问题
I am trying to play a 1080p@60fps HEVC stream on a Roku-4 device. I am facing some issues and I have explained it in this question - Roku: Playback is not smooth on Roku-4 device for 1080p@60fps HEVC content
I looked at the SDK documentation of Roku and found some parameters. I have some questions.
1) isHD: This is a flag to indicate the content is HD.
2) FullHD: This is a flag to indicate 1080p content.
3) FrameRate: To specify content frame rate if content is 1080p.
My questions are, 1) What is the purpose of these flags? Do they configure the player internally? Or they are just used for playlist selection in case of streaming?
2) What happens if I don't set these flags and play 720p/1080p content?
3) Why should I specify FrameRate only if content is 1080p? How Roku determines frame rate if content is of some other resolution?
4) According to document, FrameRate can take only two values - 24 and 30. How can I play 60fps content? Is the document not updated?
5) In normal case, I will just have a URL in my application. I don't have any information like frame rate or resolution. What value should I set for these parameters?
来源：https://stackoverflow.com/questions/38781614/roku-how-to-use-ishd-fullhd-framerate-parameters