Talk:Chroma key

message: redundant mention of weather map applications in intro paragraph and within article - Johnjosephbachir 01:24, 5 Dec 2004 (UTC)
replies: text: I agree. I don't have time to deal with it now, but I added a cleanup tag. cluth 08:25, 5 February 2006 (UTC)
thread_title: Untitled

message: The statement "Prior to the introduction of digital compositing, the process was a complex and time consuming one known as 'travelling matte'" does not appear to be completely accurate, however I need some help from someone with more expertise. By at least the 60s (maybe earlier) live TV shows used green screens (chroma key) in real-time, apparently using purely electronic video techniques, which I can imagine has something to do with detecting the part of the signal electronically that is the key color and merging a diff video signal into that part. It did not need ANY digital process, but was definitely not time-consuming or overly-complex for the operators of the live TV production (at least not any more complex than anything else production staff do real-time).
In summary, there are three assertions which are an issue in the above referenced statement...
1. Complexity: The context here, complex would be relative other editing technique. It was not complex as it was performed real-time by a live production crew on many shows on a regular basis at least by the 60s.
2. Digital composting:  was not the first non-complex technique. (See above statement). This video chroma key was certainly was NOT digital composing (that should go without saying, the RAM required would have taken up a few buildings, ignoring the processing problem). It was a purely analogue electric signaling process.
3. Time Consuming: this is wrong in that Video based Chroma-key was around before digital, and the video technique not time-consuming at all... it was done in real time to a live audience.
Please editors let me know if you disagree or if you think I'm off my rocker. I shall revisit this article to clarify History at a later time. It will be tedious and take me a long time to create such content as I'm non-technical. Hopefully someone else jumps the gun before me!--Retran (talk) 09:05, 20 March 2010 (UTC)
thread_title: fact check for the History

message: My knowledge (and limited research) shows that the term CSO is only used by the BBC, oither UK broadcasters use the term Chroma Keying (ITV for instance)
--Jmptdc 13:35, 20 July 2006 (UTC)
thread_title: CSO

message: The reasons for the inclusion of the tags will have to be discussed or they will be removed. --WikiCats 10:50, 20 September 2006 (UTC)
thread_title:  Tags 

message: I recall seeing a special on TV in the 80s on the making of the Muppet Show where Jim Henson and a (real) lion sat against a bluescreen appearing to be in a computer-generated room, and they switched back and forth between a composited and an actual view for demonstration. For further demonstration he put on a blue tie (which the background showed through). I think this was an excellent intro to the technology, especially for kids. I'd add a reference to the article, but can't remember enough details to cite it. I hope someone else might have better luck. Deco 17:12, 16 November 2006 (UTC)
thread_title:  Jim Henson demo 

message: Is the use of this technique limited to Australia, and if not why is this worthy of the article? The technique has been used in most broadcast news in most countries since the mid-late 90's. I'm removing this section. If anyone wants to add it back in with an explaination of WHY it is pertinant to the article please go ahead. 
The section removed read:
Use in Australia
National Nine News bulletins in Australia are always broadcast using the green effect background. At TCN-9, where the majority of national bulletins are broadcast, the same newsdesk is used for the morning news, afternoon news, the 6:00pm news and Nightline. Briefly in 2004, Seven News in Melbourne was broadcast with a shot of Melbourne in the background. This was used from August 2004 until mid-2005. Ten News in Adelaide is broadcast using the green effect background. The shot is of the Adelaide River with the Ten News logo in the middle. This version is actually broadcast in Melbourne to save on costs.
ASH1977LAW 15:39, 10 May 2007 (UTC)
replies: text: Though Use in Australia is certainly not needed as a section, there is one interesting implication here: the article as it exists today gives no specific reason that news teams like to use blue screen. I didn't realize it was because they like to have a bunch of different-looking news desks for different things.64.186.47.170 (talk) 07:22, 7 June 2016 (UTC)
thread_title:  Use in Australia - relevance? 

