andrewfrommelbourne / dmxwebcam

A webcam (v4l2) viewer for the Raspberry Pi console.

• 👋 Hi, I’m Andrew
• 👀 I’m interested in Linux/C++, Picosystem/C++, Linux low level graphics, ZigBee
• 🌱 I’m currently learning the minutiae of Modern C++, Python best practice.

dmxwebcam's Issues

HDMI capture device

At this moment I am testinga HDMI capture device. (I expect that device is actually a HDMI to composite to capture device.) Using this device in mplayer on an ordinary PC I receive colours.

Selected device: usbtv
 Capabilities:  video capture  read/write  streaming
 supported norms: 0 = NTSC; 1 = NTSC-M; 2 = NTSC-M-JP; 3 = NTSC-M-KR; 4 = NTSC-443; 5 = PAL; 6 = PAL-BG; 7 = PAL-H; 8 = PAL-I; 9 = PAL-DK; 10 = PAL-M; 11 = PAL-60;
 inputs: 0 = Composite; 1 = S-Video;
 Current input: 0
 Current format: YUYV

[swscaler @ 0x55d43a6fdbe0] bicubic scaler, from yuyv422 to bgra using MMXEXT
VO: [x11] 720x576 => 720x576 BGRA 
Selected video codec: [rawyuy2] vfm: raw (RAW YUY2)

When using this device with dmxwebcam, I instead see a black and white image with blue and yellow vertical lines, additionally there is heavy overscan, which does not appear using mplayer.

./dmxwebcam --fullscreen --display 1 --width 720 --height 576 --fps 25
dmxwebcam[2048]:info:video dimension 720x576 -> 720x480
dmxwebcam[2048]:error:unable to set requested fps (25)

So I think there are two individual problems: the correct source colourspace (and its potential conversion) the other capture usb stick does appear in colour. And the automatic resolution reduction.

Raspbian Bullseye: "Can't open display"?

Hi, I tried using this project on Bullseye the other day, but I haven't had any luck actually running it. The only thing that happens, no matter what options I start the program with, is that I get the error "Can't open display".

I tried on a Lite installation with no X or desktop, as well as a full LDXE environment - same result.

Has something changed lately on the OS side that would cause this issue?

Running the program kills ethernet connection

Sorry that I can't post more details about this now, but I just wanted to mention that when I run the program my ethernet connection always seems to become disconnected. Looking through the code, it didn't seem like connection settings are ever altered. It might be because my pi doesn't have enough current supplied through the USB power cord. I'll post more information as I learn more about the issue.

Right now, I just restart the pi when the internet connection is needed to transfer files from the pi.

https://github.com/AndrewFromMelbourne/dmxwebcam/issues/new

Stretch a feed to fill the screen

Hey!
Your program is everything I've been looking for the past few days. I have one question though, is there a way to re-size the video feed?
I have a USB microscope plugged into my Raspberry pi, and my pi is connected to a 4" HDMI touchscreen and the image fills only a small part in the middle. is there any way to stretch the image to fill the whole screen?

Regards.

compile error

hi just wanted to compile it on rasbian latest jesse pixel got this:

Scanning dependencies of target dmxwebcam
[ 16%] Building C object CMakeFiles/dmxwebcam.dir/dmxwebcam.c.o
/home/pi/dmxwebcam/dmxwebcam.c:43:25: fatal error: bsd/libutil.h: No such file or directory
#include <bsd/libutil.h>
^
compilation terminated.
CMakeFiles/dmxwebcam.dir/build.make:62: recipe for target 'CMakeFiles/dmxwebcam.dir/dmxwebcam.c.o' failed
make[2]: *** [CMakeFiles/dmxwebcam.dir/dmxwebcam.c.o] Error 1
CMakeFiles/Makefile2:67: recipe for target 'CMakeFiles/dmxwebcam.dir/all' failed
make[1]: *** [CMakeFiles/dmxwebcam.dir/all] Error 2
Makefile:127: recipe for target 'all' failed
make: *** [all] Error 2

any stuff i should install prior to compiling?

Exit from fullscreen

Hi,

Thanks for making this project. It's the best solution for live view of a USB webcam I've found so far, it's great.

I have a small problem. I am running on a Raspberry Pi in CLI mode. Once I have launched dmxwebcam in fullscreen, how can I exit back to CLI? Every key combo that I've tried hasn't worked. Is this possible?

Cheers and keep up the great work :)

How to set EGL layer ?

I try to use your project together with Crankshaft project (OpenAuto)
I face problem that when Android Auto starts, dmxwebcam image is not displayed, I believe it is hidden under Android auto.
Is it possible to set higer layer? Possibly additional parameter?
Similar to omxplayer parameter --layer n
--layer n Set video render layer number (higher numbers are on top)

Video over USB(2)

At this moment I am trying to receive video on the Raspberry Pi 3. Using a composite capture device I notice that if the resolution is 720x576 horizontal lines appear at parts of the screen, in a random fashion. Like the USB bus is overloaded, if the resolution is lowered to for example 500x576 these lines do not appear.

with artifacts

./dmxwebcam --fullscreen --display 1 --width 720 --height 576 --fps 25
dmxwebcam[1982]:error:unable to set requested fps (25)

without artifacts

./dmxwebcam --fullscreen --display 1 --width 500 --height 576 --fps 25
dmxwebcam[1989]:error:unable to set requested fps (25)

compilation issue

when I try to compile I get an error... kind of a noob at this stuff here is the error

pi@basestationpi:/share/dmxwebcam $ sudo make ./dmxwebcam
cc     dmxwebcam.c   -o dmxwebcam
dmxwebcam.c:53:10: fatal error: bcm_host.h: No such file or directory
 #include "bcm_host.h"
          ^~~~~~~~~~~~
compilation terminated.