Dear All,
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
Thanks in advance,
Paul
On Thu, Feb 04, 2021 at 07:09:03PM +0000, Paul Smith wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
You can use the v4l2loopback kernel module to create a virtual camera, and use one of the many tools to send video to the virtual video device. However, that will just send a video or image to the video device, it won't get your webcam's picture and overlay it on top of it. If you want that, you'll need to do what zoom is already trying to do, which requires a static background (a green screen).
On Thu, Feb 4, 2021 at 7:16 PM Jonathan Billings billings@negate.org wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
You can use the v4l2loopback kernel module to create a virtual camera, and use one of the many tools to send video to the virtual video device. However, that will just send a video or image to the video device, it won't get your webcam's picture and overlay it on top of it. If you want that, you'll need to do what zoom is already trying to do, which requires a static background (a green screen).
Thanks, Jonathan, for your clarification. I am now thinking about an alternative: blurring the background. Skype can do that, but not Zoom -- unfortunately.
Paul
On 2/4/21 11:09 AM, Paul Smith wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
Doesn't zoom provide that option already? You just need to have a reasonably clear background behind you.
There's an out-of-tree kernel module called v4l-loopback which you might be able to get to work.
On Thu, 2021-02-04 at 19:09 +0000, Paul Smith wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
If I google around, apparently there are things that can do the green screen effect with zoom without a *green* screen, though they may be Windows/Mac.
The point of using green screens is to have a uniform colour behind you that's very opposite of skin tone (blue or green being the most common, though the BBC had used yellow too) and from anything that you're wearing, that the keying device can detect as being background instead of foreground. You can research chromakey or CSO (colour separation overlay) for more info about it.
It doesn't have to be a screen. A suitably vivid colour bed sheet stretched tight will do the job. We've used fabric from a dressmakers, and blue cardboard pinned to the wall. But that's not always practical to do at home, and with people in lockdown they can't go out and buy things.
If you want to avoid the insides your home being shown on a webcam meeting, your simplest option is to hold the meeting somewhere else in your house that's less personal. Such as sitting in a position so that your loungeroom curtains are the only things visible behind you. I've seen journos working from home park themselves in front of their big screen TV and use that as the background.
On Fri, 2021-02-05 at 14:21 +1030, Tim via users wrote:
On Thu, 2021-02-04 at 19:09 +0000, Paul Smith wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
If I google around, apparently there are things that can do the green screen effect with zoom without a *green* screen, though they may be Windows/Mac.
The point of using green screens is to have a uniform colour behind you that's very opposite of skin tone (blue or green being the most common, though the BBC had used yellow too) and from anything that you're wearing, that the keying device can detect as being background instead of foreground. You can research chromakey or CSO (colour separation overlay) for more info about it.
It doesn't have to be a screen. A suitably vivid colour bed sheet stretched tight will do the job. We've used fabric from a dressmakers, and blue cardboard pinned to the wall. But that's not always practical to do at home, and with people in lockdown they can't go out and buy things.
If you want to avoid the insides your home being shown on a webcam meeting, your simplest option is to hold the meeting somewhere else in your house that's less personal. Such as sitting in a position so that your loungeroom curtains are the only things visible behind you. I've seen journos working from home park themselves in front of their big screen TV and use that as the background.
Just a few days ago the BBC had a story about second-hand booksellers doing a nice trade in selling batches of serious-looking books that people could place strategically behind them :-)
(Apologies for going OT)
poc
Apparently, the Windows version of the Zoom client will happily do virtual backgrounds without the need for a green screen (providing your hardware meets the minimum requirements). But then if we were Windows users, we wouldn't be here would we?
Unfortunately, that facility is not available to Linux users and, last time I checked, I don't think it is planned - probably down to lack of demand / pressure.
Phil
On Fri, 5 Feb 2021 at 11:39, Patrick O'Callaghan pocallaghan@gmail.com wrote:
On Fri, 2021-02-05 at 14:21 +1030, Tim via users wrote:
On Thu, 2021-02-04 at 19:09 +0000, Paul Smith wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
If I google around, apparently there are things that can do the green screen effect with zoom without a *green* screen, though they may be Windows/Mac.
