Android中图片的处理（放大缩小，去色，转换格式，增加水印等）
原文地址：http://menxu.lofter.com/post/164b9d_3ebf79
package com.teamkn.base.utils;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Paint;
import android.graphics.PorterDuff.Mode;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
/**
* 处理图片的工具类.
*/
public class ImageTools {
public static final int LEFT = 0;
public static final int RIGHT = 1;
public static final int TOP = 3;
public static final int BOTTOM = 4;
/** */
/**
* 图片去色,返回灰度图片
*
* @param bmpOriginal
* 传入的图片
* @return 去色后的图片
*/
public static Bitmap toGrayscale(Bitmap bmpOriginal) {
int width, height;
height = bmpOriginal.getHeight();
width = bmpOriginal.getWidth();
Bitmap bmpGrayscale = Bitmap.createBitmap(width, height,
Bitmap.Config.RGB_565);
Canvas c = new Canvas(bmpGrayscale);
Paint paint = new Paint();
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);
ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
paint.setColorFilter(f);
c.drawBitmap(bmpOriginal, 0, 0, paint);
return bmpGrayscale;
}
/** */
/**
* 去色同时加圆角
*
* @param bmpOriginal
* 原图
* @param pixels
* 圆角弧度
* @return 修改后的图片
*/
public static Bitmap toGrayscale(Bitmap bmpOriginal, int pixels) {
return toRoundCorner(toGrayscale(bmpOriginal), pixels);
}
/** */
/**
* 把图片变成圆角
*
* @param bitmap
* 需要修改的图片
* @param pixels
* 圆角的弧度
* @return 圆角图片
*/
public static Bitmap toRoundCorner(Bitmap bitmap, int pixels) {
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);
final float roundPx = pixels;
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;
}
/** */
/**
* 使圆角功能支持BitampDrawable
*
* @param bitmapDrawable
* @param pixels
* @return
*/
public static BitmapDrawable toRoundCorner(BitmapDrawable bitmapDrawable,
int pixels) {
Bitmap bitmap = bitmapDrawable.getBitmap();
bitmapDrawable = new BitmapDrawable(toRoundCorner(bitmap, pixels));
return bitmapDrawable;
}
/**
* 读取路径中的图片，然后将其转化为缩放后的bitmap
*
* @param path
*/
public static void saveBefore(String path) {
BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
// 获取这个图片的宽和高
Bitmap bitmap = BitmapFactory.decodeFile(path, options); // 此时返回bm为空
options.inJustDecodeBounds = false;
// 计算缩放比
int be = (int) (options.outHeight / (float) 200);
if (be <= 0)
be = 1;
options.inSampleSize = 2; // 图片长宽各缩小二分之一
// 重新读入图片，注意这次要把options.inJustDecodeBounds 设为 false哦
bitmap = BitmapFactory.decodeFile(path, options);
int w = bitmap.getWidth();
int h = bitmap.getHeight();
System.out.println(w + " " + h);
// savePNG_After(bitmap,path);
saveJPGE_After(bitmap, path);
}
/**
* 保存图片为PNG
*
* @param bitmap
* @param name
*/
public static void savePNG_After(Bitmap bitmap, String name) {
File file = new File(name);
try {
FileOutputStream out = new FileOutputStream(file);
if (bitmap.compress(Bitmap.CompressFormat.PNG, 100, out)) {
out.flush();
out.close();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 保存图片为JPEG
*
* @param bitmap
* @param path
*/
public static void saveJPGE_After(Bitmap bitmap, String path) {
File file = new File(path);
try {
FileOutputStream out = new FileOutputStream(file);
if (bitmap.compress(Bitmap.CompressFormat.JPEG, 100, out)) {
out.flush();
out.close();
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 水印
*
* @param bitmap
* @return
*/
public static Bitmap createBitmapForWatermark(Bitmap src, Bitmap watermark) {
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;
}
/**
