Chroma Key Green / Blue Screen

Chroma Keying

Chroma Keying is a process to create a transparent background from a specific existing background color. The most popular  background colors used are green and blue. This Technic is used in for both photo & video. In video production and live broadcast this is very popular and used widely all over the world for many purposes like reading the weather and now most popular in conjunction with Virtual Sets. The idea is to place the subject usually a person in front of the camera with a color background (usually green), we will say green in this case. Using special software like Finncast Studio live video streaming software can remove the green background completely and creating a transparent background. With all the green removed Place a new image or other video footage behind the transparent background and this will be the new background. This is very usefully for many purposes like weather reading, use in conjunction with virtual sets, advertisements and even special effects.

There are a number of factors to creating the perfect transparent background even using the best chroma keying software you will need to set the lighting correctly on the green background. Choosing a good quality green screen is also something to consider with no creases. Also popular is special green paint or chroma key paint which is also used in the video industry.

Clothing

Clothing is also a factor if using a green background and wearing green clothing this will be a problem and the green on the clothing will also become transparent. In cases where green clothing is going to be worn you should use a blue background and vice versa.

Even Lighting

The biggest challenge when setting up a green screen or blue screen is even lighting and the avoidance of shadow, because it is best to have as narrow a color range as possible being replaced. A shadow would present itself as a darker color to the camera and might not register for replacement. This can sometimes be seen in low-budget or live broadcasts where the errors cannot be manually repaired. The material being used affects the quality and ease of having it evenly lit. Materials which are shiny will be far less successful than those that are not. A shiny surface will have areas that reflect the lights making them appear pale, while other areas may be darkened. A matte surface will diffuse the reflected light and have a more even color range. In order to get the cleanest key from shooting greenscreen it is necessary to create a value difference between the subject and the greenscreen. In order to differentiate the subject from the screen, a two-stop difference can be used, either by making the greenscreen two stops higher than the subject, or vice versa.

Sometimes a shadow can be used to create a visual effect. Areas of the bluescreen or greenscreen with a shadow on them can be replaced with a darker version of the desired background video image, making it look like the person is casting a shadow on them. Any spill of the chroma key color will make the result look unnatural. A difference in the focal length of the lenses used can affect the success of chroma key.

 

What to avoid

  1. Shadows on your green screen do not stand to close to the screen
  2. Good lighting light the screen well and the subject
  3. Clothing, do not wear clothing the same color of the screen being used.
  4. Use a good chroma keying software link Finncast Studio live video streaming software
  5. If using a material green screen have as little creases in the screen as possible.

 

Video Switchers & Mixers

video switcher

Video Switching is where video inputs are switched usually by hardware known as a video switcher or a video mixer.
Video switchers traditionally were a big and heavy piece of hardware and have become more light weight over the years. The purpose of the switcher is to switch video inputs to an output usually known as the program output or program monitor. The program output is what is transmitted and or recorded or if you like, what the end user the viewer sees.
So, let’s step back a bit video inputs, let’s talk about them. Video inputs are a video capture card which receives the output from a visual device such as a video camera but it can also be anything that has a video signal like a computer, a television, a projector, a tablet and so on. As an example, a video cameras video signal is an output. We can put that output via some sort of cable connection into a video input of a switcher. The switcher will usually have a number of video inputs and it is the video inputs that we are actually switching to the program output.

Traditionally video switchers had a lot of additional hardware added to them is some sort of way to allow for video recording, broadcasting and even for playback footage. This meant a lot of hardware with many cables and much electrical power needed and required a lot of room to accommodate this hardware. This if you like became a video studio with hundreds of illuminated lights form all the different hardware, fans added to keep all the equipment cool.

Who uses video switchers? Well traditionally television stations broadcasting many live shows or even to produce pre-recorded show to broadcast at a later date. A typical talk show with have usually 3 set camera. Cameras 1,2&3 usually went from (1) left to (2) centre to (3) right.
Each of these cameras were connected to a video switcher with 3 camera people operating the cameras controlled by a Technical director and or by a person known as a switcher.

A Technical director.

technical director
The Technical director is usually reasonable the broadcast side of things not to be confused with the producer of a show. The Technical director is reasonable for the full audio and visual to be presented to the audience and for each piece of footage to be played and the switching of all cameras. Some Technical directors do the switching themselves and also give commands to the camera operators. Also, usually for more fast switching programs like live news a person known as the switcher operator will press all the physical buttons and line up the view to be switched. The switcher operator will take the commands to switch from the Technical director for example camera 1 “take” or “auto take” or “line up in preview” and so on.
The workload of switching the visuals can be quite fast moving almost like a pilot landing a plane trying to control the aircraft and deal with air traffic control is a very fast and time controlled procedure. So, if you like The Technical director is like the captain and the switcher operator is the co-pilot. Both have a key role to play.
So, what can the average switcher actually do when it comes to live broadcast?
As mentioned above switch all the video inputs and playback footage. Also, when switching there is the ability to switching using transitions.
Transitions or transition switching is where the switch between two visual can be made with some sort of smooth change like a fade, fading between the visuals usually fading one out and one in. In today’s choice of transitions built-in to the switcher there are many to choose from, with flying in and out transitions to blinds, circles and other shapes it can add that extra professional touch to the switch.