message: What does the link to "Federal Standard 1037C" have to do with chroma keying?
I think this link can be removed.
:"composite video" has nothing whatever to do with compositing. It is a form of video encoding in which   the luminance and both parts of chrominance information are combined in one signal (coded yellow on the familiar RCA jacks and plugs of home VCRs and TV sets). It should be removed. Jim Stinson 20:09, 31 July 2007 (UTC)
thread_title: see also

message: I removed this text from the "Even Lighting" section because it sounded like advertisement:
I ran a check on the IP that added the text, 81.187.36.194, and it's registered to "REFLEC-PLC", the same company as Reflecmedia, the company mentioned in the text...  Hmmmm... Interesting. Sbrools (talk . contribs) 17:21, 2 November 2007 (UTC)
replies: text: Good catch! --Ronz 18:57, 2 November 2007 (UTC)
thread_title:  Advertisement POV 

message: Cant Adobe flash do greenscreen by making a background movie clip and making another layer with a different movie clip? Shouldnt this be mentioned in the article?71.53.20.131 (talk) 00:21, 5 December 2007 (UTC)
replies: text: Flash can output files that include an alpha channel.  This is created by simply recognizing areas that have no objects on them - there is no need to make special layers or background clips.  One would not call this "Chroma Key" however, because the alpha channel has nothing to do with the color of any object, but is instead is rendered from the geometry of files.  A rendered alpha channel is invariably superior to chroma key, because you don't need to worry about color ranges or reduced resolution of color channels.  You can also have transparent objects in the flash file allowing the background video to show through. Algr (talk) 07:03, 5 September 2008 (UTC)
thread_title:  Adobe Flash 

message: :Image:Utv cso studio.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in this Wikipedia article constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.
Please go to the image description page and edit it to include a fair use rationale. Using one of the templates at Wikipedia:Fair use rationale guideline is an easy way to insure that your image is in compliance with Wikipedia policy, but remember that you must complete the template. Do not simply insert a blank template on an image page.
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BetacommandBot (talk) 05:13, 21 January 2008 (UTC)
thread_title: Fair use rationale for Image:Utv cso studio.jpg

message: The articles says, many times, "human skin", "human skin colour", "human skin pigments", as if only white people were humans (as the article asumes human skin is pinky). I think this point of view is too whitecentric and must be fixed. --87.223.41.137 (talk) 13:42, 11 January 2010 (UTC)
replies: text: While your concerns are noted, you are incorrect in assuming that the article is referring exclusively to Caucasian skin tones. I've added a reference that states "if the foreground is a person then blue or green backing color is recommended as these colors are not present in human flesh pigments. In fact, human skin color is 70% red for all people regardless of race.". I hope this helps to ease your concerns. --Ckatzchatspy 18:37, 11 January 2010 (UTC)
thread_title:  Racism 

message: This section needs some work.  The idea that a "program" processes the video on a pixel-by-pixel basis is naive.  Earlier, with analog video, this was done using fast video switches.  The two video sources had to be frame and line synchronous.  The chroma key colored areas were detected with a phase looked loop (PLL).   An example of an integrated circuit that could be used for this is the MC1378 by Motorola.  Digital video chroma key operation is not programmatic either.  A state machine, implemented in digital circuitry, is used.  Zen-in (talk) 16:14, 19 October 2009 (UTC)
replies: text: No, the intention is that the last term is a constant and that the red value is not used in the calculation.Spitzak (talk) 00:13, 23 February 2010 (UTC)
replies: text: Thanks Spitzak.  In the article itself, I have inserted an equality (=) . --Hroðulf (or Hrothulf) (Talk) 14:59, 1 March 2010 (UTC)

text: The math is that used by the Nuke "Keyer" operator, which was implemented by reverse-engineering the keyer in Discreet Logic's Flame in 1995. In both cases these keyers are quite obsolete and do not make acceptable (to modern standard) separations, but the math is simple enough to understand and copy into an arbitrary program.Spitzak (talk) 20:58, 23 February 2010 (UTC)
thread_title:  Programming 

