested) {
+    // No-op, since `this.readBlock` will always parse the entire image and
+    // directly insert all of its data into `this.buffer`.
+  };
+
+  Jbig2Stream.prototype.readBlock = function() {
+    if (this.eof) {
       return;
     }
+    let jbig2Image = new Jbig2Image();
 
-    var jbig2Image = new Jbig2Image();
-
-    var chunks = [];
+    let chunks = [];
     if (isDict(this.params)) {
-      var globalsStream = this.params.get('JBIG2Globals');
+      let globalsStream = this.params.get('JBIG2Globals');
       if (isStream(globalsStream)) {
-        var globals = globalsStream.getBytes();
+        let globals = globalsStream.getBytes();
         chunks.push({ data: globals, start: 0, end: globals.length, });
       }
     }
     chunks.push({ data: this.bytes, start: 0, end: this.bytes.length, });
-    var data = jbig2Image.parseChunks(chunks);
-    var dataLength = data.length;
+    let data = jbig2Image.parseChunks(chunks);
+    let dataLength = data.length;
 
     // JBIG2 had black as 1 and white as 0, inverting the colors
-    for (var i = 0; i < dataLength; i++) {
+    for (let i = 0; i < dataLength; i++) {
       data[i] ^= 0xFF;
     }
-
     this.buffer = data;
     this.bufferLength = dataLength;
     this.eof = true;
diff --git a/src/core/jpeg_stream.js b/src/core/jpeg_stream.js
new file mode 100644
index 000000000..75936ab8f
--- /dev/null
+++ b/src/core/jpeg_stream.js
@@ -0,0 +1,117 @@
+/* Copyright 2012 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { createObjectURL, shadow } from '../shared/util';
+import { DecodeStream } from './stream';
+import { isDict } from './primitives';
+import { JpegImage } from './jpg';
+
+/**
+ * Depending on the type of JPEG a JpegStream is handled in different ways. For
+ * JPEG's that are supported natively such as DeviceGray and DeviceRGB the image
+ * data is stored and then loaded by the browser. For unsupported JPEG's we use
+ * a library to decode these images and the stream behaves like all the other
+ * DecodeStreams.
+ */
+let JpegStream = (function JpegStreamClosure() {
+  function JpegStream(stream, maybeLength, dict, params) {
+    // Some images may contain 'junk' before the SOI (start-of-image) marker.
+    // Note: this seems to mainly affect inline images.
+    let ch;
+    while ((ch = stream.getByte()) !== -1) {
+      if (ch === 0xFF) { // Find the first byte of the SOI marker (0xFFD8).
+        stream.skip(-1); // Reset the stream position to the SOI.
+        break;
+      }
+    }
+    this.stream = stream;
+    this.maybeLength = maybeLength;
+    this.dict = dict;
+    this.params = params;
+
+    DecodeStream.call(this, maybeLength);
+  }
+
+  JpegStream.prototype = Object.create(DecodeStream.prototype);
+
+  Object.defineProperty(JpegStream.prototype, 'bytes', {
+    get: function JpegStream_bytes() {
+      // If `this.maybeLength` is null, we'll get the entire stream.
+      return shadow(this, 'bytes', this.stream.getBytes(this.maybeLength));
+    },
+    configurable: true,
+  });
+
+  JpegStream.prototype.ensureBuffer = function(requested) {
+    // No-op, since `this.readBlock` will always parse the entire image and
+    // directly insert all of its data into `this.buffer`.
+  };
+
+  JpegStream.prototype.readBlock = function() {
+    if (this.eof) {
+      return;
+    }
+    let jpegImage = new JpegImage();
+
+    // Checking if values need to be transformed before conversion.
+    let decodeArr = this.dict.getArray('Decode', 'D');
+    if (this.forceRGB && Array.isArray(decodeArr)) {
+      let bitsPerComponent = this.dict.get('BitsPerComponent') || 8;
+      let decodeArrLength = decodeArr.length;
+      let transform = new Int32Array(decodeArrLength);
+      let transformNeeded = false;
+      let maxValue = (1 << bitsPerComponent) - 1;
+      for (let i = 0; i < decodeArrLength; i += 2) {
+        transform[i] = ((decodeArr[i + 1] - decodeArr[i]) * 256) | 0;
+        transform[i + 1] = (decodeArr[i] * maxValue) | 0;