Most Switchers but not all! will has a Preview out as well as a Program Out. In traditional Switchers they were only physical outputs that could be connected to monitors for viewing by the Technical director and switcher operator.
The purpose of the preview out (only seen by operating staff) is the setup what will be switched to the program out, it can only be seeing by the operating staff and not by the audience. This is a very useful in know exactly what will be switched to the program out (which the audience will see). It prevents error of switching the wrong camera or playback footage. The Technical director will usually say something like hold camera1 or preview camer1 and the operator with select camera 1 with the preview buttons to be placed in the preview. When ready for the switch from the Preview to the live Program out the command will be either Take camera 1 or Auto Take camera 1.

The Take & Auto Take make the switched from the Preview to the Program out by buttons named Take and Auto Take. Some switchers will have a cut button instead of a Take button in such cases it is likely the verbal command would be cut camera 1 or whatever is to be switched.
The Take or Cut button will without delay and without any transition switch the preview to the program at the blink of any eye. The Auto button or Auto Take button will make the switch between the Preview and Program in a set time in seconds using a chosen transition. As an example, Camera 2 maybe presently in the Program out and now Camera 1 with be faded in over camera 2 in a pre-set time of 3 seconds.

Also used in the Switched process is the most popular Transition Bar.

The Transition bar is where the switch is made manually in a gradual movement by the switch operator using a handle or slider in software or both. The transition bar is used usually when making the switch using a transition like a fade. The Transition bar is different than the auto take button as the operator can stop anywhere in the process. This useful when fading two visuals giving a ghost effect.

Downstream using a switcher.
Not all switcher has the functionality to downstream but for those that do, the downstream options will vary. Downstream options are much more choice in Software video broadcasting programs like Finncast Studio www.finncast.com than those in an only physical switcher.
What exactly is down streaming? Down streaming is where a visual whether it is a camera or an image a chart a piece of video footage is overlaid on the program out. Overlaid meaning placed on top of the existing visual. Unlike the switch which will replace the existing visual with a new one a downstream will be placed over the existing visual with a defined width, height, and position usually setting x position (from the left of the screen moving horizontally) and y position (from the top position moving down vertically). A typical example of a downstream would be a shopping program with a text downstream of a phone number placed on the screen. The most used downstream is logo for the broadcasting company like a Television station. Using the logo as an example of an image being down streamed (overlaid) switching will still take place as normal with the logo remaining on screen. Any video input can be switched (which is technically behind the downstream ) Down streaming is an almost a must for broadcasting especially since online broadcasting is now done by almost anyone who wants to live stream or broadcast professional looking footage.

 

Effects can also be found in Switchers like old movie, Monochrome, Split screen and so on. Such effects are popular in the making of pop videos.

Audio control.

Most switcher will have some form of audio control or even a built-in audio mixer. The Video switcher may also work in conjunction with a separate audio mixer but the video mixer will at a minimum except the audio output from an audio mixer into the audio input of the video switcher. With that said let us talk about video and Audio inputs and outputs.

Inputs and Outputs

For some inexperienced users starting their hand into the video production world, inputs and outputs can become somewhat confusing and even complicated. So what is a video output? It is a video signal from a device like a camera or as an example let us talk about a desktop computer as most of us will have used one at some stage in our lives.

A desktop computer is usually separated from its monitor and connected via a cable. The desktop computer will have a video card installed which will have a video output or maybe more than one output. Some video cards will have a VGA output and a HDMI output. Whichever, it will have the video signal from the video card. The Monitor used to view this video signal will have a video input again usually of either VGA or HDMI or both. So, the video output transmits the video signal and the video input receives it. The video output is always connected to the video input or at least think of it that way. Output what is to be viewed to input what lets me view it.

The process takes place of course will have to encode and decode the video signal but here I just want to explain inputs and outputs from a connection point of view. And yes, there is formatting and codecs etc but we are only going to focus on the connection of such hardware. Many people asked us is it possible to connect a computer to the inputs in Finncast studio? Yes of course is the answer. The users video capture card might have SDI video input connections and their desktop computer HDMI output. Needless to say HDMI will not physically fit into a SDI input, and this is still possible as there are many video converters some of only cable to carry out this process. Input & Output connections may not be of the same connection type but using specific cables or converters makes this very much possible.

Audio Outputs & Inputs work on a similar principle as video just with audio only. As a quick example the microphone outputs the audio to an input of a sound card and the sound cards outputs the audio to the inputs of the speakers or headphones.

Software’s for broadcasting and Switching such as Finncast  Studio hugely eliminate so much of the hardware traditional required. Such software’s have built-in video switching with down streaming, video playback (no need for playback players), Chroma keying for green screen, Lower thirds and even Virtual Sets / Studios. They even have the ability to record without any physical recorder and live streaming over the internet.  And it is now video production is at a high with YouTube uploads and live streams and so many people now being not camera shy video broadcasting is all around us online and very one is at it.

