Android 图片处理工具类封装2

来源：互联网发布：利用单片机制作恒流源编辑：程序博客网时间：2024/05/16 10:51
http://www.2cto.com/kf/201312/263638.html
Android 图片处理工具类封装2013-12-10     0 个评论   来源：Wiker Yong 的专栏   收藏  我要投稿
android 图片处理工具类封装，包含保存图片、 写文件到SD卡，文件转Bitmap、缩放，给图片加倒影等强大功能

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import java.io.BufferedOutputStream;
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 java.sql.Timestamp;
import java.text.SimpleDateFormat;
 
import android.app.Activity;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.LinearGradient;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.PorterDuff.Mode;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Shader.TileMode;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.DisplayMetrics;
 
/**
 * 图片操作工具包
 *
 * @author liux (http://my.oschina.net/liux)
 * @version 1.0
 * @created 2012-3-21
 */
public class ImageUtils {
 
    publicfinalstatic String SDCARD_MNT ="/mnt/sdcard";
    publicfinalstatic String SDCARD ="/sdcard";
 
    /** 请求相册 */
    publicstaticfinal int REQUEST_CODE_GETIMAGE_BYSDCARD = 0;
    /** 请求相机 */
    publicstaticfinal int REQUEST_CODE_GETIMAGE_BYCAMERA = 1;
    /** 请求裁剪 */
    publicstaticfinal int REQUEST_CODE_GETIMAGE_BYCROP = 2;
 
    /**
     * 写图片文件 在Android系统中，文件保存在 /data/data/PACKAGE_NAME/files 目录下
     *
     * @throws IOException
     */
    publicstaticvoid saveImage(Context context, String fileName, Bitmap bitmap)
            throwsIOException {
        saveImage(context, fileName, bitmap,100);
    }
 
    publicstaticvoid saveImage(Context context, String fileName,
            Bitmap bitmap,intquality) throwsIOException {
        if(bitmap ==null|| fileName ==null|| context ==null)
            return;
 
        FileOutputStream fos = context.openFileOutput(fileName,
                Context.MODE_PRIVATE);
        ByteArrayOutputStream stream =newByteArrayOutputStream();
        bitmap.compress(CompressFormat.JPEG, quality, stream);
        byte[] bytes = stream.toByteArray();
        fos.write(bytes);
        fos.close();
    }
 
    /**
     * 写图片文件到SD卡
     *
     * @throws IOException
     */
    publicstaticvoid saveImageToSD(Context ctx, String filePath,
            Bitmap bitmap,intquality) throwsIOException {
        if(bitmap !=null) {
            File file =newFile(filePath.substring(0,
                    filePath.lastIndexOf(File.separator)));
            if(!file.exists()) {
                file.mkdirs();
            }
            BufferedOutputStream bos =newBufferedOutputStream(
                    newFileOutputStream(filePath));
            bitmap.compress(CompressFormat.JPEG, quality, bos);
            bos.flush();
            bos.close();
            if(ctx!=null){
                scanPhoto(ctx, filePath);
            }
        }
    }
 
    /**
     * 让Gallery上能马上看到该图片
     */
    privatestaticvoid scanPhoto(Context ctx, String imgFileName) {
        Intent mediaScanIntent =newIntent(
                Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);
        File file =newFile(imgFileName);
        Uri contentUri = Uri.fromFile(file);
        mediaScanIntent.setData(contentUri);
        ctx.sendBroadcast(mediaScanIntent);
    }
 
    /**
     * 获取bitmap
     *
     * @param context
     * @param fileName
     * @return
     */
    publicstaticBitmap getBitmap(Context context, String fileName) {
        FileInputStream fis =null;
        Bitmap bitmap =null;
        try{
            fis = context.openFileInput(fileName);
            bitmap = BitmapFactory.decodeStream(fis);
        }catch(FileNotFoundException e) {
            e.printStackTrace();
        }catch(OutOfMemoryError e) {
            e.printStackTrace();
        }finally{
            try{
                fis.close();
            }catch(Exception e) {
            }
        }
        returnbitmap;
    }
 