+        if (transform[i] !== 256 || transform[i + 1] !== 0) {
+          transformNeeded = true;
+        }
+      }
+      if (transformNeeded) {
+        jpegImage.decodeTransform = transform;
+      }
+    }
+    // Fetching the 'ColorTransform' entry, if it exists.
+    if (isDict(this.params)) {
+      let colorTransform = this.params.get('ColorTransform');
+      if (Number.isInteger(colorTransform)) {
+        jpegImage.colorTransform = colorTransform;
+      }
+    }
+
+    jpegImage.parse(this.bytes);
+    let data = jpegImage.getData(this.drawWidth, this.drawHeight,
+                                 this.forceRGB);
+    this.buffer = data;
+    this.bufferLength = data.length;
+    this.eof = true;
+  };
+
+  JpegStream.prototype.getBytes = function(length) {
+    this.readBlock();
+    return this.buffer;
+  };
+
+  JpegStream.prototype.getIR = function(forceDataSchema = false) {
+    return createObjectURL(this.bytes, 'image/jpeg', forceDataSchema);
+  };
+
+  return JpegStream;
+})();
+
+export {
+  JpegStream,
+};
diff --git a/src/core/jpx_stream.js b/src/core/jpx_stream.js
new file mode 100644
index 000000000..7e564196f
--- /dev/null
+++ b/src/core/jpx_stream.js
@@ -0,0 +1,96 @@
+/* Copyright 2012 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { DecodeStream } from './stream';
+import { JpxImage } from './jpx';
+import { shadow } from '../shared/util';
+
+/**
+ * For JPEG 2000's we use a library to decode these images and
+ * the stream behaves like all the other DecodeStreams.
+ */
+let JpxStream = (function JpxStreamClosure() {
+  function JpxStream(stream, maybeLength, dict, params) {
+    this.stream = stream;
+    this.maybeLength = maybeLength;
+    this.dict = dict;
+    this.params = params;
+
+    DecodeStream.call(this, maybeLength);
+  }
+
+  JpxStream.prototype = Object.create(DecodeStream.prototype);
+
+  Object.defineProperty(JpxStream.prototype, 'bytes', {
+    get: function JpxStream_bytes() {
+      // If `this.maybeLength` is null, we'll get the entire stream.
+      return shadow(this, 'bytes', this.stream.getBytes(this.maybeLength));
+    },
+    configurable: true,
+  });
+
+  JpxStream.prototype.ensureBuffer = function(requested) {
+    // No-op, since `this.readBlock` will always parse the entire image and
+    // directly insert all of its data into `this.buffer`.
+  };
+
+  JpxStream.prototype.readBlock = function() {
+    if (this.eof) {
+      return;
+    }
+    let jpxImage = new JpxImage();
+    jpxImage.parse(this.bytes);
+
+    let width = jpxImage.width;
+    let height = jpxImage.height;
+    let componentsCount = jpxImage.componentsCount;
+    let tileCount = jpxImage.tiles.length;
+    if (tileCount === 1) {
+      this.buffer = jpxImage.tiles[0].items;
+    } else {
+      let data = new Uint8ClampedArray(width * height * componentsCount);
+
+      for (let k = 0; k < tileCount; k++) {
+        let tileComponents = jpxImage.tiles[k];
+        let tileWidth = tileComponents.width;
+        let tileHeight = tileComponents.height;
+        let tileLeft = tileComponents.left;
+        let tileTop = tileComponents.top;
+
+        let src = tileComponents.items;
+        let srcPosition = 0;
+        let dataPosition = (width * tileTop + tileLeft) * componentsCount;
+        let imgRowSize = width * componentsCount;
+        let tileRowSize = tileWidth * componentsCount;
+
+        for (let j = 0; j < tileHeight; j++) {
+          let rowBytes = src.subarray(srcPosition, srcPosition + tileRowSize);
+          data.set(rowBytes, dataPosition);
+          srcPosition += tileRowSize;
+          dataPosition += imgRowSize;
+        }
+      }
+      this.buffer = data;
+    }
+    this.bufferLength = this.buffer.length;
+    this.eof = true;
+  };
+
+  return JpxStream;
+})();
+
+export {
+  JpxStream,
+};
diff --git a/src/core/parser.js b/src/core/parser.js
index 54cfc3568..e6e60cd49 100644
--- a/src/core/parser.js
+++ b/src/core/parser.js
@@ -14,8 +14,8 @@
  */
 
