Imagine we try to run this project in the web, iOS or macOS. Likely, a Not Supported error will be thrown.

With a pure dart implementation of this, we could make this work for every platform. I am not saying to remove the native implementation, since they're faster than Dart, I'm saying to support all the platforms, regardless of how fast it is.

This could be done through ffi and add a pure dart implementation for the web, or just don't provide web support (I don't see how web apps would be manipulating media files, and if they do, that'd be uneffectively).

great project btw :)

When requesting meta data for a list of files the meta data gets mixed up. The MetaDataRetriever quite often returns the same meta data twice or thrice or scrambles together a completly new set of meta data.

A quick but dirty fix is delaying each meta data request by a 100ms.

When I use the following code, the continuation of the code stops without any error await MetadataRetriever.fromFile(File(songInfo.filePath));

I tried to find the library problem to fix it I noticed that an error occurs when using setFilePath (retriever.setFilePath(filePath);) This function gives java.lang.IllegalArgumentException error without any message

I don't own a mac or an iOS device.

There are some people out there, who wanna use this plugin on iOS devices.

Any Objective-C or Swift geek is free to add iOS support to this plugin.

Thanks. My appreciation, if you decide to help out.

According to CompletableFuture CompletableFuture is Added in [API level 24]

If app imported this package build with minSdkVersion less than [API level 24], app would run into this error

Fatal Exception: java.lang.NoClassDefFoundError
Failed resolution of: Ljava/util/concurrent/CompletableFuture;

Caused by java.lang.ClassNotFoundException
Didn't find class "java.util.concurrent.CompletableFuture" 

So this PR is needed to support lower API level, which referred from the flutter official plugin https://github.com/flutter/plugins/commit/0bd38d2a2cf367e2418334bd32d362c1880704be

When attempting to run a flutter app that uses flutter_media_metadata on Linux, the compilation of the application fails.

Launching lib/main.dart on Linux in debug mode...
[/home/abitofevrything/Programming/music_player/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/cxx/utils.hpp:108:12](): warning: variable 'last_index' set but not used [-Wunused-but-set-variable]
[/home/abitofevrything/Programming/music_player/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/cxx/metadata_retriever.cpp:56:16](): warning: variable 'size' set but not used [-Wunused-but-set-variable]
[/home/abitofevrything/Programming/music_player/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/cxx/metadata_retriever.cpp:57:16](): warning: variable 'header' set but not used [-Wunused-but-set-variable]
clang-13: error: linker command failed with exit code 1 (use -v to see invocation)
Exception: Build process failed

[✓] Flutter (Channel stable, 2.10.2, on Artix Linux 5.16.10-artix1-1, locale en_GB.UTF-8)
    • Flutter version 2.10.2 at /opt/flutter
    • Upstream repository https://github.com/flutter/flutter.git
    • Framework revision 097d3313d8 (12 days ago), 2022-02-18 19:33:08 -0600
    • Engine revision a83ed0e5e3
    • Dart version 2.16.1
    • DevTools version 2.9.2

[✗] Android toolchain - develop for Android devices
    ✗ ANDROID_HOME = /opt/android-sdk
      but Android SDK not found at this location.

[✓] Chrome - develop for the web
    • CHROME_EXECUTABLE = chromium

[✓] Linux toolchain - develop for Linux desktop
    • clang version 13.0.1
    • cmake version 3.22.2
    • ninja version 1.10.2
    • pkg-config version 1.8.0

[!] Android Studio (not installed)
    • Android Studio not found; download from https://developer.android.com/studio/index.html
      (or visit https://flutter.dev/docs/get-started/install/linux#android-setup for detailed instructions).

[✓] Connected device (2 available)
    • Linux (desktop) • linux  • linux-x64      • Artix Linux 5.16.10-artix1-1
    • Chrome (web)    • chrome • web-javascript • Chromium 98.0.4758.102 Arch Linux

[✓] HTTP Host Availability
    • All required HTTP hosts are available

! Doctor found issues in 2 categories.

