Android byte[] to image in Camera.onPreviewFrame

Question

When trying to convert the byte[] of Camera.onPreviewFrame to Bitamp using BitmapFactory.decodeByteArray gives me an error SkImageDecoder::Factory returned null

Following is my code:

public void onPreviewFrame(byte[] data, Camera camera) {
    Bitmap bmp=BitmapFactory.decodeByteArray(data, 0, data.length);
}

Answer 1

This has been hard to find! But since API 8, there is a YuvImage class in android.graphics. It's not an Image descendent, so all you can do with it is save it to Jpeg, but you could save it to memory stream and then load into Bitmap Image if that's what you need.

import android.graphics.YuvImage;

@Override
public void onPreviewFrame(byte[] data, Camera camera) {
    try {
        Camera.Parameters parameters = camera.getParameters();
        Size size = parameters.getPreviewSize();
        YuvImage image = new YuvImage(data, parameters.getPreviewFormat(),
                size.width, size.height, null);
        File file = new File(Environment.getExternalStorageDirectory()
                .getPath() + "/out.jpg");
        FileOutputStream filecon = new FileOutputStream(file);
        image.compressToJpeg(
                new Rect(0, 0, image.getWidth(), image.getHeight()), 90,
                filecon);
    } catch (FileNotFoundException e) {
        Toast toast = Toast
                .makeText(getBaseContext(), e.getMessage(), 1000);
        toast.show();
    }
}

Answer 2

Since Android 3.0 you can use a TextureView and TextureSurface to display the camera, and then use mTextureView.getBitmap() to retrieve a friendly RGB preview frame.

A very skeletal example of how to do this is given in the TextureView docs. Note that you'll have to set your application or activity to be hardware accelerated by putting android:hardwareAccelerated="true" in the manifest.