 import {
-  Ascii85Stream, AsciiHexStream, FlateStream, JpegStream, JpxStream, LZWStream,
-  NullStream, PredictorStream, RunLengthStream
+  Ascii85Stream, AsciiHexStream, FlateStream, LZWStream, NullStream,
+  PredictorStream, RunLengthStream
 } from './stream';
 import {
   assert, FormatError, info, isNum, isString, MissingDataException, StreamType,
@@ -26,6 +26,8 @@ import {
 } from './primitives';
 import { CCITTFaxStream } from './ccitt_stream';
 import { Jbig2Stream } from './jbig2_stream';
+import { JpegStream } from './jpeg_stream';
+import { JpxStream } from './jpx_stream';
 
 var MAX_LENGTH_TO_CACHE = 1000;
 
diff --git a/src/core/stream.js b/src/core/stream.js
index fbf957e8a..4bc5eb57e 100644
--- a/src/core/stream.js
+++ b/src/core/stream.js
@@ -13,12 +13,8 @@
  * limitations under the License.
  */
 
-import {
-  createObjectURL, FormatError, isSpace, shadow, stringToBytes, Util
-} from '../shared/util';
+import { FormatError, isSpace, stringToBytes, Util } from '../shared/util';
 import { isDict } from './primitives';
-import { JpegImage } from './jpg';
-import { JpxImage } from './jpx';
 
 var Stream = (function StreamClosure() {
   function Stream(arrayBuffer, start, length, dict) {
@@ -871,165 +867,6 @@ var PredictorStream = (function PredictorStreamClosure() {
   return PredictorStream;
 })();
 
