Dispmanx VNC Server

[Naiw]

Yes, I assumed it would work on the old RPis now, I'm rewriting some stuff to use assembly however and that's what worries me could cause compatibility issues with the old RPi- I really want to change the detection/Blitting to use Neon but that would really be a no go on the old RPi, so currently I'm experimenting with regular ARM assembly and attempt using the barrel shifter in an efficient way.

You could always load different code based on the model. Obviously it is up to you if you want to maintain compatibility or not.

Speaking of which it's too bad valgrind/callgrind doesn't work any good on the RPi due to some god damned reason they decided to use bigendian in libconfi_rpi, I haven't decided if time is best spent attempting to rewrite that or keep on using gprof.

That is interesting to know. I haven't tried valgrind on the Raspberry Pi (not seriously at least). I didn't know hat was the problem.

Actually I just decided to start looking into it, it didn't require any significant work... just disable the libconfi_rpi in /etc/ld.so.preload

[Chips]

I wanted to try it for quite some time... now I just tried it and it works quite well.
My 2 cents:
- 30 frames per seconds is too much under X on my setup, it was heavily lagging, I lowered it to 10 and it's better. Automatic frame rate would be better though...
- Keyboard is qwerty... whereas I do have azerty on both my host and client. This problem is common with ultra & tight client. Never had this issue with others server... I have no idea how it is handled anyway, I could have miss something
- Since Rpi can do hardware jpeg compression, it could be an added optimization... but I prefer lossless compression

I used it to take screen-shoot of some emulators :
viewtopic.php?p=738464#p738464
Since I play a little bit with emulators using dispmanx it helps me since others vnc don't forward dispmanx layers but this one does...

[AndyD]

...- Since Rpi can do hardware jpeg compression, it could be an added optimization...

Yes, I wonder how hard it would be to write a drop in replacement for libjpeg that uses the GPU?

[dom]

Yes, I wonder how hard it would be to write a drop in replacement for libjpeg that uses the GPU?

libjpeg is not very amenable to hardware accelerating. It has an api that allows requesting the decoded jpg a line of pixels at a time.

Probably if you go up one level into vnc, there will be something more convenient. Ideally something like:
int jpg_encode(unsigned char *pixels, int width, int height, int pitch, unsigned char **output_jpg, int *size);

That sort of API could be accelerated straightforwardly.

[postpunkpl]

Hello,

Is it possible to change a resolution? I have only 640x480 px.

greetings,

Peter

[AndyD]

Is it possible to change a resolution? I have only 640x480 px.

Yes it is possible. The DIspmanX VNC Server copies the Raspberry Pi display. If you are using your Raspberry Pi without a connection to a display, then to change the resolution that DispmanX VNC Server uses you would need to configure the Raspberry Pi to make it believe it has a display attached with the resolution that you require.

I hope that makes sense.

[postpunkpl]

yes, it make sense but how to configure that resolution?

[AndyD]

To always have a certain resolution set, you can use hdmi_force_hotplug=1 and set the specific resolution you want using hdmi_group and hdmi_mode. The modes are listed in the config.txt documentation. For example 1280x1024 @60Hz

Code: Select all

hdmi_force_hotplug=1
hdmi_group=2
hdmi_mode=35

If you require a mode that is not listed there you can specify a custom mode. Here is my config that I use to have the same native resolution (480x320) as my add-on TFT display.

Code: Select all

hdmi_force_hotplug=1
hdmi_cvt=480 320 60
hdmi_group=2
hdmi_mode=87

NOOBs sets the hdmi_force_hotplug=1 by default. I think you already have this set as 640x480 is the resolution you get by default with hdmi_force_hotplug=1.

[postpunkpl]

thank you so much it is very useful

[JGR79]

Hello, i need something that looks like simple , but i cant make it work.

I need to reproduce the content of the RPI2 Screen remotely via web browser.

Without X11, i found dispmanx server that works like a charm, its perfect. At this point, .

Now i need to record that session , i use vncrec, in the same host, the same RPI2 that runs the server. But it didn't work.

Error: Can't open display:

if i can record that vnc session , the next step is ffmpeg and crtmpserver and ........ the video on the web.

Any help?

[AndyD]

Error: Can't open display:

I think the problem is that vncrec is an X11 application.

[JGR79]

any alternative?

[gatalon]

Hi, this VNC Server is very good.
But i face some problems when use vnc client on my laptop, the numberpad not work in Windows system, The Right Shift Button and the Right Ctrl Button upside down in ubuntu system whatever vncclient software i use，I have checked the source code on your github found this
Is there something wrong here carried my problem?
sorry for my poor english.

