DPK

A .dpk file is a simple archive format without compression. The format appears to be proprietary and specific to the ''Bunny Pro. Das2'' visual novel software for Windows.

See also NAS.

Specification
The format comprises a header and payload.

The header includes the magic bytes "PA" followed by the number of entries and total file size. Each file entry in the header is then designated by a null-padded string of 16 characters (ASCII) and the length of the file

Files in the payload are stored in the order in which the entry appears, and can be extracted by reading the number of bytes corresponding to the length of the file.

Source
The following source can be used to extract  files using Python.

import struct import argparse import os

header_format = '2shi' header_size = struct.calcsize(header_format)

entry_format = '16si' entry_size = struct.calcsize(entry_format)

def unpack(fileName): BASE_NAME = os.path.splitext(os.path.basename(fileName))[0]

os.mkdir(BASE_NAME)

with open(fileName, 'rb') as f:		[magic_bytes, file_count, package_size] = struct.unpack(header_format, f.read(header_size))

assert magic_bytes == b'PA' assert file_count > 0 assert package_size > 0

FILES = []

for i in range(0, file_count, 1): [file_name, file_size] = struct.unpack(entry_format, f.read(entry_size)) FILES.append([				file_name.decode("ascii").rstrip('\x00'),				file_size			]) for file_name, file_size in FILES: file_data = bytearray(f.read(file_size))

with open(os.path.join(BASE_NAME, file_name), 'wb') as new_file: new_file.write(file_data)

if __name__ == '__main__': parser = argparse.ArgumentParser(                   prog = 'dpk Unpacker',                    description = 'Unpacks .dpk packages') parser.add_argument('INPUT_FILE') args = parser.parse_args unpack(args.INPUT_FILE)

Sample files

 * Corsage → ...Disc 1.iso → WAV.DPK