Freej beginner tutorial
Freej is a tool for being VJ. As documentation says, it is a vision mixer, a tool for realtime video manipulation.
This is a tutorial for beginners who want to learn using Freej. This is the first part of tutorial – I plan to write next parts if I see somebody uses and needs it. In this part you will learn:
what is the basic idea of using freej, how its user interface is organized
how to use freej to show movies and static images
- how to use layers, so you can use more than one movie
- how to mix layers with each other
- how to add visual effects to displayed movies
- can use Linux (command line)
- will really do all the exercises from this tutorial -- if you only read it, you'll learn nothing
will let me me know about any problems, comments and suggestions, so I can make this tutorial better
contents
the first start -- how to start and stop freej
user interface -- what is what in freej
mixing two movies (fun starts)
using effects -- basics
installation
The installation of Freej is out of the scope of this document. Freej's website is: http://freej.dyne.org/. Take a look there.
If you want to try Freej without installing it, just use dynebolic live CD.
the first start
[01] Create directory freej_tmp. We will put our images, movies etc in this directory and we will play inside it:
$ mkdir freej_tmp $ cd freej_tmp
[02] Download this image to freej_tmp directory. Now start freej:
$ freej ipernav.png
As a result, freej starts and shows the picture ipernav.png.
user interface
Freej consists of two windows:
- output window – in this window our movies, pictures etc are shown,
console window – this window is used to interact with freej – give commands, load new pictures, movies etc,
[03] In console window, press [?] key (quotation mark). You will see the list of shortcuts.
[04] As you can see, [ctrl+c] means quit. Press [ctrl+c]. You are prompted to confirm that you really want to quit freej. Type yes [enter]
some more fun – movies
- So far we just used static image – not so much fun. But the very same way we can use a movie.
[05] Download this movie to freej_tmp directory. Then start freej:
$ freej kury.avi
As a result, freej starts and shows the movie kury.avi.
Quit the freej (remember? [ctrl+c]).
more layers
- We can load both static image and the movie.
[06] Start freej with both movie and static image:
$ freej kury.avi ipernav.png
As you can see, only chicken movie is visible (and the static image – file ipernav.png – is invisible). We are going to understand why...
Now, when we opened two images (static image and a movie) in freej, we have them on two layers. You can see the list of layers in the console. As you can see, that layers are called VID (which means: video layer) and IMG (static image layer).
The list of layers is also shown in output window. As you can see (below), the video layer is on top of static image layer. This is why we can't see the image. 
Take a look at the console window. As you can see, one of layers (VID) is highlighted. It is the current layer. You can see the detailed information about that layer in the top of console window. You can see there the name of the file (kury.avi) and some other info, which we will understand later.
Notice that current layer doesn't mean top layer or the layer which is visible now. Current layer means just current layer.
[07] While in the console window, you can use left and right arrow keys to change the current layer. Press the right arrow key to change the current layer to IMG layer. Notice that now at the top of the console window you can see the details of static image layer.
[08] While in the console window, you can use page up and page down keys to move the current layer up and down. So now, when the current layer is IMG layer, press page up. As you can see, the static image layer went to the top. Now the static image is visible and the chicken movie became invisible.
Close the freej ([ctrl+c], as you remember).
mixing two movies
As I previously told, freej is about mixing images. Now we will start doing that.
[09] Download another movie to freej_tmp directory. Then start freej:
$ freej kury.avi term.avi
As a result, freej starts. kury.avi is on the top layer, and is visible. term.avi is on the bottom layer and thus is invisible.
[10] Press key [2] in output window. The effect should look like that:
Pressing key [2] we made red blit on active layer. You can see it in layer details, in the top of console window.
As you know, each picture an a computer screen has three channels: red, green and blue. Red blit means that now only red channel of the kury.avi layer is visible. Green and blue channels of this layer became transparent, so now we can see:
the red channel of kury.avi
the green channel of term.avi
the blue channel of term.avi
In very similar fashion we can use green blit (it's [3] key) or blue blit ([4] key). You can also try using other blits (keys [1]-[9]). Also try switching [0] on and off – I don't know what does it do, but you will see the difference.
alpha blit
[11] And now press key [9].
As you can see, now we use alpha blit (you can read it in the info on current layer in the console window). With alpha blit, the current layer becames partly transparent. As you can see, now the layer kury.avi became fully transparent and only term.avi is visible. This is because alpha parameter is zero:
We can change the alpha parameter with mouse. Just press [ctrl+v] in the output window. Now you can move the mouse up and down and alpha will change. When you are done, press [ctrl+v] again. Notice what happens when alpha is about 127 – the current layer becomes half transparent.
Effects
[12] Start freej with term.avi:
$ freej term.avi
[13] In console window press [ctrl+e] (e like effect). You will see the prompt like that:
[14] So just press [tab] and you will see the list of available effects:
[15] Vertigo effect is a nice one. So just type vertigo [enter]. You will see something like that:
disabling and deleting effects
[16] Take a look at the console window. As you can see, the current layer is video layer with file term.avi:
You can also see that this current layer has the effect vertigo:
[17] Press down arrow key in the console window to see the details on this filter:
[18] Press [insert] key to temporarily disable and enable this effect. Press [delete] to delete this effect from this layer.
that's all, folks
I think it's enough for the first lesson. You already know how to mix video and static images using different blits and effects. The next thing to learn will be using freej in fullscreen mode (hint: [ctrl+f]), but I will probably show that in the next tutorial.
[19] If you have some comments, drop them in the guestbook: http://www.rozrywka.jawsieci.pl/materialy/slowo/freej_tutorial/index.php#koniec
metainfo
License: you can do whatever you want with this document, except one thing: you can not distribute it under more strict (more close) license.
Author: my name is Piotr Sobolewski. You can read more about me. You can also contact me.
Main revision: Asbesto, Wintercamp 09.