Tutorial
Blendy VJ acts like a bridge between two Syphon-enabled applications.
On one side is the input, an application playing or generating the graphics you will project, delivering a Syphon texture.
In the middle, Blendy adds a blend pattern next to your input and delivers another Syphon texture. This pattern will be used to hide the edges of each projector, by mapping it exactly where the light is doubled.
On the other side is the output, an application that will map your input and the blend pattern to the projectors.
Syphon is a framework based on a revolutionary technology called IOSurface, available only on Mac OS X 10.6 (and above), which allows graphic applications to share textures in the graphics card, with near to zero overhead.
The Setup
Place the projectors side by side, with at least 20% of their light overimposed. On this tutorial we’ll make a dual projector setup. But you can blend more projectors if needed.
Is is important that all projectors should be the same brand and model, and their lamps have the same age for a perfect blend. Otherwise, you may have difference in brightness and/or contrast between them.
PS: Vertical blend will come soon. But if you need it now, you can do it by mapping the blend textures horizontally. Read on and you will understand how.
You will obviously need a Matrox DualHead2Go, TrippleHead2Go or similar product to output to multiple projectors. If you need to buy one, go for the TrippleHead Digital Edition or DP Edition, it also works as a DualHead.
So plug it in, and for the sake of this tutorial, configure it as DualHead with 2048 x 768 output.
The Input
First of all, you need a Syphon-based player, like Modul8, CoGe, VDMX or GrandVj. There’s a lot of options on the Syphon website.
You can also develop your own application that outputs Syphon textures using Cinder, openFrameworks, Quartz Composer, PureData, Max, Processin, or any language you like. See the Syphon website for more info on how to do that.
To make Modul8 generate a Syphon texture, go to Modul8 > Preferences > Misc > Syphon output Size, and fill in the resolution you want to output (2048 x 768 for this tutorial). Then go to Output > Syphon and that’s it. For more detailed instructions see this tutorial.
To make CoGe generate a Syphon texture, see this tutorial.
To make VDMX generate a Syphon texture, see this tutorial.
For any other player, please check it’s documentation.
Independent of the player, I’ll assume a Syphon resolution of 2048 x 768 in this tutorial (two 1024×768 side by side).
The Blend
Fire Blendy VJ and select your Syphon input as the Source.
By default, it will act like the MadDoubler application from the MadMapper bundle, joining your input with the blend pattern side by side, and generating another Syphon texture. You can see in the preview what it looks like.
There’s pretty much nothing to setup here. You will come back later only to turn on the help patterns when mapping. Let’s just notice a few things…
- Save Config: Will save the current configuration to a file besides the Blendy application with the same name as the app but with the “.blendy” extension. By default, when Blendy starts, it reads it again.
- Load Config… & Save Config…: If you need to save additional configurations, load and save to other “.blendy” files.
- Target Framerate: This is the maximum framerate Blendy will try to deliver. If your machine is short on processing, lower this so Blendy will not consume more CPU than needed. 25 is usually the less you can get without affecting your performance.
- Syphon Doubler: Enabled by default. If you have a mapping tool where you can select multiple Syphon inputs, you may want to turn it off and output just the blend pattern. As of now, for MadMapper use, the only way to go is with Doubler ON.
Blendy VJ will automatically generate another Syphon texture, there’s no need to turn it on.
The Output
Now the tricky part…
As of now, the only software I know that can map a Syphon input the way we need to map is MadMapper. So you need it to continue. If you know any other software that can do that job, please tell me so I can test it out and update this tutorial.
Mapping the Source
So fire MadMapper and select Blendy VJ as your input.
Map the source part source with MadMapper the way you usually do, ignoring the double light between the projectors. You can read this tutorial to learn the basics of MadMapper.
For the most basic setup, which is a movie on a wall with two projectors, you will need just two layers on MadMapper, one for the left projector and one for the right projector. Naming layers on MadMapper is a good practice, so you may name them “Source Left” and “Source Right”.
You may deduce that this blend approach will lose some resolution on your output, because the same part of your source will be delivered from different projectors. Your output will have to be scaled down a little bit.
Lock the source layers! Once mapped, you don’t want to touch them by mistake while mapping the blend over them.
Mapping the Blend
The blend pattern will be mapped only where the light is doubled. To see better where is this area we need to map, go back to Blendy and turn blend OFF. By default all the mapping helpers are ON, and you will see this:
You will notice 4 new controls:
- Draw Grid: Draws a grid inside the blend patterns so they can be aligned with perfection.
- Paint Blend: Paint each side of the blend pattern with different colors so we can see on the projection where they are. Green for left and red for right side.
- Paint Source: Paint the entire source with blue so we can see where the double light is.
- Blend Size: Control to adjust the size of the blend pattern. There’s no need to touch it unless your double area is too large.
Now that all the projectors are outputting only blue, create a new layer on MadMapper, map it over the Green pattern (left) and put it right over the double light area coming fom the left projector. RGB math will make it cyan.
Name this layer “Blend Left” and turn this layer OFF on MadMapper.
