JFI
image/jpeg
Magic Bytes
Offset: 0
FF D8 FF
JFI is a raster image format developed by the Joint Photographic Experts Group that adheres to the JPEG File Interchange Format (JFIF) standard. This file type is primarily utilized for storing compressed digital photographs and complex web graphics, enabling efficient data transmission across networks. While the underlying encoding remains universally supported and safe for viewing, the specific JFI file extension is considered a legacy naming convention that has been largely superseded by the more common JPG identifier.
Validation Code
How to validate .jfi files in Python
Python
def is_jfi(file_path: str) -> bool:
"""Check if file is a valid JFI by magic bytes."""
signature = bytes([0xFF, 0xD8, 0xFF])
with open(file_path, "rb") as f:
return f.read(3) == signatureHow to validate .jfi files in Node.js
Node.js
function isJFI(buffer: Buffer): boolean {
const signature = Buffer.from([0xFF, 0xD8, 0xFF]);
return buffer.subarray(0, 3).equals(signature);
}
Go
func IsJFI(data []byte) bool {
signature := []byte{0xFF, 0xD8, 0xFF}
if len(data) < 3 {
return false
}
return bytes.Equal(data[:3], signature)
}API Endpoint
GET
/api/v1/jfi
curl https://filesignature.org/api/v1/jfi