An Experimental Infra-red Chroma-Key Camera
ฝัง
- เผยแพร่เมื่อ 26 มิ.ย. 2024
- I decided to build a really low cost chroma-key camera unit to test out this idea. I am using infrared (850nm) to act as the color that the system uses to identify the background. This eliminates a number of problems but also creates a few new ones...
Some people might not appreciate the text-to-voice tool that I use, unfortunately it is a necessity, I currently live in mainland China, so a degree of anonymity is helpful and in addition to that I have a natural voice that is "perfect for print". I would love to be able to hire a voice talent like Simon Whistler, but I somehow doubt he is interested in an unpaid job like narrating for my little channel.
Davinci Resolve Download.
www.blackmagicdesign.com/even...
OBS Studio Download.
obsproject.com/
Corridor Crew Video.
• This Invention Made Di...
3D Optix.
simulation.3doptix.com/
Taobao link to the crappy webcam.
m.tb.cn/h.gWtPa26DYzgvcJX?tk=...
Taobao link to the beam-splitter plate.
m.tb.cn/h.gWtlhgLwDGZ3WDg?tk=...
Taobao link to the short-pass filter.
m.tb.cn/h.g3nQQNatGNcT92I?tk=...
Taobao link to the IR band-pass filter.
m.tb.cn/h.g3eht0DRq8G7M1I?tk=...
Link to bambu Lab, I used the P1S to make the parts for this project.
store.bambulab.com/products/p1s
00:00 Introduction
01:54 History
04:10 Concept
08:30 The Build
11:04 Testing
13:08 Lessons
16:18 Closeout
#greenscreen ,#chromakey ,#chromakeyvideo ,#videoediting ,#filmmaking ,#optical, #optics,#bambulab ,#davinciresolve ,#obsstudio ,#3doptix - วิทยาศาสตร์และเทคโนโลยี
You're on track to being another 0.5mil+ cool/entertaining/educational/interesting techsphere/maker youtuber, the content, production quality and distinct/enjoyable narration are there, now all you need is exposure - something you won't really get without bending over for the algorithm which by all accounts is below you. Please keep making/thinking of cool shit and sharing it with us little international people, you're great at it, thanks a bunch!
comments like this make it all worthwhile. Feeding the algo is interesting, but generally needs a channel to become a MrBeast clone, which is not really my thing.
Frankly, I never imagined I would ever see 1K subs, so things are a little hard to keep track of...
Very good! Impressive result! You do not ever disappoint and I always learn a lot every time!. So I hope there's still a lot in the pipeline,
OMG, you called me a "TH-camr", I have never thought of myself of having any titles beyond Husband, Father and Engineer...
As for bending over for the algo, It's not a question of being unwilling, but more a case of genuinely being not sure what that involves.
Sodium vapor process isn't CHROMA keying, it's just keying. It recorded a separate film strip with just the key. Chroma key was later invented so that you could film on one strip with regular light, and later extract the key by filtering chromaticity.
That's a very interesting point, thanks for the feedback! So what I should have called this video is IR-KEYING with chroma.
Its the comments that I love about making videos, there are always smart people to help me learn too!
An approach I remember seeing on a comercial product a long time ago was to use a retro-reflective material as the screen, and mount the IR light source very close to the camera; this way the you can use a much dimmer IR source and still get a very strong contrast as most of the light emitted is bounced back towards the camera, but only by the retroreflective screen as most normal surfaces will bounce in all directions spreading it around and significantly reducing how much IR comes back from them.
Love the new logo and name
12:03 Ahhhhh. Ha ha.
Here's a fun fact: Most consumer cameras don't have a frame rate. A lot of people are surprised by this when they capture video on an iPhone and use old PC software to edit it. The camera automatically spends more time per frame when there's low light and less time per frame when there's action. Every frame has an accurate timestamp. Video players handle this gracefully and just show frames when it's the right time instead of matching video fps with monitor Hz. Your compositing software should do the same. I've been binging your channel for a couple of hours and I'm glad I finally have something to contribute :)
very interesting, thanks for the feedback!
Great stuff!
Thanks!
Great work! You have a lot of energy to pursue these projects, nicely pruduced video also.
Thank you very much!
Corridor Crew, Steve Mould, Project326..... I'm afraid this is the maximum amount of sodium vapor light videos I can medically handle in one month. lol
If I squint hard enough, I am almost able to convince myself that the spectrometer is actually able to partially resolve the D line doublet. If that is the case I am even more eager to order it than before, regardless of the fact that the grating is transmissive and so the spectrum cuts off at UVA and lower wavelengths. I will still have use for it in the visible and IR!
