Android的保存的图像质量低 [英] Android Saved images are low quality

问题描述

我是通过以下code拍照并保存到SD卡，但它产生的图像是这样低质量，真正甚至100％的质量片断。也许bitmap.com preSS是不正确的方式去（或位图呢？！）

我的继承人code：

 公共类TakePhoto延伸活动{    ImageView的IV;    @覆盖
    公共无效的onCreate（捆绑savedInstanceState）{
        super.onCreate（savedInstanceState）;
        的setContentView（R.layout.activity_take_photo）;
        IV =（ImageView的）findViewById（R.id.imageView1）;        按钮B =（按钮）findViewById（R.id.button1）;
        b.setOnClickListener（新OnClickListener（）{            @覆盖
            公共无效的onClick（视图v）{                意向意图=新意图（android.provider.MediaStore.ACTION_IM​​AGE_CAPTURE）;
                startActivityForResult（意向，0）;            }
        }）;
    }    @覆盖
    保护无效的onActivityResult（INT申请code，INT结果code，意图数据）{
        // TODO自动生成方法存根
        super.onActivityResult（要求code，结果code，数据）;        。位图BM =（位图）data.getExtras（）获得（数据）;
        随机数发生器=新的随机（）;
        字符串randFileName =将String.valueOf（generator.nextInt（965）+ 32）;
        这两个字符串=到/ mnt / extSdCard / DirectEnquiries /+ randFileName +.JPG;
        文件镜像文件=新的文件（两个）;        writeBitmapToMemory（镜像文件，BM）;
        iv.setImageBitmap（BM）;    }    公共无效writeBitmapToMemory（档案文件，位图位图）{
        FileOutputStream中FOS;        尝试{
            Log.e（汤姆，启动取流）;
            FOS =新的FileOutputStream（文件）;
            Log.e（汤姆，GOT流）;
            bitmap.com preSS（Bitmap.Com pressFormat.JPEG，100，FOS）;
            Log.e（汤姆，保存的图像）;
            fos.close（）;        }
        赶上（FileNotFoundException异常五）{
            e.printStackTrace（）;
        }
        赶上（IOException异常五）{
            e.printStackTrace（）;
        }    }}
 

解决方案

请拨打下面的函数从相机拍照。

 私人最终静态字符串FOLDER_NAME =YourAppName /图片/;
 私人乌里selectedImageUri = NULL;公共无效startCamera（）
    {
        文件照片= NULL;
        意向意图=新意图（android.media.action.IMAGE_CAPTURE）;
        字符串的timeStamp =新的SimpleDateFormat（YYYYMMDD_HHMMSS）格式（新的Date（））;
        如果（android.os.Environment.getExternalStorageState（）。等于（android.os.Environment.MEDIA_MOUNTED））
        {
            照片=新的文件（android.os.Environment.getExternalStorageDirectory（），FOLDER_NAME +文件分割符+的timeStamp +PNG）;
        }
        其他
        {
            照片=新的文件（getCacheDir（），FOLDER_NAME +文件分割符+的timeStamp +PNG）;
        }
        如果（照片！= NULL）
        {
            intent.putExtra（MediaStore.EXTRA_OUTPUT，Uri.fromFile（照片））;
            selectedImageUri = Uri.fromFile（照片）;
            startActivityForResult（意向，CAPTURE_IMAGE_CALLBACK）;
        }
    }
 

您可以在selectedImageUri变量获得的图像URI。 （图片存储在SD卡）

 保护无效的onActivityResult（INT申请code，INT结果code，意图数据）
    {
        开关（要求code）
        {
            案例CAPTURE_IMAGE_CALLBACK：                打破;
          }
     }
 

I'm taking pictures through the following code and saving to SD card, but the pictures that it produces are such low quality and really bitty even with 100% quality. Maybe bitmap.compress isn't the right way to go (or bitmap at all?!)

Heres my code:

public class TakePhoto extends Activity {

    ImageView iv;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_take_photo);


        iv = (ImageView) findViewById(R.id.imageView1);

        Button b = (Button) findViewById(R.id.button1);
        b.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

                Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
                startActivityForResult(intent, 0);

            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        // TODO Auto-generated method stub
        super.onActivityResult(requestCode, resultCode, data);

        Bitmap bm = (Bitmap) data.getExtras().get("data");
        Random generator = new Random();
        String randFileName = String.valueOf (generator.nextInt(965) + 32);
        String both = "/mnt/extSdCard/DirectEnquiries/"+ randFileName + ".jpg";
        File imageFile = new File(both);

        writeBitmapToMemory(imageFile, bm);
        iv.setImageBitmap(bm);

    }

    public void writeBitmapToMemory(File file, Bitmap bitmap) {
        FileOutputStream fos;

        try {
            Log.e("Tom", "Starting take stream");
            fos = new FileOutputStream(file);
            Log.e("Tom", "Got stream");
            bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
            Log.e("Tom", "Saved Image");
            fos.close();

        } 
        catch (FileNotFoundException e) {
            e.printStackTrace();


        } 
        catch (IOException e) {
            e.printStackTrace();


        }

    }

}

解决方案

Please call the below function to capture image from camera.

 private final static String FOLDER_NAME = "YourAppName/Image/";
 private Uri selectedImageUri = null;

public void startCamera() 
    {
        File photo = null;
        Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
        if (android.os.Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_MOUNTED)) 
        {
            photo = new File(android.os.Environment.getExternalStorageDirectory(), FOLDER_NAME+File.separator+timeStamp+".png");
        } 
        else 
        {
            photo = new File(getCacheDir(), FOLDER_NAME+File.separator+timeStamp+".png");
        }    
        if (photo != null) 
        {
            intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photo));
            selectedImageUri = Uri.fromFile(photo);
            startActivityForResult(intent, CAPTURE_IMAGE_CALLBACK);
        }
    }

You can get image Uri in selectedImageUri variable . (Image is stored in Sdcard)

    protected void onActivityResult(int requestCode, int resultCode, Intent data) 
    {
        switch (requestCode) 
        {
            case CAPTURE_IMAGE_CALLBACK:

                break;
          }
     }

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