"Turn" VI, image overlay of Android image effect processing

This article will talk about the image overlay effect processed by picture effects. The same as the front face is the pixel processing, you can refer to the previous Android image processing series seven-picture graffiti, watermark-image overlay and Android image processing series six-to the picture to add a border (bottom)-image overlay two articles, This article is a little different from the previous one. The superposition principle is that the pixels of two pictures are superimposed by transparency, and no color filtering is done. Overlay images can be in JPG format, in front of the same, it is best to enlarge the assets directory. See below:

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Code:

/*** Picture Effect overlay *@paramBMP limits the size of the bitmap *@return     */    PrivateBitmap Overlay (Bitmap bmp) {LongStart =System.currenttimemillis (); intwidth =bmp.getwidth (); intHeight =bmp.getheight (); Bitmap Bitmap=bitmap.createbitmap (width, height, Bitmap.Config.RGB_565); //zoom in on a border pictureBitmap overlay =Bitmapfactory.decoderesource (Mcontext.getresources (), r.drawable.rainbow_overlay); intW =overlay.getwidth (); inth =overlay.getheight (); floatScaleX = width * 1F/W; floatScaleY = height * 1F/h; Matrix Matrix=NewMatrix ();                Matrix.postscale (ScaleX, ScaleY); Bitmap overlaycopy= Bitmap.createbitmap (overlay, 0, 0, W, h, Matrix,true); intPixcolor = 0; intLaycolor = 0; intPIXR = 0; intPIXG = 0; intPIXB = 0; intPixA = 0; intNEWR = 0; intNEWG = 0; intNewb = 0; intNewa = 0; intLayr = 0; intLAYG = 0; intLayb = 0; intLayA = 0; Final floatAlpha = 0.5F; int[] Srcpixels =New int[Width *height]; int[] Laypixels =New int[Width *height]; Bmp.getpixels (Srcpixels,0, Width, 0, 0, width, height); Overlaycopy.getpixels (Laypixels,0, Width, 0, 0, width, height); intpos = 0;  for(inti = 0; i < height; i++)        {             for(intk = 0; K < width; k++) {pos= i * width +K; Pixcolor=Srcpixels[pos]; Laycolor=Laypixels[pos]; PIXR=color.red (Pixcolor); Pixg=Color.green (Pixcolor); PIXB=Color.Blue (Pixcolor); PixA=Color.alpha (Pixcolor); Layr=color.red (Laycolor); LAYG=Color.green (Laycolor); Layb=Color.Blue (Laycolor); LayA=Color.alpha (Laycolor); NEWR= (int) (PIXR * alpha + Layr * (1-Alpha)); NEWG= (int) (PIXG * alpha + LAYG * (1-Alpha)); Newb= (int) (PIXB * alpha + Layb * (1-Alpha)); LayA= (int) (PixA * alpha + LayA * (1-Alpha)); NEWR= Math.min (255, Math.max (0, NEWR)); NEWG= Math.min (255, Math.max (0, NEWG)); Newb= Math.min (255, Math.max (0, newb)); Newa= Math.min (255, Math.max (0, LayA)); Srcpixels[pos]=Color.argb (Newa, NEWR, NEWG, newb); }} bitmap.setpixels (Srcpixels,0, Width, 0, 0, width, height); LongEnd =System.currenttimemillis (); LOG.D ("May", "Overlayameliorate used time=" + (End-start)); returnbitmap; }

Overlay picture of the border is better, but also to control the size of the superimposed picture. The value of alpha variable can be modified according to demand, the proposal or more than 0.5 is better, otherwise the original will not see clearly.