圖像處理------邊緣褪化效果 分類： 視頻圖像處理 2015-07-24 09:54 30人閱讀 評論(0) 收藏

不少圖像處理軟件都提供邊緣褪化效果濾鏡，其實原理很是的簡單，網上搜索了一把，

實現了基於Java的圖像邊緣褪化效果。邊緣褪化效果取決於如下三個參數：

1.      設定的圖像邊緣寬度

2.      褪化比率– 其實質是圖像融合的百分比數

3.      選擇的邊框顏色

 

主要原理是計算圖像中的像素點到中心點的距離，對邊緣像素根據褪化比率與選擇的

邊框顏色融合從而產生褪化效果。程序效果以下：

原圖：

處理之後圖像：

濾鏡的徹底源代碼以下：

package com.process.blur.study;

import java.awt.Color;
import java.awt.image.BufferedImage;

/**
 * @author gloomy fish
 * Vignette - a photograph whose edges shade off gradually
 *
 */
public class VignetteFilter extends AbstractBufferedImageOp {

    private int vignetteWidth;
    private int fade;
    private Color vignetteColor;

    public VignetteFilter() {
        vignetteWidth = 50;
        fade = 35;
        vignetteColor = Color.BLACK;
    }

    @Override
    public BufferedImage filter(BufferedImage src, BufferedImage dest) {
        int width = src.getWidth();
        int height = src.getHeight();

        if ( dest == null )
            dest = createCompatibleDestImage( src, null );

        int[] inPixels = new int[width*height];
        int[] outPixels = new int[width*height];
        getRGB( src, 0, 0, width, height, inPixels );
        int index = 0;
        for(int row=0; row<height; row++) {
            int ta = 0, tr = 0, tg = 0, tb = 0;
            for(int col=0; col<width; col++) {

                int dX = Math.min(col, width - col);
                int dY = Math.min(row, height - row);
                index = row * width + col;
                ta = (inPixels[index] >> 24) & 0xff;
                tr = (inPixels[index] >> 16) & 0xff;
                tg = (inPixels[index] >> 8) & 0xff;
                tb = inPixels[index] & 0xff;
                if ((dY <= vignetteWidth) & (dX <= vignetteWidth))
                {
                    double k = 1 - (double)(Math.min(dY, dX) - vignetteWidth + fade) / (double)fade;
                    outPixels[index] = superpositionColor(ta, tr, tg, tb, k);
                    continue;
                }

                if ((dX < (vignetteWidth - fade)) | (dY < (vignetteWidth - fade)))
                {
                    outPixels[index] = (ta << 24) | (vignetteColor.getRed() << 16) | (vignetteColor.getGreen() << 8) | vignetteColor.getBlue();
                }
                else
                {
                    if ((dX < vignetteWidth)&(dY>vignetteWidth))
                    {
                        double k = 1 - (double)(dX - vignetteWidth + fade) / (double)fade;
                        outPixels[index] = superpositionColor(ta, tr, tg, tb, k);
                    }
                    else
                    {
                        if ((dY < vignetteWidth)&(dX > vignetteWidth))
                        {
                            double k = 1 - (double)(dY - vignetteWidth + fade) / (double)fade;
                            outPixels[index] = superpositionColor(ta, tr, tg, tb, k);
                        }
                        else
                        {
                            outPixels[index] = (ta << 24) | (tr << 16) | (tg << 8) | tb;
                        }
                    }
                }
            }
        }

        setRGB( dest, 0, 0, width, height, outPixels );
        return dest;
    }

    public int superpositionColor(int ta, int red, int green, int blue, double k) {
        red = (int)(vignetteColor.getRed() * k + red *(1.0-k));
        green = (int)(vignetteColor.getGreen() * k + green *(1.0-k));
        blue = (int)(vignetteColor.getBlue() * k + blue *(1.0-k));
        int color = (ta << 24) | (clamp(red) << 16) | (clamp(green) << 8) | clamp(blue);
        return color;
    }

    public int clamp(int value) {
        return value > 255 ? 255 :((value < 0) ? 0 : value);
    }

    public int getVignetteWidth() {
        return vignetteWidth;
    }

    public void setVignetteWidth(int vignetteWidth) {
        this.vignetteWidth = vignetteWidth;
    }

    public int getFade() {
        return fade;
    }

    public void setFade(int fade) {
        this.fade = fade;
    }

    public Color getVignetteColor() {
        return vignetteColor;
    }

    public void setVignetteColor(Color vignetteColor) {
        this.vignetteColor = vignetteColor;
    }

}