# Amiga Disk image File (OFS+INTL+DIRC)

> file format

**Wikidata**: [Q105857908](https://www.wikidata.org/wiki/Q105857908)  
**Source**: https://4ort.xyz/entity/amiga-disk-image-file-ofs-intl-dirc

## Summary
Amiga Disk image File (OFS+INTL+DIRC) is a specific Amiga disk-image file format variant used to store the contents and structure of an Amiga disk volume. It is a variant of the generic Amiga Disk image File and is commonly identified by the .adf file extension and a 4-byte signature 44 4F 53 06 at the start of the file.

## Key Facts
- Instance of: disk image — a computer file that contains the contents and structure of a disk volume.  
- Based on: Amiga Disk image File (generic).  
- File extension: .adf.  
- File format identification pattern (magic number): 44 4F 53 06 (hex) at the beginning of the file (offset 0).  
- Described at: https://en.wikipedia.org/wiki/Amiga_Disk_File.  
- Wikidata description: file format.  
- Name indicates a variant labeled "OFS+INTL+DIRC" within the Amiga Disk image File family.  
- Format identification pattern is specified in hexadecimal and applies at the beginning of the file.

## FAQs
### Q: What is Amiga Disk image File (OFS+INTL+DIRC)?
A: It is a variant of the Amiga disk-image file format used to represent the contents and structure of an Amiga disk volume. It is tied to the generic Amiga Disk image File family and typically uses the .adf extension.

### Q: How can I identify this file format?
A: The format can be identified by the 4-byte signature 44 4F 53 06 (hex) located at the beginning of the file (offset 0). The .adf file extension is commonly associated with Amiga disk images.

### Q: Is this a separate file type from the generic Amiga Disk image File?
A: No. It is a variant based on the generic Amiga Disk image File format, indicated by the name "OFS+INTL+DIRC" to distinguish this specific variant within that family.

## Why It Matters
Amiga Disk image File (OFS+INTL+DIRC) matters because it is a defined disk-image variant within the Amiga ecosystem for preserving the exact contents and structural metadata of Amiga disk volumes. Disk images provide a portable, bit-for-bit representation of a disk, allowing software preservation, emulation, and transfer without requiring the original physical media. The presence of a clear identification pattern (44 4F 53 06 at file start) makes automated detection and tool support straightforward. Using a standard extension (.adf) and a known signature helps archivists, emulation projects, and software tools recognize and handle this variant reliably. As a member of the Amiga Disk image File family, it fits into established workflows for managing Amiga disk data and aids compatibility across utilities that work with Amiga disk images.

## Notable For
- Having a distinct 4-byte signature 44 4F 53 06 (hex) at the beginning of the file for format detection.  
- Being explicitly based on the generic Amiga Disk image File format, making it part of the established Amiga disk-image family.  
- Using the widely recognized .adf file extension associated with Amiga disk images.  
- Carrying the variant label "OFS+INTL+DIRC," which identifies its specific structure within Amiga disk-image types.

## Body

### Overview
- Amiga Disk image File (OFS+INTL+DIRC) is a named variant of the Amiga Disk image File family.  
- It represents a disk image format for Amiga systems.  
- The format is classified as a file format and as a disk image type.

### File identification
- Magic number (signature): 44 4F 53 06 (hex).  
- Signature location: beginning of file (offset 0).  
- The signature is specified in hexadecimal notation.

### File extension
- Common extension: .adf.  
- The .adf extension is associated with Amiga Disk image Files in general.

### Relationship to generic Amiga Disk image File
- This variant is based on the Amiga Disk image File (generic).  
- The variant label "OFS+INTL+DIRC" distinguishes it within the generic family.

### Classification and references
- Instance type: disk image (computer file containing the contents and structure of a disk volume).  
- External description available at: https://en.wikipedia.org/wiki/Amiga_Disk_File.  
- Wikidata describes the entity simply as a file format.

## References

1. [TrID](https://mark0.net/soft-tridscan-e.html)