Fatal Exception: java.lang.NoClassDefFoundError Failed resolution of: Ljava/util/concurrent/CompletableFuture;

java.lang.ClassLoader.loadClass (ClassLoader.java:469) com.alexmercerind.flutter_media_metadata.a.onMethodCall (FlutterMediaMetadataPlugin.java:2) io.flutter.plugin.common.MethodChannel$IncomingMethodCallHandler.onMessage (MethodChannel.java:2) io.flutter.embedding.engine.dart.DartMessenger.invokeHandler (DartMessenger.java:2) io.flutter.embedding.engine.dart.DartMessenger.a (DartMessenger.java:2) io.flutter.embedding.engine.dart.DartMessenger.b (DartMessenger.java) io.flutter.embedding.engine.dart.c.run (lambda) android.os.Handler.handleCallback (Handler.java:739)

Not support CompletableFuture while android's minSdk is less than 24

It is similar to an flutter/plugin issue.

The solution can be refer to https://github.com/flutter/plugins/pull/2770/commits/0bd38d2a2cf367e2418334bd32d362c1880704be

Hello, I am having a problem that this package gives an error no such method (MetadataRetriever) defined in channel when I put the path of an audio file of my phone which is connected to my dekstop through USB.

Hello! Your library works on Android very well & it's amazing. But, if I build for Linux, I get this strange error.

[        ] /home/mytja/Documents/harmonoid/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/linux/include/flutter_media_metadata/flutter_types.hpp:22:10: error: explicit specialization of
'returnValue' in class scope
[   +1 ms]     void returnValue<int>(int result) {
[        ]          ^
[        ] /home/mytja/Documents/harmonoid/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/linux/include/flutter_media_metadata/flutter_types.hpp:33:10: error: explicit specialization of
'returnValue' in class scope
[   +1 ms]     void returnValue<std::string>(std::string result) {
[        ]          ^
[        ] /home/mytja/Documents/harmonoid/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/linux/include/flutter_media_metadata/flutter_types.hpp:45:10: error: explicit specialization of
'returnValue' in class scope
[        ]     void returnValue<std::map<std::string, std::string>>(std::map<std::string, std::string> result) {
[        ]          ^
[        ] /home/mytja/Documents/harmonoid/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/linux/include/flutter_media_metadata/flutter_types.hpp:79:9: error: explicit specialization of
'getArgument' in class scope
[        ]     int getArgument<int>(const char* argument) {
[        ]         ^
[        ] /home/mytja/Documents/harmonoid/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/linux/include/flutter_media_metadata/flutter_types.hpp:89:17: error: explicit specialization of
'getArgument' in class scope
[        ]     std::string getArgument<std::string>(const char* argument) {
[        ]                 ^
[        ] /home/mytja/Documents/harmonoid/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/linux/include/flutter_media_metadata/flutter_types.hpp:101:11: error: explicit specialization of
'getArgument' in class scope
[        ]     float getArgument<float>(const char* argument) {
[        ]           ^

Do you know what could be wrong??? Thank you so much

this line throw such error await retriever.setFile(File(song.path));

[ERROR:flutter/runtime/dart_isolate.cc(1137)] Unhandled exception:
Null check operator used on a null value
#0      MethodChannel.binaryMessenger
package:flutter/…/services/platform_channel.dart:142
#1      MethodChannel._invokeMethod
package:flutter/…/services/platform_channel.dart:148
#2      MethodChannel.invokeMethod
package:flutter/…/services/platform_channel.dart:331
#3      MetadataRetriever.setFile
package:flutter_media_metadata/flutter_media_metadata.dart:85
<asynchronous suspension>
#4      GenerateThumbnails.isolatedThread
package:ruminate/…/utils/generate_thumbnails.dart:38
<asynchronous suspension>

dart version sdk: '>=2.13.0 <3.0.0'

That is when you have a listview where for each item you are trying to fetch album art, if queries are done simulatniously, multiple items will eventaually receive same data.

I created a repro for this, see #10

when using in isolate this error happen try adding WidgetsFlutterBinding.ensureInitialized() in main method but not fix.

