Android Gallery

Module: LCKAndroidGallery | Version: 1.0 | Platforms: Android only

Overview

LCKAndroidGallery provides functions to save recorded videos and captured photos to the Android device’s media gallery. Files are published through the Android MediaStore API, making them visible in the device’s gallery app and accessible to other applications. Videos are saved to Movies/<GameName>/ and images to Pictures/<GameName>/, where <GameName> is read from your LCK project settings (falling back to the Unreal project name).

When to Use

Use these functions after:

A recording completes via StopRecording() or StopRecordingAsync() to save the video to the user’s gallery
A photo is captured via TakePhoto() to save the image to the user’s gallery

Files saved through LCKAndroidGallery appear immediately in the device gallery app. Without this step, recorded files remain in the app’s internal storage and are not visible to the user.

Functions

SaveVideoToGallery

Copies a video file to the Android MediaStore and reports copy progress via a callback.

LCKANDROIDGALLERY_API void SaveVideoToGallery(
    const FString& VideoPath,
    TFunction<void(float)> OnProgress
);

Parameter	Type	Description
`VideoPath`	`const FString&`	Absolute path to the source video file (`.mp4`)
`OnProgress`	`TFunction<void(float)>`	Callback invoked during the file copy with progress from `0.0` to `1.0`

The video is saved to Movies/<GameName>/<GameName>_<timestamp>.mp4 in the device’s shared storage.

SaveImageToGallery

Copies an image file to the Android MediaStore.

LCKANDROIDGALLERY_API void SaveImageToGallery(const FString& ImagePath);

Parameter	Type	Description
`ImagePath`	`const FString&`	Absolute path to the source image file (`.png`)

The image is saved to Pictures/<GameName>/<GameName>_<timestamp>.png in the device’s shared storage.

Usage Examples

Save Video After Recording

On Android, the encoder’s Save() method automatically calls SaveVideoToGallery() internally. You do not need to call it manually — the video is saved to the Android MediaStore (Gallery) as part of ReleaseEncoder(bSaveFile = true) or StopRecordingAsync(). The temp file is located at FPaths::ProjectPersistentDownloadDir() / TEXT("lck.mp4").

If you need to save a video file manually (e.g., from a custom location):

// The temp recording file location
FString TempVideoPath = FPaths::Combine(
    FPaths::ProjectPersistentDownloadDir(), TEXT("lck.mp4"));

// Save to Android gallery with progress tracking
SaveVideoToGallery(TempVideoPath,
    [](float Progress) {
        UE_LOG(LogTemp, Log, TEXT("Gallery save progress: %.0f%%"),
            Progress * 100.0f);
    }
);

Save Photo After Capture

// After taking a photo, save it to the gallery
// Photos are saved to the platform-specific pictures directory
if (Recorder->TakePhoto())
{
    // The photo path follows the pattern: Pictures/<GameName>/<GameName>_<timestamp>.png
    FString ImagePath = FPaths::Combine(
        FPaths::ProjectPersistentDownloadDir(), TEXT("photo.png"));
    SaveImageToGallery(ImagePath);
}

Platform Notes

LCKAndroidGallery is Android only. These functions use JNI to interact with the Android MediaStore API and will not compile on other platforms. Guard calls with platform checks if your project targets multiple platforms.

#if PLATFORM_ANDROID
    SaveVideoToGallery(VideoPath, OnProgress);
#endif

Permissions

LCKAndroidGallery uses the Android MediaStore ContentResolver API (available on Android 10 / API 29+), which does not require runtime storage permissions for writing to shared media directories. For devices running Android 9 (API 28) or earlier, you need:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

If your project targets API 29+, no additional permissions are needed. The MediaStore API handles scoped storage access automatically.

File Naming

Saved files follow the naming convention:

<GameName>_<YYYY-MM-DD_HH-MM-SS>.<ext>

The game name is resolved from your LCK project settings (GameName in LCKSettings). If not configured, the Unreal project name is used as a fallback.

Dependencies

// Add to your .Build.cs
PublicDependencyModuleNames.AddRange(new string[] {
    "LCKAndroidGallery"
});

Log Category

DECLARE_LOG_CATEGORY_EXTERN(LogLCKGallery, Log, All);

Troubleshooting

File does not appear in gallery

Verify the source file path exists before calling the save function
Check LogLCKGallery for error messages
Ensure the device is running Android 10+ or that WRITE_EXTERNAL_STORAGE permission is granted

Save fails with JNI error

Confirm you are calling from the game thread
Check that the Android activity is valid and not suspended
Review logcat output for Java exceptions

Progress callback not firing

Verify the OnProgress callback is valid (not null)
The callback fires per 4KB chunk — very small files may complete in a single call

Recording

Recording subsystem and lifecycle

Core SDK Overview

SDK architecture and modules

Core SDK

Tablet Interface

Tablet Customization

Audio

Streaming

API Reference

Overview

When to Use

Functions

SaveVideoToGallery

SaveImageToGallery

Usage Examples

Save Video After Recording

Save Photo After Capture

Platform Notes

Permissions

File Naming

Dependencies

Log Category

Troubleshooting

See Also

Recording

Core SDK Overview

​Overview

​When to Use

​Functions

​SaveVideoToGallery

​SaveImageToGallery

​Usage Examples

​Save Video After Recording

​Save Photo After Capture

​Platform Notes

​Permissions

​File Naming

​Dependencies

​Log Category

​Troubleshooting

​See Also

Recording

Core SDK Overview

Overview

When to Use

Functions

SaveVideoToGallery

SaveImageToGallery

Usage Examples

Save Video After Recording

Save Photo After Capture

Platform Notes

Permissions

File Naming

Dependencies

Log Category

Troubleshooting

See Also