title: FFMPEG Merge two videos into one with side-by-side same quality output
body: <p>I´m already working on project with 3d video an i have problem,i got left and right channel of video a a ineed to merge it into side by side.I already read some blogs about this problem and i got this code:</p>
  
  <pre><code>ffmpeg -i avatar35l.avi -vf "movie=avatar35r.avi [in1]; [in]pad=1920*2:1080[in0]; [in0][in1] overlay=1920:0 [out]" avatar35sbs.avi
  </code></pre>
  
  <p>it works,but i got significant quality loss and i need a quality of output video same as input video,30fps,1080p,same lenght,i´m a new one to ffmpeg and i need a concrete example of that</p>
  
  <p>Can anybody help me? </p>