    /**
     * 获取bitmap
     *
     * @param filePath
     * @return
     */
    publicstaticBitmap getBitmapByPath(String filePath) {
        returngetBitmapByPath(filePath,null);
    }
 
    publicstaticBitmap getBitmapByPath(String filePath,
            BitmapFactory.Options opts) {
        FileInputStream fis =null;
        Bitmap bitmap =null;
        try{
            File file =newFile(filePath);
            fis =newFileInputStream(file);
            bitmap = BitmapFactory.decodeStream(fis,null, opts);
        }catch(FileNotFoundException e) {
            e.printStackTrace();
        }catch(OutOfMemoryError e) {
            e.printStackTrace();
        }finally{
            try{
                fis.close();
            }catch(Exception e) {
            }
        }
        returnbitmap;
    }
 
    /**
     * 获取bitmap
     *
     * @param file
     * @return
     */
    publicstaticBitmap getBitmapByFile(File file) {
        FileInputStream fis =null;
        Bitmap bitmap =null;
        try{
            fis =newFileInputStream(file);
            bitmap = BitmapFactory.decodeStream(fis);
        }catch(FileNotFoundException e) {
            e.printStackTrace();
        }catch(OutOfMemoryError e) {
            e.printStackTrace();
        }finally{
            try{
                fis.close();
            }catch(Exception e) {
            }
        }
        returnbitmap;
    }
 
    /**
     * 使用当前时间戳拼接一个唯一的文件名
     *
     * @param format
     * @return
     */
    publicstaticString getTempFileName() {
        SimpleDateFormat format =newSimpleDateFormat("yyyy-MM-dd_HH-mm-ss_SS");
        String fileName = format.format(newTimestamp(System
                .currentTimeMillis()));
        returnfileName;
    }
 
    /**
     * 获取照相机使用的目录
     *
     * @return
     */
    publicstaticString getCamerPath() {
        returnEnvironment.getExternalStorageDirectory() + File.separator
                +"FounderNews"+ File.separator;
    }
 
    /**
     * 判断当前Url是否标准的content://样式，如果不是，则返回绝对路径
     *
     * @param uri
     * @return
     */
    publicstaticString getAbsolutePathFromNoStandardUri(Uri mUri) {
        String filePath =null;
 
        String mUriString = mUri.toString();
        mUriString = Uri.decode(mUriString);
 
        String pre1 ="file://"+ SDCARD + File.separator;
        String pre2 ="file://"+ SDCARD_MNT + File.separator;
 
        if(mUriString.startsWith(pre1)) {
            filePath = Environment.getExternalStorageDirectory().getPath()
                    + File.separator + mUriString.substring(pre1.length());
        }elseif(mUriString.startsWith(pre2)) {
            filePath = Environment.getExternalStorageDirectory().getPath()
                    + File.separator + mUriString.substring(pre2.length());
        }
        returnfilePath;
    }
 
    /**
     * 通过uri获取文件的绝对路径
     *
     * @param uri
     * @return
     */
    publicstaticString getAbsoluteImagePath(Activity context, Uri uri) {
        String imagePath ="";
        String[] proj = { MediaStore.Images.Media.DATA };
        Cursor cursor = context.managedQuery(uri, proj,// Which columns to
                                                        // return
                null,// WHERE clause; which rows to return (all rows)
                null,// WHERE clause selection arguments (none)
                null);// Order-by clause (ascending by name)
 
        if(cursor !=null) {
            intcolumn_index = cursor
                    .getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
            if(cursor.getCount() >0&& cursor.moveToFirst()) {
                imagePath = cursor.getString(column_index);
            }
        }
 
        returnimagePath;
    }
 
    /**
     * 获取图片缩略图 只有Android2.1以上版本支持
     *
     * @param imgName
     * @param kind
     *            MediaStore.Images.Thumbnails.MICRO_KIND
     * @return
     */
    publicstaticBitmap loadImgThumbnail(Activity context, String imgName,
            intkind) {
        Bitmap bitmap =null;
 
        String[] proj = { MediaStore.Images.Media._ID,
                MediaStore.Images.Media.DISPLAY_NAME };
 
        Cursor cursor = context.managedQuery(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI, proj,
                MediaStore.Images.Media.DISPLAY_NAME +"='"+ imgName +"'",
                null,null);
 
        if(cursor !=null&& cursor.getCount() >0&& cursor.moveToFirst()) {
            ContentResolver crThumb = context.getContentResolver();
            BitmapFactory.Options options =newBitmapFactory.Options();
            options.inSampleSize =1;
            bitmap = MethodsCompat.getThumbnail(crThumb, cursor.getInt(0),
                    kind, options);
        }
        returnbitmap;
    }
 
    publicstaticBitmap loadImgThumbnail(String filePath,intw, inth) {
        Bitmap bitmap = getBitmapByPath(filePath);
        returnzoomBitmap(bitmap, w, h);
    }
 
