CONTINUUM MOCHA - QUICK START GUIDE

Integrated into just about every filter in Continuum is the Pixel Chooser matte and masking system which includes the Academy award winning Mocha spline masking and planar tracking system. This system was designed to enable users to quickly and easily generate holdback mattes for filter effects. The Pixel Chooser system has 5 main control groups:

Mocha Masking and Tracking: Used to generate closed spline mask shapes and to track these shapes through the shot. You can create as many spline shapes as is needed to isolate the filter effect to a user specified region in the source and all shapes generated in mocha can be tracked using the Mocha planar tracker. Mocha also includes Matte Assist ML, which can generate trackable mask shapes by simply clicking on the image to isolate an object and then its a single button click to track the mask forwards and/or backwards across all frames.

Mask: Used to generate simple geometric spline shapes such as a rectangle or circle. Although these shapes are not trackable with Mocha, they can be keyframed in all supported hosts.

Gradient: Used to generate linear, circular or split field gradient ramps.

Matte: Used to generate holdback mattes based on pixels from luma, or color channels from the pixel chooser input layer.

Depth Map ML: Used to generate an ai / ml depth map derived from the pixel chooser input layer.

Each of these options can be used in conjunction with each other and be combined to create a still or animated holdback mask / matte for the Continuum filter that is being used.

Here’s a quick overview of the Mocha option in the Pixel Chooser.

Mocha Masking and Tracking

• With a BCC+ filter applied to a clip, twirl open the Mocha Mask and track group and then click on the Mocha Mask button to launch the Mocha custom GUI.
• In the horizontal toolbar at the top of the filter, you’ll see a user interface layout control popup that should show several options including Essentials and this is the layout that we should work with. The other layout options (Classic, Big Picture, Roto) contain a lot of controls that are not necessary for most filter level masking and tracking operations so if Essentials is not the current workspace, select that from the pop-up to make it the current selection. 

Mask shape generation

• Staying with the horizontal toolbar, let’s generate a simple mask shape. Click on the square button labelled “create rectangular x spline layer” and then click + drag in the image to generate a shape.

• The generated rectangular shape will show a red square in the center and this is the mask shape. You can click on any of the corner points to distort or reshape the rectangle. Notice that there is a blue control bar that extends out from the corner - this is a tension bar for the X spline and you can drag this to relax the tension on the corner to generate a rounded corner. Also notice that there is a white dashed rectangle surrounding the entire shape and you can use this to reposition the shape as a whole or you can drag one of these corner points to distort the mask.

Tracking the shape into the shot

• At the bottom of the user interface, you’ll see a row of transport control buttons which you can use to play through the shot or to track the shape into the shot. We’ll do the latter. To track the shape, make sure to first select the shape you wish to track in the layer panel, then click on the “track forwards and backwards” button. Mocha will attempt to track the pixels that are in the shape across all frames in the clip.

Note: There are several other spline generation tools available to us in the top toolbar. You can create freehand x spline mask shapes with the X-Spline layer tool by clicking on the image to create a series of connected points and then control+click or right mouse click to close the shape. If you select the Magnetic Spline tool, Mocha will try to snap the spline shape to feature contours in the image. If you select the Mask ML tool, you can click on an object in the image and Mocha will use its integrated AI / ML model to isolate the object in the frame.

Working with Matte Assist ML

As mentioned above, Mocha includes an AI/ML model that can be used to isolate objects in the frame and then track the mask for these objects across all frames in the shot. Simply select the Mask ML tool, then click on an object in the image. A green dot will appear at the click point in the image and Mocha will initialize the ML model and produce a colored filled mask. To add to the mask just click again and repeat this until the mask covers the object.

To remove the mask from areas in the image that should not be included, hold the Option/Alt key while clicking or alternatively right click on the regions to be excluded. This will generate a red dot and remove the mask from that region. Continue with this until you’re satisfied with the mask shape.

• Next, we need to convert the mask generated by Matte Assist ML into a trackable spline shape. To do that, just select the solid black arrow picker tool from the top toolbar. This action will instantly convert the mask preview into a live spline shape. The spline shape is now ready to be tracked through the shot. Note that you can also choose to modify the spline shape if desired by repositioning or deleting any of the mask shape points prior to propagating.

• And now we are ready to render and propagate the spline shape into an animated mask. With the spline shape layer selected in the layer panel, click on the Mask tab in the UI and the row of buttons at the bottom toolbar will update from Track to Render. Click on the Render Forwards and Backwards button to render and track the mask into all frames in the shot. Note that the spline shape will instantly be converted into a yellow contour spline that follows the masked object across all frames. While the shape is being rendered and tracked into a mask, you can monitor the process in the viewer.

All that remains after mask generation and propagation is to save the result and exit out of the Mocha user interface and return to the host. Note that you can also export the tracked mask for use in any other Continuum or Sapphire filter instance.

• Select File–>Save Project to save the results into the filter. You can also choose File–>Export Project to save the results to a desktop file. To import this into another filter, simply launch Mocha from a Continuum or Sapphire filter, then select File–>Merge Project and select the saved project file from disc and click on the Open button. Once you have completed working in the Mocha UI, click the Close button located at the top left corner of the Mocha UI and you will be returned to the host.

At this stage, you will have a tracked mask shape that can be modified if necessary using the controls that are available in the Mask group of the filter. Controls include Invert, Feather, Dilate, Feather Bias, and Opacity.

Click here for more information on the Pixel Chooser