- 示例图
示例图片.jpg
如图，将上述图片处理成各种样式
- 将彩色图片转化为灰图
灰图.jpg
/**
* 将彩色图转换为灰度图
* @param img 位图
* @return 返回转换好的位图
*/
public Bitmap convertGreyImg(Bitmap img) {
int width = img.getWidth(); //获取位图的宽
int height = img.getHeight(); //获取位图的高
int []pixels = new int[width * height]; //通过位图的大小创建像素点数组
img.getPixels(pixels, 0, width, 0, 0, width, height);
int alpha = 0xFF << 24;
for(int i = 0; i < height; i++) {
for(int j = 0; j < width; j++) {
int grey = pixels[width * i + j];
int red = ((grey & 0x00FF0000 ) >> 16);
int green = ((grey & 0x0000FF00) >> 8);
int blue = (grey & 0x000000FF);
grey = (int)((float) red * 0.3 + (float)green * 0.59 + (float)blue * 0.11);
grey = alpha | (grey << 16) | (grey << 8) | grey;
pixels[width * i + j] = grey;
}
}
Bitmap result = Bitmap.createBitmap(width, height, Config.RGB_565);
result.setPixels(pixels, 0, width, 0, 0, width, height);
return result;
}
- 将图片转成圆角图
圆角图.jpg
public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, float roundPx) {
Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
bitmap.getHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final int color = 0xff424242;
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
final RectF rectF = new RectF(rect);
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint);
return output;
}
- 图片添加倒影效果
倒影.jpg
/**
* 获得带倒影的图片方法
*/
public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap) {
final int reflectionGap = 4;
int width = bitmap.getWidth();
int height = bitmap.getHeight();
Matrix matrix = new Matrix();
matrix.preScale(1, -1);
Bitmap reflectionImage = Bitmap.createBitmap(bitmap, 0, height / 2,
width, height / 2, matrix, false);
Bitmap bitmapWithReflection = Bitmap.createBitmap(width,
(height + height / 2), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmapWithReflection);
canvas.drawBitmap(bitmap, 0, 0, null);
Paint deafalutPaint = new Paint();
canvas.drawRect(0, height, width, height + reflectionGap, deafalutPaint);
canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null);
Paint paint = new Paint();
LinearGradient shader = new LinearGradient(0, bitmap.getHeight(), 0,
bitmapWithReflection.getHeight() + reflectionGap, 0x70ffffff,
0x00ffffff, TileMode.CLAMP);
paint.setShader(shader);
// Set the Transfer mode to be porter duff and destination in
paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
// Draw a rectangle using the paint with our linear gradient
canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()
+ reflectionGap, paint);
return bitmapWithReflection;
}
- 添加水印
右下角水印.jpg
/**
* create the bitmap from a byte array 生成水印图片
*
* @param src
* 要添加水印的图片
* @param 水印
* @return 添加了水印的图片
*/
private Bitmap createBitmap(Bitmap src, Bitmap watermark) {
String tag = "createBitmap";
Log.d(tag, "create a new bitmap");
if (src == null) {
return null;
}
int w = src.getWidth();
int h = src.getHeight();
int ww = watermark.getWidth();
int wh = watermark.getHeight();
// create the new blank bitmap
Bitmap newb = Bitmap.createBitmap(w, h, Config.ARGB_8888);// 创建一个新的和SRC长度宽度一样的位图
Canvas cv = new Canvas(newb);
// draw src into
cv.drawBitmap(src, 0, 0, null);// 在 0，0坐标开始画入src
// draw watermark into
cv.drawBitmap(watermark, w - ww + 5, h - wh + 5, null);// 在src的右下角画入水印
// save all clip
cv.save(Canvas.ALL_SAVE_FLAG);// 保存
// store
cv.restore();// 存储
return newb;
}
- View转成Bitmap
/**
* 把一个View的对象转换成bitmap
*/
static Bitmap getViewBitmap(View v) {
v.clearFocus();
v.setPressed(false);
// 能画缓存就返回false
boolean willNotCache = v.willNotCacheDrawing();
v.setWillNotCacheDrawing(false);
int color = v.getDrawingCacheBackgroundColor();
v.setDrawingCacheBackgroundColor(0);
if (color != 0) {
v.destroyDrawingCache();
}
v.buildDrawingCache();
Bitmap cacheBitmap = v.getDrawingCache();
if (cacheBitmap == null) {
Log.e(TAG, "failed getViewBitmap(" + v + ")",
new RuntimeException());
return null;
}
Bitmap bitmap = Bitmap.createBitmap(cacheBitmap);
// Restore the view
v.destroyDrawingCache();
v.setWillNotCacheDrawing(willNotCache);
v.setDrawingCacheBackgroundColor(color);
return bitmap;
}
相关链接：
图片处理（入门）
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