Roku Developer Program

[jstwinkles]

Hi there,

I'm new to writing Roku channels, and I've run into a roadblock when trying to display high-resolution images (>1080p).  No matter what I do, the display stays at 1080p.  I can demonstrate this by using the poster node to display a known 4K reference image at its native resolution without scaling, and observing where it gets cut off the screen.  I realize that I can always scale the image down to 1080p and autofit it, but I would really like to create something like a 4k screensaver in the long run once I learn some more about the SDK.  However, information related to 4k/UHD in the documentation seems rather sparse.  Is what I want to do even possible?

Thanks in advance.

[squirreltown]

Only video is shown at 4K. The UI is 1080p max in RSG and 720p with the 2D API.
https://sdkdocs.roku.com/display/sdkdoc/Specifying+Display+Resolution

[jstwinkles]

Okay, that makes sense. Then my next question is this: how do you suppose those various 4k screensavers work? Are they just playing a 4k video stream that's made up of still images? I've got a lot of high-res images on a local NAS I would like to be able to stream as a screensaver in 4k. Does this mean I would have to bake those into a video stream first, rather than being able to have the server randomly select an image and send it to the roku one by one?

[Tajson]

UI outputs 4k when set as such for the box.

[EnTerr]

"jstwinkles" wrote:
Okay, that makes sense.  Then my next question is this: how do you suppose those various 4k screensavers work? Are they just playing a 4k video stream that's made up of still images? I've got a lot of high-res images on a local NAS I would like to be able to stream as a screensaver in 4k. Does this mean I would have to bake those into a video stream first, rather than being able to have the server randomly select an image and send it to the roku one by one?

Good question.
Have you seen any genuine 4K screensaver on Roku?
Also i am not sure if screensavers are allowed to play video... for some reason i think back in the days i saw somewhere video is disallowed

[jstwinkles]

"EnTerr" wrote:
Have you seen any genuine 4K screensaver on Roku?

Well, I thought I had seen at least one in the channel store, but I just went to look and I couldn't find any.  However, I somehow have a screensaver titled "Nature 4K UHD Screensaver" installed, and it's definitely outputting 4K, which is probably why I thought such a creature existed.  I wonder if this is some built-in Roku screensaver with special capabilities that you can't get with the normal API?

[EnTerr]

"jstwinkles" wrote:
Well, I thought I had seen at least one in the channel store, but I just went to look and I couldn't find any.  However, I somehow have a screensaver titled "Nature 4K UHD Screensaver" installed, and it's definitely outputting 4K, which is probably why I thought such a creature existed.  I wonder if this is some built-in Roku screensaver with special capabilities that you can't get with the normal API?

Me neither, i did not find others.
The "Nature 4K UHD Screensaver" screensaver comes pre-installed and is not removable. I bet it's RokuCo's own, in which case all bets what it can or cannot do are off, since they can do it outside the SDK.
Btw, same SS works also in 720p screen resolution... i imagine images get downscaled