发送后位图质量不好（Android / Java）

Question

I'm getting a Bitmap with:

View v1 = (View) wpm.getParent().getParent();

        Bitmap cs = null;
        v1.setDrawingCacheEnabled(true);
        v1.buildDrawingCache(true);
        cs = Bitmap.createBitmap(v1.getDrawingCache(true));
        Canvas canvas = new Canvas(cs);
        v1.draw(canvas);
        canvas.save();
        v1.setDrawingCacheEnabled(false);

        String path = Images.Media.insertImage(getContext().getContentResolver(), cs, "MyImage", null);
        Uri file = Uri.parse(path);

        OutputStream outStream = null;
        try {
            outStream = getContext().getContentResolver().openOutputStream(file);
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        cs.compress(Bitmap.CompressFormat.JPEG, 100, outStream);

        //file senden
        Intent sharingIntent = new Intent(Intent.ACTION_SEND);
        sharingIntent.putExtra(Intent.EXTRA_STREAM, file);
        sharingIntent.setType("image/jpeg");
        getContext().startActivity(Intent.createChooser(sharingIntent,"Erfolg teilen!"));

When I send it via Facebook, Whatsapp,... the Quality is very bad. But if I copy it to my PC it looks normally and before I send it via Facebook I can check how it will look and there it looks normally too. Only after sending it it looks bad. How can I change this?

Answer 1

Try to set:

yourView.setDrawingCacheQuality(View.DRAWING_CACHE_QUALITY_HIGH);

If your starting bitmap have a bad quality, you can't make it better with bitmap.compress.

REMEMBER that better quality need more memory.

Answer 2

The problem comes from the following line:

cs.compress(Bitmap.CompressFormat.JPEG, 100, outStream);

The quality 100 is too high, and the size of generated jpg file is too large to be accepted by Facebook. So Facebook compresses this image and reduces its quality. Use the following code may solve your problem:

cs.compress(Bitmap.CompressFormat.JPEG, 70, outStream);