How do I on the Android platform What about using a wide-angle camera

[menghengmen]

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How do I on the Android platform
What about using a wide-angle camera

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[UltralyticsAssistant]

👋 Hello @menghengmen, thank you for submitting a ultralytics/yolo-flutter-app 🚀 issue. This is an automated response to help us triage your request quickly, and an Ultralytics engineer will also assist soon 🤖✨

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[pderrenger]

On Android, the current CameraX integration in this repo selects cameras by front/back lens facing, not by a specific ultra-wide camera ID, so wide-angle support is not built in and would need a small native CameraX customization in the Android layer; YOLO can still run on a wide-angle feed, but distortion correction/calibration is recommended for best results with wide lenses, as covered in this camera calibration guide.

[menghengmen]

Is there a corresponding demo available. Thank you

[pderrenger]

There isn’t a dedicated wide-angle demo in this repo right now, but the app can work with one after a small Android CameraX change to select the ultra-wide lens; if helpful, I can share the minimal patch, and this camera calibration guide explains the distortion correction usually needed with wide lenses.

[menghengmen]

i need you minimal patch,thanks

[pderrenger]

Sure — the current Android code in YOLOView.kt selects the camera by lensFacing, and the Android module already includes CameraX Camera2 support, so this is the smallest patch to make the back camera prefer the shortest-focal-length rear lens instead. (github.com)

import android.hardware.camera2.CameraCharacteristics
import androidx.camera.camera2.interop.Camera2CameraInfo

// replace the current cameraSelector block in startCamera() with this
val cameraSelector = if (lensFacing == CameraSelector.LENS_FACING_BACK) {
    val wideCamera = cameraProvider.availableCameraInfos
        .filter {
            Camera2CameraInfo.from(it).getCameraCharacteristic(CameraCharacteristics.LENS_FACING) ==
                CameraCharacteristics.LENS_FACING_BACK
        }
        .minByOrNull {
            Camera2CameraInfo.from(it)
                .getCameraCharacteristic(CameraCharacteristics.LENS_INFO_AVAILABLE_FOCAL_LENGTHS)
                ?.minOrNull() ?: Float.MAX_VALUE
        }

    if (wideCamera != null) {
        CameraSelector.Builder()
            .addCameraFilter { infos -> infos.filter { it == wideCamera } }
            .build()
    } else {
        CameraSelector.DEFAULT_BACK_CAMERA
    }
} else {
    CameraSelector.DEFAULT_FRONT_CAMERA
}

[menghengmen]

Do I need to modify the source code of your warehouse？

[pderrenger]

Yes — for now you’ll need to modify the Android source in this repo or use your own fork/local package, since wide-angle camera selection is not exposed by the Flutter API yet; if you’d like to contribute that as a reusable option, please see the Ultralytics contributing guide.

[menghengmen]

I've been trying for some time, but perhaps my skills are limited and I'm still unable to do it. Could you, as the official team, please provide some assistance and support? Thank you

[pderrenger]

We’re happy to help here in the issue, but we can’t provide private 1:1 support; please first verify this still happens with the latest package, then paste your current YOLOView.kt changes and the exact build/runtime error or a small reproducible example so we can point you to the specific fix, and this Minimum Reproducible Example guide shows the best format.

[glenn-jocher]

Thanks for trying the patch. The current Android implementation still only exposes front/back selection from Flutter; internally YOLOView.startCamera() builds a CameraX selector with requireLensFacing(lensFacing), so ultra-wide selection requires changing the native Android camera selector or adding a new Flutter-facing option.

For us to help with the exact failure, please paste:

1. Your modified android/src/main/kotlin/com/ultralytics/yolo/YOLOView.kt camera selector block.
2. The exact Android build error or runtime logcat error.
3. Your phone model and Android version.

Without those details we can only give general guidance, because CameraX exposes multi-camera / ultra-wide lenses differently across Android devices. Longer term, the clean repo-level fix would be a feature PR that adds an explicit camera lens preference, such as back, front, and backWide, then falls back to the default back camera when no ultra-wide lens is available.