FISHEYE_RAMP_WIDTH should be in DP instead of pixels.

import android.os.HandlerThread;

import android.os.Message;

import android.util.Log;

import android.util.TypedValue;

import android.view.ContextThemeWrapper;

import android.view.Display;

import android.view.PixelCopy;

    // the Handler of this Thread when the copy is finished.

    private static final HandlerThread sPixelCopyHandlerThread =

            new HandlerThread("magnifier pixel copy result handler");

    // The width of the ramp region in pixels on the left & right sides of the fish-eye effect.

    private static final int FISHEYE_RAMP_WIDTH = 30;

    // The width of the ramp region in DP on the left & right sides of the fish-eye effect.

    private static final float FISHEYE_RAMP_WIDTH = 12f;

    // The view to which this magnifier is attached.

    private final View mView;

    // The horizontal bounds of the content source in pixels, relative to the view.

    private int mLeftBound = Integer.MIN_VALUE;

    private int mRightBound = Integer.MAX_VALUE;

    // The width of the ramp region in pixels on the left & right sides of the fish-eye effect.

    private final int mRamp;

    /**

     * Initializes a magnifier.

        mBottomContentBound = params.mBottomContentBound;

        // The view's surface coordinates will not be updated until the magnifier is first shown.

        mViewCoordinatesInSurface = new int[2];

        mRamp = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, FISHEYE_RAMP_WIDTH,

                mView.getContext().getResources().getDisplayMetrics());

    }

    static {

            // content. However the PixelCopy requires the pre-magnified bounds.

            // The below logic calculates the leftBound & rightBound for the pre-magnified bounds.

            final float rampPre =

                    (mSourceWidth - (mSourceWidth - 2 * FISHEYE_RAMP_WIDTH) / mZoom) / 2;

                    (mSourceWidth - (mSourceWidth - 2 * mRamp) / mZoom) / 2;

            // Calculates the pre-zoomed left edge.

            // The leftEdge moves from the left of view towards to sourceCenterX, considering the

            // fisheye-like zooming.

            final float x0 = sourceCenterX - mSourceWidth / 2;

            final float rampX0 = x0 + FISHEYE_RAMP_WIDTH;

            final float rampX0 = x0 + mRamp;

            float leftEdge = 0;

            if (leftEdge > rampX0) {

                // leftEdge is in the zoom range, the distance from leftEdge to sourceCenterX

            } else if (leftEdge > x0) {

                // leftEdge is in the ramp range, the distance from leftEdge to rampX0 should

                // increase per ramp zoom (ramp / rampPre).

                leftEdge = x0 + rampPre - (rampX0 - leftEdge) * rampPre / FISHEYE_RAMP_WIDTH;

                leftEdge = x0 + rampPre - (rampX0 - leftEdge) * rampPre / mRamp;

            }

            int leftBound = Math.min(Math.max((int) leftEdge, mLeftBound), mRightBound);

            // The rightEdge moves from the right of view towards to sourceCenterX, considering the

            // fisheye-like zooming.

            final float x1 = sourceCenterX + mSourceWidth / 2;

            final float rampX1 = x1 - FISHEYE_RAMP_WIDTH;

            final float rampX1 = x1 - mRamp;

            float rightEdge = mView.getWidth();

            if (rightEdge < rampX1) {

                // rightEdge is in the zoom range, the distance from rightEdge to sourceCenterX

            } else if (rightEdge < x1) {

                // rightEdge is in the ramp range, the distance from rightEdge to rampX1 should

                // increase per ramp zoom (ramp / rampPre).

                rightEdge = x1 - rampPre + (rightEdge - rampX1) * rampPre / FISHEYE_RAMP_WIDTH;

                rightEdge = x1 - rampPre + (rightEdge - rampX1) * rampPre / mRamp;

            }

            int rightBound = Math.max(leftBound, Math.min((int) rightEdge, mRightBound));

                synchronized (mLock) {

                    mWindow = new InternalPopupWindow(mView.getContext(), mView.getDisplay(),

                            mParentSurface.mSurfaceControl, mWindowWidth, mWindowHeight, mZoom,

                            FISHEYE_RAMP_WIDTH, mWindowElevation, mWindowCornerRadius,

                            mRamp, mWindowElevation, mWindowCornerRadius,

                            mOverlay != null ? mOverlay : new ColorDrawable(Color.TRANSPARENT),

                            Handler.getMain() /* draw the magnifier on the UI thread */, mLock,

                            mCallback, mIsFishEyeStyle);