Download and install the latest version of Filestar.
Right click on one or more Otb file(s) on your desktop and select Convert with Filestar.
Type grayscale filter in the search box.
Press Run.
Or let an AI agent do it: filestarcli -i photo.otb -c "grayscale filter" (how).
Let your AI agent grayscale OTB filter
Claude Code, Codex, Cursor and other agents can do this on your computer with Filestar. Your files stay on your machine.
Install Filestar and add it to your agents:
npm install -g filestar
filestarcli agent install
Then ask your agent:
“Use Filestar to grayscale OTB filter in my Downloads folder”
Or run it yourself:
filestarcli -i photo.otb -c "grayscale filter"
Runs on your computer, so your files stay on it. Works on Windows, macOS and Linux. 50 free conversions with the npm install, no account needed.
Can my AI agent grayscale OTB filter?
Yes. Install the Filestar CLI with npm install -g filestar and your agent can run filestarcli -i photo.otb -c "grayscale filter" on your computer, so your files stay on it.
The OTB (Nokia Over The Air Bitmap Image) file format is a type of image file developed for use on Nokia mobile devices. These files are specifically optimized for efficient transmission and display on Nokia phones, particularly older models. The OTB format is designed to be compact to facilitate over-the-air (OTA) transmission, which was an essential feature in the era of limited bandwidth and data transfer capabilities. The format supports monochrome graphics, making it suitable for simple images like icons and logos.
