Android image processing (3) Emboss effect

This article will talk about the effect of image effects processing relief. As before, the pixel is processed, and the algorithm is universal.

Algorithm principle: Subtract the RGB value of the current pixel by the RGB value of the previous pixel, and add 127 as the RGB value of the current pixel point.

Cases:

Abc

The relief effect of the B point is as follows:

B.R = C.R-B.R + 127;

B.G = c.g-b.g + 127;

B.B = c.b-b.b + 127;

Note the RGB values are between 0~255.

：

Original

[Java]View PlainCopy

2. Package com.color;
6. Import Android.content.Context;
8. Import Android.graphics.Bitmap;
10. Import Android.graphics.BitmapFactory;
12. Import Android.graphics.Canvas;
14. Import Android.graphics.Color;
16. Import Android.graphics.Paint;
18. Import Android.util.AttributeSet;
20. Import Android.widget.ImageView;
24. Public class Colorview extends ImageView {
28. private Paint mypaint = null;
30. private Bitmap Bitmap = null;
32. private int width,height;
34. private int[] oldpixels;
36. private int[] newpixels;
38. private int color,color2;
40. private int pixelsr,pixelsg,pixelsb,pixelsa,pixelsr2,pixelsg2,pixelsb2;
44. Public Colorview (context context, AttributeSet attrs)
46. {
48. Super (context, attrs);
50. Bitmap = Bitmapfactory.decoderesource (Context.getresources (), R.DRAWABLE.WW);
52. width = Bitmap.getwidth ();
54. Height = bitmap.getheight ();
56. Oldpixels = new int[width*height];
58. Newpixels = new int[width*height];
60. Invalidate ();
62. }
64. @Override
66. protected void OnDraw (canvas canvas) {
68. Super.ondraw (canvas);
70. //Get pixels
72. Bitmap.getpixels (Oldpixels, 0, width, 0, 0, width, height);
76. For (int i = 1;i < height*width; i++) {
78. color = oldpixels[i-1];
80. //Previous pixel
82. PIXELSR = Color.Red (Color);
84. PIXELSG = Color.green (Color);
86. PIXELSB = Color.Blue (Color);
88. //Current pixel
90. Color2 = Oldpixels[i];
92. pixelsR2 = Color.Red (Color2);
94. pixelsG2 = Color.green (Color2);
96. pixelsB2 = Color.Blue (Color2);
100. PIXELSR = (PIXELSR-PIXELSR2 + 127);
102. PIXELSG = (PIXELSG-PIXELSG2 + 127);
104. PIXELSB = (PIXELSB-PIXELSB2 + 127);
106. //Both are less than or equal to 255
108. if (PIXELSR > 255) {
110. PIXELSR = 255;
112. }
116. if (pixelsg > 255) {
118. PIXELSG = 255;
120. }
124. if (pixelsb > 255) {
126. PIXELSB = 255;
128. }
132. Newpixels[i] = Color.argb (Pixelsa, PIXELSR, PIXELSG, PIXELSB);
136. }
138. Bitmap.setpixels (Newpixels, 0, width, 0, 0, width, height);
140. Canvas.drawbitmap (Bitmap,0,0,mypaint);
142. }
144. }

Android image processing (3) Emboss effect