You missed Brainiac75, he just released a sodium lamp video too.
If those guys start making vids about IR chroma-key, I'm gonna go ballistic in the comments...
lol! we are watching the same vids! ... changing your channel name from "Studio" to "Project" ?
@@Neptunium yes, I have been meaning to change it for a long time...
I noticed a couple of sodium lamp vids have appeared after my spectrometer one - it will be interesting to see if anyone tries to re-do this project...
There are quartz gratings that go down to UVC at 200nm.
@colinbm2010 but cheap ones though? I see them on edmunds for several hundred. None on the forbidden site that shall not be named lest the comment get instadeleted.
Super interesting video! :)
Glad you think so!
When I saw Mary Poppins as a kid I was like "look at that weird old lady" now as an adult it's more of a "damn Poppins is hot, would!"
yeah, WOULD is the right term, Julie Andrews was actually a HOTTIE at that time, I just never noticed...
God, I hated this movie until I made this video. At Christmas it was always Mary Poppins or Chitty Chitty Bang Bang as the main feature on the BBC when I was a kid.
pretty fine, for a meat-bag.
This was AWESOME! I think this concept of using backlit, narrow band, non-visible light for chroma is incredibly interesting! I had sort of thought of maybe using a pure white screen and washing it in blue or green LED light to make a bright background, but your idea is way better.
Have you seen how modern LCD screen LED backlights work? With the edge lit acrylic that has a pattern of dots etched in to produce a nice, even light across the panel? I think they also use fresnel lenses to make the light a little more directional? I could imagine something like that, used as a thin, rigid board or sheet to backlight in pure IR.
You got my imagination running!
I have actually just dissembled a large edge lit backlight from a damaged advertising display, ready to do exactly what you suggested,
@@project-326 That's very exciting! I do wonder if the clear plastic used for those is transparent to IR. 🤔
Come to think about it... I suppose polyethylene and polypropylene might also work since they're transparent to IR... Sort of weird to think about a visibly opaque plastic sheet actually being bright in IR..
You know what would be even better? Using a TOF (time-of-flight) sensor to create a depth map and then you don't even need any kind of background. You just use a threshold effect on the depth map to extract the key for a certain depth.
an interesting idea...
The problem would be the resolution of depth map. If you using IR dot, then there is a limit of angular size of the object. The limit is the space / angular distance between each dot.
Or maybe you could use full coverage IR and calculate the ToF for each pixel. But idk if developing the program would be a nightmare or not.
@@trirahmat5384 spatial resolution is certianly going to be problematic. Most ToF systems use a dot projector with about 128x128 dots.
@@project-326 True, but combined with some clever processing, you could use the visible light image to upscale the depth map. My Huawei phone does a pretty good job at this, making a key to blur the background. Someone even made an app that shows the TOF depth map directly.
@@lit2021 My Xiaomi does too but it a 50 Mpx device...
For the infrared light I would propose VCSEL's; in short they are lasers and as such have a very narrow spectrum too.
In combination with a proper narrow band filter, you should get high contrast pictures.
But this also could have a downside: in frontal lighting scenarios you could experience specle.
Great idea, video and good introduction into your webcams, thanks for that! :D
impressive!! thnaks for this new experiment sir! this chanel is a gem!
So nice of you
I wonder if this should be referred to as a Thermokey?
It's only NIR, at the same wavelength that most remote controls work at. Thermal IR is normally considered to be at much longer wavelengths...
But it's a catchy name!
this is great! I had a very similar idea a week ago
Now do a video on the snow from the Wizard of Oz!
I'd love to, but I'd be sued by Disney in a heartbeat.
thank you very much for the movie and information. Sincerely, Antonio
My pleasure!
I'm new to your channel/videos. I don't like the voiceover much, but the humor you mix in makes it tolerable. Your English can't be THAT poor. :P Great content anyway. :)
I sincerely hope my English isn't THAT poor, I am native British!
I live in China, so a little anonymity (in the form of TTS) is helpful, but I also have a voice that is "perfect for print".
I am going to be experimenting with a real voice in the next few videos. The problem is that you just can't please everyone. Some people have gone out of their way to say that they like this voice as it is very clear. The viewers that are non-native English speakers in particular might be disappointed with the next few videos.
@@project-326 `voice that is "perfect for print".` Now that's funny. I guess we'll see. :)
Please create blue ray microscope pleeeease 🙏
Nice 👍
Maybe you do this already, but remove the vignetting before processing further.
