Convert OTB to CAL
Convert OTB images to CAL format, edit and optimize images online and free.
Drop Files Anywhere to Upload
The OTB (Over The Air Bitmap) file extension, developed by Nokia, is used for transmitting black and white bitmap images between mobile phones, particularly Nokia and Siemens models. These images, with a maximum resolution of 255x255 pixels, are often sent via SMS in either hexadecimal text or binary format. Historically, OTB files were popular in the early days of mobile communication for sending simple graphics, icons, and wallpapers when data transmission speeds were limited.
The CAL file extension, known as CALS (Continuous Acquisition and Life-cycle Support) Type 1 Image, is a 1-bit black-and-white raster image format developed by the U.S. Department of Defense in the mid-1980s to standardize graphics data interchange for military documentation. It is primarily used for storing and sharing monochrome images while retaining orientation metadata. The format supports both uncompressed and compressed (using CCITT Group 4 compression) images.
Drag and drop your OTB file or click Choose File to proceed.
Select customization options for OTB to CAL conversion, then click Convert.
You will be redirected to the download page to obtain the CAL image.
The Vertopal CLI tool provides efficient conversion from OTB image into CAL image.