Feedback Source Plugin Tutorial

One exciting new feature of Resolume 2.3 is the Feedback source plugin. With this plugin you can create feedback effects. You have probably seen a feedback effect in action by pointing a video camera at a TV screen that is showing what the camera is registering. If you have never done this you should try it! It's fun but do not blame us if you accidentally hypnotize yourself!

A feedback effect is achieved by feeding the video back into the original video and mixing it. Optionally you can apply effects to the feedback to achieve various effects.

The Feedback source plugin in Resolume enables you to apply feedback effects to your footage but it can also be used to generate abstract imagery without the use of any premade footage!

To activate the feedback source plugin for use you need to drag it from the sources tab on the left to a channel like you also do with a video clip. To apply the feedback to one of your video clip’s make sure you have one playing in the bottom layer and then put the feedback on the middle or top layer. Now blend that layer with the feedback with various overlay modes, Alpha (a), Lighten (li) etc. and try moving the layer opacity slider up and down to see what various values do. The visual result will mostly consist of some trailing effect.

Now try one of the push transitions (you’ll find the push-up, -down, -left, -right when you right-click the small top left button on the blend modes palette. Now set the layer opacity slider to a high level ~90 and see what happens.

This is nice but not extremely sexy yet. What we need are effects! By applying effects to the feedback you can get some totally unexpected results. For instance apply the Spray Vertical effect to the feedback. Set the overlay mode to Alpha or Lighten and slide it from 0 to 100. The image will be smeared of the screen to the bottom! Leaving either some stripes or a one color image. Did you expect that to happen? Neither did we!

Let’s try a different effect on the feedback. The PanSpinZoom freeframe effect by Pete Warden is very useful. Set the overlay mode to alpha, lighten or Lumakey opacity ~50. Now apply the PanSpinZoom to the feedback. Nothing happens yet. Now slide the Scale parameter of the effect left to right to see what it does. Pretty cool huh!? Also try the Rotation and x and y position parameters for more wicked results.

It is also possible to create some crazy abstract imagery with the feedback plugin without the use of any premade footage. Here is a simple example. Clear all the layers and put the feedback plugin in the bottom layer. Obviously nothing will happen and the screen will stay black. Set the transition of that layer to Push Down and set the slider to ~95. Still nothing happens but let’s see what happens when you start changing the background colour. To open the background colour picker right-click the little coloured button next to the record button. Click and drag in the colour picker and see the beautiful array of coloured bars slide on you screen!

You can make this even fancier by loading another channel with a feedback plugin and setting this in the middle layer with the ‘Push Left’ transition to ~ 90. Again keep changing the background colour to feed your feedback with new colours.
To facilitate these colour changes we have made a source plugin that simply displays a colour. With the parameters you can set it to a colour. When you automate a parameter (for instance by setting it to play) it keeps changing colour.

From the sources tab drag the HSB colour plugin to a channel. Play this in the bottom layer. Right-click the channel to set the HSB colour plugins’ parameters. Now automate the H parameter by setting it to play forward (by default it is set to pause). You now see a simple colour fading from one colour to the next. Now set the feedback plugin in the middle layer and set the transition to ‘Push Down’ and the slider to ~90. Now you have the same effect as before but yu can watch it play without having to animate the colour by hand.

Let’s make this a bit sexier by applying an effect to the feedback. Drag the Tunnel effect from the effects tab to the channel with the feedback plugin. The result should look something like this picture. As you can see it verry easy to create something that looks like a bad acid trip so please do be carefull with your selection of colours.

Here is another example of an effect that is applied to the feedback. In the bottom layer is the HSB Gradient source plugin and on the middle layer the feedback plugin with the Rect Field effect by Dave Green.

So you have learned the basics of the power of the feedback source plugin. Why don’t you give your mom a call and tell her about the feedback plugin? She’ll love it!