diff --git a/lib/media/data-utils.js b/lib/media/data-utils.js
new file mode 100644
--- /dev/null
+++ b/lib/media/data-utils.js
@@ -0,0 +1,92 @@
+// @flow
+
+import { fileInfoFromData } from './file-utils.js';
+
+/**
+ * Returns a hex string representation of the given Uint8Array.
+ */
+function uintArrayToHexString(data: Uint8Array): string {
+  return Array.from(data)
+    .map(byte => byte.toString(16).padStart(2, '0'))
+    .join('');
+}
+
+/**
+ * Returns a Uint8Array representation of the given hex string.
+ */
+function hexToUintArray(hex: string): Uint8Array {
+  const result = new Uint8Array(hex.length / 2);
+  for (let i = 0; i < hex.length; i += 2) {
+    result[i / 2] = parseInt(hex.substr(i, 2), 16);
+  }
+  return result;
+}
+
+/**
+ * Returns a data URL representation of the given Uint8Array.
+ * Returns `null` if MIME type cannot be determined by reading the data header.
+ */
+function uintArrayToDataURL(bytes: Uint8Array): ?string {
+  const base64 = base64FromIntArray(bytes);
+  const { mime } = fileInfoFromData(bytes);
+  if (!mime) {
+    return null;
+  }
+  return `data:${mime};base64,${base64}`;
+}
+
+/**
+ * Converts a Uint8Array to a base64 string. This is a temporary workaround
+ * until we can use implement native method to directly save Uint8Array to file.
+ *
+ * It is ~4-6x faster than using
+ * ```js
+ * let base64 = await blobToDataURI(new Blob([bytes]));
+ * base64 = base64.substring(base64.indexOf(',') + 1);
+ * ```
+ *
+ * This function based on
+ * - https://developer.mozilla.org/en-US/docs/Glossary/Base64
+ * - https://gist.github.com/jonleighton/958841
+ * - https://stackoverflow.com/a/12713326
+ */
+function base64FromIntArray(bytes: Uint8Array): string {
+  let base64 = '';
+  const alphabet =
+    'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/';
+
+  const remainder = bytes.length % 3;
+  const mainLength = bytes.length - remainder;
+
+  let a, b, c, d;
+  let chunk;
+  for (let i = 0; i < mainLength; i += 3) {
+    chunk = (bytes[i] << 16) | (bytes[i + 1] << 8) | bytes[i + 2];
+    a = (chunk & 16515072) >> 18;
+    b = (chunk & 258048) >> 12;
+    c = (chunk & 4032) >> 6;
+    d = chunk & 63;
+    base64 += alphabet[a] + alphabet[b] + alphabet[c] + alphabet[d];
+  }
+
+  if (remainder === 1) {
+    chunk = bytes[mainLength];
+    a = (chunk & 252) >> 2;
+    b = (chunk & 3) << 4;
+    base64 += alphabet[a] + alphabet[b] + '==';
+  } else if (remainder === 2) {
+    chunk = (bytes[mainLength] << 8) | bytes[mainLength + 1];
+    a = (chunk & 64512) >> 10;
+    b = (chunk & 1008) >> 4;
+    c = (chunk & 15) << 2;
+    base64 += alphabet[a] + alphabet[b] + alphabet[c] + '=';
+  }
+  return base64;
+}
+
+export {
+  uintArrayToHexString,
+  hexToUintArray,
+  base64FromIntArray,
+  uintArrayToDataURL,
+};
diff --git a/lib/media/data-utils.test.js b/lib/media/data-utils.test.js
new file mode 100644
--- /dev/null
+++ b/lib/media/data-utils.test.js
@@ -0,0 +1,42 @@
+// @flow
+import {
+  uintArrayToHexString,
+  hexToUintArray,
+  uintArrayToDataURL,
+} from './data-utils.js';
+
+describe('uintArrayToHexString', () => {
+  it('converts Uint8Array to hex string', () => {
+    const data = new Uint8Array([0x00, 0x01, 0x02, 0x1a, 0x2b, 0xff]);
+    expect(uintArrayToHexString(data)).toStrictEqual('0001021a2bff');
+  });
+});
+
+describe('hexToUintArray', () => {
+  it('converts hex string to Uint8Array', () => {
+    const hex = '0001021a2bff';
+    expect(hexToUintArray(hex)).toStrictEqual(
+      new Uint8Array([0x00, 0x01, 0x02, 0x1a, 0x2b, 0xff]),
+    );
+  });
+});
+
+describe('uintArrayToDataURL', () => {
+  it('converts JPEG Uint8Array to data URL', () => {
+    const jpegMagicBytes = new Uint8Array([0xff, 0xd8, 0xff, 0xe0]);
+    const jpegData = new Uint8Array(jpegMagicBytes.length + 10);
+    jpegData.set(jpegMagicBytes);
+    jpegData.set(
+      new Uint8Array([0x00, 0x10, 0x4a, 0x46, 0x49, 0x46, 0x00, 0x01]),
+      jpegMagicBytes.length,
+    );
+
+    const jpegBase64 = 'data:image/jpeg;base64,/9j/4AAQSkZJRgABAAA=';
+    expect(uintArrayToDataURL(jpegData)).toStrictEqual(jpegBase64);
+  });
+
+  it('returns null if MIME type cannot be determined', () => {
+    const data = new Uint8Array([0x00, 0x01, 0x02, 0x1a, 0x2b, 0xff]);
+    expect(uintArrayToDataURL(data)).toBeNull();
+  });
+});