Fix for m4a files as audio/mp4. Up-rev to 1.1.2.

Author: codedread

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All notable changes to this project will be documented in this file.
 
+## [1.1.2] - 2023-09-30
+
+- codecs: Handle m4a files as audio/mp4.
+
 ## [1.1.1] - 2023-06-21
 
 - Fix missing RarVM import in unrar.js.

codecs/codecs.js

@@ -58,6 +58,11 @@ export function getShortMIMEString(info) {
     return 'audio/flac';
   }
 
+  // M4A files are specifically audio/mp4.
+  if (info?.format?.filename?.toLowerCase().endsWith('.m4a')) {
+    return 'audio/mp4';
+  }
+
   // Otherwise, any file with at least 1 video stream is considered video/.
   // Otherwise, any file with at least 1 audio stream is considered audio/.
   const type = info.streams.some(s => s.codec_type === 'video') ?

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "@codedread/bitjs",
-  "version": "1.1.1",
+  "version": "1.1.2",
   "description": "Binary Tools for JavaScript",
   "homepage": "https://github.com/codedread/bitjs",
   "author": "Jeff Schiller",

package.json

@@ -75,6 +75,13 @@ describe('codecs test suite', () => {
       })).equals('audio/mpeg');
     });
 
+    it('detects M4A audio', () => {
+      expect(getShortMIMEString({
+        format: { filename: 'sample.m4a', format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
+        streams: [ { codec_type: 'video', }, { codec_type: 'audio' } ],
+      })).equals('audio/mp4');
+    });
+
     it('detects MP4 video', () => {
       expect(getShortMIMEString({
         format: { format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
@@ -306,24 +313,21 @@ describe('codecs test suite', () => {
 
   describe('MP4A / AAC', () => {
     /** @type {ProbeInfo} */
-    let info;
-
-    beforeEach(() => {
-      info = {
-        format: { format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
-        streams: [{
-          codec_type: 'audio',
-          codec_tag_string: 'mp4a',
-        }],
-      };
-    });
+    let baseInfo = {
+      format: { format_name: 'mov,mp4,m4a,3gp,3g2,mj2' },
+      streams: [{
+        codec_type: 'audio',
+        codec_tag_string: 'mp4a',
+      }],
+    };
 
     it('throws when unknown', () => {
-      expect(() => getFullMIMEString(info)).to.throw();
+      expect(() => getFullMIMEString(baseInfo)).to.throw();
     });
 
     describe('Profile tests', () => {
       it('recognizes AAC-LC', () => {
+        const info = structuredClone(baseInfo);
         info.streams[0].profile = 'LC';
         expect(getFullMIMEString(info))
             .to.be.a('string')
@@ -332,13 +336,24 @@ describe('codecs test suite', () => {
     });
 
     it('handles codec_name=aac but no codec_tag_string', () => {
+      const info = structuredClone(baseInfo);
       info.streams[0].profile = 'LC';
       info.streams[0].codec_tag_string = '[0][0][0][0]';
       info.streams[0].codec_name = 'aac';
       expect(getFullMIMEString(info))
           .to.be.a('string')
           .and.equals('audio/mp4; codecs="mp4a.40.2"');
     });
+
+    it('handles m4a file with MJPEG stream', () => {
+      const info = structuredClone(baseInfo);
+      info.format.filename = 'sample.m4a';
+      info.streams[0].profile = 'LC';
+      info.streams.push({codec_name: 'mjpeg', codec_type: 'video', profile: 'Baseline'});
+      expect(getFullMIMEString(info))
+          .to.be.a('string')
+          .and.equals('audio/mp4; codecs="mp4a.40.2"');
+    })
   });
 
   describe('MP4 / FLAC', () => {
@@ -374,7 +389,7 @@ describe('codecs test suite', () => {
       expect(getFullMIMEString(vInfo))
           .to.be.a('string')
           .and.equals('video/mp4; codecs="flac"');
-      
+
     });
   });