The point of using green screens is to have a uniform colour behind you that's very opposite of skin tone (blue or green being the most common, though the BBC had used yellow too) and from anything that you're wearing, that the keying device can detect as being background instead of foreground. You can research chromakey or CSO (colour separation overlay) for more info about it.
It doesn't have to be a screen. A suitably vivid colour bed sheet stretched tight will do the job. We've used fabric from a dressmakers, and blue cardboard pinned to the wall. But that's not always practical to do at home, and with people in lockdown they can't go out and buy things.
If you want to avoid the insides your home being shown on a webcam meeting, your simplest option is to hold the meeting somewhere else in your house that's less personal. Such as sitting in a position so that your loungeroom curtains are the only things visible behind you. I've seen journos working from home park themselves in front of their big screen TV and use that as the background.
Just a few days ago the BBC had a story about second-hand booksellers doing a nice trade in selling batches of serious-looking books that people could place strategically behind them :-)
(Apologies for going OT)
poc _______________________________________________ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-leave@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org
On Thu, 2021-02-04 at 19:09 +0000, Paul Smith wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have.
Are you sure it's required? My quick look at the zoom help page just says that a solid colour background is required, green is preferred. You can choose another colour, if it can't work it out.
By "solid colour" it just wants a uniform flat colour of some description behind you, not a complex image. Coloured walls, curtains pulled straight, even a plain bedsheet can be used.
On Fri, Feb 5, 2021 at 3:32 PM Tim via users users@lists.fedoraproject.org wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have.
Are you sure it's required? My quick look at the zoom help page just says that a solid colour background is required, green is preferred. You can choose another colour, if it can't work it out.
By "solid colour" it just wants a uniform flat colour of some description behind you, not a complex image. Coloured walls, curtains pulled straight, even a plain bedsheet can be used.
Thanks to you all for your answers!
Probably, I will choose Skype instead of Zoom, as Skype on Linux can blur the background on the webcam video. Surprisingly, Teams (of Microsoft as well as Skype) cannot blur that on Linux!
Paul
On Thu, Feb 4, 2021 at 8:51 PM Tim via users users@lists.fedoraproject.org wrote:
If I google around, apparently there are things that can do the green screen effect with zoom without a *green* screen, though they may be Windows/Mac.
I looked into this with Zoom, because I wanted to have a nice background like my online bridge partner does. It turns out that Zoom does have a way to separate foreground from background that does not rely on a green screen. It mostly works although there are a few artifacts. However, this feature is only available on Windows. If you are running it on Linux, you need a green screen in order to use a virtual background.
I use an old slide projector screen with a green cloth draped over it. It works well but is a pain to set up for every Zoom call.
--Greg
On 2/5/21 7:49 AM, Phil Edwards wrote:
Apparently, the Windows version of the Zoom client will happily do virtual backgrounds without the need for a green screen (providing your hardware meets the minimum requirements). But then if we were Windows users, we wouldn't be here would we?
Unfortunately, that facility is not available to Linux users and, last time I checked, I don't think it is planned - probably down to lack of demand / pressure.
