以高分辨率保存画布图像

Question

I am creating an android app where an user can draw, add text or image on to the canvas. After the user has finished editing on th canvas there is an option for saving. When I try to save that as an image, the resulting output image is of very low resolution.

            canvas.setDrawingCacheEnabled(true);                
            canvas.setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH);
            Bitmap bitmap = canvas.getDrawingCache();
            String path = Environment.getExternalStorageDirectory().getAbsolutePath();
            File file = new File(path+"/image.jpg");
            FileOutputStream ostream;
            try {
                file.createNewFigle();
                ostream = new FileOutputStream(file);
                bitmap.compress(CompressFormat.JPEG, 100, ostream);
                ostream.flush();
                ostream.close();
                Toast.makeText(getApplicationContext(), "image saved", 5000).show();
            } catch (Exception e) {
                e.printStackTrace();
                Toast.makeText(getApplicationContext(), "error", 5000).show();
            }

I want the image to be saved as A3 300dpi. Is there any possible way?

Answer 1

尝试将文本，图像和所有绘图保存为对象，当用户单击保存按钮时，创建一个具有所需分辨率的新位图，并将当前画布转换为所需的位图

Answer 2

I think this is because of using bitmap.compress(CompressFormat.JPEG, 100, ostream); use PNG instread of JPEG Hope you be ok