[gatalon]

I have fixed shift, alt, ctrl bugs my self, but i still can't use numberpad of my keyboard. because i'm not good at C++.
else if (code>=0xFFE1 && code<=0xFFEE) {
static const uint16_t map[] =
{ 0, KEY_LEFTSHIFT,
KEY_RIGHTSHIFT, KEY_LEFTCTRL,
KEY_RIGHTCTRL, KEY_CAPSLOCK,
0, 0,
0, KEY_LEFTALT,
KEY_RIGHTALT, 0, 0, 0 };
scancode = map[code & 0xF];

[RpiName]

More efficient and flexible alternative:

https://www.youtube.com/watch?v=wthS8TP ... e=youtu.be

for more info:
http://linux-projects.org

[Ickam]

This question will probably sound very silly, but: how do I use this to control kodi on raspberry 3? I've tried running it from both another instance of vnc, and ssh and in both cases i get something along the lines of

Code: Select all

pi@malina:~/dispmanx_vnc $ sudo ./dispmanx_vncserver
Read config file: ./dispmanx_vncserver.conf
Running vnc server with the following settings
  frame-rate = 15
  downscale = false
  fullscreen = false
  localhost = true
  multi-threaded = true
  password =
  port = 9003
  relative = false
  screen = 0
  unsafe = false
  vnc-params =
Open display[0]...
info: 720, 480, 0, 0
Display is 720 x 480
Server bpp:16
Server bigEndian:0
Server redShift:0
Server blueShift:10
Server greeShift:5
16/05/2017 16:40:42 ListenOnTCPPort: Address already in use
open /dev/uinput returned 5.
First write returned 1116.
ioctl UI_DEV_CREATE returned 0.
open /dev/uinput returned 6.
First write returned 1116.
ioctl UI_DEV_CREATE returned 0.

I'd love to make this work, but I don't know where to start

[amilino]

This question will probably sound very silly, but: how do I use this to control kodi on raspberry 3? I've tried running it from both another instance of vnc, and ssh and in both cases i get something along the lines of

Code: Select all

pi@malina:~/dispmanx_vnc $ sudo ./dispmanx_vncserver
Read config file: ./dispmanx_vncserver.conf
Running vnc server with the following settings
  frame-rate = 15
  downscale = false
  fullscreen = false
  localhost = true
  multi-threaded = true
  password =
  port = 9003
  relative = false
  screen = 0
  unsafe = false
  vnc-params =
Open display[0]...
info: 720, 480, 0, 0
Display is 720 x 480
Server bpp:16
Server bigEndian:0
Server redShift:0
Server blueShift:10
Server greeShift:5
16/05/2017 16:40:42 ListenOnTCPPort: Address already in use
open /dev/uinput returned 5.
First write returned 1116.
ioctl UI_DEV_CREATE returned 0.
open /dev/uinput returned 6.
First write returned 1116.
ioctl UI_DEV_CREATE returned 0.

I'd love to make this work, but I don't know where to start

Don't understand what is the problem. I have the same output and everything is working fine.

[chengjianwen]

Does anyone known why uinput don't work under X?

I installed dispmanx_vncserver on raspbian, raspbian lite and Raspbian full. It seems there without keyboard and mouse under X.

The modules uinput and evdev are loaded. I searched everywhere and can't find any useful help about it.

Thanks

[jamesh]

Does anyone known why uinput don't work under X?

I installed dispmanx_vncserver on raspbian, raspbian lite and Raspbian full. It seems there without keyboard and mouse under X.

The modules uinput and evdev are loaded. I searched everywhere and can't find any useful help about it.

Thanks

Please start a new thread - this one is ancient.

[webdawg]

I am sorry to revive such an old thread, but since this forum does not have a direct message function:

I am trying to understand the difference between:

https://github.com/hanzelpeter/dispmanx_vnc

And

https://github.com/patrikolausson/dispmanx_vnc

The patrikolausson seems to work better then the hanzelpeter one.

The reason I post is here is:

This is the topic that started this, and I am hoping that hanzelpeter gets a notification.

[AndyD]

This might explain it https://github.com/hanzelpeter/dispmanx ... rk/members
The code was originally written by Hanzel Peter. It was then forked by Patrik Olasusson and modified or re-written.

[hanzelpeter]

Hello.

Yes original code was written by me. It was just for fun. I am not maintaining it very much. RealVNC server has now possibility to do the same as dispmanx vnc. I also have some problems with keys and with libinput. Just not have enough tíme to work on fix.

[amilino]

One question, now that I am using higher resolution (4096 x 2160) in Kodi, dispmanx is not working. Can I specify resolution in config file as a parameter or "vnc-params" parameter? I know I can specify hdmi resolution in /boot/config.txt file but I don't want to do that, because I want to have specific resolution only for vnc.

[hanzelpeter]

Hello. What type of RPI is dispmanx vnc not working? Is it RPI4? Dispmanx vnc is takíng screenshots from actual resolution. So the donwsampling resolution would require to implement it. (Sounds like nice feature to add...)

[amilino]

Yes, RPi 4.