java 安卓bitmap低质量问题

Question

我刚刚创建了一些函数从相机中拍摄照片，并将结果图像放入imageview。我发现我的照片质量太差了

以下是一些代码：

 @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (requestCode == CAMERA_REQUEST && resultCode == RESULT_OK) {
            Bitmap photo = (Bitmap) data.getExtras().get("data");
            picture.setImageBitmap(photo);
        }
    }

View.OnClickListener camerabtnlistener = new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            startActivityForResult(cameraIntent, CAMERA_REQUEST);
        }
    };


@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_admin_help_3);
        btnPicture = (Button) findViewById(R.id.btnPicture);
        picture= (ImageView) findViewById(R.id.picture);
        mToolbar = (Toolbar) findViewById(R.id.toolbar);
        layoutPic = (RelativeLayout) findViewById(R.id.layoutPic);
        setSupportActionBar(mToolbar);

        getSupportActionBar().setDisplayOptions(ActionBar.DISPLAY_SHOW_HOME, ActionBar.DISPLAY_SHOW_CUSTOM);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setHomeButtonEnabled(true);

        btnPicture.setOnClickListener(camerabtnlistener);

    }

还有xml

<ImageView
            安卓:id="@+id/picture"
            安卓:layout_width="fill_parent"
            安卓:layout_height="wrap_content"
            安卓:src="@drawable/test_admin_big"
            安卓:adjustViewBounds="true"/>

我已经在下面尝试了这些解决方案，但不起作用

1. Resizing ImageView to fit to aspect ratio
2. Fit image into ImageView, keep aspect ratio and then resize ImageView to image dimensions?
3. Android bitmap quality issues

请告知

多谢各位

Answer 1

与此相反，只需创建自己的文件夹&；在为相机创建意图时给出其uri，例如： Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); fileUri = GetOutpoutMediaFileUri.getOutputMediaFileUri(MEDIA_TYPE_IMAGE); intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); startActivityForResult(intent, 0)

Answer 2

如果使用Bundle extras=数据。getExtras（）；在onActivityResult中，它将返回缩略图图像，而不是实际图像

下面是我用来捕获和保存相机图像并将其显示到imageview的代码

您必须将相机图像保存到特定位置，然后从该位置提取

下面是打开“捕获相机图像”活动的方法

private static final int CAMERA_PHOTO = 111;
private Uri imageToUploadUri;

private void captureCameraImage() {
        Intent chooserIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        File f = new File(Environment.getExternalStorageDirectory(), "POST_IMAGE.jpg");
        chooserIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
        imageToUploadUri = Uri.fromFile(f);
        startActivityForResult(chooserIntent, CAMERA_PHOTO);
    }

那么你的onActivityResult（）方法应该是这样的

  @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {
            super.onActivityResult(requestCode, resultCode, data);

            if (requestCode == CAMERA_PHOTO && resultCode == Activity.RESULT_OK) {
                if(imageToUploadUri != null){
                    Uri selectedImage = imageToUploadUri;
                    getContentResolver().notifyChange(selectedImage, null);
                    Bitmap reducedSizeBitmap = getBitmap(imageToUploadUri.getPath());
                    if(reducedSizeBitmap != null){
                        imageview.setImageBitmap(reducedSizeBitmap);
                    }else{
                        Toast.makeText(this,"Error while capturing Image",Toast.LENGTH_LONG).show();
                    }
                }else{
                    Toast.makeText(this,"Error while capturing Image",Toast.LENGTH_LONG).show();
                }
            } 
        }

下面是onActivityResult（）中使用的getBitmap（）方法

private Bitmap getBitmap(String path) {

        Uri uri = Uri.fromFile(new File(path));
        InputStream in = null;
        try {
            final int IMAGE_MAX_SIZE = 1200000; // 1.2MP
            in = getContentResolver().openInputStream(uri);

            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(in, null, o);
            in.close();


            int scale = 1;
            while ((o.outWidth * o.outHeight) * (1 / Math.pow(scale, 2)) >
                    IMAGE_MAX_SIZE) {
                scale++;
            }
            Log.d("", "scale = " + scale + ", orig-width: " + o.outWidth + ", orig-height: " + o.outHeight);

            Bitmap b = null;
            in = getContentResolver().openInputStream(uri);
            if (scale > 1) {
                scale ;
                // scale to max possible inSampleSize that still yields an image
                // larger than target
                o = new BitmapFactory.Options();
                o.inSampleSize = scale;
                b = BitmapFactory.decodeStream(in, null, o);

                // resize to desired dimensions
                int height = b.getHeight();
                int width = b.getWidth();
                Log.d("", "1th scale operation dimenions - width: " + width + ", height: " + height);

                double y = Math.sqrt(IMAGE_MAX_SIZE
                        / (((double) width) / height));
                double x = (y / height) * width;

                Bitmap scaledBitmap = Bitmap.createScaledBitmap(b, (int) x,
                        (int) y, true);
                b.recycle();
                b = scaledBitmap;

                System.gc();
            } else {
                b = BitmapFactory.decodeStream(in);
            }
            in.close();

            Log.d("", "bitmap size - width: " + b.getWidth() + ", height: " +
                    b.getHeight());
            return b;
        } catch (IOException e) {
            Log.e("", e.getMessage(), e);
            return null;
        }
    }

我希望有帮助