如何轉換的byte []沒有損失位圖質量

Question

我的目標是從攝像機onPictureTaken

到

1. 捕獲字節的byte []轉換爲位圖BitmapFactory.decodeByteArray
2. 保存位圖

我有步驟2中的問題。此步由於某種原因使PICT脲含有鋸齒狀邊緣和質量損失。如果我執行步驟1並將字節直接保存到文件中（不執行第2步），則圖像看起來好多了。

如何在不丟失質量的情況下將字節轉換爲位圖（步驟2）？

@Override 
public void onPictureTaken(byte[] byteData, Camera camera) { 
    String filePath = "PATH_TO_IMAGE_FILE"; 

    //Save bytes directly 
    { 
     File pictureFile = new File(filePath + ".fromBytes"); 

     try { 
      FileOutputStream fos = new FileOutputStream(pictureFile); 
      fos.write(byteData); 
      fos.close(); 


     } catch (Exception error) { 
      Log.d("File not saved: " , error.getMessage()); 

     } 
    } 

    //convert to bitmap -> convert to bytes -> then save 
    { 
     //I think this is where is loses quality ?? 
     Bitmap decodedBitmap = BitmapFactory.decodeByteArray(byteData, 0, byteData.length); 
     // 

     ByteArrayOutputStream blob = new ByteArrayOutputStream(); 
     decodedBitmap.compress(Bitmap.CompressFormat.PNG, 100, blob); 
     byte[] bitmapdata = blob.toByteArray(); 
     File pictureFile = new File(filePath + ".fromBitmap"); 

     try { 
      FileOutputStream fos = new FileOutputStream(pictureFile); 
      fos.write(bitmapdata); 
      fos.close(); 


     } catch (Exception error) { 
      Log.d("File not saved: " , error.getMessage()); 

     } 
    } 
} 

感謝

Answer 1

變化：

decodedBitmap.compress(Bitmap.CompressFormat.PNG, 100, blob); 

這樣：

decodedBitmap.compress(Bitmap.CompressFormat.JPEG, 100, blob);