图像滤镜艺术----Brannan滤镜

    作为第一篇文章，本人将介绍Instagram中Brannan 滤镜的实现过程，当然，是自己的模拟而已，结果差异敬请谅解。

    先看下效果图：

1 PS实现步骤：

1.1 打开测试图像，复制图层，命名为图层a；

1.2 对图层a进行去色操作，然后，打开色阶-绿色-调整如下：

1.3对当前图层a选择图层混合模式-滤色；

1.4新建图层b，填充颜色RGB(36,1, 34)，选择图层混合模式-柔光，不透明度60%：

1.5新建图层c，填充颜色RGB(253,253,241)，选择图层混合模式-正片叠底：

1.6合并所有图层，即可得到相应的效果图了；

2，程序实现：

<span style="font-size:14px;">public static Bitmap DoGrayEffect(Bitmap srcBitmap, int pxMode)
{
    Bitmap src = new Bitmap(srcBitmap);
    int w = src.Width;
    int h = src.Height;
    PixelFormat format = (pxMode == 0 ? PixelFormat.Format24bppRgb : PixelFormat.Format32bppArgb);
    BitmapData srcData = src.LockBits(new Rectangle(0, 0, w, h), ImageLockMode.ReadWrite, format);
    Desaturate((byte*)srcData.Scan0, w, h, srcData.Stride, pxMode);
    src.UnlockBits(srcData);
    return src;
}</span>

<span style="font-size:14px;"> //色阶调整
public static Bitmap DoLevelAdjust(Bitmap srcBitmap, int DestChannel, int InputLeftLimit, int InputMiddle, int InputRightLimit, int OutputLeftLimit, int OutputRightLimit, int pxMode)
{
    Bitmap src = new Bitmap(srcBitmap);
    int w = src.Width;
    int h = src.Height;
    PixelFormat format = (pxMode == 0 ? PixelFormat.Format24bppRgb : PixelFormat.Format32bppArgb);
    BitmapData srcData = src.LockBits(new Rectangle(0, 0, w, h), ImageLockMode.ReadWrite, format);
    LevelAdjust((byte*)srcData.Scan0, w, h, srcData.Stride, DestChannel, InputLeftLimit, InputMiddle, InputRightLimit, OutputLeftLimit, OutputRightLimit, pxMode);
    src.UnlockBits(srcData);
    return src;
}</span>

<span style="font-size:14px;">//图层混合模式
        public static Bitmap DoEffect(Bitmap srcBitmap, Bitmap mxBitmap, int pxMode, int effectMode)
        {
            Bitmap src = new Bitmap(srcBitmap);
            Bitmap mx = new Bitmap(mxBitmap);
            int w = src.Width;
            int h = src.Height;
            PixelFormat format = (pxMode == 0 ? PixelFormat.Format24bppRgb : PixelFormat.Format32bppArgb);
            BitmapData srcData = src.LockBits(new Rectangle(0, 0, w, h), ImageLockMode.ReadWrite, format);
            BitmapData mxData = mx.LockBits(new Rectangle(0, 0, w, h), ImageLockMode.ReadWrite, format);
            DoSpecialEffect((byte*)srcData.Scan0, (byte*)mxData.Scan0, w, h, srcData.Stride, pxMode, effectMode);
            src.UnlockBits(srcData);
            mx.UnlockBits(mxData);
            return src;
        }
        //单色图层混合模式
        public static Bitmap DoSingleColorEffect(Bitmap srcBitmap, int r, int g, int b, int pxMode, int effectMode)
        {
            Bitmap src = new Bitmap(srcBitmap);
            int w = src.Width;
            int h = src.Height;
            PixelFormat format = (pxMode == 0 ? PixelFormat.Format24bppRgb : PixelFormat.Format32bppArgb);
            BitmapData srcData = src.LockBits(new Rectangle(0, 0, w, h), ImageLockMode.ReadWrite, format);
            byte* p = (byte*)srcData.Scan0;
            int seg = (pxMode == 0 ? 3 : 4);
            for (int y = 0; y < h; y++)
            {
                for (int x = 0; x < w; x++)
                {
                    DoPixelEffect(p, r, g, b, effectMode);
                    p += seg;
                }
                p += srcData.Stride - w * seg;
            }
            src.UnlockBits(srcData);
            return src;
        }</span>

<span style="font-size:14px;">        //Brannan 滤镜
        public static Bitmap BrannanFilter(Bitmap srcBitmap, int pxMode)
        {
            Bitmap temp = DoGrayEffect(srcBitmap, 0);//去色
            Bitmap leBmp = DoLevelAdjust(temp, 2, 0, 128, 232, 0, 250, 0);//绿色色阶调整
            Bitmap filterBmp = DoEffect(srcBitmap, leBmp, 0, (int)EffectMode.MODE_FILTERCOLOR);//滤色
            temp = DoSingleColorEffect(filterBmp, 22, 1, 20, 0, (int)EffectMode.MODE_SMOOTHLIGHT);//柔化
            temp = DoSingleColorEffect(temp, 253, 253, 241, 0, (int)EffectMode.MODE_MULTIPLY);//正片叠底
            return temp;
        }</span>

PSD文件及C代码DEMO免费下载链接：点击打开链接

 

最后，分享一个专业的图像处理网站（微像素），里面有很多源代码下载：

http://www.zealpixel.com/portal.php