編輯:關於Android編程
android 圖片處理工具類封裝,包含保存圖片、 寫文件到SD卡,文件轉Bitmap、縮放,給圖片加倒影等強大功能
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; /** * 圖片操作工具包 * * @author liux (http://my.oschina.net/liux) * @version 1.0 * @created 2012-3-21 */ public class ImageUtils { public final static String SDCARD_MNT = "/mnt/sdcard"; public final static String SDCARD = "/sdcard"; /** 請求相冊 */ public static final int REQUEST_CODE_GETIMAGE_BYSDCARD = 0; /** 請求相機 */ public static final int REQUEST_CODE_GETIMAGE_BYCAMERA = 1; /** 請求裁剪 */ public static final int REQUEST_CODE_GETIMAGE_BYCROP = 2; /** * 寫圖片文件 在Android系統中,文件保存在 /data/data/PACKAGE_NAME/files 目錄下 * * @throws IOException */ public static void saveImage(Context context, String fileName, Bitmap bitmap) throws IOException { saveImage(context, fileName, bitmap, 100); } public static void saveImage(Context context, String fileName, Bitmap bitmap, int quality) throws IOException { if (bitmap == null || fileName == null || context == null) return; FileOutputStream fos = context.openFileOutput(fileName, Context.MODE_PRIVATE); ByteArrayOutputStream stream = new ByteArrayOutputStream(); bitmap.compress(CompressFormat.JPEG, quality, stream); byte[] bytes = stream.toByteArray(); fos.write(bytes); fos.close(); } /** * 寫圖片文件到SD卡 * * @throws IOException */ public static void saveImageToSD(Context ctx, String filePath, Bitmap bitmap, int quality) throws IOException { if (bitmap != null) { File file = new File(filePath.substring(0, filePath.lastIndexOf(File.separator))); if (!file.exists()) { file.mkdirs(); } BufferedOutputStream bos = new BufferedOutputStream( new FileOutputStream(filePath)); bitmap.compress(CompressFormat.JPEG, quality, bos); bos.flush(); bos.close(); if(ctx!=null){ scanPhoto(ctx, filePath); } } } /** * 讓Gallery上能馬上看到該圖片 */ private static void scanPhoto(Context ctx, String imgFileName) { Intent mediaScanIntent = new Intent( Intent.ACTION_MEDIA_SCANNER_SCAN_FILE); File file = new File(imgFileName); Uri contentUri = Uri.fromFile(file); mediaScanIntent.setData(contentUri); ctx.sendBroadcast(mediaScanIntent); } /** * 獲取bitmap * * @param context * @param fileName * @return */ public static Bitmap 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) { } } return bitmap; } /** * 獲取bitmap * * @param filePath * @return */ public static Bitmap getBitmapByPath(String filePath) { return getBitmapByPath(filePath, null); } public static Bitmap getBitmapByPath(String filePath, BitmapFactory.Options opts) { FileInputStream fis = null; Bitmap bitmap = null; try { File file = new File(filePath); fis = new FileInputStream(file); bitmap = BitmapFactory.decodeStream(fis, null, opts); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (OutOfMemoryError e) { e.printStackTrace(); } finally { try { fis.close(); } catch (Exception e) { } } return bitmap; } /** * 獲取bitmap * * @param file * @return */ public static Bitmap getBitmapByFile(File file) { FileInputStream fis = null; Bitmap bitmap = null; try { fis = new FileInputStream(file); bitmap = BitmapFactory.decodeStream(fis); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (OutOfMemoryError e) { e.printStackTrace(); } finally { try { fis.close(); } catch (Exception e) { } } return bitmap; } /** * 使用當前時間戳拼接一個唯一的文件名 * * @param format * @return */ public static String getTempFileName() { SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd_HH-mm-ss_SS"); String fileName = format.format(new Timestamp(System .currentTimeMillis())); return fileName; } /** * 獲取照相機使用的目錄 * * @return */ public static String getCamerPath() { return Environment.getExternalStorageDirectory() + File.separator + "FounderNews" + File.separator; } /** * 判斷當前Url是否標准的content://樣式,如果不是,則返回絕對路徑 * * @param uri * @return */ public static String 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()); } else if (mUriString.startsWith(pre2)) { filePath = Environment.getExternalStorageDirectory().getPath() + File.separator + mUriString.substring(pre2.length()); } return filePath; } /** * 通過uri獲取文件的絕對路徑 * * @param uri * @return */ public static String 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) { int column_index = cursor .getColumnIndexOrThrow(MediaStore.Images.Media.DATA); if (cursor.getCount() > 0 && cursor.moveToFirst()) { imagePath = cursor.getString(column_index); } } return imagePath; } /** * 獲取圖片縮略圖 只有Android2.1以上版本支持 * * @param imgName * @param kind * MediaStore.Images.Thumbnails.MICRO_KIND * @return */ public static Bitmap loadImgThumbnail(Activity context, String imgName, int kind) { 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 = new BitmapFactory.Options(); options.inSampleSize = 1; bitmap = MethodsCompat.getThumbnail(crThumb, cursor.getInt(0), kind, options); } return bitmap; } public static Bitmap loadImgThumbnail(String filePath, int w, int h) { Bitmap bitmap = getBitmapByPath(filePath); return zoomBitmap(bitmap, w, h); } /** * 獲取SD卡中最新圖片路徑 * * @return */ public static String 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; } } return latestImage; } /** * 計算縮放圖片的寬高 * * @param img_size * @param square_size * @return */ public static int[] scaleImageSize(int[] img_size, int square_size) { if (img_size[0] <= square_size && img_size[1] <= square_size) return img_size; double ratio = square_size / (double) Math.max(img_size[0], img_size[1]); return