Prevent flickering on camera preview update

Question

I am using the frames that I receive from a USB camera (Using the UVCCamera library) and I apply a blur effect using RenderScript. The frame format is NV21. The blur effect created by RenderScript works very nicely. However, when I want to apply other effects using Zomato Filters, I get a flickering result, although the effects are applied.

And then in the onFrame method, I get the frames from USB camera and apply filters according to seekbar values:

    private final IFrameCallback mIFrameCallback = new IFrameCallback() {
        @Override
        public void onFrame(final ByteBuffer frame) {
            frame.clear();
            synchronized (bitmap) {
//                bitmap.copyPixelsFromBuffer(frame);


                byte[] bytes = new byte[frame.remaining()];
                frame.get(bytes);
                MainActivity.this.allocationYUV.copyFrom(bytes);
                MainActivity.this.ApplyEffect = false;
                if (!MainActivity.this.ApplyEffect) {
                    MainActivity.this.intrinsicYuvToRGB.setInput(MainActivity.this.allocationYUV);
                    MainActivity.this.intrinsicYuvToRGB.forEach(MainActivity.this.allocationBlur);
                    MainActivity.this.intrinsicBlur.forEach(MainActivity.this.allocationBlur, MainActivity.this.allocationOut);                   

                }
                MainActivity.this.allocationOut.syncAll(128);

                //Here, apply the three other effects
                int brightness = mSeekbar1.getProgress();
                int contrast = mSeekbar2.getProgress();
                int saturation = mSeekbar3.getProgress();

                //The following checks are done to prevent unnecessary image processing
                Filter myFilter = new Filter();
                if(brightness != 0) {
                        BrightnessSubfilter bs = new BrightnessSubfilter(brightness * 32);
                        bs.setTag("brightness");
                        myFilter.addSubFilter(bs);
                }
                else { //If 0, then remove the filter altogether
                    myFilter.removeSubFilterWithTag("brightness");
                }
                if(contrast != 0) {
                        ContrastSubfilter cs = new ContrastSubfilter(contrast * 32);
                        cs.setTag("contrast");
                        myFilter.addSubFilter(cs);
                        mContrastChanged = false;
                }
                else {
                    myFilter.removeSubFilterWithTag("contrast");
                }

                if(saturation != 0) {
                        SaturationSubfilter ss = new SaturationSubfilter(saturation * 32);
                        ss.setTag("saturation");
                        myFilter.addSubFilter(ss);
                        mSaturationChanged = false;
                }
                else {
                    myFilter.removeSubFilterWithTag("saturation");
                }
                mOutBitmap = myFilter.processFilter(bitmap);

                mImageView.post(mUpdateImageTask);

            }
        }
    };

    private final Runnable mUpdateImageTask = new Runnable() {
        @Override
        public void run() {
            synchronized (bitmap) {
                mImageView.setImageBitmap(mOutBitmap);
            }
        }
    };

I think the RenderScript allocations for blurring is pretty typical, so I didn't add those to save space and reduce complexity.