Phil
SOMETHING does virtual background in Linux. Maybe it's skype. I haven't actually used either facility, but when I was
playing around with the installations, I ran into the virtual background by accident. --doug
On Fri, 5 Feb 2021 at 11:39, Patrick O'Callaghan <pocallaghan@gmail.com mailto:pocallaghan@gmail.com> wrote:
On Fri, 2021-02-05 at 14:21 +1030, Tim via users wrote: > On Thu, 2021-02-04 at 19:09 +0000, Paul Smith wrote: > > I would like to replace the background behind in my webcam video feed > > with an image. However, that is not possible, as it requires a “green > > screen”, which I do not have. So, my idea is to use a virtual camera > > with a background image chosen by me and feed that into Zoom. Is that > > possible on Fedora? > > If I google around, apparently there are things that can do the green > screen effect with zoom without a *green* screen, though they may be > Windows/Mac. > > The point of using green screens is to have a uniform colour behind you > that's very opposite of skin tone (blue or green being the most common, > though the BBC had used yellow too) and from anything that you're > wearing, that the keying device can detect as being background instead > of foreground. You can research chromakey or CSO (colour separation > overlay) for more info about it. > > It doesn't have to be a screen. A suitably vivid colour bed sheet > stretched tight will do the job. We've used fabric from a dressmakers, > and blue cardboard pinned to the wall. But that's not always practical > to do at home, and with people in lockdown they can't go out and buy > things. > > If you want to avoid the insides your home being shown on a webcam > meeting, your simplest option is to hold the meeting somewhere else in > your house that's less personal. Such as sitting in a position so that > your loungeroom curtains are the only things visible behind you. I've > seen journos working from home park themselves in front of their big > screen TV and use that as the background. Just a few days ago the BBC had a story about second-hand booksellers doing a nice trade in selling batches of serious-looking books that people could place strategically behind them :-) (Apologies for going OT) poc _______________________________________________ users mailing list -- users@lists.fedoraproject.org <mailto:users@lists.fedoraproject.org> To unsubscribe send an email to users-leave@lists.fedoraproject.org <mailto:users-leave@lists.fedoraproject.org> Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ <https://docs.fedoraproject.org/en-US/project/code-of-conduct/> List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines <https://fedoraproject.org/wiki/Mailing_list_guidelines> List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org <https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org>
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On Fri, 2021-02-05 at 08:50 -0700, Greg Woods wrote:
I looked into this with Zoom, because I wanted to have a nice background like my online bridge partner does. It turns out that Zoom does have a way to separate foreground from background that does not rely on a green screen. It mostly works although there are a few artifacts. However, this feature is only available on Windows. If you are running it on Linux, you need a green screen in order to use a virtual background.
I just used Zoom for the first time, this morning. I had a ferret around, but although I can see an option in meeting (advanced) settings to enable it, I saw nothing else anywhere to actually make use of it. This is using their system through a web browser (Firefox).
I use an old slide projector screen with a green cloth draped over it. It works well but is a pain to set up for every Zoom call.
The practical aspects of it are a big problem.
For many people, they've re-purposed a small bedroom as an office, and there isn't room to set up extra equipment. Your best bet is hanging something from a picture hook, or leaning something up against a wall. You can get green & blue screens that have a springy outer border that folds over itself like a car windscreen sun blocker, when you want to pack it away. They can stand up by themselves against a wall without using any framework. They even make ones that hang off the back of your office chair, turning it into a big throne. Though being that close to it will probably have shadow problems.
The alternative is how we used to show slides and home movies without a real screen. Hang a cloth over the curtains. Turn the end around a broomstick, or spare curtain rod, a few times. Bulldog clip or clothes peg it to the rod. Pop the rod over the top of your hanging curtains to hold it in place.
On Sat, 2021-02-06 at 11:49 +1030, Tim via users wrote:
I just used Zoom for the first time, this morning. I had a ferret around, but although I can see an option in meeting (advanced) settings to enable it, I saw nothing else anywhere to actually make use of it. This is using their system through a web browser (Firefox).
Supplemental: I just downloaded their desktop application (RPM file on CentOS, so Fedora's probably more advanced). In there there's a virtual background configuration option, and the background colour is selectable (you click on the background in the preview from your webcam video).
Currently, I'm in a room with pale yellow/cream walls and it's sort of working, mistaking some skin tone. If I was in a room with different coloured walls it'd work better. I do have green walls in a room with a Fedora installation, so I'll try that out shortly.
So, a green "screen" isn't required. But you really want a flat coloured wall behind you. I work in video production, and for those unfamiliar with chromakeying, or colour separation overlay (CSO), bold primary or secondary colours are best (red, green, blue, yellow, cyan, magenta), and you're better using colours opposite to skin tone (green, blue, cyan being the most opposite).
On Sat, Feb 6, 2021 at 1:51 AM Tim via users users@lists.fedoraproject.org wrote:
I just used Zoom for the first time, this morning. I had a ferret around, but although I can see an option in meeting (advanced) settings to enable it, I saw nothing else anywhere to actually make use of it. This is using their system through a web browser (Firefox).