Binding has not yet been initialized. The "instance" getter on the ServicesBinding binding mixin is only available once that binding has been initialized. Typically, this is done by calling "WidgetsFlutterBinding.ensureInitialized()" or "runApp()" (the latter calls the former). Typically this call is done in the "void main()" method. The "ensureInitialized" method is idempotent; calling it multiple times is not harmful. After calling that method, the "instance" getter will return the binding. In a test, one can call "TestWidgetsFlutterBinding.ensureInitialized()" as the first line in the test's "main()" method to initialize the binding.

Hi,

Following piece of code:

FilePickerResult? result = await FilePicker.platform.pickFiles(allowMultiple: true);
  if (result != null) {
  for(int x = 0; x < result.files.length; x++) {
    print(result.files[x].name);
    Uint8List bytes = result.files[x].bytes as Uint8List;
    final metadata = await MetadataRetriever.fromBytes(bytes); // throws the error
    String? trackName = metadata.trackName;
    print(trackName);

[...]

I checked this with mp3, m4a and wmv files. It only occurs on Flutter web. If the audio files contain an album art everything works fine. If they do not contain an album art, I get the following error message:

Error: Expected a value of type 'String', but got one of type 'Null' at Object.throw_ [as throw] (http://localhost:50323/dart_sdk.js:5067:11) at Object.castError (http://localhost:50323/dart_sdk.js:5026:15) at Object.cast [as as] (http://localhost:50323/dart_sdk.js:5351:17) at Function.as (http://localhost:50323/dart_sdk.js:46170:19) at http://localhost:50323/packages/flutter_media_metadata/src/flutter_media_metadata_web.dart.lib.js:89:159 at Object._checkAndCall (http://localhost:50323/dart_sdk.js:5274:16) at Object.dcall (http://localhost:50323/dart_sdk.js:5279:17) at ret (http://localhost:50323/dart_sdk.js:62346:21)

Afaik this relates to the following line of code:

let metadata = new (T.IdentityMapOfString$dynamic()).from(["metadata", new _js_helper.LinkedMap.new(), "albumArt", convert.base64Decode(core.String.as(dart.dsend(rawMetadataJson, '_get', ["Cover_Data"]))), "filePath", null]);

I cannot read nor write .js :) but it looks like a null check is missing?

What else do you need?

Thanks, Michael

Cannot build my project on Linux.

flutter run -d linux:

/home/pizi/Documents/Project/boombox/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/cxx/utils.hpp:108:12: error: variable 'last_index' set but not used [-Werror,-Wunused-but-set-variable]
/home/pizi/Documents/Project/boombox/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/cxx/metadata_retriever.cpp:56:16: error: variable 'size' set but not used [-Werror,-Wunused-but-set-variable]
/home/pizi/Documents/Project/boombox/linux/flutter/ephemeral/.plugin_symlinks/flutter_media_metadata/cxx/metadata_retriever.cpp:57:16: error: variable 'header' set but not used [-Werror,-Wunused-but-set-variable]
Exception: Build process failed

flutter doctor:

[✓] Flutter (Channel stable, 2.10.4, on Manjaro Linux 5.15.28-1-MANJARO, locale
    en_US.UTF-8)
[✓] Android toolchain - develop for Android devices (Android SDK version
    32.1.0-rc1)
[✓] Chrome - develop for the web
[✓] Linux toolchain - develop for Linux desktop
[✓] Android Studio (version 2021.1)
[✓] Connected device (2 available)
[✓] HTTP Host Availability

tried as per #23, still not working

mediainfo --version

MediaInfo Command line, 
MediaInfoLib - v22.03

Uint8List byteString = await pickedFile.readAsBytes(); <<pickedFile is XFile Metadata videoMetaData = await MetadataRetriever.fromBytes(byteString); int? dur = videoMetaData.trackDuration; << returns null

Note: I have added this script in the section of index.html

also the code crashes on this line line 110 of flutter_media_metadata_web.dart:'albumArt': base64Decode(rawMetadataJson['Cover_Data']),

I'm basically struggling to get the duration of a picked video file on the web.