but I don’t understand what means "Non-partnered channels" in this? And how many viewers should be on channel (“don’t have enough viewers”)? “Non-partnered channels or channels that just don’t have enough viewers will only have one URL in the response, channels that are partnered/have enough viewers and are transcoded will contain URL’s for “Source”, “High”, “Medium”, “Low” and “Mobile” quality levels.”
Partnered channels have an agreement with twitch and can play ads, have quality options, and have the option for users to subscribe to them. A stream will also get quality options if it is one of the top 100 viewed streams on twitch (IIRC).