PFClean: The Telerack
In this tutorial you will learn how to use the Telerack node in PFClean. Telerack is PFClean’s ultra high performance video restoration engine. Each Telerack node can only process clips of the same standard format and will apply a single set of restoration parameters to all clips in a node.
01. Setting Up a Project
Follow the instructions in the first Getting Started tutorial to create a project and import the tutorial clips into a Media Bin. Then return to the Workflow Manager, create a Telerack node and connect it to the media bin.
You will notice that once you connected the Telerack node, it’s standard was automatically set to PAL 576. This is because the Media Bin only contains PAL clips. Since the Telerack node applies a single set of parameters to all clips in the node, these clips need to be of a single standard. To ensure this constraint, a standard format has to be set for the node. If the Media Bin contained mixed standards clips, the standard to use would have to be be set manually and all controls in the node will be disabled until a standard format has been set.
02. The Telerack User Interface
Double click on the Telerack node to enter the node. When you first open a Telerack node, you will see the panel at the bottom with the current Worklist containing all clips in the node.
The first clip in the Worklist is automatically loaded into the Cinema and will be updated as we activate and modify the Telerack filters. If you want to review the results of the current Telerack parameters on a different clip, simply click on its thumbnail in the Worklist.
The panel on the left of the Cinema shows the fixed pipeline of restoration filters. You can scroll through Telerack’s restoration pipeline with the cursor up/down keys on your keyboard or by using the mouse scroll wheel.
03. Using Telerack’s Restoration Filters
Play through the first clip to evaluate the defects we are dealing with. The clip suffers from video dropouts, bands and video noise. We are now going to activate the appropriate filters to deal with these issues.
Using Filters / Fix Bands
The topmost filter in the Telerack pipeline is Fix Bands. This filter tackles horizontal bands as are most visible in frame 9. Click the On/Off switch to enable the filter . The filter’s parameters are now available for editing. With its default parameters, we do not see any effect on the image, as the filter is looking for light bands. Click Dark as the Luma Band Type to fix the dark bands in this clip.
Next we are going to address the streaks in the clip. Use the arrow keys or your mouse wheel to scroll to the Fix Streaks filter and enable that filter. This time the default parameters work well and there is no need to adjust.
The next issue we identified in the clip was video noise. Scroll all the way down the pipeline to the De-Noise filter and activate it. In order to increase the denoising, we are going to increase the Intensity setting to 4.0 for all channels. You can do this by adjusting the parameter for each channel individually, or enable the chainlink “gang” button first. With gang enabled, the three channels will be adjusted simultaneously when you modify any one of them.
Click the Playblast button to review the effect of the Telerack pipeline on our clip in real time. You can use the A/B split for a detailed before and after comparison.
Whilst playing back we noticed that there are some streaks left in frames 8 and 11. We are going to fix these with the Dustbust filter. Scroll up to the Dustbust filter and enable it. The filter’s default parameters do remove the streaks, but we are going to adjust them to minimise false positives. As the streaks are light, change the Dustbust type to Light. We are also going to set the Performance level to Better Accuracy.
The Telerack parameters are automatically applied to all clips in the node. Switch to the second clip by clicking on its thumbnail in the Worklist and review the results of the current pipeline with Playblast. Use the A/B split for a before and after comparison.
A Telerack pipeline with all its filter’s settings can be stored in a preset by clicking the Store button in the Telerack presets panel. These presets can then be used in other Telerack nodes in the project, or exported to other projects.
To apply the pipeline stored in a preset in the current Telerack node, select the preset in the Telerack presets panel and click Use.