DC1 File

What are DC1 files and how to open them

Are you having problems opening a DC1 file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your DC1 files.

What is a DC1 file?

A .DC1 file is a DuneGraph Compressed Bitmap file.

DuneGraph Compressed Bitmap is a graphics file format used by the program DGraph on the Atari Falcon. It stores compressed bitmap images in 256-color mode at a resolution of 320×200 pixels. The format lets DGraph save artwork using its own compressed form, reducing storage size compared to raw bitmaps.

These files are produced when DGraph's save command is used with its compressed image option. When opened later, DGraph decompresses the bitmap into full pixel data for display or editing. Uncompressed variants by DGraph use a similar "DG1" format; "DC1" is specifically the compressed version.

Files begin with the three ASCII bytes "DGC" at offset 0 and include the two-byte pattern 0x00 0xFF at offset 8 to help identify this format.

How to open DC1 files

Important: Different programs may use files with the DC1 file extension for different purposes, so unless you are sure which format your DC1 file is, you may need to try a few different programs.

While we have not verified the app ourselves yet, our users have suggested a single DC1 opener which you will find listed below.

Last updated: October 22, 2026

Various apps that use files with this extension

These apps are known to open certain types of DC1 files. Remember, different programs may use DC1 files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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File.org helps thousands of users every day, and we would love to hear from you if you have additional information about DC1 file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.