title: What is the PNG files in Lottie? Are they vectorized?
body: <p>I got Lottie files from the designer and it contains <code>png</code> files.</p>
  
  <p>The size are small. However, it seems low quality. And I added it into the view and built and launched my app and It looks blurry.</p>
  
  <p>What I guess is, The parts Lottie can't vectorize remains as <code>PNG</code> files. And the others are in <code>json</code>.</p>
  
  <p>Is that right?</p>
  
  <p>If yes, The second question is, <code>Lottie</code> has some functionality to use <code>PNG</code> files like vectorized image source with its connected <code>json</code> file?</p>
  
  <p>I need to correspond the device screens(resolutions). Does <code>json+PNG</code> can correspond all the resolutions or not? If it is not, Should I separate them and for the PNG part, I need <code>mdpi</code>, <code>hdpi</code>, <code>xdpi</code>, ... ones like in Zeplin?</p>