Supplemental: I just downloaded their desktop application (RPM file on CentOS, so Fedora's probably more advanced). In there there's a virtual background configuration option, and the background colour is selectable (you click on the background in the preview from your webcam video).
Currently, I'm in a room with pale yellow/cream walls and it's sort of working, mistaking some skin tone. If I was in a room with different coloured walls it'd work better. I do have green walls in a room with a Fedora installation, so I'll try that out shortly.
So, a green "screen" isn't required. But you really want a flat coloured wall behind you. I work in video production, and for those unfamiliar with chromakeying, or colour separation overlay (CSO), bold primary or secondary colours are best (red, green, blue, yellow, cyan, magenta), and you're better using colours opposite to skin tone (green, blue, cyan being the most opposite).
Thank you all again for your answers. I have meanwhile found something that gives me some hope: Using OBS Studio as a virtual camera on Zoom with obs-StreamFX plugin on:
https://github.com/Xaymar/obs-StreamFX
Now, my difficulty is how to install obs-StreamFX.
Paul
On Sat, Feb 6, 2021 at 3:07 PM Paul Smith phhs80@gmail.com wrote:
Thank you all again for your answers. I have meanwhile found something that gives me some hope: Using OBS Studio as a virtual camera on Zoom with obs-StreamFX plugin on:
https://github.com/Xaymar/obs-StreamFX
Now, my difficulty is how to install obs-StreamFX.
Actually, obs-StreamFX works through a OBS Studio virtual camera after applying the obs-SteamFX blur effect.
To install obs-StreamFX on Fedora, just follow the instructions in the Installation Guide and choose the ubuntu zip file.
Paul
On Sat, 2021-02-06 at 15:07 +0000, Paul Smith wrote:
Thank you all again for your answers. I have meanwhile found something that gives me some hope: Using OBS Studio as a virtual camera on Zoom with obs-StreamFX plugin on:
You're welcome. I had a quick look at OBS, since I already have it installed, and couldn't see an obvious way to use it as a middle man. I didn't go looking for plugins, I forgot about that.
One thing about OBS, be careful when defining hot keys. It likes to always snaffle your keypresses, and can make it impossible to type in other things at the same time.
On 5/2/21 06:37, Paul Smith wrote:
On Thu, Feb 4, 2021 at 7:16 PM Jonathan Billings billings@negate.org wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
You can use the v4l2loopback kernel module to create a virtual camera, and use one of the many tools to send video to the virtual video device. However, that will just send a video or image to the video device, it won't get your webcam's picture and overlay it on top of it. If you want that, you'll need to do what zoom is already trying to do, which requires a static background (a green screen).
Thanks, Jonathan, for your clarification. I am now thinking about an alternative: blurring the background. Skype can do that, but not Zoom -- unfortunately.
Just one question, what do you mean by green screen? I use zoom on my work laptop in Windows 10 showing static and animated backgrounds behind the camera image so that people can't see anything in the room behind me, and I didn't think there was anything special in my zoom configuration.
regards, Steve
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On Tue, Feb 9, 2021 at 11:44 AM Stephen Morris samorris@netspace.net.au wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
You can use the v4l2loopback kernel module to create a virtual camera, and use one of the many tools to send video to the virtual video device. However, that will just send a video or image to the video device, it won't get your webcam's picture and overlay it on top of it. If you want that, you'll need to do what zoom is already trying to do, which requires a static background (a green screen).
Thanks, Jonathan, for your clarification. I am now thinking about an alternative: blurring the background. Skype can do that, but not Zoom -- unfortunately.
Just one question, what do you mean by green screen? I use zoom on my work laptop in Windows 10 showing static and animated backgrounds behind the camera image so that people can't see anything in the room behind me, and I didn't think there was anything special in my zoom configuration.
A picture is worth a thousand words, Steve:
https://gadgetstouse.com/wp-content/uploads/2020/09/Green-Screen.jpg
Paul
On Tue, 2021-02-09 at 22:44 +1100, Stephen Morris wrote:
Just one question, what do you mean by green screen? I use zoom on my work laptop in Windows 10 showing static and animated backgrounds behind the camera image so that people can't see anything in the room behind me, and I didn't think there was anything special in my zoom configuration.
