Added 'isImage' and 'isType' functions

src/core/lib/FileType.mjs

@@ -703,6 +703,39 @@ export function detectFileType(buf) {
 }
 
 
+/**
+ * Detects whether the given buffer is a file of the type specified.
+ *
+ * @param {string|RegExp} type
+ * @param {Uint8Array} buf
+ * @returns {string|false} The mime type or false if the type does not match
+ */
+export function isType(type, buf) {
+    const types = detectFileType(buf);
+
+    if (!(types && types.length)) return false;
+
+    if (typeof type === "string") {
+        return types[0].mime.startsWith(type) ? types[0].mime : false;
+    } else if (type instanceof RegExp) {
+        return type.test(types[0].mime) ? types[0].mime : false;
+    } else {
+        throw new Error("Invalid type input.");
+    }
+}
+
+
+/**
+ * Detects whether the given buffer contains an image file.
+ *
+ * @param {Uint8Array} buf
+ * @returns {string|false} The mime type or false if the type does not match
+ */
+export function isImage(buf) {
+    return isType("image", buf);
+}
+
+
 /**
  * Attempts to extract a file from a data stream given its offset and extractor function.
  *

src/core/operations/GenerateQRCode.mjs

@@ -8,7 +8,7 @@ import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import qr from "qr-image";
 import { toBase64 } from "../lib/Base64";
-import Magic from "../lib/Magic";
+import { isImage } from "../lib/FileType";
 import Utils from "../Utils";
 
 /**
@@ -100,9 +100,9 @@ class GenerateQRCode extends Operation {
 
         if (format === "PNG") {
             let dataURI = "data:";
-            const type = Magic.magicFileType(data);
+            const mime = isImage(data);
-            if (type && type.mime.indexOf("image") === 0){
+            if (mime){
-                dataURI += type.mime + ";";
+                dataURI += mime + ";";
             } else {
                 throw new OperationError("Invalid PNG file generated by QR image");
             }

src/core/operations/ParseQRCode.mjs

@@ -6,7 +6,7 @@
 
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
-import Magic from "../lib/Magic";
+import { isImage } from "../lib/FileType";
 import jsqr from "jsqr";
 import jimp from "jimp";
 
@@ -42,11 +42,11 @@ class ParseQRCode extends Operation {
      * @returns {string}
      */
     async run(input, args) {
-        const type = Magic.magicFileType(input);
         const [normalise] = args;
 
         // Make sure that the input is an image
-        if (type && type.mime.indexOf("image") === 0) {
+        if (!isImage(input)) throw new OperationError("Invalid file type.");
+
         let image = input;
 
         if (normalise) {
@@ -96,9 +96,6 @@ class ParseQRCode extends Operation {
                     reject(new OperationError("Error reading the image file."));
                 });
         });
-        } else {
-            throw new OperationError("Invalid file type.");
-        }
 
     }
 

src/core/operations/PlayMedia.mjs

@@ -9,7 +9,7 @@ import { fromHex } from "../lib/Hex";
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import Utils from "../Utils";
-import { detectFileType } from "../lib/FileType";
+import { isType, detectFileType } from "../lib/FileType";
 
 /**
  * PlayMedia operation
@@ -66,8 +66,7 @@ class PlayMedia extends Operation {
 
 
         // Determine file type
-        const types = detectFileType(input);
+        if (!isType(/^(audio|video)/, input)) {
-        if (!(types && types.length && /^audio|video/.test(types[0].mime))) {
             throw new OperationError("Invalid or unrecognised file type");
         }
 

src/core/operations/RenderImage.mjs

@@ -9,7 +9,7 @@ import { fromHex } from "../lib/Hex";
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import Utils from "../Utils";
-import {detectFileType} from "../lib/FileType";
+import {isImage} from "../lib/FileType";
 
 /**
  * Render Image operation
@@ -72,8 +72,7 @@ class RenderImage extends Operation {
         }
 
         // Determine file type
-        const types = detectFileType(input);
+        if (!isImage(input)) {
-        if (!(types.length && types[0].mime.indexOf("image") === 0)) {
             throw new OperationError("Invalid file type");
         }
 
@@ -92,9 +91,9 @@ class RenderImage extends Operation {
         let dataURI = "data:";
 
         // Determine file type
-        const types = detectFileType(data);
+        const mime = isImage(data);
-        if (types.length && types[0].mime.indexOf("image") === 0) {
+        if (mime) {
-            dataURI += types[0].mime + ";";
+            dataURI += mime + ";";
         } else {
             throw new OperationError("Invalid file type");
         }

src/core/operations/SplitColourChannels.mjs

@@ -7,7 +7,7 @@
 import Operation from "../Operation";
 import OperationError from "../errors/OperationError";
 import Utils from "../Utils";
-import Magic from "../lib/Magic";
+import {isImage} from "../lib/FileType";
 
 import jimp from "jimp";
 
@@ -38,9 +38,9 @@ class SplitColourChannels extends Operation {
      * @returns {List<File>}
      */
     async run(input, args) {
-        const type = Magic.magicFileType(input);
         // Make sure that the input is an image
-        if (type && type.mime.indexOf("image") === 0) {
+        if (!isImage(input)) throw new OperationError("Invalid file type.");
+
         const parsedImage = await jimp.read(Buffer.from(input));
 
         const red = new Promise(async (resolve, reject) => {
@@ -85,9 +85,6 @@ class SplitColourChannels extends Operation {
         });
 
         return await Promise.all([red, green, blue]);
-        } else {
-            throw new OperationError("Invalid file type.");
-        }
     }
 
     /**