Yes - as Marie says, you need a good connection - i.e. A good bandwidth. If the bandwidth (Mbps) is poor the encoding protocol used for the video compresses the images in order to adapt to the poor bandwidth. In doing so, the image quality inevitably suffers. Check out what bandwidth - Mbps - you've currently got. WiFi too adapts to the link quality dynamically. If the signal strength/link quality is poor, the WiFi protocol reduces the data rate in order to be able to operate under the poorer conditions.
Tim