Your First Graph
In ArcBrush you don’t edit a picture directly. You build a short chain of steps, a graph, and the picture flows through it. This page builds one that makes a web-ready copy of a photo: smaller, with its tones corrected, saved as a JPEG. Any photo of yours will do.
Each box is a node that does one thing, and the wires carry the picture from left to right. Nothing in the chain is final: you can change any step at any time, and everything after it updates.
The four panels
Section titled “The four panels”The window has four main panels. You’ll use all of them on this page:
- Node Graph, the canvas in the middle, where you place and wire nodes.
- Preview, which shows the output of whichever node is selected.
- Parameters, the settings of the selected node.
- Library, a searchable list of every node.
You can drag them anywhere; Panels & Layout covers that.
Bring in a photo
Section titled “Bring in a photo”Drag a photo from your file manager onto the Node Graph. An Image In node appears with a thumbnail of it, and the Preview shows it. A photo taken on a phone or camera is turned upright automatically.
To add it from inside ArcBrush instead, right-click the canvas (or press Tab), type “image in”, and pick a file with the folder button next to Image File in the Parameters panel.
Make it smaller
Section titled “Make it smaller”Drag from the small square on the right edge of Image In, its output pin, and let go on empty canvas. The Add Node menu opens, showing only nodes that can take a picture. Type “resize” and pick Resize: it lands already wired in.
To get a photo 1600 pixels wide whatever its original size, set Resize to:
Width (keep aspect) works out the height from the width, so the photo is never squashed. Lanczos gives the sharpest result when making an image smaller.
Correct the tones
Section titled “Correct the tones”Drag off Resize’s output pin the same way and add Levels. With Levels selected, the Preview shows the corrected photo, updating as you work:
- Auto: Contrast sets the darkest and brightest points from the photo itself, a good first try on a flat or hazy picture.
- Input White, dragged lower, brightens the photo; Input Black, dragged higher, deepens the shadows.
- Gamma brightens the midtones (above 1.0) or darkens them (below 1.0) without moving black and white.
- The eyedropper beside Input White sets the white point from the photo: click it, then click the part of the Preview that should be pure white.
Press D with Levels selected to bypass it, and again to bring it back: a quick before and after. Click Image In or Resize to see the photo at that step; selecting a node never changes anything.
Levels is one choice of many. Swap in Exposure, Curves, Color Balance, or a filter such as Sharpen, which is often worth adding after a resize, and wire it the same way.
Save the project
Section titled “Save the project”Press Ctrl+S (Cmd+S on macOS) and save the project, for example as beach.arcb in D:/Photos. Do this before you export: a short path like export/beach.jpg is resolved next to the project file, so until the project is saved it has nowhere to go.
Export
Section titled “Export”Drag off Levels’ output pin and add Export Image. In its Output Path, type:
export/{name}_web.jpg {name} is a token: it is replaced by the photo’s own name, so the file is called after whatever photo you loaded. The .jpg ending makes it a JPEG, and Quality trades file size against detail. The Writes line shows the exact file before anything is written.
Click Export. ArcBrush writes the file, and the node shows its name, how long it took, and its size. Building the graph never writes anything on its own; files are written only when you export.
Run it again on another photo
Section titled “Run it again on another photo”Select Image In, click the folder button next to Image File, and pick a different photo. Every step runs again on the new photo: it is resized, corrected, and the Writes line now names the new file. Click Export on Export Image again.
That is the point of a graph. The work you did is a recipe, not a one-off edit, and it is ready for the next picture. Tweak Levels later and only the steps after it run again.
Where to go next
Section titled “Where to go next”The Node Reference describes all 124 nodes.