Do the same for the right projector. Map the Red pattern (right) over the double light of the right projector. RGB math will make it magenta. Name this layer “Blend Right”
Turning off Paint Source on Blendy and MadMapper will look like this::
On the projection, the “Blend Left” layer (green) and the “Blend Right” layer (red) will add making a one single yellow layer. Fade out the source on Modul8 (or your player of chouice), the only color you want to see projected is Yellow.
If everything is in place the left grid and the right grid will match one above the other. If not, turn on Panit Source on Blendy adjust the layers until they are exactly above one another, and not leaking. If there’s any color than blue (the source) and white (source + left + right), there’s some layer slightly off.
Now turn Blend ON on Blendy and your projectors should be blended.
You may notice that the middle of the blend is a little darker. That’s because the addition of light is not linear, so we need to do a gamma correction. Go to Blendy and rise the Gamma Global until the blend is perfect.
What Else?
You can blend more than two projectors with the exact same technique, using the same blend pattern for each edge. Just setup the projectors, map your source over them all and the right/left pattern on each edge.
It is a planned feature of Blendy to make a blend pattern for projectors aligned vertically. Meanwhile, if you really need to do this, use the same technique, but turning the blend patterns by 90 degrees.
There are Modul8 and MadMapper templates in the application zip.
Any doubts, please comment below.
Good blending!
Hi. Nice tool. It will be helful if u can make a video tutorial of blending. Thanx Florian
I it possible to pay by mastercard but no paypal?
Hello,
it should also be possible with: www.millumin.com/
best
@ florian: Hey, thanks!! Yes, I will do a video tutorial very soon…
@pixelschubser: Yes, I heard it has Syphon output.
@flcanga: I’m planning to accept other payment methods, but it can take a while . I’m using PayPal because it’s very easy to setup.
very nice piece of software, will purchase soon
a few words about the templates: you have to re-adjust your madmapper-template, its not very precise (zoom in and you´ll see what i mean).
@Visualprime: I made this MadMapper example template without a TrippleHead, when writing the tutorial, so it must be off. I’ll update the zip when I make aproper one. Or you could send me a fixed version if you don’t mind.
Hello,
I tested Blendy with Millumin, and they work pretty well together
Blendy can send output to Millumin, as well as getting input from Millumin.
Keep making good things,
Philippe
Excellent!!! Great work indeed!!!
Keep on rocking!
can it be desathorized like m8 and MM ?
@ngr: I’m working on that. Meanwhile if you need to deauthorize please contact me.
Like the blog
Hello, could you please make a video tutorial for this? I bought the software from you the other day so I would really appreciate it if for the sake of my 33 euros and anyone else who had paid for this a video tutorial would be much help. Thank you
Yes, I will make a video tutorial soon.
The lack of video tutorial is one of the reasons why Blendy VJ is in a pre-release status.
I mean, it is not finished yet.
por favor faca um video tutorial… e eu ambem gostaria de saber se tem como fazer a juncao dos projetores usando o monitor in e out ou precisa de um aparelho diferente para manda um cabo vga para cada projetor
Sim, vou fazer o video tutorial logo… Para enviar os sinais voce precisa de uma placa de video com 2 saidas adicionais (além do seu monitor), ou de uma placa TippleHead2Go.
Just bought this to do a 2xScreen blend…. As there seems to be no video tutorial, I wonder if you could elaborate on the process of the initial SOURCERIGHT & SOURCELEFT creation in MadMapper..?? Do the 2 quads need to be the same size?? And how do you guess this size to fit exactly the 2 projectors? Any help or advice gladly appreciated. PHIL
On a 2 projector set, Source Left will be displayed by the left projector, and Source Right will be displayed by the right projector.
They have a slice of the image that is equal, the slice that is actually blended.
They don’t have to ge the same size, but usually will.
You have to place them on the edge of each projector, and map the texture on the quad in a way that the doubled light area (that will be blended) will have the exact same image,
Thanks ‘rsodre’ – i thought that might be the case, but I am just wondering how I can get this “exact” as MadMapper currently has no ways of defining quad size precisely.
I am looking at taking a 1000×300 image and mapping using 2 1024×768 projectors, but want to try and ensure that the two sides do not like distorted when compared.
Any ideas…..
In your tutorial above, were the LEFT and RIGHT quads created randomly or just approximated, as I can see yself having concerns about the final image.
As before, all help gladly appreciated
PHIL
Hmm….. The more i think about this (away from my projectors) the more i’m struggling..
It seems like i have to GUESS the overlap when creating the LEFT and RIGHT quads. I can easily make the size of the 2 quads the same by duplicating, but after that, regarding the mapping on the surfaces I am lost
Anyone help me here!!??!!
PHIL
Just fit your image in the space you have the best way you can.
When this is done, turn OFF blend on Blendy and everything will become blue, so you can see where the projectors are overlapping, and place the blend patterns there.
You can also create a huge blue quad all over the output just to see the area you have.
Yep… got it now !!! Works a treat ! Thanks – PHIL
interesante, donde puedo bajar la demo?
Aca: blendy.studioavante.com/download/