    /**
     * 获取SD卡中最新图片路径
     *
     * @return
     */
    publicstaticString getLatestImage(Activity context) {
        String latestImage =null;
        String[] items = { MediaStore.Images.Media._ID,
                MediaStore.Images.Media.DATA };
        Cursor cursor = context.managedQuery(
                MediaStore.Images.Media.EXTERNAL_CONTENT_URI, items,null,
                null, MediaStore.Images.Media._ID +" desc");
 
        if(cursor !=null&& cursor.getCount() >0) {
            cursor.moveToFirst();
            for(cursor.moveToFirst(); !cursor.isAfterLast(); cursor
                    .moveToNext()) {
                latestImage = cursor.getString(1);
                break;
            }
        }
 
        returnlatestImage;
    }
 
    /**
     * 计算缩放图片的宽高
     *
     * @param img_size
     * @param square_size
     * @return
     */
    publicstaticint[] scaleImageSize(int[] img_size,intsquare_size) {
        if(img_size[0] <= square_size && img_size[1] <= square_size)
            returnimg_size;
        doubleratio = square_size
                / (double) Math.max(img_size[0], img_size[1]);
        returnnewint[] { (int) (img_size[0] * ratio),
                (int) (img_size[1] * ratio) };
    }
 
    /**
     * 创建缩略图
     *
     * @param context
     * @param largeImagePath
     *            原始大图路径
     * @param thumbfilePath
     *            输出缩略图路径
     * @param square_size
     *            输出图片宽度
     * @param quality
     *            输出图片质量
     * @throws IOException
     */
    publicstaticvoid createImageThumbnail(Context context,
            String largeImagePath, String thumbfilePath,intsquare_size,
            intquality)throwsIOException {
        BitmapFactory.Options opts =newBitmapFactory.Options();
        opts.inSampleSize =1;
        // 原始图片bitmap
        Bitmap cur_bitmap = getBitmapByPath(largeImagePath, opts);
 
        if(cur_bitmap ==null)
            return;
 
        // 原始图片的高宽
        int[] cur_img_size =newint[] { cur_bitmap.getWidth(),
                cur_bitmap.getHeight() };
        // 计算原始图片缩放后的宽高
        int[] new_img_size = scaleImageSize(cur_img_size, square_size);
        // 生成缩放后的bitmap
        Bitmap thb_bitmap = zoomBitmap(cur_bitmap, new_img_size[0],
                new_img_size[1]);
        // 生成缩放后的图片文件
        saveImageToSD(null,thumbfilePath, thb_bitmap, quality);
    }
 
    /**
     * 放大缩小图片
     *
     * @param bitmap
     * @param w
     * @param h
     * @return
     */
    publicstaticBitmap zoomBitmap(Bitmap bitmap,intw, inth) {
        Bitmap newbmp =null;
        if(bitmap !=null) {
            intwidth = bitmap.getWidth();
            intheight = bitmap.getHeight();
            Matrix matrix =newMatrix();
            floatscaleWidht = ((float) w / width);
            floatscaleHeight = ((float) h / height);
            matrix.postScale(scaleWidht, scaleHeight);
            newbmp = Bitmap.createBitmap(bitmap,0,0, width, height, matrix,
                    true);
        }
        returnnewbmp;
    }
 
    publicstaticBitmap scaleBitmap(Bitmap bitmap) {
        // 获取这个图片的宽和高
        intwidth = bitmap.getWidth();
        intheight = bitmap.getHeight();
        // 定义预转换成的图片的宽度和高度
        intnewWidth =200;
        intnewHeight =200;
        // 计算缩放率，新尺寸除原始尺寸
        floatscaleWidth = ((float) newWidth) / width;
        floatscaleHeight = ((float) newHeight) / height;
        // 创建操作图片用的matrix对象
        Matrix matrix =newMatrix();
        // 缩放图片动作
        matrix.postScale(scaleWidth, scaleHeight);
        // 旋转图片 动作
        // matrix.postRotate(45);
        // 创建新的图片
        Bitmap resizedBitmap = Bitmap.createBitmap(bitmap,0,0, width, height,
                matrix,true);
        returnresizedBitmap;
    }
 
