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HRZ to DJVU Converter

Turn HRZ images into DJVU format with ease online

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Visual Fidelity

Your HRZ imagery is carefully converted to DJVU with maximum quality retention. No unnecessary degradation during the transformation process.

Privacy Protected

Uploaded HRZ data is erased immediately after conversion. DJVU results are purged within 24 hours — your content stays confidential.

Any Device Works

Run the HRZ to DJVU converter from any device — desktop, laptop, tablet, or phone. All you need is a web browser to get started.

How to convert HRZ to DJVU

1

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

2

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

3

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

About formats

HRZ is a simple raster image format associated with slow-scan television (SSTV), a method of transmitting still images over radio frequencies used by amateur radio operators since the late 1950s when Copthorne Macdonald pioneered the technology. HRZ files store images at a fixed resolution of 256x240 pixels in raw RGB format, with each pixel represented as three bytes (red, green, blue) at 8 bits per channel, producing uncompressed files of exactly 184,320 bytes. The format has no header, no metadata, and no compression — the file is simply a sequential dump of raw pixel data in row-major order. This extreme simplicity reflects the format's origins in the amateur radio community, where SSTV images are transmitted as audio tones encoding luminance and chrominance values over narrow-bandwidth HF (shortwave) radio channels. The fixed 256x240 resolution corresponds to common SSTV transmission modes, and HRZ files serve as the digital capture or storage medium for received SSTV transmissions. One advantage is the format's zero-overhead structure: with no parsing, decompression, or metadata processing required, HRZ files can be read by any program capable of reading raw pixel data with known dimensions — a single function call in virtually any programming language. The format's connection to amateur radio SSTV culture is another notable aspect: HRZ files document a unique form of image communication where operators transmit photographs over thousands of miles using nothing but radio waves and audio encoding, a practice that continues today alongside digital modes. HRZ files can be opened by ImageMagick, GIMP, and specialized SSTV software.
Developer: SSTV Community
Initial release: 1985
DjVu (pronounced "deja vu") is a document format developed at AT&T Labs by Yann LeCun, Leon Bottou, Patrick Haffner, and Paul Howard, first released in 1996. The format was specifically designed for storing scanned documents and images at very high compression ratios while maintaining visual quality suitable for on-screen reading. DjVu achieves this through a layered approach: the document image is separated into a foreground layer (text and line art at full resolution), a background layer (photographs and textures at reduced resolution), and a mask layer that determines which layer is visible at each pixel. This separation, combined with purpose-built compression algorithms for each layer type, typically produces files 5-10 times smaller than equivalent JPEG or PDF scans. One advantage is exceptional compression on scanned pages — a 300 DPI color scan that might occupy 25 MB as TIFF or 500 KB as JPEG typically compresses to 40-80 KB in DjVu while preserving legible text. The progressive rendering model is another strength: DjVu files stream efficiently over networks, displaying a readable low-resolution version almost immediately while progressively refining to full quality. The format supports multi-page documents, embedded text layers for searchability, hyperlinks, annotations, and a shared dictionary mechanism that further compresses collections of similar pages. DjVu is widely used by libraries and archives for digitized historical documents and manuscripts.
Developer: AT&T Labs
Initial release: 1996

Frequently Asked Questions

Why convert HRZ to DJVU?

HRZ requires niche software to open. Converting to DJVU lets you share and view your SSTV images on virtually any platform.

What programs open DJVU?

Open DJVU with Microsoft Word, LibreOffice Writer, Google Docs, or any modern office application — supported across platforms.

Is batch HRZ to DJVU conversion supported?

Absolutely — queue multiple HRZ images and convert them all to DJVU in a single session. No need to process one at a time.

Does the conversion preserve quality?

The converter retains maximum fidelity during the HRZ to DJVU transformation. Any differences stem from the output format's own characteristics.

What platforms are supported?

The converter works on any device with a browser — Windows, macOS, Linux, iOS, Android. No platform-specific software needed.