Question

我正在创建一个Android应用程序，用户可以点击图像一旦捕获图像将在网格视图中显示这部分工作正常但图像质量非常低，即使我从中获取图像在高分辨率相机中，它分别显示图像的宽度和高度为160和200像素。我想知道有没有办法捕获原始大小的图像，而不是压缩图像我们在whatsapp中做什么。因为我是android的新手，所以我不知道自己要做什么。

public class CamAct extends Activity implements OnClickListener {
Button captureBtn = null;
final int CAMERA_CAPTURE = 1;
private Uri picUri;
private DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
private GridView grid;
private  List<String> listOfImagesPath;

public static final String GridViewDemo_ImagePath = Environment.getExternalStorageDirectory().getAbsolutePath() + "/GridViewDemo/";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.camlayout);

    captureBtn = (Button)findViewById(R.id.capture_btn1);
    captureBtn.setOnClickListener(this);
    grid = ( GridView) findViewById(R.id.gridviewimg);

    listOfImagesPath = null;
    listOfImagesPath = RetriveCapturedImagePath();
    if(listOfImagesPath!=null){
        grid.setAdapter(new ImageListAdapter(this,listOfImagesPath));
    }
}


@Override
public void onClick(View arg0) {    
    if (arg0.getId() == R.id.capture_btn1) {
         try {  
            Intent captureIntent = new      Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(captureIntent, CAMERA_CAPTURE);
        } catch(ActivityNotFoundException anfe){
            String errorMessage = "Whoops - your device doesn't support capturing images!";
            Toast toast = Toast.makeText(this, errorMessage, Toast.LENGTH_SHORT);
            toast.show();
        }
    }
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (resultCode == RESULT_OK) {
        if(requestCode == CAMERA_CAPTURE){
            Bundle extras = data.getExtras();
            Bitmap thePic = extras.getParcelable("data");
            String imgcurTime = dateFormat.format(new Date());
            File imageDirectory = new File(GridViewDemo_ImagePath);
            imageDirectory.mkdirs();
            String _path = GridViewDemo_ImagePath + imgcurTime+".jpg";
            try {
                FileOutputStream out = new FileOutputStream(_path);
                thePic.compress(Bitmap.CompressFormat.JPEG, 90, out);
                out.close();
            } catch (FileNotFoundException e) {
                e.getMessage();
            } catch (IOException e) {
                e.printStackTrace();
            }
            listOfImagesPath = null;
            listOfImagesPath = RetriveCapturedImagePath();
            if(listOfImagesPath!=null){
                grid.setAdapter(new ImageListAdapter(this,listOfImagesPath));
            }
        }
    }
}

private List<String> RetriveCapturedImagePath() {
    List<String> tFileList = new ArrayList<String>();
    File f = new File(GridViewDemo_ImagePath);
    if (f.exists()) {
        File[] files=f.listFiles();
        Arrays.sort(files);

        for(int i=0; i<files.length; i++){
            File file = files[i];
            if(file.isDirectory())
                continue;
            tFileList.add(file.getPath());
        }
    }
    return tFileList;
}

ImageAdapter：

 public class ImageListAdapter extends BaseAdapter
{
    private Context context;
    private List<String> imgPic;
    public ImageListAdapter(Context c, List<String> thePic)
    {
        context = c;
        imgPic = thePic;
    }
    public int getCount() {
        if(imgPic != null)
            return imgPic.size();
        else
            return 0;
    }

