ERF File

What are ERF files and how to open them

Are you having problems opening an ERF 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 ERF files.

What is an ERF file?

ERF files have multiple uses, and BioWare Entity Resource is one of them. Read more about the other uses further down the page.

BioWare Entity Resource File

These ERF files contain the entities and models used by Bioware, video game developers who specialize in role-playing video games. These models that are saved consist out of shapes, materials, and other information that create or define the model.

How to open ERF files

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

While we have not verified the apps ourselves yet, our users have suggested ten different ERF openers which you will find listed below.

Last updated: January 22, 2025

All known file formats using extension .ERF

While BioWare Entity Resource File is a popular type of ERF-file, we know of 3 different uses of the .ERF file extension. Different software may use files with the same extension for different types of data.

Camera RAW Image File (Epson)

Camera RAW Image File (Epson) files are unprocessed image files produced by Epson digital cameras, most notably the Epson R-D1 and R-D1s rangefinder models. These files store the raw data output directly from the camera's sensor before any in-camera processing like white balance, color correction, or sharpening. The format gives photographers full control over how the image is developed, allowing adjustments to exposure, color balance, contrast, and other parameters without degrading the original data.

After capture, ERF files are intended to be opened and processed using raw‐image editing or conversion tools. Commonly they are first imported into software such as Epson's own PhotoRAW or compatible raw converters (e.g. Adobe's tools), where one applies the desired adjustments, then exported to more common formats like TIFF or JPEG for sharing, printing, or further editing. Because the files preserve sensor data, they tend to be large and are not typically user-viewable at full resolution without specialized software.

On a technical level, the format is based on the TIFF/EP standard. Within the file, CFA (Color Filter Array) sensor data is stored in a primary SubIFD off of the first IFD (Image File Directory), with Exif metadata in an ExifIFD associated with IFD0. Thumbnail data appears as an RGB thumbnail in IFD0. The CFA image data is byte-packed and the Compression tag in the CFA subIFD is set to 32769. The internal signature begins with the TIFF/EP byte order mark ("MM" for big-endian or "II" for little), followed by the TIFF magic number 0x2A, then other Epson-specific identifiers including "EPSON DSC Picture SEIKO EPSON CORP. R-D1".

ERF opener for Windows

We have identified 3 ERF openers that are compatible with this specific type of ERF file.

Compucon EOS Design Format

We know that one ERF format is Compucon EOS Design Format. We have not yet analyzed in detail what these files contain and what they are used for. We're working on it.

Various apps that use files with this extension

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

Help us help others

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