* 图片合成
*
* @return
*/
public static Bitmap potoMix(int direction, Bitmap... bitmaps) {
if (bitmaps.length <= 0) {
return null;
}
if (bitmaps.length == 1) {
return bitmaps[0];
}
Bitmap newBitmap = bitmaps[0];
// newBitmap = createBitmapForFotoMix(bitmaps[0],bitmaps[1],direction);
for (int i = 1; i < bitmaps.length; i++) {
newBitmap = createBitmapForFotoMix(newBitmap, bitmaps[i], direction);
}
return newBitmap;
}
private static Bitmap createBitmapForFotoMix(Bitmap first, Bitmap second,
int direction) {
if (first == null) {
return null;
}
if (second == null) {
return first;
}
int fw = first.getWidth();
int fh = first.getHeight();
int sw = second.getWidth();
int sh = second.getHeight();
Bitmap newBitmap = null;
if (direction == LEFT) {
newBitmap = Bitmap.createBitmap(fw + sw, fh > sh ? fh : sh,
Config.ARGB_8888);
Canvas canvas = new Canvas(newBitmap);
canvas.drawBitmap(first, sw, 0, null);
canvas.drawBitmap(second, 0, 0, null);
} else if (direction == RIGHT) {
newBitmap = Bitmap.createBitmap(fw + sw, fh > sh ? fh : sh,
Config.ARGB_8888);
Canvas canvas = new Canvas(newBitmap);
canvas.drawBitmap(first, 0, 0, null);
canvas.drawBitmap(second, fw, 0, null);
} else if (direction == TOP) {
newBitmap = Bitmap.createBitmap(sw > fw ? sw : fw, fh + sh,
Config.ARGB_8888);
Canvas canvas = new Canvas(newBitmap);
canvas.drawBitmap(first, 0, sh, null);
canvas.drawBitmap(second, 0, 0, null);
} else if (direction == BOTTOM) {
newBitmap = Bitmap.createBitmap(sw > fw ? sw : fw, fh + sh,
Config.ARGB_8888);
Canvas canvas = new Canvas(newBitmap);
canvas.drawBitmap(first, 0, 0, null);
canvas.drawBitmap(second, 0, fh, null);
}
return newBitmap;
}
/**
* 将Bitmap转换成指定大小
*
* @param bitmap
* @param width
* @param height
* @return
*/
public static Bitmap createBitmapBySize(Bitmap bitmap, int width, int height) {
return Bitmap.createScaledBitmap(bitmap, width, height, true);
}
/**
* Drawable 转 Bitmap
*
* @param drawable
* @return
*/
public static Bitmap drawableToBitmapByBD(Drawable drawable) {
BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
return bitmapDrawable.getBitmap();
}
/**
* Bitmap 转 Drawable
*
* @param bitmap
* @return
*/
public static Drawable bitmapToDrawableByBD(Bitmap bitmap) {
Drawable drawable = new BitmapDrawable(bitmap);
return drawable;
}
/**
* 把一个文件转化为字节
*
* @param file
* @return byte[]
* @throws Exception
*/
public static byte[] getByte(File file) throws Exception {
byte[] bytes = null;
if (file != null) {
InputStream is = new FileInputStream(file);
int length = (int) file.length();
if (length > Integer.MAX_VALUE) // 当文件的长度超过了int的最大值
{
System.out.println("this file is max ");
return null;
}
bytes = new byte[length];
int offset = 0;
int numRead = 0;
while (offset < bytes.length
&& (numRead = is.read(bytes, offset, bytes.length - offset)) >= 0) {
offset += numRead;
}
// 如果得到的字节长度和file实际的长度不一致就可能出错了
if (offset < bytes.length) {
System.out.println("file length is error");
return null;
}
is.close();
}
return bytes;
}
/**
* byte[] 转 bitmap
*
* @param b
* @return
*/
public static Bitmap bytesToBimap(byte[] b) {
if (b.length != 0) {
return BitmapFactory.decodeByteArray(b, 0, b.length);
} else {
return null;
}
}
/**
* bitmap 转 byte[]
*
* @param bm
* @return
*/
public static byte[] bitmapToBytes(Bitmap bm) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
return baos.toByteArray();
}
}