    //---returns the ID of an item---
    public Object getItem(int position) {
        return position;
    }

    public long getItemId(int position) {
        return position;
    }

    //---returns an ImageView view---
    public View getView(int position, View convertView, ViewGroup parent)
    {
        ImageView imageView;
        BitmapFactory.Options bfOptions=new BitmapFactory.Options();
        bfOptions.inDither=false;                     //Disable Dithering mode
        bfOptions.inPurgeable=true;                   //Tell to gc that whether it needs free memory, the Bitmap can be cleared
        bfOptions.inInputShareable=true;              //Which kind of reference will be used to recover the Bitmap data after being clear, when it will be used in the future
        bfOptions.inTempStorage=new byte[16 * 1024];
        if (convertView == null) {
            imageView = new ImageView(context);
            imageView.setLayoutParams(new GridView.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
            imageView.setPadding(0, 0, 0, 0);
        } else {
            imageView = (ImageView) convertView;
        }
        FileInputStream fs = null;
        Bitmap bm;
        try {
            fs = new FileInputStream(new File(imgPic.get(position).toString()));

            if(fs!=null) {
                bm=BitmapFactory.decodeFileDescriptor(fs.getFD(), null, bfOptions);
                imageView.setImageBitmap(bm);
                imageView.setId(position);
                imageView.setLayoutParams(new GridView.LayoutParams(200, 160));
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally{
            if(fs!=null) {
                try {
                    fs.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return imageView;
    }
}

Answer 1

试试这个：

  captureBtn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            if(subname.getText().toString().isEmpty()){
                Snackbar.make(view, "Select Subject", Snackbar.LENGTH_LONG).show();

            }else {
                Intent intent = new Intent(
                        android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
                ImagefileUri = Uri.fromFile(getFile());

                intent.putExtra(MediaStore.EXTRA_OUTPUT, ImagefileUri);
                startActivityForResult(intent, CAMERA_PIC_REQUEST);
            }
        }
    });

protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (resultCode == RESULT_OK) {

        if(requestCode == CAMERA_PIC_REQUEST){
            Display display = getWindowManager().getDefaultDisplay();
            Point size = new Point();
            display.getSize(size);
            int dw = size.x;
            int dh = size.y;
            // Load up the image's dimensions not the image itself
            BitmapFactory.Options bmpFactoryOptions = new BitmapFactory.Options();
            bmpFactoryOptions.inJustDecodeBounds = true;
            Bitmap bmp = BitmapFactory.decodeFile(ImagefileUri.getPath(),
                    bmpFactoryOptions);
            int heightRatio = (int) Math.ceil(bmpFactoryOptions.outHeight
                    / (float) dh);
            int widthRatio = (int) Math.ceil(bmpFactoryOptions.outWidth
                    / (float) dw);
            Log.v("HEIGHTRATIO", "" + heightRatio);
            Log.v("WIDTHRATIO", "" + widthRatio);
            if (heightRatio > 1 && widthRatio > 1) {
                if (heightRatio > widthRatio) {
                    // Height ratio is larger, scale according to it
                    bmpFactoryOptions.inSampleSize = heightRatio;
                } else {
                    // Width ratio is larger, scale according to it
                    bmpFactoryOptions.inSampleSize = widthRatio;
                }
            }
            // Decode it for real
            bmpFactoryOptions.inJustDecodeBounds = false;
            bmp = BitmapFactory.decodeFile(ImagefileUri.getPath(),
                    bmpFactoryOptions);
            InitilizeGridLayout();

            // loading all image paths from SD card
            imagePaths = utils.getFilePaths();

            // Gridview adapter
            adapter = new GridViewImageAdapter(Cam.this, imagePaths,
                    columnWidth);

            // setting grid view adapter
            gridView.setAdapter(adapter);

        }

    }else if (resultCode == RESULT_CANCELED) {
        // user cancelled Image capture
        Toast.makeText(getApplicationContext(),
                "User cancelled image capture", Toast.LENGTH_SHORT).show();
    } else {
        // failed to capture image
        Toast.makeText(getApplicationContext(),
                "Sorry! Failed to capture image", Toast.LENGTH_SHORT)
                .show();
    }
}

它将根据相机的宽度和高度捕获图像，这样您将获得高质量的图像，以及您使用的图像适配器具有临时存储空间，只能存储5或6个高质量的图像，因此更改网格视图。要了解有关从sdcard到gridview显示图像的更多信息，请使用以下链接：Loading images from sdcard and display it in gridview

希望此代码可以帮助您：）

gridview中捕获的图像质量较低

1 个答案: