CGM to TCR Converter

Convert CGM drawings to TCR ebook format online

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Psion Compatible

TCR delivers content to Psion devices. Convert CGM technical drawings for legacy PDA ebook readers.

Effortless

Upload CGM, select TCR, download. The entire conversion process is automated — no manual configuration needed.

Data Security

Uploaded CGM files are removed after conversion. TCR outputs are purged within 24 hours from Convertio servers.

How to convert CGM to TCR

1

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

2

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

3

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

About formats

CGM (Computer Graphics Metafile) is a vector graphics standard defined by ISO 8632, first published in 1987 and developed through the ISO/IEC JTC 1/SC 24 committee. The standard defines a device-independent format for storing and transferring two-dimensional vector graphics, raster images, and text. CGM supports three encoding methods: character encoding (compact text representation), binary encoding (efficient machine-readable form), and clear-text encoding (human-readable for debugging). The format describes graphical primitives including polylines, polygons, ellipses, circular arcs, splines, and text with associated attributes for color, line style, fill patterns, and clipping boundaries. CGM found its strongest adoption in technical documentation, particularly in aerospace, defense, and industrial sectors where long-term archival and precise technical illustration are critical. One advantage is formal standardization — as an ISO standard, CGM provides vendor-neutral, specification-driven interoperability guaranteed across compliant implementations. The format's adoption in specialized industries is another practical strength: WebCGM, a W3C profile of CGM, became the mandated illustration format for interactive electronic technical manuals in the aerospace industry (ATA iSpec 2200), ensuring CGM's continued relevance in aviation maintenance documentation. While general-purpose vector work has moved to SVG and PDF, CGM persists in regulated industries where certified, standards-based graphics interchange is mandatory.
Initial release: 1987
TCR (Text Compression for Reader) is a compressed plain-text ebook format developed by Barry Childress in the early 1990s for the Psion Series 3 family of palmtop computers. The format was created for Childress's Reader3 application, a text file viewer that needed to fit large books into the Psion's extremely limited storage — typically 128 KB to 2 MB of available memory. TCR uses a dictionary-based compression scheme derived from the earlier ZVR format by Ian Giddings, replacing repeated byte sequences with single-byte tokens that reference a header dictionary. This straightforward approach achieves compression ratios of roughly 40-60% on typical English prose while requiring minimal CPU resources for decompression. The Psion Series 3 ran on a 3.84 MHz NEC V30 processor with no floating-point unit, so TCR's low computational overhead was essential for smooth page-by-page reading. A key advantage is remarkable storage efficiency for its simplicity — users could carry dozens of novels on removable SSD cards that held only a few hundred kilobytes. The format found a dedicated user community among Psion enthusiasts who built libraries of compressed literature for portable reading years before smartphones existed. Though the Psion platform faded from the market in the early 2000s, TCR files can still be opened and converted by modern ebook tools, and the format stands as an early example of purpose-built mobile reading technology from the pre-smartphone era.
Developer: Barry Childress
Initial release: 1993

Frequently Asked Questions

Why convert CGM to TCR?

TCR is a compressed text format for Psion devices. CGM to TCR converts technical drawings for viewing on Psion-compatible ebook readers.

What reads TCR files?

Psion devices, Calibre, and some legacy PDA ebook readers can open TCR format files.

Is TCR still relevant?

TCR is a legacy format for Psion PDAs. It remains useful for compatibility with these historical devices and emulators.

Is the conversion free?

Standard CGM to TCR is free on Convertio. Premium plans offer higher capacity for frequent conversions.

Any platform restrictions?

None — the converter is browser-based and works on all operating systems and device types.