    /**
     * (缩放)重绘图片
     *
     * @param context
     *            Activity
     * @param bitmap
     * @return
     */
    publicstaticBitmap reDrawBitMap(Activity context, Bitmap bitmap) {
        DisplayMetrics dm =newDisplayMetrics();
        context.getWindowManager().getDefaultDisplay().getMetrics(dm);
        intrHeight = dm.heightPixels;
        intrWidth = dm.widthPixels;
        // float rHeight=dm.heightPixels/dm.density+0.5f;
        // float rWidth=dm.widthPixels/dm.density+0.5f;
        // int height=bitmap.getScaledHeight(dm);
        // int width = bitmap.getScaledWidth(dm);
        intheight = bitmap.getHeight();
        intwidth = bitmap.getWidth();
        floatzoomScale;
        /** 方式1 **/
        // if(rWidth/rHeight>width/height){//以高为准
        // zoomScale=((float) rHeight) / height;
        // }else{
        // //if(rWidth/rHeight<width height)="" 以宽为准="" zoomscale="((float)" rwidth)="" width;="" }="" **="" 方式2="" if(width*1.5="">= height) {//以宽为准
        // if(width >= rWidth)
        // zoomScale = ((float) rWidth) / width;
        // else
        // zoomScale = 1.0f;
        // }else {//以高为准
        // if(height >= rHeight)
        // zoomScale = ((float) rHeight) / height;
        // else
        // zoomScale = 1.0f;
        // }
        /** 方式3 **/
        if(width >= rWidth)
            zoomScale = ((float) rWidth) / width;
        else
            zoomScale =1.0f;
        // 创建操作图片用的matrix对象
        Matrix matrix =newMatrix();
        // 缩放图片动作
        matrix.postScale(zoomScale, zoomScale);
        Bitmap resizedBitmap = Bitmap.createBitmap(bitmap,0,0,
                bitmap.getWidth(), bitmap.getHeight(), matrix,true);
        returnresizedBitmap;
    }
 
    /**
     * 将Drawable转化为Bitmap
     *
     * @param drawable
     * @return
     */
    publicstaticBitmap drawableToBitmap(Drawable drawable) {
        intwidth = drawable.getIntrinsicWidth();
        intheight = drawable.getIntrinsicHeight();
        Bitmap bitmap = Bitmap.createBitmap(width, height, drawable
                .getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888
                : Bitmap.Config.RGB_565);
        Canvas canvas =newCanvas(bitmap);
        drawable.setBounds(0,0, width, height);
        drawable.draw(canvas);
        returnbitmap;
 
    }
 
    /**
     * 获得圆角图片的方法
     *
     * @param bitmap
     * @param roundPx
     *            一般设成14
     * @return
     */
    publicstaticBitmap getRoundedCornerBitmap(Bitmap bitmap,floatroundPx) {
 
        Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
                bitmap.getHeight(), Config.ARGB_8888);
        Canvas canvas =newCanvas(output);
 
        finalintcolor = 0xff424242;
        finalPaint paint =newPaint();
        finalRect rect =newRect(0,0, bitmap.getWidth(), bitmap.getHeight());
        finalRectF rectF =newRectF(rect);
 
        paint.setAntiAlias(true);
        canvas.drawARGB(0,0,0,0);
        paint.setColor(color);
        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
 
        paint.setXfermode(newPorterDuffXfermode(Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
 
        returnoutput;
    }
 
    /**
     * 获得带倒影的图片方法
     *
     * @param bitmap
     * @return
     */
    publicstaticBitmap createReflectionImageWithOrigin(Bitmap bitmap) {
        finalintreflectionGap = 4;
        intwidth = bitmap.getWidth();
        intheight = bitmap.getHeight();
 
        Matrix matrix =newMatrix();
        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 =newCanvas(bitmapWithReflection);
        canvas.drawBitmap(bitmap,0,0,null);
        Paint deafalutPaint =newPaint();
        canvas.drawRect(0, height, width, height + reflectionGap, deafalutPaint);
 
        canvas.drawBitmap(reflectionImage,0, height + reflectionGap,null);
 
        Paint paint =newPaint();
        LinearGradient shader =newLinearGradient(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(newPorterDuffXfermode(Mode.DST_IN));
        // Draw a rectangle using the paint with our linear gradient
        canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()
                + reflectionGap, paint);
 
        returnbitmapWithReflection;
    }
 
    /**
     * 将bitmap转化为drawable
     *
     * @param bitmap
     * @return
     */
    publicstaticDrawable bitmapToDrawable(Bitmap bitmap) {
        Drawable drawable =newBitmapDrawable(bitmap);
        returndrawable;
    }
 