message: The statement "Blue was used before digital keying became commonplace because it was necessary for the optical process" has some problems. It wasn't necessary because it was an "optical process", but the chroma key relied on masking chemically while developing film. And blue is one of the prim colors and the background change could be controlled chemically. This seems to be more accurately described as a chemical process, not an optical one (optical is too broad, yes it employs optics though so do digital). That's my non-technical understanding anyway. --Retran (talk) 09:30, 20 March 2010 (UTC)
replies: text: Some clarity on this point would be nice, yes. My impression is: 1) Blue was apparently favored before the digital processes. 2) A "chemical process" was not involved. I thought at first there was some special "blue screen" film, a high-contrast monochromatic film using some specific chemical. However, I think what's going on is that a colored filter was used with black and white film when creating the matte. 3) Blue has a shorter wavelength and so is capable of a more detailed, accurate matte than green. I don't know if this makes a practical difference, but it may have been part of the decision, and is probably what a source means if it says blue could be high contrast more easily or could be more accurate.64.186.47.170 (talk) 10:28, 5 June 2016 (UTC)
replies: text: After rereading the section I decided to delete the offending sentence. (As of today it read "Blue was preferred as a backdrop before digital keying became commonplace because of the existence of high contrast film that was sensitive only to the blue color.") It's making too strong a claim without a source, and the previous paragraph does a better job. Still, it would be nice to have sources verifying why exactly the blue color was popular; it seems like the technology for green screen basically existed. Another possible factor that comes to mind is the low luminosity of blue?64.186.47.170 (talk) 10:39, 5 June 2016 (UTC)
thread_title:  The process fact check 

message: "This technique is also used in the entertainment industry, the iconic theatre shots in Mystery Science Theater 3000, for example."
MST3K is the best example of this being used in the entertainment field?  —Preceding unsigned comment added by 76.185.84.11 (talk) 20:32, 22 June 2010 (UTC)
thread_title:  Really? 

message: Could a blue and green screen work on any video camera?  —Preceding unsigned comment added by 98.71.53.3 (talk) 03:18, 2 May 2011 (UTC)
replies: text: Yes, any color camera could work.  However, the quality of the result would vary widely depending on the nature of the camera.  The worst case would be if the blue screen image was being played back from something like SVHS or Hi8, as these formats reduce the chroma resolution to well below what NTSC can do.  A camera with component out would be much better than composite.  The digital formats all keep chroma resolution reasonably high, and HD is a big help too. Algr (talk) 17:52, 31 December 2013 (UTC)
thread_title:  What Video camera? 

message: The "Processing a green backdrop" section claims "Bright green has also become favored since a blue background may match a subject's eye color..." This is not cited, and does not appear to be factual.  It implies that a green backdrop cannot match a subject's eye colour, which denies the existence of green-eyed people. Albertanyone (talk) 06:17, 30 December 2013 (UTC)
replies: text: That seems unlikely.  No one naturally has eyes that have nearly as intense color as the blue or green screens used in chroma key.  Algr (talk) 17:52, 31 December 2013 (UTC)

text: This point is overlooked in another context. As I understand it, keying is based not only on the hue, but on its saturation. A person could wear a light-blue shirt or dress against a backdrop of the same hue, without it causing problems. WilliamSommerwerck (talk) 23:37, 22 June 2014 (UTC)
replies: text:   I think this oversight is a significant one. Mostly what I came to the article for was to learn a little more about issues like this; is keying based on hue alone? How much variation in hue is allowed? etc. 64.186.47.170 (talk) 08:11, 29 May 2016 (UTC)
thread_title: Green vs Blue and eye colour

message: I was looking for an article on Ultimatte. Wikipedia doesn't appear to have one.WilliamSommerwerck (talk) 23:42, 22 June 2014 (UTC)
thread_title: Ultimatte

message: "In analog color TV, color is represented by the phase of the chroma subcarrier relative to a reference oscillator. Chroma key is achieved by comparing the phase of the video to the phase corresponding to the preselected color. In-phase portions of the video are replaced by the alternate background video."
This isn't true. Chroma keying occurs using the primary-color signals, long before they're manipulated to produce the NTSC or PAL subcarrier. WilliamSommerwerck (talk) 16:43, 6 July 2015 (UTC)
thread_title: major error

message: I removed the following sentence from the "Background" section, end of 1st ¶:
"For example, in John Pizzarelli's song Birthday Emotions from the Sesame Street television series, painting backgrounds made by  Gerri Brioso are used as a live-action film sequence while the kids such as the Italian-American siblings are jumping through the air and celebrating one of their birthday parties."
There is no reference given and the example is not particularly clear, and too detailed. It's supposed to be an example of red backdrops being okay.
That paragraph could use work overall.
64.186.47.170 (talk) 07:47, 29 May 2016 (UTC)
thread_title:  "Background" section 

