編輯:關於Android編程
1、Drawable → Bitmap
public static Bitmap drawableToBitmap(Drawable drawable) { Bitmap bitmap = Bitmap .createBitmap( drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565); Canvas canvas = new Canvas(bitmap); // canvas.setBitmap(bitmap); drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight()); drawable.draw(canvas); return bitmap; }
Resources res=getResources(); Bitmap bmp=BitmapFactory.decodeResource(res, R.drawable.pic);3、Bitmap → byte[]
private byte[] Bitmap2Bytes(Bitmap bm){ ByteArrayOutputStream baos = new ByteArrayOutputStream(); bm.compress(Bitmap.CompressFormat.PNG, 100, baos); return baos.toByteArray(); }
private Bitmap Bytes2Bimap(byte[] b){ if(b.length!=0){ return BitmapFactory.decodeByteArray(b, 0, b.length); } else { return null; } }5、保存bitmap
static boolean saveBitmap2file(Bitmap bmp,String filename){ CompressFormat format= Bitmap.CompressFormat.JPEG; int quality = 100; OutputStream stream = null; try { stream = new FileOutputStream("/sdcard/" + filename); } catch (FileNotFoundException e) { // TODO Auto-generated catch block Generated by Foxit PDF Creator © Foxit Software http://www.foxitsoftware.com For evaluation only. e.printStackTrace(); } return bmp.compress(format, quality, stream); }
// 圖片源 Bitmap bm = BitmapFactory.decodeStream(getResources() .openRawResource(R.drawable.dog)); // 獲得圖片的寬高 int width = bm.getWidth(); int height = bm.getHeight(); // 設置想要的大小 int newWidth = 320; int newHeight = 480; // 計算縮放比例 float scaleWidth = ((float) newWidth) / width; float scaleHeight = ((float) newHeight) / height; // 取得想要縮放的matrix參數 Matrix matrix = new Matrix(); matrix.postScale(scaleWidth, scaleHeight); // 得到新的圖片 Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix, true); // 放在畫布上 canvas.drawBitmap(newbm, 0, 0, paint);
7:File圖片轉Bitmap
Bitmap bt = BitmapFactory.decodeFile("/sdcard/myImage/" + "head.jpg");//圖片地址
public Bitmap drawableToBitamp(int drawableResource) { //可以取raw裡面的資源 BitmapFactory.Options opt = new BitmapFactory.Options(); opt.inPreferredConfig = Bitmap.Config.RGB_565; opt.inPurgeable = true; opt.inInputShareable = true; InputStream is = this.getResources().openRawResource(drawableResource); BitmapFactory.decodeStream(is, null, opt); return BitmapFactory.decodeStream(is, null, opt); }
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