RGBO to OTB Converter

Free online RGBO to OTB image conversion

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Quality Preserved

Your original RGBO visual data transfers cleanly to OTB format. The converter maps pixel content accurately without unnecessary loss.

Easy to Use

Converting RGBO to OTB takes just a few clicks. The clean interface guides you through uploading, choosing output, and downloading.

Data Protection

Your uploaded RGBO data is deleted right after conversion, and the OTB output is removed from servers within 24 hours — keeping your content private.

How to convert RGBO 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

RGBO is a raw pixel data format designation used by ImageMagick, the open-source image processing suite first released in 1990, representing images as a flat sequence of Red, Green, Blue, and Opacity (inverted alpha) sample values with no header, container, or compression. The RGBO channel ordering specifies that the fourth channel is opacity rather than alpha — where alpha represents transparency (0 = transparent, max = opaque), opacity represents the inverse (0 = opaque, max = transparent). This distinction matters in compositing pipelines where the mathematical convention for the fourth channel varies between systems: some compositing models work with alpha (transparency), while older conventions including portions of ImageMagick's internal processing historically used opacity. RGBO files contain raw sample data at a user-specified bit depth (8-bit, 16-bit, or floating-point per channel), with pixels stored in scanline order. Because there is no header, the image dimensions, bit depth, and endianness must be specified externally when reading the file — typically via ImageMagick command-line arguments. One advantage is direct compatibility with processing pipelines that use the opacity convention: RGBO eliminates the need for channel inversion when interfacing with systems that expect opacity rather than alpha, preventing subtle compositing errors that occur when transparency conventions are mixed. The format's raw-data nature provides another practical benefit — with no encoding overhead, RGBO data can be memory-mapped, processed with SIMD instructions, or piped between processes with minimal latency. RGBO is primarily used within ImageMagick processing chains and can be converted to any other format using ImageMagick's extensive format support.
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 RGBO to OTB?

Raw RGBO data lacks compression and file headers, making it unviewable in standard tools. OTB provides a structured, widely supported alternative.

What programs open OTB files?

OTB files can be opened in Nokia phone tools, XnView, and legacy mobile device management applications.

How does Convertio protect my uploaded data?

Your RGBO data is encrypted during transfer and deleted after processing. Converted OTB outputs are purged from servers within 24 hours.

How long does RGBO to OTB conversion take?

Most conversions finish within seconds. Processing time depends on your data size and server load, but results are typically ready almost instantly.

Does the converter handle batch RGBO uploads?

Absolutely. You can upload multiple RGBO sources simultaneously and convert all of them to OTB in one go — no need to repeat the process.