DRC
video/x-dirac
Magic Bytes
Offset: 0
4F 67 67 53 00 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 2E 42 42 43 44
Dirac (DRC) is a wavelet-based video compression format developed by the British Broadcasting Corporation (BBC). It was engineered to facilitate video transmission and storage across a range of resolutions, from internet streaming to ultra-high-definition television. Although largely superseded by contemporary standards such as H.264 and AV1, this legacy format is considered safe and was historically significant for providing a patent-free alternative for media compression.
Validation Code
How to validate .drc files in Python
Python
def is_drc(file_path: str) -> bool:
"""Check if file is a valid DRC by magic bytes."""
signature = bytes([0x4F, 0x67, 0x67, 0x53, 0x00, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x42, 0x42, 0x43, 0x44])
with open(file_path, "rb") as f:
return f.read(32) == signatureHow to validate .drc files in Node.js
Node.js
function isDRC(buffer: Buffer): boolean {
const signature = Buffer.from([0x4F, 0x67, 0x67, 0x53, 0x00, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x42, 0x42, 0x43, 0x44]);
return buffer.subarray(0, 32).equals(signature);
}
Go
func IsDRC(data []byte) bool {
signature := []byte{0x4F, 0x67, 0x67, 0x53, 0x00, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x2E, 0x42, 0x42, 0x43, 0x44}
if len(data) < 32 {
return false
}
return bytes.Equal(data[:32], signature)
}API Endpoint
GET
/api/v1/drc
curl https://filesignature.org/api/v1/drc