Virtual Sets

virtual sets

Virtual Sets also known as Virtual Studios are largely used in video production and live broadcasting.

For this article we will refer to them as Virtual Sets. So, what exactly is a virtual set and why use one? A virtual set is where we can create a live broadcast or previously recorded show on a set that is virtual. A virtual set can be of an image or a video. The most commonly virtual set is an image.  A Virtual set is used in conjunction with chroma keying usually with a green screen.

chroma key green screen

The image of the virtual set is the background image where more images can be added, text, and the video cameras where you can place the host of the show and even guests on to the virtual set but in reality, they are just sitting at a green screen. A broadcasting or video editing software is required to setup the virtual set such software’s like Finncast  Studio live video streaming software. Some software’s require a special set image with masks to add virtual screens to the set. A virtual screen is a monitor(screen) as part of the set image and the screen can show footage and images. However, using Finncast Studio no screens need to be part of the virtual set image as Finncast have created what they call Virtual screens which can be added anywhere on the virtual set at the click of a button. These virtual screens are very powerful, they can be resized and placed anywhere on the virtual set with a drag & move of a mouse and they have full axis movement for complete 3D display. The virtual screens will play video footage, show images, live cameras and other video input devices. This really adds to the virtual set giving even more a reality effect.

Choosing which software to use for your virtual sets is really down to your budget, how often you will broadcast and how professional you want to be when broadcasting.

Real studio sets are very expensive to setup and require large space in a building for the studio.  Where in reality using a virtual set could be done in your bedroom. Virtual sets are not just of studio type they are of schools and churches and halls etc. It is an image background where you place yourself the subject on the set and produce a very professional show.

With high speed broadband, powerful processor computers and graphic cards that have their own processors and memory online broadcasting is enormous. There are so many live streaming web-sites to choose from like YouTube, Facebook, Twitch and many more, broadcasting live is just plain simple.

Many people are making big money with successful views on YouTube and the more professional your videos are the more likely you will get more viewers.  With successful videos like AMSR, a makeover tutorial, a review on technology, how to lose weight and so on, using a virtual set with your production is most certainly going to bring a bigger audience.

Imagine this Mary does a makeover video in her bedroom with a banner of a makeup product stuck to the wall behind her. She had to pay for the banner to be printed or begged the product manufacture to send her one for her YouTube video on how to apply eye shadow. The banner eventually arrives and she has to phone 4 of her friends to come over to help her put it up.

So, what is the viewer looking at, is Mary in her well cleaned bedroom with a big banner on the wall saying Product Name. Now picture this, Mary is using Finncast Studio with a cool modern virtual set with images of the Product Name on the virtual screens in her studio. As the video starts Mary’s name slides across the screen on a Lower Third and then off the screen and Mary says welcome to my show.

In today’s world Mary does not need to book herself into a recording studio to produce a professional video production or live broadcast with the thanks to software’s like Finncast Studio and the use of virtual sets. Time, technology and people being so less shy of the camera is now the time to broadcast to the world.

Many people ask me so how do I get started? What do I need?

1: A computer, recommended a quad core processor say 2 Ghz or greater with a good video card.

2: A camera, it can be a Full HD web cam or an external camera connected to a video capture card.

3: A software for video production and live broadcasting like Finncast Studio.

5: At least one virtual set image.

6: High speed internet connection.

7: And of course you the host of the show.

Virtual Set images and videos can be purchased on many web-sites on the internet which specialize in this area. Also, you can hire a graphic designer to make you a virtual set, the advantages of this is the set will be unique to you or better again if you are a graphic designer. Some virtual sets are a video which loops the play back over and over. They can look very good but my own preference is a static image of a set because it uses little or no processing power of the computer and I can add much more to the set like images of a podium, a desk, logos etc. this is a major advantage!. What I am saying here is you can have a very basic image of the set and build on that by adding additional images.

I would suggest that the virtual set image be a minimum size of 1920×1080 which is full HD. However, if it was smaller Finncast Studio will auto scale the image up.

Now I must mention with Finncast  Studio live video streaming software you can pan and zoom on the virtual set this is just incredible to see. it will simulate a camera operator zooming in on the subject even though there is no camera operator. What I mean is you can place your camera on a tripod, sit at your green screen remove the green with the chroma key add your virtual set and click the mouse on the set to where you want to pan and zoom, you will also be able to set the speed and distance of the zoom.

 

So, my final words on virtual sets is, if you are starting any sort of video broadcasting or video production shows as your business or hobby or just to make an income virtual sets should be used and if you hit the success you have dreamed, of making lots of money, then you can bring your show into a real studio.  Consider it like starting a courier delivery business, it would make more sense in the first year to hire a van than buy one. If your business did not become profit making closing is simple just stop hiring a van and close the doors, but to be stuck with a purchased van would make no sense and you may lose so much on the sale of the van. As equally renting a building paying to setup a studio makes no sense until your show is a success. And of course, on the solo broadcaster side of things a virtual set is definitely the way to go.