Question

我正在从图库中获取图像，并试图降低其质量，然后再将其上传到服务器上，但是我没有正确的方法。

下面是我的代码：

 openGallery.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {

            Intent i = new Intent();
            i.setType("image/*");
            i.setAction(Intent.ACTION_GET_CONTENT);
            startActivityForResult(Intent.createChooser(i,"Select picture"),GALLERY_IMAGE);
        }
    });

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

    if(requestCode == GALLERY_IMAGE && resultCode == RESULT_OK && data != null){

        selectedImage = data.getData();

        Bitmap bitmap = null;

        try {

             bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(),selectedImage);


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

        }

          if(bitmap !=  null){

              bookImage.setImageBitmap(bitmap);
          }

      }

    else{

        TastyToast.makeText(getApplicationContext(),"No image selected",TastyToast.LENGTH_SHORT,TastyToast.INFO).show();

    }
}

请让我知道我应该在上面的代码中添加些什么才能获得结果，我们将不胜感激。

谢谢

Answer 1

我使用以下代码缩小和设置JPG质量。下面的代码将JPG流保存到文件中，但是您应该能够发送到内存流和字节数组。

话虽如此，您还应该考虑让ANDROID向您返回缩小的图片。特别是对于较旧的设备，您的应用程序可能没有足够的内存来存储完整尺寸的图片。抱歉，我没有任何代码可让您执行此操作。

            // Shrink to fit picture in a max size
        Point newSize = util.fitSizeInBounds(new Point(rawBitmap.getWidth(), rawBitmap.getHeight()), new Point(_maxPicSize, _maxPicSize));
        if (rawBitmap.getWidth() > newSize.x || rawBitmap.getHeight() > newSize.y) {
            scaledBitmap = Bitmap.createScaledBitmap(rawBitmap, newSize.x, newSize.y, false);
            // Because I was concerned about memory leaks, I call recycle, but maybe this is not nessessary
            rawBitmap.recycle(); rawBitmap = null;
        }
        else {
            scaledBitmap = rawBitmap; rawBitmap = null;
        }

        // Save file
        try {
            FileOutputStream outStream = new FileOutputStream(_tempDir + fileName);
            if (ext.equals("png")) scaledBitmap.compress(Bitmap.CompressFormat.PNG, 100, outStream);
            else scaledBitmap.compress(Bitmap.CompressFormat.JPEG, 70, outStream);  // Here you can compress JPG (70% quality here)
            outStream.close();
        }
        catch (Exception e) {}



public Point fitSizeInBounds(Point size, Point bounds) {

    // return size that can fit in bounds.  Result will keep same proportion as orig size
    int newWidth = size.x;
    int newHeight = size.y;

    if (newWidth > bounds.x) {
        newHeight = (newHeight * bounds.x) / newWidth;
        newWidth = bounds.x;
    }
    if (newHeight > bounds.y) {
        newWidth = (newWidth * bounds.y) / newHeight;
        newHeight = bounds.y;
    }
    return new Point(newWidth, newHeight);
}

在服务器上上传图像之前如何降低图像质量

1 个答案: