AC3
audio/ac3
Magic Bytes
Offset: 0
0B 77
AC-3, commonly known as Dolby Digital, is a lossy audio compression format developed and maintained by Dolby Laboratories for multi-channel sound reproduction. It serves as the standard for digital television broadcasts, DVD media, and cinematic audio distribution requiring standardized storage of surround sound data. The format is fundamentally safe for playback, although it is now considered a legacy technology increasingly replaced by the modern Dolby Digital Plus (E-AC-3) codec.
Validation Code
How to validate .ac3 files in Python
Python
def is_ac3(file_path: str) -> bool:
"""Check if file is a valid AC3 by magic bytes."""
signature = bytes([0x0B, 0x77])
with open(file_path, "rb") as f:
return f.read(2) == signatureHow to validate .ac3 files in Node.js
Node.js
function isAC3(buffer: Buffer): boolean {
const signature = Buffer.from([0x0B, 0x77]);
return buffer.subarray(0, 2).equals(signature);
}
Go
func IsAC3(data []byte) bool {
signature := []byte{0x0B, 0x77}
if len(data) < 2 {
return false
}
return bytes.Equal(data[:2], signature)
}API Endpoint
GET
/api/v1/ac3
curl https://filesignature.org/api/v1/ac3