Video Capture Device (v4l2) plugin

ZeroLabs

ZeroLabs

Member
Okay... from the stackoverflow link, this gets me to where I need to be.
Code: 
sudo rmmod uvcvideo
sudo modprobe uvcvideo quirks=128
This will be reset every reboot. Because this works, with sudo mousepad I created the following file:
/etc/modprobe.d/uvcvideo.conf containing the line: options uvcvideo quirks=128

I now have two, count'em TWO webcams streaming simultaneously picture in picture from my Asus 1215n netbook! Wooo Hooooo!
 
L

leonhard

Developer
ZeroFossilFuel said:
Which brings me to the question how can I get my Logitec C270 to use MJPEG instead of YUYV?
Click to expand...

Try using one of the Pixelformats marked as "Emulated". Those should be native MJPEG in most cases with the v4l2 userspace library converting them to something obs can handle.
 
ubuntuaddicted

ubuntuaddicted

Member
any dev interested in getting the the hd-pvr 1212 working with this plugin? sadly it's only component 720p but there's no much out there for us linux users who want to capture external sources.

I have some more info. attempting to use VLC here's some info
hdpvr-1212_1.png

hdpvr-1212_2.png


but as you can see the video is black. i'm not sure why vlc can't display the video stream from the hdpvr 1212 because according to the mythtv wiki http://www.mythtv.org/wiki/Hauppauge_HD-PVR for hdpvr v4l2-ctl can interact with the device. when I just use cat /dev/videoX > video.ts and then atttempt to play the file back VLC returns this but does still play the file back.
Code: 
[0x210c118] main libvlc: Running vlc with the default interface. Use 'cvlc' to use vlc without interface.
[0x7f0840c01748] ts demux error: MPEG-4 descriptor not found
[0x7f0840ef0368] packetizer_mpeg4audio packetizer: AAC channels: 2 samplerate: 48000
Fontconfig warning: FcPattern object size does not accept value "0"
Fontconfig warning: FcPattern object size does not accept value "0"
Fontconfig warning: FcPattern object size does not accept value "0"
Fontconfig warning: FcPattern object size does not accept value "0"
[0x7f0824001248] main vout display error: Failed to resize display
let me know if you need anymore info.
 
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M

mangopuncher

New Member
Hey all, I've been using Windows to stream my speedruns and I'm frankly sick of Windows (I've been using Linux for most of my computing life). I'm glad to see OBS progressing as it is, but I'd like to investing a capture card that has a good chance of being supported when the time comes. I'm currently looking at Magewell XI USB 3.0. Link: http://www.amazon.com/Magewell-XI100DUSB-HDMI-Video-Capture-Dongle/dp/B00I16VQOY

According to the description from the company it has V4L2 support by default, which is pretty nifty. Is this capture card a good bet? I'd like to know your input. Thanks!
 
M

mangopuncher

New Member
For those of you wondering how well the Magewell XI100DUSB works, it works perfectly. Right out of the box with no issues so far in Ubuntu 14.04 if anyone is in the future looking to use OBS in linux for speedrunning.
 
ubuntuaddicted

ubuntuaddicted

Member
mangopuncher said:
For those of you wondering how well the Magewell XI100DUSB works, it works perfectly. Right out of the box with no issues so far in Ubuntu 14.04 if anyone is in the future looking to use OBS in linux for speedrunning.
Click to expand...
does it only do 1080p@30 FPS? Curious because my friend is about to buy the PCIe Avermedia capture card that does 1080p@60
 
M

mangopuncher

New Member
ubuntuaddicted said:
does it only do 1080p@30 FPS? Curious because my friend is about to buy the PCIe Avermedia capture card that does 1080p@60
Click to expand...

It will do 1080p@60fps just fine (important to me because the game I speedrun is locked at 60fps), the only drawback I can see is that like other professional grade capture cards it will require you to split the HDMI signal in order to play and capture at the same time, no big problem as those are easy to find cheap.
 
