Vlc Is Unable To Open The Mrl 39;v4l2 39;

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Harald Atta

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Aug 3, 2024, 5:18:04 PM8/3/24

to apadmisna

The Logitechs are working not so stable:
- when trying to start with the Logitech they are often reported to be busy or in use; trying once again then they are sometimes working -> [hyperiond V4L2:/dev/video0] V4l2 init failed (Cannot open '/dev/video0' error code 16, Device or resource busy)
- a stop/restart of the Logitech in NG (alpha) WebIF isn't working
- the C250 is often losing connection in NG (debug reports 'set smoothing...' often) (for the working PS3 Eye only reported once when starting); restart of NG necessary
- the C270 I can't get working in hyperion (alpha), Beta ok:
if USB Recording is in state 'off' when starting hyperiond then always a 'Stopped' is triggered after starting USB Recording from WebIf -> hyperiond V4L2:/dev/video0] Stopped
or if USB Recording is in state 'on' when starting hyperiond then -> [hyperiond V4L2:/dev/video0] start failed (VIDIOC_STREAMON error code 5, Input/output error)
- optional: test in hyperion.ngBeta, there is an additional 'Started' reported in debug, therefore the 'Stopped' bug #491 -project/hyperion.ng/issues/491 isn't existing there;
- optional: test in hyperion.ngBeta/rework, the USB cams (grabbers?) aren't working; -> [hyperiond V4L2:auto] Throws error nr: VIDIOC_DQBUF error code 22, Invalid argument; also new setting/config mechanism

So for now I will run my TV / LEDs with hyperion.ng (alpha) and the PS3 Eye cam.
Because of the possibilities to configure the cam with v4l2-ctl parameters, it is possible to get a good result in case of no auto exposure, white balancing, brightness, ...
The Eye cam is working without problems since 48h non stop, restart in WebIF is possible.
After starting hyperiond the USB Recording has to be activated because of bug #491 -project/hyperion.ng/issues/491 once.

I will follow the upcoming activities about cam usage and hope that hyperion.ng will support them because I think they are a good solution for current requirements (4k/UHD, Smart TV Apps, ...)

After restart my error V4l2 init failed (Only pixel formats UYVY, YUYV, and RGB32 are supported) disappeared but i still unable to start my hp webcam with NG the cam works well in Hyperion Classic i thinking about buying ps3 cam to try NG
giovanne so you prefer NG with ps3 cam or clasic with logitech ?

The best would be if the hyperion developers enhance the support for the cam in general, then I think every cam can work in ng
First step would be: bug #491 -project/hyperion.ng/issues/491 (unfortunately no reaction from brindosch, I think he is busy in hyperionBeta/rework :()
Maybe some issues are solved than, if we know the solution brindosch announced there...?

Hi all , i have a question maybe you can help me, for strong colors look fine but with light color look like White i check the led, and the color seem correct but at Wall look White, if i check the data pin voltage its 0.37v even if i conect direct from raspberry or arduino

Maybe i will find a ps3 eye somewhere, but for now i don't know how to start, i'm a beginner in ambilight mod. Still have no raspberry, i would like to use my android box with amlogic S905 SoC instead of raspB and install hyperion via libreElec or something else

If I understand correctly, the trapezoid tool is modifying the config.json to sample the proper areas of the screen. Fisheye would be more of a round/elliptical pattern which theoretically could be similarly adjusted (even painstakingly manually). For my setup, it may be the best option considering the placement of walls, furniture, obstructions, etc. Not sure if the 180 lens so close the the TV would work, and/or if the "internals" of HyperionNG would work.

I can verify that a normal cheapo webcam sitting on a table in front of the TV works just fine with my build of HyperionNG.

Still have my ps3 eye and Pi cam somewhere in a box, i will not use it until i buy a TV
Do you enjoy your setup ? No issue ? And by the way, did you change the exposure/gain or other setting of the PS3 eye ?

I don't quite follow your comment due to the double negative. I think you are meaning to say "it is a bad" idea. I agree with you that the trapezoid tool will not work. At this point, I think the fisheye could work (as long as hyperion is sampling the portion of the image within those little boxes)

I'd think a tool can be developed to use 4 bezier curves (one for each side of the TV) and another example getLUT() function . The center of each of the boxes could be plotted equidistant along the curve to represent the LED zones. Those bezier curves could be adjusted (by a human) to follow the warped edge of the TV. I'd even say that a user could straighten the 4 curves to simulate the trapzoid tool. Of course, there's time/effort involved in creating a tool, as those demos simply show how to draw bezier curves in a browser window.

Thinking about the fisheye/trapezoid setup. I'm thinking the black bar detection won't work so well. I imagine the black bar detection algorithm would try to traverse inward from the top/bottom outer edges in a straight horizontal line to find the non-black pixels to project to the LEDs. I could see another way to write the algorithm.

Check out this cobbled-together half-baked example using Bezier curves for definition of a fisheye LED configuration. Hacked together from this code. You can drag the handles to adjust the curves on the sample image provided by Pnp.

Since I bought a 4k TV, I was thinking about implementing a webcam as a video capture device for my ambilight as well. During my research I found this topic. I already looks very promising. However, I was wondering why we don't just write a little (independent) program that captures the webcam stream, applies some sort of affine transformation and cropping, and delivers the new (low resolution) image to hyperion via proto. There are certainly some advantages and disadvantages:

pros:
- independent of the hyperion device - any second device can provide the transformed image via wifi
- independent of hyperion and its version (despite the proto interface). It should also work with hyperion classic
- filters, driver settings, auto border detections, and similar stuff related solely to this kind of capturing can be implemented in the software without messing with hyperion

cons:
- latency may be an issue - however since the transformation itself is pretty cheap and the resolution of the resulting image is not very important, it could be feasible
- I fear that additional filters such as black border detection is not applied on images that are provided via proto (can someone confirm this?). So we woud need to implement this by ourself.

-Running Rasperry PI 3B
-Raspberry PI Camera v1.2 pi red led comes on after boot up.
-Latest Octoprint downloaded from site
-Flashed the img file into SD
-Changed WiFi network setting ie SSID and password.
-Pi connect fine to WiFi
-Gets ip via router
-I can open octoprint and configure via the IP from my PC can also SSH fine.
-I open control and web feed says unable to open web feed
-Not sure if the url that are populated automatically are correct
-Not sure if octopi.local working correctly ie can resolve it.
-I did a print via pi no problem
-Only the Camera not working

Hi I know this thread is a bit old but I have been having a lot of issues with my camera the camera works I plugged it into a different pi and it did work so I transferred the entire SD to the new one incase the old had a broken port but it still refuses to work here is the web cam log