How Do I Track a Color in Video Without TouchDesigner?
Load a video in BeamTracer Performer, add BOXES, and choose TARGET → FOLLOW → COLOR. Use PICK FROM PICTURE to select a hue, narrow HUE RANGE, and raise MIN REGION AREA to reject small matches. Add PLEXUS with the same target settings to connect the regions, then render MP4 or WebM.
The flower keeps turning while the minimum region area changes from 0.12% to 0.20%. The source is an animated version of BeamTracer's Flower artwork. Boxes and lines come from the app's native render.
Hi, I'm Trina with BeamTracer.com. A color key gives you a useful way to draw attention to parts of a picture: cyan petals, a bright costume, or colored props on a stage. The boxes follow the matching patches as they move. You can connect those patches without building a tracking network.
How do I put tracking boxes around a selected color?
Choose COLOR as the target for BOXES, then sample a saturated part of your video. The tracker groups neighboring matching pixels into regions and fits boxes around them. A wide range can join neighboring colors into one large region, so begin with a narrow match.
- Open BeamTracer Performer and open FX Rack.
- Load a video with VIDEO · IMAGE, or choose FLOWER to try a still picture first.
- Add BOXES from ADD AN EFFECT → SOURCE & TRACKING, then select its row to open the controls.
- Open TARGET, choose FOLLOW → COLOR, and select PICK FROM PICTURE.
- Click the color in the small source-picture preview, then close PICK FROM PICTURE and adjust HUE RANGE.
- Set BOX STYLE → FRAME and lower BOX COUNT if too many regions compete for attention.
- Open RENDER, choose MP4 · H.264 or WEBM · VP9, render the video, and choose SAVE VIDEO.
You can download the turning-flower source to follow this example. The built-in FLOWER is a still image; the downloadable clip adds a gentle turn so you can see the boxes update over time.
Hue 185°, Hue Range 10°, Hue Softness 4°, Min Saturation 0.35 and Min Region Area 0.12%. Boxes use Frame style; Plexus uses Delaunay links.
How do I stop the boxes from finding every tiny speck?
Raise MIN REGION AREA to remove small connected regions. Use MASK PREVIEW to inspect which pixels pass the color key before changing the area cutoff. A clean key makes the boxes easier to read.
| Control | What to change |
|---|---|
| HUE | Move the center of the selected color range. Use the picker to find a starting value. |
| HUE RANGE | Narrow the selection when nearby colors merge; widen it when a moving patch drops out. |
| HUE SOFTNESS | Soften the transition at the edge of the hue selection. |
| MIN SATURATION | Raise it to reject washed-out or nearly gray pixels. |
| MIN REGION AREA | Raise it to keep larger regions and discard smaller ones. |
The color key is unchanged. Min Region Area is now 0.20%, with the same Box Count and Live Numbers settings. Compare the smaller cyan patches with the previous clip.
MASK PREVIEW shows the color selection in black and white. It is a diagnostic view; the preview itself is not part of the exported artwork. Minimum area filters the connected regions after that selection, so increasing the cutoff can remove a box while its white patch remains visible in the mask.
Sample the source picture
Use the small preview opened by PICK FROM PICTURE. Sampling a bright, saturated area gives a clearer hue than choosing a gray highlight or deep shadow. If the picture's lighting changes, adjust the key while that part of the video plays.
How do I connect the matching regions with lines?
Add PLEXUS, open its TARGET, and give it the same FOLLOW → COLOR settings as BOXES. Each effect has its own target controls, so changing the boxes' key does not automatically change the lines' key.
For the example above, copy Hue 185°, Range 10°, Softness 4°, Min Saturation 0.35 and the chosen minimum area into both effects. Under PLEXUS, choose LINKS → DELAUNAY. Under STYLE, set LINE COLOR to a pale mint such as #d6ffed so the annotations stay visible over the petals.
Keep the source playing while you tune the result. A region may separate into several patches as it turns, then join again. Connecting those changing regions can be the point of the composition; a dense web of lines may call for a higher area cutoff or fewer boxes.
Color regions do not have permanent identities
COLOR 01, COLOR 02 and the other labels describe the current regions in area order. They can change when regions split, merge or cross. Use FACE or HANDS to follow anatomical landmarks, or OBJECTS to detect supported object classes.
Is this the same as a TouchDesigner blob-tracking patch?
BeamTracer covers the color-selection, region-box and connecting-line workflow shown here. TouchDesigner lets you build a custom image-processing network around a tracker. Xtal's Blob Tracking + Block Edge tutorial is a useful reference for how tracking annotations can sit within a more heavily processed image. Its block-edge treatment is an additional part of that look.
Here, start with the matching regions and make the annotations readable before stacking another effect. If you want a hand-controlled window instead, follow the ASCII and hand-frame tutorial. For the target and picker reference, see tracking effects.
How do I save the look and use another video?
Use SAVE LOOK to keep the effect settings, then load another source with VIDEO · IMAGE. Recheck PICK FROM PICTURE and MASK PREVIEW on the new video: the saved hue may match something completely different under new lighting. Render a short range as MP4 or WebM and watch it through before exporting the whole performance.