) Bitmap usage Summary

(Conversion) bitmap usage Summary

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Bitmap usage Summary

1. drawable → bitmap

Public static bitmap drawabletobitmap (drawable ){

Bitmap bitmap = bitmap

. Createbitmap (

Drawable. getintrinsicwidth (),

Drawable. getintrinsicheight (),

Drawable. getopacity ()! = Pixelformat. opaque? Bitmap. config. argb_8888

: Bitmap. config. rgb_565 );

Canvas canvas = newcanvas (Bitmap );

// Canvas. setbitmap (Bitmap );

Drawable. setbounds (0, 0, drawable. getintrinsicwidth (),

Drawable. getintrinsicheight ());

Drawable. Draw (canvas );

Return bitmap;

}

2. Obtain bitmap from a resource

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 ();

}

4. byte [] → bitmap

Private bitmap bytes2bimap (byte [] B ){

If (B. length! = 0 ){

Return bitmapfactory. decodebytearray (B, 0, B. Length );

}

Else {

Return NULL;

}

}

5. Save 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

E. printstacktrace ();

}

Return BMP. Compress (format, quality, stream );

}

6. Scale the image as needed

// Image Source

Bitmap Bm = bitmapfactory. decodestream (getresources ()

. Openrawresource (R. drawable. Dog ));

// Obtain the image width and height

Int width = BM. getwidth ();

Int Height = BM. getheight ();

// Set the desired size

Int newwidth = 320;

Int newheight = 480;

// Calculate the scaling ratio

Float scalewidth = (float) newwidth)/width;

Float scaleheight = (float) newheight)/height;

// Obtain the matrix parameter to be scaled.

Matrix matrix = new matrix ();

Matrix. postscale (scalewidth, scaleheight );

// Get a new image

Bitmap newbm = bitmap. createbitmap (BM, 0, 0, width, height, matrix,

True );

// Place it on the canvas

Canvas. drawbitmap (newbm, 0, 0, paint );

7. Usage of Bitmap

Bitmapfactory. Options option = new bitmapfactory. Options ();

Option. insamplesize = 2; // set the image to 1/2 in width to prevent memory overflow.

Bitmap Bm = bitmapfactory. decodefile ("", option); // file stream

URL url = new URL ("");

Inputstream is = URL. openstream ();

Bitmap Bm = bitmapfactory. decodestream (is );

 

// Zoom in and out the image

Public static bitmap zoombitmap (Bitmap bitmap, int W, int h ){

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 );

Bitmap newbmp = bitmap. createbitmap (bitmap, 0, 0, width, height, matrix,

True );

Return newbmp;

}

// Converts drawable to bitmap

Public static bitmap drawabletobitmap (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;

}

// Obtain the rounded corner Image

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 = 0xff0000242;

Final paint = new paint ();

Final rect = new rect (0, 0, bitmap. getwidth (), bitmap. getheight ());

Final 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 porterduxfermode (mode. src_in ));

Canvas. drawbitmap (bitmap, rect, rect, paint );

Return output;

}

// Method for obtaining images with reflections

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 ();

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A http://www.foxitsoftware.com for evaluation only.

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 porterduxfermode (mode. dst_in ));

// Draw a rectangle using the paint with our linear gradient

Canvas. drawrect (0, height, width, bitmapwithreflection. getheight ()

+ Reflectiongap, paint );

Return bitmapwithreflection;

}

}