RLE to RB Converter

Transform compressed rasters into RB documents online

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

Multi-File Processing

Queue several RLE files at once and convert them all to RB simultaneously. Batch mode streamlines repetitive conversion work.

Server-Side Speed

Heavy lifting happens in the cloud — your device resources are untouched while RLE images are processed into RB format.

Simple Workflow

Upload RLE, pick RB, download the result — the three-step process makes converting legacy formats effortless for anyone.

How to convert RLE to RB

1

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

2

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

3

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

About formats

RLE (Run-Length Encoded) in the context of the Utah RLE format refers to a raster image file format developed by Spencer W. Thomas at the University of Utah's Computer Science Department around 1983, as part of the Utah Raster Toolkit. The format stores images using a scanline-oriented run-length encoding scheme that compresses sequences of identical pixel values into count-value pairs, achieving good compression ratios for images with large areas of solid color — typical of computer-generated graphics and rendered scenes common in computer science research at the time. Utah RLE supports 1 to 255 color channels per pixel, with 8 bits per channel, and includes a header specifying image dimensions, number of channels, background color, and an optional color map. The format accommodates alpha channel data as an additional channel, and empty scanlines (matching the background color) can be omitted entirely for further compression. The Utah Raster Toolkit provided a suite of Unix command-line tools for manipulating RLE images — operations like compositing, scaling, rotating, color manipulation, and format conversion — establishing a software paradigm later echoed by Netpbm and ImageMagick. One advantage is the format's foundational role in computer graphics: the Utah Raster Toolkit and its RLE format emerged from the same research environment that produced the Phong shading model, Gouraud shading, and the teapot — and much of the early computer graphics research output was stored in this format. The format is supported by ImageMagick, GIMP, and various legacy graphics tools.
Initial release: 1983
RB is the native ebook format of the Rocket eBook, one of the first commercially available dedicated e-reading devices, developed by NuvoMedia and released in October 1998. Founded by Martin Eberhard and Marc Tarpenning — who later co-founded Tesla Motors — NuvoMedia designed the Rocket eBook as a handheld device with a reflective LCD screen, capable of storing approximately ten books in its internal memory. The RB format packages HTML-based content along with embedded images, metadata, and a table of contents into a single binary container optimized for the device's limited hardware. Content was purchased and downloaded through NuvoMedia's RocketLibrarian desktop software. A notable advantage of the format was its early support for bookmarking, annotation, dictionary lookups, and adjustable font sizing — features now standard on modern e-readers but revolutionary in the late 1990s. The Rocket eBook demonstrated viable commercial demand for dedicated reading devices, paving the way for subsequent platforms from Sony, Amazon, and others. NuvoMedia was acquired by Gemstar-TV Guide International in 2000, which discontinued the device line in 2003. While RB files are largely a historical curiosity today, they can be converted to modern formats using ebook management tools, and the format remains significant as a pioneering chapter in the evolution of digital reading.
Developer: NuvoMedia
Initial release: 1998

Frequently Asked Questions

Why convert RLE to RB?

Utah RLE is an academic format with very limited tool support. Converting to RB ensures your computer graphics research data remains accessible.

What programs can open RB?

RocketBook readers and Calibre open RB ebooks. This legacy format was designed for the original NuvoMedia Rocket eBook device.

Is the conversion from RLE to RB lossless?

Since RB supports lossless storage, the pixel data carries over without degradation. The result faithfully represents the source RLE image.

How quickly can I convert RLE to RB?

Most RLE images convert to RB within seconds. The exact time depends on the resolution and complexity of the source, but it is typically quick.

Can I convert multiple RLE images at once?

Absolutely. Add several RLE images at once, set RB as the output, and the converter processes them all in parallel for maximum efficiency.