message: Why is there no mention in any of the articles of Arthur Widmer, the inventor of BlueScreen? Seems none of the articles are complete, and so to merge at present would seem unwise/premature Rgds - Trident13 17:04, 4 June 2006 (UTC)
thread_title: Arthur Widmer

message: I agree that Bluescreen should be merged into this article. --WikiCats 14:37, 6 September 2006 (UTC)
replies: text: Wait a minute: all these terms, in both film and video, relate to systems of compositing. That article needs work, though it's generally OK as far as it goes. Also, the static or traveling matte pre-digital film technology also used blue (or other color) background screens for compositing. I don't think we've yet found the top of the subject hierarchy here. Jim Stinson 03:35, 31 July 2007 (UTC)
thread_title:  Merge with [[Bluescreen]] 

message: I also agree that the article bluescreen should be merged into this, since bluescreen is a subset of chroma keying.
I am changing my vote on merging this article with bluescreen because Chroma key is about television and Bluescreen is about film. They should be separate but have references to each other. --WikiCats 10:50, 13 September 2006 (UTC)
replies: text: It seems that the proposed merge has not yet happened, so I would also like to go on record supporting a merge of Chromakey, Bluescreening, and Greenscreening.  IMHO, the merged article belongs under Chromakey.  Bluescreening and Greenscreening make sense as redirects to a merged article under Chromakey.  Bluescreening is not unique to film at all.  Chromakey with video does tend to use a green background instead of a blue one, but this is far from universal.  I've probably done very nearly as much compositing where I had to key out blue in video as I have with green.  The techniques and concepts are identical. Forkazoo 23:49, 26 July 2007 (UTC)
thread_title:  Merging bluescreen 

message: The use of blue screen (aka green screen and chroma key)in visual effects is included in the new article Compositing. Jim Stinson 22:58, 10 August 2007 (UTC)
thread_title:  New compositing article 

message: Why has Blue screen been redirected to the out-moded term Chroma Key? Merging is a good idea, but merging from one specific term to another specific term, instead of a more general categorical term only adds inaccuracy. Chroma Key is a video only process that has gone out of favor for the most part. It certainly isn't used by the film industry and most video production artists today. Motion Image Compositing (or something else) would be a much better general term. 
--StevenBradford 22:18, 8 September 2007 (UTC)
thread_title:  Horrible Merger 

message: There are several points where the article needs to take some care to be internally consistent with its terminology. I don't know enough to try and edit it all the way through. I realize there's no right answer on some of these, but consistency would be nice. Please feel free to edit my words beyond this point. Dranorter (talk) 15:57, 9 June 2016 (UTC)
replies: text: Bluescreen does seem to be used much more than Blue screen but think about it. Except for the color, Chroma Key using a Blue screen is exactly the same as Chroma key using a Green screen, right? So Bluescreen does not refer to something unique. Quite often people use terms without really thinking about them and you are trying to correct that and that is something I am likely to do but I think that Bluescreen requires more thought. Sam Tomato (talk) 01:26, 13 March 2019 (UTC)
thread_title:  Terminology 

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thread_title:  External links modified 

message: got a school presentation bout cinematics and special effect
I would really appreciate you help
thanks for your consideration 
contact me on orfeas987@gmail.com  — Preceding unsigned comment added by 79.129.13.129 (talk) 11:51, 4 November 2019 (UTC)
thread_title:  i need your help mates 

message: Should these terms be one word or two? --Khajidha (talk) 12:08, 11 February 2020 (UTC)
thread_title:  Blue screen, green screen vs bluescreen, greenscreen 

message: The section Predecessors should mention rear projection. A bit above on this talkpage, it seems somebody tried to argue against including rear projection by calling it "a form of compositing". But that's irrelevant as the function is largely the same: If you wanted to replace a background before the wide use of chroma keying (or as an alternative to it), you would often use rear projection. --46.93.152.142 (talk) 20:28, 25 May 2020 (UTC)
thread_title:  Rear projection