XC to OTB Converter

XC to OTB conversion — online, no install needed

Drop files here. 1 GB maximum file size or Sign Up
to
Facebook Amazon Microsoft Tesla Nestle Walmart L'Oreal

Quality Output

Output quality matters. The converter produces well-encoded OTB files that maintain the integrity of your source XC data.

Visual Fidelity

Your XC visual data maintains its quality through the conversion pipeline — the OTB output looks accurate.

Format Flexibility

Choose from a wide range of output formats for your XC data. OTB is one option among many supported targets.

How to convert XC to OTB

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose otb or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your otb file right afterwards

About formats

XC (X window Color) is a procedural pseudo-format built into ImageMagick, the open-source image processing suite originally created by John Cristy at DuPont and first released on August 1, 1990. Rather than reading pixel data from a file, the XC format generates a solid-color canvas of specified dimensions, filled with a single uniform color value. The color can be specified using any of ImageMagick's supported color specification methods: named X11 colors (red, dodgerblue, linen), hex triplets (#FF6600), RGB/RGBA functional notation (rgb(255,102,0)), HSL, CMYK, or any other supported color space representation. XC canvases are created through ImageMagick's command-line interface using the special colon syntax (e.g., convert -size 800x600 xc:navy output.png) and serve as foundational building blocks in ImageMagick's compositing and image construction workflows. Common uses include creating background layers for compositing operations, generating masks and mattes of specific colors, initializing canvases for drawing operations, producing test images for pipeline validation, and creating placeholder images for web and application development. One advantage is workflow integration: XC canvases feed directly into ImageMagick's processing pipeline, enabling operations like gradient overlays, text rendering onto colored backgrounds, or template generation without requiring any input file. The pseudo-format's support for ImageMagick's complete color specification system is another strength — any color expressible in any supported color space can be used, including semi-transparent colors via RGBA notation, making XC a versatile primitive for programmatic image construction.
Initial release: 1990
OTB (Over-the-Air Bitmap) is a monochrome image format developed by Nokia as part of their Smart Messaging specification in 1997, designed for transmitting small graphics — operator logos, group graphics, and picture messages — to Nokia mobile phones via SMS. OTB files contain 1-bit (black and white) images at small fixed resolutions, typically 72x14 pixels for operator logos and 72x28 pixels for group graphics, encoded in a compact binary format suitable for embedding within the payload of SMS text messages. The format uses a simple structure: a header byte indicating whether the image is an operator logo or group graphic, width and height values, and the raw bitmap data where each bit represents one pixel packed eight per byte. The extremely tight format — designed to fit within a single SMS message (140 bytes maximum payload, shared with addressing overhead) — reflects the severe constraints of mobile communication in the late 1990s. Nokia's Smart Messaging system was one of the first commercial implementations of rich content delivery to mobile phones, and OTB images represented the entire visual content capability of Nokia handsets before MMS and mobile data browsing arrived. One advantage is the format's historical role as a pioneer of mobile visual messaging: OTB images were among the first graphics that ordinary consumers could send to each other's phones, predating MMS, camera phones, and smartphones by nearly a decade. The format's minimal footprint is another characteristic — entire images fit in a few dozen bytes, reflecting an era of extreme bandwidth constraints. OTB files are supported by ImageMagick, various Nokia phone management tools, and specialty mobile format utilities.
Developer: Nokia
Initial release: 1997

Frequently Asked Questions

Why convert XC to OTB?

The XC format has limited viewer support. Converting to OTB ensures broad compatibility across devices.

How do I open OTB files?

Mobile device tools will handle OTB files without issues. The format is well-supported across platforms.

What quality can I expect from OTB output?

The OTB format offers monochrome mobile bitmap — Convertio ensures optimal encoding during the conversion process.

Do I need to register to convert XC to OTB?

No account is required. You can convert XC to OTB directly without signing up — just upload, convert, and download.

Do I need to install anything?

No installation required. Convertio runs in your web browser — just open the page, upload your XC file, and convert.

Can I convert multiple XC files at once?

Yes, batch processing is available. Add multiple XC files simultaneously and download each OTB result separately.