What can I do with this?

With the new Ultimate 64 firmware (>=1.1c) there is an option to receive video frames & audio over a network connection at 50fps.

You can use this tool to capture those frames into an image, audio or video file.

Changelog v1.25 (14/07/2021):

• ~ Fixed: Double click on maximized window did not reset window to normal.
• ~ Fixed: FPS calculation was wrong, fixed it.
• ~ Fixed: Exception raised when window is minimised.
• ~ Fixed: Various window position/size, save/restore issues.
• ~ Fixed: some remote function crashed app when u64 is not reachable.
• ~ Fixed: Menu is not controllable with keys anymore to prevent accidentally stop of stream.
• ~ Update: .Net FrameWork 4.6.1 to 4.8
• ~ Update: Optimized scanline simulation, total new processing.
• + Added: Context menu, to open several function from the output window.
• + Added: Multi frame capture function, capture xx frames to PNG files. Can be used to capture interlaced images.
• + Added: Multi Frame Capture viewer, can be opened from the context menu.
• + Added: CRTL+R function to reload last opened file (via dialog or drag and drop)
• + Added: Ping stats to diag window.
• + Added: Handling connection errors, added screens.

Download: U64 Streamer v1.25 (568)

source: u64streamer