Capturing desktop and streaming it to NDS
- linux
- DevkitPro, easiest way to download it is through pacman: https://devkitpro.org/wiki/Getting_Started
- create hotspot on your laptop
- run .nds file on your NDS
- connect to your hotspot on your NDS via the .nds file
- run the python script: desktop_client.py
- NDS opens port 8080, python script connects PC to it, then:
- python makes screenshot,
- resizes it to 256px or 128px (depends how smooth transmition you want - 256px takes ~ 0.6s on frame, 128px - ~0.3s)
- calls grit to make a 16 bit, lz77 compressed raw binary version
- sends image size to the NDS
- sends image
- receives ACK character from NDS
- repeat
- in Ubuntu open "Network Connections" and click "add new"
- go to the "Wi-Fi security" - NDS supports only WEP security (so remember, it's dangerous to beacon that poorly secured network all the time, use this hotspot only when playing with your NDS) - select "WEP 40/128 bit key (Hex or ASCII)"
- select some random 5 character (only digits) password
- in "Wi-Fi" tab select "Mode" to "Hotspot"
- save it
- open "Network"
- click "Connect to to a hidden network"
- select network that you've just created (by default its name will be "hotspot")
- you're done, if you were previously connected with another network via wifi you'll be disconnected
- now you can connect to this network through your NDS
Well... as it's only sending lz77 compressed bitmaps through the network, you won't be suprised that for a 2004 portable console that much of bytes will be a shock therapy. On average it's somewhere between 10-20 kB per 256px frame and 5-10 per 128px frame. Every frame must be decompressed on NDS (it has a dedicated hardware for that so it's not that bad in this task) and that's the thing that takes most of the time (around 2/3 of frame time). I tried sending non-compressed bitmaps but it took around 80kB per each and it took even more time (this time the WiFi capabilities of the NDS were the bottleneck).
- Can I control my desktop through this app?
- You could do it, I even created one version that you can access on this video:
- https://www.youtube.com/watch?v=WR8Y4Iro9t0
- ...but it's almost no use because I can't utilize multiple threads on NDS so capturing input will occure every frame - that means it will happen every ~0.3 second - so it's basically garbage.
- If you're interested only in capturing key input (without the video part), I created another program:
- https://github.com/dbeef/pc-controller-ds