-/**
- * Depending on the type of JPEG a JpegStream is handled in different ways. For
- * JPEG's that are supported natively such as DeviceGray and DeviceRGB the image
- * data is stored and then loaded by the browser.  For unsupported JPEG's we use
- * a library to decode these images and the stream behaves like all the other
- * DecodeStreams.
- */
-var JpegStream = (function JpegStreamClosure() {
-  function JpegStream(stream, maybeLength, dict, params) {
-    // Some images may contain 'junk' before the SOI (start-of-image) marker.
-    // Note: this seems to mainly affect inline images.
-    var ch;
-    while ((ch = stream.getByte()) !== -1) {
-      if (ch === 0xFF) { // Find the first byte of the SOI marker (0xFFD8).
-        stream.skip(-1); // Reset the stream position to the SOI.
-        break;
-      }
-    }
-    this.stream = stream;
-    this.maybeLength = maybeLength;
-    this.dict = dict;
-    this.params = params;
-
-    DecodeStream.call(this, maybeLength);
-  }
-
-  JpegStream.prototype = Object.create(DecodeStream.prototype);
-
-  Object.defineProperty(JpegStream.prototype, 'bytes', {
-    get: function JpegStream_bytes() {
-      // If this.maybeLength is null, we'll get the entire stream.
-      return shadow(this, 'bytes', this.stream.getBytes(this.maybeLength));
-    },
-    configurable: true,
-  });
-
-  JpegStream.prototype.ensureBuffer = function JpegStream_ensureBuffer(req) {
-    if (this.bufferLength) {
-      return;
-    }
-    var jpegImage = new JpegImage();
-
-    // Checking if values need to be transformed before conversion.
-    var decodeArr = this.dict.getArray('Decode', 'D');
-    if (this.forceRGB && Array.isArray(decodeArr)) {
-      var bitsPerComponent = this.dict.get('BitsPerComponent') || 8;
-      var decodeArrLength = decodeArr.length;
-      var transform = new Int32Array(decodeArrLength);
-      var transformNeeded = false;
-      var maxValue = (1 << bitsPerComponent) - 1;
-      for (var i = 0; i < decodeArrLength; i += 2) {
-        transform[i] = ((decodeArr[i + 1] - decodeArr[i]) * 256) | 0;
-        transform[i + 1] = (decodeArr[i] * maxValue) | 0;
-        if (transform[i] !== 256 || transform[i + 1] !== 0) {
-          transformNeeded = true;
-        }
-      }
-      if (transformNeeded) {
-        jpegImage.decodeTransform = transform;
-      }
-    }
-    // Fetching the 'ColorTransform' entry, if it exists.
-    if (isDict(this.params)) {
-      var colorTransform = this.params.get('ColorTransform');
-      if (Number.isInteger(colorTransform)) {
-        jpegImage.colorTransform = colorTransform;
-      }
-    }
-
-    jpegImage.parse(this.bytes);
-    var data = jpegImage.getData(this.drawWidth, this.drawHeight,
-                                 this.forceRGB);
-    this.buffer = data;
-    this.bufferLength = data.length;
-    this.eof = true;
-  };
-
-  JpegStream.prototype.getBytes = function JpegStream_getBytes(length) {
-    this.ensureBuffer();
-    return this.buffer;
-  };
-
-  JpegStream.prototype.getIR = function JpegStream_getIR(forceDataSchema) {
-    return createObjectURL(this.bytes, 'image/jpeg', forceDataSchema);
-  };
-
-  return JpegStream;
-})();
-
-/**
- * For JPEG 2000's we use a library to decode these images and
- * the stream behaves like all the other DecodeStreams.
- */
-var JpxStream = (function JpxStreamClosure() {
-  function JpxStream(stream, maybeLength, dict, params) {
-    this.stream = stream;
-    this.maybeLength = maybeLength;
-    this.dict = dict;
-    this.params = params;
-
-    DecodeStream.call(this, maybeLength);
-  }
-
-  JpxStream.prototype = Object.create(DecodeStream.prototype);
-
-  Object.defineProperty(JpxStream.prototype, 'bytes', {
-    get: function JpxStream_bytes() {
-      // If this.maybeLength is null, we'll get the entire stream.
-      return shadow(this, 'bytes', this.stream.getBytes(this.maybeLength));
-    },
-    configurable: true,
-  });
-
-  JpxStream.prototype.ensureBuffer = function JpxStream_ensureBuffer(req) {
-    if (this.bufferLength) {
-      return;
-    }
-
-    var jpxImage = new JpxImage();
-    jpxImage.parse(this.bytes);
-
-    var width = jpxImage.width;
-    var height = jpxImage.height;
-    var componentsCount = jpxImage.componentsCount;
-    var tileCount = jpxImage.tiles.length;
-    if (tileCount === 1) {
-      this.buffer = jpxImage.tiles[0].items;
-    } else {
-      var data = new Uint8ClampedArray(width * height * componentsCount);
-
-      for (var k = 0; k < tileCount; k++) {
-        var tileComponents = jpxImage.tiles[k];
-        var tileWidth = tileComponents.width;
-        var tileHeight = tileComponents.height;
-        var tileLeft = tileComponents.left;
-        var tileTop = tileComponents.top;
-
-        var src = tileComponents.items;
-        var srcPosition = 0;
-        var dataPosition = (width * tileTop + tileLeft) * componentsCount;
-        var imgRowSize = width * componentsCount;
-        var tileRowSize = tileWidth * componentsCount;
-
-        for (var j = 0; j < tileHeight; j++) {
-          var rowBytes = src.subarray(srcPosition, srcPosition + tileRowSize);
-          data.set(rowBytes, dataPosition);
-          srcPosition += tileRowSize;
-          dataPosition += imgRowSize;
-        }
-      }
-      this.buffer = data;
-    }
-    this.bufferLength = this.buffer.length;
-    this.eof = true;
-  };
-
-  return JpxStream;
-})();
-
 var DecryptStream = (function DecryptStreamClosure() {
   function DecryptStream(str, maybeLength, decrypt) {
     this.str = str;
@@ -1414,8 +1251,6 @@ export {
   DecryptStream,
   DecodeStream,
   FlateStream,
-  JpegStream,
-  JpxStream,
   NullStream,
   PredictorStream,
   RunLengthStream,