There's a few ways a device could detect the foreground (you) from the background (everything else) and use an alternative background image:
Detect a particular colour (like a green or blue background).
Detect a particular level (like a bright white or black background).
Something like MPEG compression. Where any pixels that change due to movement are foreground, anything that stays static would be the background. That has the potential for some very trippy effects when it gets it wrong.
The same kind of thing could be done by storing a still image from the camera before you step in front of it, and always comparing it with the current live camera.
On 10Feb2021 14:17, Tim ignored_mailbox@yahoo.com.au wrote:
The same kind of thing could be done by storing a still image from the camera before you step in front of it, and always comparing it with the current live camera.
Zoom on my Mac seems to do this, but neater: no background required, seems to detect that I move and that my background is static. I'm surprised by how effective it is. - Cameron Simpson cs@cskk.id.au
On Wed, Feb 10, 2021 at 1:59 PM Cameron Simpson cs@cskk.id.au wrote:
On 10Feb2021 14:17, Tim ignored_mailbox@yahoo.com.au wrote:
The same kind of thing could be done by storing a still image from the camera before you step in front of it, and always comparing it with the current live camera.
Zoom on my Mac seems to do this, but neater: no background required, seems to detect that I move and that my background is static. I'm surprised by how effective it is. - Cameron Simpson cs@cskk.id.au
In my experience, there are some artifacts (someone earlier referred to it as "trippy effects") around the edge of the person's head. And in any case, this feature is not available in the Linux version of Zoom. I don't know whether any of the other suggestions made in this thread might work or not, but the only way I successfully got background image to work in Linux Zoom was to use a green screen behind me. And no trippy effects.
--Greg
On 9/2/21 23:16, Paul Smith wrote:
On Tue, Feb 9, 2021 at 11:44 AM Stephen Morris samorris@netspace.net.au wrote:
I would like to replace the background behind in my webcam video feed with an image. However, that is not possible, as it requires a “green screen”, which I do not have. So, my idea is to use a virtual camera with a background image chosen by me and feed that into Zoom. Is that possible on Fedora?
You can use the v4l2loopback kernel module to create a virtual camera, and use one of the many tools to send video to the virtual video device. However, that will just send a video or image to the video device, it won't get your webcam's picture and overlay it on top of it. If you want that, you'll need to do what zoom is already trying to do, which requires a static background (a green screen).
Thanks, Jonathan, for your clarification. I am now thinking about an alternative: blurring the background. Skype can do that, but not Zoom -- unfortunately.
Just one question, what do you mean by green screen? I use zoom on my work laptop in Windows 10 showing static and animated backgrounds behind the camera image so that people can't see anything in the room behind me, and I didn't think there was anything special in my zoom configuration.
A picture is worth a thousand words, Steve:
https://gadgetstouse.com/wp-content/uploads/2020/09/Green-Screen.jpg
Thanks Paul, now I understand. But what I don't understand is why you are going to those lengths. As I said we use zoom for work video conferencing and we all use static or animated images as backgrounds by selecting the background we want in zooms configuration, which then works fine. Why do you need to display something behind you to get it to display a background image?
regards, Steve
Paul _______________________________________________ users mailing list -- users@lists.fedoraproject.org To unsubscribe send an email to users-leave@lists.fedoraproject.org Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/users@lists.fedoraproject.org
On Mon, 2021-02-15 at 09:18 +1100, Stephen Morris wrote:
Why do you need to display something behind you to get it to display a background image?
You can look at my prior responses for an explanation about it.
The application needs some way to determine what's background or foreground, to decide which imagery to transmit, and which to replace with something else. Using a solid colour background is a simple method.
-
Cameron Simpson -
Doug McGarrett -
Greg Woods -
Jonathan Billings -
Patrick O'Callaghan -
Paul Smith -
Phil Edwards -
Samuel Sieb -
Stephen Morris -
Tim