new int[] { (int) (img_size[0] * ratio), (int) (img_size[1] * ratio) }; } /** * 創建縮略圖 * * @param context * @param largeImagePath * 原始大圖路徑 * @param thumbfilePath * 輸出縮略圖路徑 * @param square_size * 輸出圖片寬度 * @param quality * 輸出圖片質量 * @throws IOException */ public static void createImageThumbnail(Context context, String largeImagePath, String thumbfilePath, int square_size, int quality) throws IOException { BitmapFactory.Options opts = new BitmapFactory.Options(); opts.inSampleSize = 1; // 原始圖片bitmap Bitmap cur_bitmap = getBitmapByPath(largeImagePath, opts); if (cur_bitmap == null) return; // 原始圖片的高寬 int[] cur_img_size = new int[] { cur_bitmap.getWidth(), cur_bitmap.getHeight() }; // 計算原始圖片縮放後的寬高 int[] new_img_size = scaleImageSize(cur_img_size, square_size); // 生成縮放後的bitmap Bitmap thb_bitmap = zoomBitmap(cur_bitmap, new_img_size[0], new_img_size[1]); // 生成縮放後的圖片文件 saveImageToSD(null,thumbfilePath, thb_bitmap, quality); } /** * 放大縮小圖片 * * @param bitmap * @param w * @param h * @return */ public static Bitmap zoomBitmap(Bitmap bitmap, int w, int h) { Bitmap newbmp = null; if (bitmap != null) { int width = bitmap.getWidth(); int height = bitmap.getHeight(); Matrix matrix = new Matrix(); float scaleWidht = ((float) w / width); float scaleHeight = ((float) h / height); matrix.postScale(scaleWidht, scaleHeight); newbmp = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true); } return newbmp; } public static Bitmap scaleBitmap(Bitmap bitmap) { // 獲取這個圖片的寬和高 int width = bitmap.getWidth(); int height = bitmap.getHeight(); // 定義預轉換成的圖片的寬度和高度 int newWidth = 200; int newHeight = 200; // 計算縮放率,新尺寸除原始尺寸 float scaleWidth = ((float) newWidth) / width; float scaleHeight = ((float) newHeight) / height; // 創建操作圖片用的matrix對象 Matrix matrix = new Matrix(); // 縮放圖片動作 matrix.postScale(scaleWidth, scaleHeight); // 旋轉圖片 動作 // matrix.postRotate(45); // 創建新的圖片 Bitmap resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true); return resizedBitmap; } /** * (縮放)重繪圖片 * * @param context * Activity * @param bitmap * @return */ public static Bitmap reDrawBitMap(Activity context, Bitmap bitmap) { DisplayMetrics dm = new DisplayMetrics(); context.getWindowManager().getDefaultDisplay().getMetrics(dm); int rHeight = dm.heightPixels; int rWidth = 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); int height = bitmap.getHeight(); int width = bitmap.getWidth(); float zoomScale; /** 方式1 **/ // if(rWidth/rHeight>width/height){//以高為准 // zoomScale=((float) rHeight) / height; // }else{ // //if(rWidth/rHeight= height) {//以寬為准 // if(width >= rWidth) // zoomScale = ((float) rWidth) / width; // else // zoomScale = 1.0f; // }else {//以高為准 // 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; // 創建操作圖片用的matrix對象 Matrix matrix = new Matrix(); // 縮放圖片動作 matrix.postScale(zoomScale, zoomScale); Bitmap resizedBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true); return resizedBitmap; } /** * 將Drawable轉化為Bitmap * * @param drawable * @return */ public static Bitmap drawableToBitmap(Drawable drawable) { int width = drawable.getIntrinsicWidth(); int height = drawable.getIntrinsicHeight(); Bitmap bitmap = Bitmap.createBitmap(width, height, drawable .getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565); Canvas canvas = new Canvas(bitmap); drawable.setBounds(0, 0, width, height); drawable.draw(canvas); return bitmap; } /** * 獲得圓角圖片的方法 * * @param bitmap * @param roundPx * 一般設成14 * @return */ 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; } /** * 獲得帶倒影的圖片方法 * * @param bitmap * @return */ 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; } /** * 將bitmap轉化為drawable * * @param bitmap * @return */ public static Drawable bitmapToDrawable(Bitmap bitmap) { Drawable drawable = new BitmapDrawable(bitmap); return drawable; } /** * 獲取圖片類型 * * @param file * @return */ public static String getImageType(File file) { if (file == null || !file.exists()) { return null; } InputStream in = null; try { in = new FileInputStream(file); String type = getImageType(in); return type; } catch (IOException e) { return null; } finally { try { if (in != null) { in.close(); } } catch (IOException e) { } } } /** * 獲取圖片的類型信息 * * @param in * @return * @see #getImageType(byte[]) */ public static String getImageType(InputStream in) { if (in == null) { return null; } try { byte[] bytes = new byte[8]; in.read(bytes); return getImageType(bytes); } catch (IOException e) { return null; } } /** * 獲取圖片的類型信息 * * @param bytes * 2~8 byte at beginning of the image file * @return image mimetype or null if the file is not image */ public static String 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"; } return null; } private static boolean isJPEG(byte[] b) { if (b.length < 2) { return false; } return (b[0] == (byte) 0xFF) && (b[1] == (byte) 0xD8); } private static boolean isGIF(byte[] b) { if (b.length < 6) { return false; } return b[0] == 'G' && b[1] == 'I' && b[2] == 'F' && b[3] == '8' && (b[4] == '7' || b[4] == '9') && b[5] == 'a'; } private static boolean isPNG(byte[] b) { if (b.length < 8) { return false; } 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); } private static boolean isBMP(byte[] b) { if (b.length < 2) { return false; } return (b[0] == 0x42) && (b[1] == 0x4d); } }
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