Android中Bitmap对象和字节流之间的相互转换（转）

android 将图片内容解析成字节数组；将字节数组转换为ImageView可调用的Bitmap对象；图片缩放；把字节数组保存为一个文件；把Bitmap转Byte

 import java.io.BufferedOutputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;  

 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.graphics.Matrix;  

 public class ImageDispose {  

     /**
      * @param 将图片内容解析成字节数组
      * @param inStream
      * @return byte[]
      * @throws Exception
      */
     public static byte[] readStream(InputStream inStream) throws Exception {
         byte[] buffer = new byte[1024];
         int len = -1;
         ByteArrayOutputStream outStream = new ByteArrayOutputStream();
         while ((len = inStream.read(buffer)) != -1) {
             outStream.write(buffer, 0, len);
         }
         byte[] data = outStream.toByteArray();
         outStream.close();
         inStream.close();
         return data;
     }  

     /**
      * @param 将字节数组转换为ImageView可调用的Bitmap对象
      * @param bytes
      * @param opts
      * @return Bitmap
      */
     public static Bitmap getPicFromBytes(byte[] bytes,
             BitmapFactory.Options opts) {
         if (bytes != null)
             if (opts != null)
                 return BitmapFactory.decodeByteArray(bytes, 0, bytes.length,
                         opts);
             else
                 return BitmapFactory.decodeByteArray(bytes, 0, bytes.length);
         return null;
     }  

     /**
      * @param 图片缩放
      * @param bitmap 对象
      * @param w 要缩放的宽度
      * @param h 要缩放的高度
      * @return newBmp 新 Bitmap对象
      */
     public static Bitmap zoomBitmap(Bitmap bitmap, int w, int h){
         int width = bitmap.getWidth();
         int height = bitmap.getHeight();
         Matrix matrix = new Matrix();
         float scaleWidth = ((float) w / width);
         float scaleHeight = ((float) h / height);
         matrix.postScale(scaleWidth, scaleHeight);
         Bitmap newBmp = Bitmap.createBitmap(bitmap, 0, 0, width, height,
                 matrix, true);
         return newBmp;
     }  

     /**
      * 把Bitmap转Byte
      */
     public static byte[] Bitmap2Bytes(Bitmap bm){
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
         bm.compress(Bitmap.CompressFormat.PNG, 100, baos);
         return baos.toByteArray();
     }  

     /**
      * 把字节数组保存为一个文件
      */
     public static File getFileFromBytes(byte[] b, String outputFile) {
         BufferedOutputStream stream = null;
         File file = null;
         try {
             file = new File(outputFile);
             FileOutputStream fstream = new FileOutputStream(file);
             stream = new BufferedOutputStream(fstream);
             stream.write(b);
         } catch (Exception e) {
             e.printStackTrace();
         } finally {
             if (stream != null) {
                 try {
                     stream.close();
                 } catch (IOException e1) {
                     e1.printStackTrace();
                 }
             }
         }
         return file;
     }
 }

代码很实用所以转载过来，又因为转载的也是别人转载的文章，所以出处不知道，请见谅！