ZeroLabs

ZeroLabs

Member
mangopuncher said:
Hey all, I've been using Windows to stream my speedruns and I'm frankly sick of Windows (I've been using Linux for most of my computing life). I'm glad to see OBS progressing as it is, but I'd like to investing a capture card that has a good chance of being supported when the time comes. I'm currently looking at Magewell XI USB 3.0. Link: http://www.amazon.com/Magewell-XI100DUSB-HDMI-Video-Capture-Dongle/dp/B00I16VQOY

According to the description from the company it has V4L2 support by default, which is pretty nifty. Is this capture card a good bet? I'd like to know your input. Thanks!
Click to expand...
Holy crap! $300? Man I sure would like to see that come down.
 
lorddrachenblut

lorddrachenblut

Member
mangopuncher said:
Hey all, I've been using Windows to stream my speedruns and I'm frankly sick of Windows (I've been using Linux for most of my computing life). I'm glad to see OBS progressing as it is, but I'd like to investing a capture card that has a good chance of being supported when the time comes. I'm currently looking at Magewell XI USB 3.0. Link: http://www.amazon.com/Magewell-XI100DUSB-HDMI-Video-Capture-Dongle/dp/B00I16VQOY

According to the description from the company it has V4L2 support by default, which is pretty nifty. Is this capture card a good bet? I'd like to know your input. Thanks!
Click to expand...

One thing to keep in mind is that this device does not handle hdcp so you will want to track down a HDMI splitter that will strip hdcp
 
R

Radzaquiel

Member
I'm wondering...why can't OBS MP handle directly MJPEG with "V4L2_PIX_FMT_MJPEG" instead of going through emulated formats ?
Nowadays, many webcams (720p & +) uses internal MJPEG compression to keep a decent framerate with USB2 connection.

I managed to hack a little for OBS MP to recognize directly MJPEG but when I choose "MJPEG" then, it shows me a frozen pic or a messed one... =/
 
lorddrachenblut

lorddrachenblut

Member
Radzaquiel said:
I'm wondering...why can't OBS MP handle directly MJPEG with "V4L2_PIX_FMT_MJPEG" instead of going through emulated formats ?
Nowadays, many webcams (720p & +) uses internal MJPEG compression to keep a decent framerate with USB2 connection.

I managed to hack a little for OBS MP to recognize directly MJPEG but when I choose "MJPEG" then, it shows me a frozen pic or a messed one... =/
Click to expand...

I hope this is something you can get working. I'll be watching for news of this
 
R

Radzaquiel

Member
lorddrachenblut said:
I hope this is something you can get working. I'll be watching for news of this
Click to expand...
Well, given my pretty basic knowledge in C/C++, that's not sure I'll be able to finish this ^^'
For exemple, I must first understand why "Pixelformat" string seem inversed in output (VYUY instead of YUYV, GPJM instead of MJPG, etc...) & if it's normal...
 
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F

FireStarW

New Member
Here's some data for a dormant thread on some nameless logitech usb webcam I found at the thrift.
Edit: It's a C200 it looks like
(OBS 1.20.0)
Code: 
ioctl: VIDIOC_ENUM_FMT
   Index  : 0
   Type  : Video Capture
   Pixel Format: 'YUYV'
   Name  : YUYV 4:2:2

   Index  : 1
   Type  : Video Capture
   Pixel Format: 'MJPG' (compressed)
   Name  : Motion-JPEG
Edit: Just shows up as grey screen in OBS no matter the settings

Mplayer window capture works at least..
 
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T

Terry Knight

New Member
Logitec C170 webcam not working on OBS 0.14.2 - at best I get one still image capture in OBS. Webcam works fine in V4L2 test, Cheese, VLC and Skype - but can't use these as alternate capture methods because they also freeze up when OBS is started.
(Camera worked fine in 0.13.x)

Code: 
v4l2-ctl --list-formats
ioctl: VIDIOC_ENUM_FMT
    Index       : 0
    Type        : Video Capture
    Pixel Format: 'YUYV'
    Name        : YUV 4:2:2 (YUYV)

    Index       : 1
    Type        : Video Capture
    Pixel Format: 'MJPG' (compressed)
    Name        : MJPEG
 
T

Terry Knight

New Member
ZeroFossilFuel said:
Have you tried YU12 or YV12 emulated formats?
Click to expand...
Yes, I've tried both emulations as well as the default - no difference.
I still have the issue in the latest version 0.15.4. Ironically, everything was fine in 0.13.x - it's only since OBS went to 0.14.x and higher that this issue occured.
 
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