PDF to OTB Converter

Turn PDF documents into OTB bitmaps for free

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PDF to OTB Conversion

Convert PDF pages into compact OTB monochrome bitmaps — perfect for legacy mobile applications and embedded displays.

Secure Processing

Uploaded PDFs are deleted right after conversion, and output OTB files are purged within 24 hours for your privacy.

Effortless Process

Just upload your PDF and pick OTB — Convertio handles the rest with no configuration headaches or technical knowledge needed.

How to convert PDF 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

PDF (Portable Document Format) was developed by Adobe Systems, co-founded by John Warnock and Charles Geschke, with the first version released on June 15, 1993. Built on a simplified PostScript imaging model, PDF encapsulates complete document descriptions — text with fonts, vector graphics, raster images, and interactive elements — in a self-contained file that renders identically across every platform, device, and printer. The format evolved through multiple versions, culminating in its adoption as international standard ISO 32000-1 in 2008 (PDF 1.7) and ISO 32000-2 in 2017 (PDF 2.0), ensuring long-term vendor independence. PDF supports an extraordinary range of capabilities: digital signatures, form fields, annotations, bookmarks, accessibility tags, encryption, JavaScript, multimedia embedding, 3D content, and archival-specific profiles (PDF/A). One advantage is absolute visual fidelity — a PDF document looks exactly the same whether opened on Windows, macOS, Linux, iOS, or Android, printed on any printer, or viewed decades after creation. Universal software support is another core strength: PDF viewers are built into every major operating system and web browser, and the format is read by hundreds of applications worldwide. Specialized ISO profiles like PDF/A (archival), PDF/X (print production), and PDF/UA (accessibility) extend the format's reach into regulated industries. PDF has become the global standard for document exchange in business, government, legal, academic, and publishing contexts.
Developer: Adobe Systems
Initial release: June 15, 1993
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 PDF to OTB?

OTB is the Nokia Over-The-Air Bitmap format — converting PDF to OTB creates small monochrome images for legacy mobile devices.

How do I open an OTB file?

OTB files are supported by ImageMagick, XnView, and older Nokia phone firmware. GIMP can also handle this format.

Will the PDF colors be preserved?

OTB is a monochrome format, so the output will be a black-and-white bitmap representation of each PDF page.

Can I convert several pages at once?

Each page of a multi-page PDF is converted individually, giving you one OTB image per page of the original document.

Is PDF to OTB conversion free?

Convertio provides free PDF to OTB conversion. Heavier workloads are supported through premium subscription plans.

PDF to OTB Quality Rating

4.5 (39 votes)
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