    /**
     * 获取图片类型
     *
     * @param file
     * @return
     */
    publicstaticString getImageType(File file) {
        if(file ==null || !file.exists()) {
            returnnull;
        }
        InputStream in =null;
        try{
            in =newFileInputStream(file);
            String type = getImageType(in);
            returntype;
        }catch(IOException e) {
            returnnull;
        }finally{
            try{
                if(in !=null) {
                    in.close();
                }
            }catch(IOException e) {
            }
        }
    }
 
    /**
     * 获取图片的类型信息
     *
     * @param in
     * @return
     * @see #getImageType(byte[])
     */
    publicstaticString getImageType(InputStream in) {
        if(in ==null) {
            returnnull;
        }
        try{
            byte[] bytes =newbyte[8];
            in.read(bytes);
            returngetImageType(bytes);
        }catch(IOException e) {
            returnnull;
        }
    }
 
    /**
     * 获取图片的类型信息
     *
     * @param bytes
     *            2~8 byte at beginning of the image file
     * @return image mimetype or null if the file is not image
     */
    publicstaticString getImageType(byte[] bytes) {
        if(isJPEG(bytes)) {
            return"image/jpeg";
        }
        if(isGIF(bytes)) {
            return"image/gif";
        }
        if(isPNG(bytes)) {
            return"image/png";
        }
        if(isBMP(bytes)) {
            return"application/x-bmp";
        }
        returnnull;
    }
 
    privatestaticbooleanisJPEG(byte[] b) {
        if(b.length <2) {
            returnfalse;
        }
        return(b[0] == (byte)0xFF) && (b[1] == (byte)0xD8);
    }
 
    privatestaticbooleanisGIF(byte[] b) {
        if(b.length <6) {
            returnfalse;
        }
        returnb[0] =='G'&& b[1] =='I'&& b[2] =='F'&& b[3] =='8'
                && (b[4] =='7'|| b[4] =='9') && b[5] =='a';
    }
 
    privatestaticbooleanisPNG(byte[] b) {
        if(b.length <8) {
            returnfalse;
        }
        return(b[0] == (byte)137&& b[1] == (byte)80&& b[2] == (byte)78
                && b[3] == (byte)71&& b[4] == (byte)13&& b[5] == (byte)10
                && b[6] == (byte)26&& b[7] == (byte)10);
    }
 
    privatestaticbooleanisBMP(byte[] b) {
        if(b.length <2) {
            returnfalse;
        }
        return(b[0] ==0x42) && (b[1] ==0x4d);
    }

 /** 
     * 添加文字到图片，类似水印文字。 
     * @param gContext 
     * @param gResId 
     * @param gText 
     * @return 
     */  
    public static Bitmap drawTextToBitmap(Context gContext, int gResId, String gText) {  
        Resources resources = gContext.getResources();  
        float scale = resources.getDisplayMetrics().density;  
        Bitmap bitmap = BitmapFactory.decodeResource(resources, gResId);  
  
        android.graphics.Bitmap.Config bitmapConfig = bitmap.getConfig();  
        // set default bitmap config if none  
        if (bitmapConfig == null) {  
            bitmapConfig = android.graphics.Bitmap.Config.ARGB_8888;  
        }  
        // resource bitmaps are imutable,  
        // so we need to convert it to mutable one  
        bitmap = bitmap.copy(bitmapConfig, true);  
  
        Canvas canvas = new Canvas(bitmap);  
        // new antialised Paint  
        Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);  
        // text color - #3D3D3D  
        paint.setColor(Color.rgb(61,61,61));  
        // text size in pixels  
        paint.setTextSize((int) (14 * scale*5));  
        // text shadow  
        paint.setShadowLayer(1f, 0f, 1f, Color.WHITE);  
  
        // draw text to the Canvas center  
        Rect bounds = new Rect();  
        paint.getTextBounds(gText, 0, gText.length(), bounds);  
//      int x = (bitmap.getWidth() - bounds.width()) / 2;  
//      int y = (bitmap.getHeight() + bounds.height()) / 2;  
        //draw  text  to the bottom  
        int x = (bitmap.getWidth() - bounds.width())/10*9 ;  
        int y = (bitmap.getHeight() + bounds.height())/10*9;  
        canvas.drawText(gText, x , y, paint);  
  
        return bitmap;  
    }  

}
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