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3

The Pi Compute Module's stereoscopic support causes captures (and video recordings) to produce frames containing images from both attached cameras, either side-by-side or top-and-bottom, depending on how the camera was configured on startup. There are various restrictions on resolution (and other things) when working with stereoscopic mode, which 6by9 ...


3

Thanks, JP. I followed your instructions and got my Logitech cam streaming successfully. Just the following notes for anyone interested, based on my experience: Did not need uv4l-xmpp-bridge (at least for basic streaming) uvc driver configuration file defaults streaming to port 8090 (not 8080 as in your example). Needed a powered USB hub to get my camera ...


3

I found it. Just needed to add i.e. --config-file=/etc/uv4l/uv4l-uvc.conf to the uv4l command, you will have to create the config file first.


2

In case it helps anyone, I never managed to get this working using uv4l. Shame, as uv4l was the only approach I tried that could stream from the pi in near real-time to a browser. I did find an alternate solution based on http://pi.gbaman.info/?p=150 that worked for me, but viewing the stream requires gstreamer instead of a browser on the viewing machine. ...


2

sudo rpi-update then working fine BRG


2

To answer your question, UV4L supports both MJPEG video up to 1920x1080 and JPEG Stills up to 2592x1944. You were using MJPEG video (--encoding=mjpeg). Try to load the driver with the --encoding=jpeg command line option instead to get 2592x1944 pictures. There is also a new plugin for the driver named uv4l-server which provides a web interface to set image ...


2

First of all, every UV4L option documented in the man pages can be passed via both command line and configuration file. If the UV4L Web Server running on the Rpi3 cannot (easily) be reached in any way from the Internet for a simple p2p, your other option is to "push" (in one direction) the audio/video streams from the Rpi3 to a Janus Gateway deployed ...


2

How do I debug this? Does uv4l have any error logs? If so, what is the location of them? Yes, by inspection of /etc/uv4l/uv4l-uvc.conf you have some options for this. To enable logging via port 514 for syslog, edit /etc/rsyslog.conf and uncomment these lines: module(load="imudp") input(type="imudp" port="514") Then run sudo systemctl restart rsyslog. ...


2

The correct commands to start an RTSP server on the Raspberry Pi are, for example: uv4l --driver raspicam --auto-video_nr --framerate 30 --extension-presence=0 cvlc v4l2c:///dev/video0:width=640:height=480:chroma=H264 --sout '#rtp{sdp=rtsp://:8554/}' --demux h264 Do not forget to pass --extension-presence=0 to uv4l. On the client side you can then play ...


2

In May 2016 Lattice Semiconductor published a guide (2:1 MIPI CSI-2 Image Sensor Aggregator Bridge Demo) for a Raspberry Pi dev kit used with the CrossLink Master Link board featuring a Lattice LIF-MD6000 device. There are instructions on page # 8 Chapter 4 (Hardware Setup), that describes the use of one Raspberry Pi's camera's oscillator to synchronize ...


2

What worked for me is as follows: I installed uv4l-webrtc-armv6 instead of uv4l-webrtc as given in the tutorial. Above step replaced uv4l-webrtc by uv4l-webrtc-armv6 which I could see by using command apt search uv4l-webrtc before and after installation. I tried changing option to --enable-webrtc to --enable-webrtc-armv6 but that threw errors. So I again ...


1

The author of U4VL is elusive and secretive. I suggest using the contact form on www.linux-projects.org to negotiate a contract for commercial use. The pseudonyms of the author on the Raspberry Pi StackExchange are "prinxis" and "RpiName" on raspberrypi.org - you can try to contact him/her that way too.


1

The raspicam driver is optional. That said, you are missing --auto-video_nr in your command line to create the /dev/video0 node expected by your program: sudo killall uv4l (in case some other instances are running, e.g. raspicam - however, this is optional, as multiple instances can run simultaneously) uv4l --driver raspidisp --display 0 --framerate 5 --...


1

uv4l is not yet supported on raspbian strectch (debian 9)


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At the end, I decided to put in place a reverse SSH tunnel and forward UV4L port to the public server. I forward the port using the following command: ssh -o StrictHostKeyChecking=no -Nf -R *:8080:localhost:8080 -i id_rsa user@server


1

SSH and UV4L both use port assignments for routing. Your university network admin is likely to have blocked those ports - most people don't need to SSH into things in the library, and unnecessarily open ports are bad for security. You should contact your university's IT department and ask what services are available on the public network.


1

I don't use a conf file; I just start it from a shell script. Although according to man u4vl they use the same options, in my experience it seems hard to get it them to work from the file (e.g., vflip alone causes an error at start; vflip=true does not, but is ignored) -- so I worry the ones that are harder to check, such as mem-lock, aren't necessarily ...


1

You can use v4l2-ctl in the V4L2 tools collection to set the frame rate to one allowed value.


1

p2p with rpi uv4l is not possible using browsers as browsers on rpi ( chromium and firefox ) cannot fetch the local media stream ( i don't know exactly why but i know they can't ) . So for inter-network scenarios (such as involving firewall and NAT ) instead of making a p2p connection go for centralized connection . Use a MCU on cloud such as janus and ...


1

Instead of using uv4l's raspicam driver to driver the raspberry pi camera, you can use the kernel-based bcm2835-v4l2 driver. Just modprobe it and enable it using raspi-config, and you should have a /dev/video0 file. After the device file appears, you can start uv4l with these options: uv4l --external-driver --device-name=video0 The text overlay will be ...


1

You can connect the Rapberry Pi to a GoPro via WiFi and get the live stream URL which would give you audio and video. You could then redirect that stream to something like YouTube Live so that it's accessible online. Note: this would require you to connect to your network via ethernet. KonradIT's goprowifihack repo is a great starting point to working with ...


1

13 may be more useful. After a couple of tweaks to use the UVC driver I found this to work with my USB webcam.


1

A webcam will most likely not work; they are usually made for Windows and the chances that it would be made for Linux are very low. I'd try to use the Pi camera because it was specifically designed for the Pi.


1

mjpg-streamer uses the kernel support for V4L2 (/dev/video0). You could probably stream to web with that or gstreamer, but it's understandable that uv4l is simpler to configure for web streaming. (uv4l automatically opens a page on port 8080 if uv4l-server is installed.) Troubleshooting via tools like v4l-ctl or guvcview would default to using /dev/video0, ...


1

You need to restart uv4l_uvc,not uv4l_raspicam, for USB webcams.


1

It was a DV webcam: apt-get install dvgrab dvgrab - | mplayer -j They may be modules to install or load too (e.g modprobe raw1394)


1

Simple mistake that I made was not connecting the device that I want to view the stream on to the same network as the Pi. Once I connected my Macbook and tablet to the same network, the streaming server worked perfectly.


1

There are several APIs available for direct camera interaction. In C you have a choice of the MMAL API, which is what the official demo apps (raspistill and raspivid) are based upon (their source code is a good intro to using MMAL), or OpenMAX. I've heard the latter is a bit harder to work with, but it is an open API while MMAL is defined by Broadcom. And ...


1

You can easily do it by using lsof (and UV4L): sudo lsof /dev/video0 The above command prints out some lines if and only if the camera is being accessed. Based on the presence of the output, you can easily write your script to turn on your leds via GPIOs. See the lsof manual to know how to run it in repeated mode for automatic, efficient polling every X ...


1

How easy this is depends on how raspivid works. I don't have my camera connected right now so I cannot check without digging into the source, but it is probably easier for you to just try my suggestion yourself. The camera does have a device node, probably /dev/video0 if there is only one camera connected. If raspivid uses this, lsof /dev/video0 should ...


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