You can shoot a grid and then do a manual alignment by matching the grids in both images. Could probably do a bit of warping to get a really good match.
And it would be interesting to see if the reflection problem can be solved by a polariztion filter.
I’m no expert but I wonder if you could just hack the cams so they receive the same record signal. Like hijacking the physical button press from one camera and feeding it to the other. Just solder the switch to both cams?
thanks for the tips with the post processing. The reflection issue is pretty easy to remove with hindsight, its a visible reflection and just adding 2 BPFs in series will probably remove it. These kinds of reflections are also a nightmare for traditional green screen too.
It a new technique, so a lot to learn!
6:58 "at about f-ck all frames per second"? whaat? 🤣🤣 is it a mistranslation of 操 ?
I believe that is the scientific term for the exact frame rate employed by these cameras.
@@project-326 lol
dude has audio lab but uses 2015 TTS... I can't even begin to comprehend
Hey, "posh Arthur" is pretty young. I don't want to upset him with calling him old - he might decide to retire!
;-)
Brilliant again! Any progress on making the spectrometer you featured recently available outside China?
Thanks, shame the video didn't really get any traction, it took a long time to make it all work, far longer than is obvious from the video...
I'm working on the spectrometer availability right now, I hope to have a video update on that in 2 to 3 weeks (this is just a hobby channel so needs to fit in with work and family).
Another great video,
It would of been interesting to try and get some semi-transparancy going with a veil or other items that they could do in Marry poppins, as that was considered another advantage of the sodium light technique.
Another thing to be aware of those webcams will vary frame rate due to low light. i.e. auto expose and just have a longer shutter time to collect light. Probably a losing battle, but some times brighter lights help (or may not).
I agree, I wanted to do that but with the crappy cameras, I was a bit restricted to an on-off type matte, ie fully saturated.
How about ultra violet keying? :D
That would be funny, give all the actors a suntan!
what is the reason for no shadow at infrared?
the shadow is made with visible light, not the IR background illumination, so the alpha matte doesn't see it...
@@project-326 thanks it makes more sense now since the clip is played from begin, as the new used algorithm if clicked on half of the link starts play from the half. Hope they do not introduce any updates, as it introduce mainly issues. It is very good ides to use non visible spectrum for background discrimination. It may be interesting if you use cheap cameras, to try how it responds to alpha and beta radiation as diode sensor, framerate standard at budget is 9 fps. just to add to discussion, it was unclear why offer 25 fps if 50 fps is available, but found that sensitivity at higher framerate is not sufficient so specially nigh captures appear dimmed at high framerate.
using raw or compressed raw would be best, as very lossy compression would fuck up the edges, also timecode too
these $hitty cameras don't encode a timecode into the video output...
2:22 That looks like a high pressure sodium bulb.
Indeed it is.
@@project-326 Aha But high pressure sodium lamps don't output the very narrow 590nm yellow wavelenghth. Only low pressure sodium does that.
@@Ni5ei After it warms up, the other lines are drown out by the intense 589nm double line. The spectrometer auto-ranges to the highest peaks. The spectral plot shown is what was measured from this HPS tube, I don't have any LPS tubes. HPS has the exact same sodium-D lines as LPS, at least once it is running and hot.
@@project-326 I'm curious to test that when I have the spectrometer. I have many street lighting lamps and will compare HPS to LPS. To the eye, HPS is a very different color than LPS.
is it possible to make the mask black, in post? Then a slight mist position looks less like a mess?^^
probably, but my editing skills aren't exactly "corridor crew" level. Having better cameras would have helped but I just don't have the budget...
Almost clicked off because of the TTS voice
I thought that for a split second but stayed because someone using old-school TTS instead of the soulless AI TTS is probably cool.
Yes, it's old school TTS - takes a lot of work to get it to sound even slightly realistic...
In the next video, I am going to be using a real voice as an experiment. I get the feeling I will see even more comments lamenting the absence of "posh Arthur"...
glad you didn't...
@@project-326 Clipchamp does have built in TTS generators but for the real experience, use an AI
Maybe it's an artistic choice, but the TTS just sounds so lifeless
it because I live in mainland China and anonymity is important to me and my family.
Wait what? I just watched one of those sodium vapor vids like a week ago!?
Any update on the spectrometer?
I'm working on it, but I might have to travel to Beijing to talk to the guy F2F.
@@project-326 👀 BIG
That's over 2000 km from where you live... @@project-326
@@project-326 Please do, I would like one too.