Get Bitmap from SurfaceView

Question

I need to convert my SurfaceView's content into a Bitmap. I tried to achieve this using the following code snippet inside the SurfaceView:

 public final Bitmap getScreenCopy() {
        Bitmap bitmap = Bitmap.createBitmap(
                getWidth(),
                getHeight(),
                Bitmap.Config.ARGB_8888
        );

        Canvas temporaryCanvas = new Canvas(bitmap);
        draw(temporaryCanvas); // Voodoo.

        return bitmap;
    }

The bitmap I receive from that drone seems to be transparent, does anyone know how to fix that?

Using a TextureView is not possible, since I use the Parrot SDK and the drone needs a SurfaceView to display the Frames.

Possible duplicate of [Android: creating a Bitmap with SurfaceView content](https://stackoverflow.com/questions/4742868/android-creating-a-bitmap-with-surfaceview-content) — AskNilesh, Feb 27 '18 at 08:39
https://stackoverflow.com/questions/14181498/getting-bitmap-from-custom-surfaceview — AskNilesh, Feb 27 '18 at 08:40

score 2 · Answer 1 · answered Dec 06 '18 at 02:33

I've been trying to find a way to achieve this too and so far I haven't found a way to do it for devices with API level below 24. I tried messing with the drawing cache, but I get nothing but transparency. I didn't expect the drawingCache approach to work anyway due to the fact that the view itself draws nothing and everything goes onto the Surface.

For API levels 24 and newer, you can use the PixelCopy APIs to copy all or a portion of the SurfaceView into a bitmap.

Here's a snippet from my (Kotlin) code:

override fun getPlotBitmap(view: PlotSurfaceView) = Single.create<Bitmap> {
    val plotBitmap = Bitmap.createBitmap(view.width, view.height, Bitmap.Config.ARGB_8888)

    val listener = PixelCopy.OnPixelCopyFinishedListener { copyResult ->
        when (copyResult) {
            PixelCopy.SUCCESS -> {
                it.onSuccess(plotBitmap)
            }
            else -> {
                it.onError(RuntimeException("Pixel copy failed with result $copyResult"))
            }
        }
    }

    PixelCopy.request(view, plotBitmap, listener, view.handler)
}

Get Bitmap from SurfaceView

1 Answers1