Philip, a forensic officer, was tasked with investigating a crime scene.

The UNIX/Linuxddutility performs abit-by-bit (sector-by-sector) copyfrom an input device (such as a physical disk) to an output target (another device or a flat file). In digital forensics guidance, this type of output is known as araw (bitstream) imagebecause it captures the exact sequence of bytes from the source media without embedding structured case metadata, compression, or container features by default. The resulting file is often referred to as a “dd image” and may use extensions like.ddor.img, but the key point is theformat is raw: it represents a straightforward byte-for-byte representation of the original storage, including allocated data, unallocated space, slack space, and file system structures.

By contrast,AFFandAFF4are forensic container formats designed to store evidence data along with metadata (and often support features such as chunking, compression, and richer integrity structures). “Proprietary format” refers to vendor-specific containers (for example, formats created by certain commercial forensic tools) rather than the generic output produced by dd. Since Philip specifically usedddto create bit-by-bit disk images, the extracted acquisition image format isRaw Format (A).