Audio
Free Lossless Audio Codec is a audio format commonly identified by .flac. Use the listed signatures, MIME types, and structure notes to validate files beyond the extension.
66 4C 61 43 fLaCSIGNATURE = bytes.fromhex("664c6143")
OFFSET = 0
def is_flac(path: str) -> bool:
with open(path, "rb") as f:
f.seek(OFFSET)
head = f.read(len(SIGNATURE))
return head == SIGNATUREconst SIGNATURE = [0x66, 0x4c, 0x61, 0x43];
const OFFSET = 0;
// bytes: a Uint8Array / Buffer holding the start of the file
export function isFlac(bytes) {
return SIGNATURE.every((byte, i) => bytes[OFFSET + i] === byte);
}package fileid
import "bytes"
var isflacSignature = []byte{0x66, 0x4c, 0x61, 0x43}
const isflacOffset = 0
func IsFlac(b []byte) bool {
end := isflacOffset + len(isflacSignature)
if len(b) < end {
return false
}
return bytes.Equal(b[isflacOffset:end], isflacSignature)
}const SIGNATURE: &[u8] = &[0x66, 0x4c, 0x61, 0x43];
const OFFSET: usize = 0;
fn is_flac(bytes: &[u8]) -> bool {
bytes.get(OFFSET..OFFSET + SIGNATURE.len()) == Some(SIGNATURE)
}<?php
$signature = "\x66\x4c\x61\x43";
$offset = 0;
function is_flac(string $bytes): bool {
global $signature, $offset;
return substr($bytes, $offset, strlen($signature)) === $signature;
}Free Lossless Audio Codec is used for playback, waveform processing, upload checks, duration handling, and bitrate validation. Short clips, silence, and ambient audio help expose player and conversion edge cases.
Media files can still stress decoders through corrupt metadata, extreme dimensions, long durations, or unusual chunks. Read size, dimensions, and duration before processing.
11 samples help test duration handling, playback startup, metadata reads, and download behavior.
1s Silence FLAC is a Free Lossless Audio Codec sample generated for file format testing. It can be used to test downloads, parsers, previews, and file type detection.
silence-1s.flacLake Waves FLAC 0.25s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 0.25s. It can be used to test downloads, parsers, previews, and file type detection.
01-lake-waves.flaca2a9abf98b984e8f4b75868424efe7e6a0259035199806bc360a218c5094e37fLake Waves FLAC 0.5s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 0.5s. It can be used to test downloads, parsers, previews, and file type detection.
02-lake-waves.flac4402cc654d9b53bd5d0da473444823a75a48804e523625bce9d8d3832700f159Lake Waves FLAC 1s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 1s. It can be used to test downloads, parsers, previews, and file type detection.
03-lake-waves.flac518668c05cc50be5eb561bc8bd7ba1b818eb03adfc84585b2aaf3e6ebd69f975Lake Waves FLAC 1.5s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 1.5s. It can be used to test downloads, parsers, previews, and file type detection.
04-lake-waves.flac113dafd18746bca254946cce2677875514c1fe831966e197725641b719897326Lake Waves FLAC 2s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 2s. It can be used to test downloads, parsers, previews, and file type detection.
05-lake-waves.flac447e394320105cfd3638e6e0d044dcd601fc3b201b606162d26b5039f530d0d3Lake Waves FLAC 3s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 3s. It can be used to test downloads, parsers, previews, and file type detection.
06-lake-waves.flac5906188852edd4063e7617796db09fc91c039355214dc68952d35f2e43c31b4cLake Waves FLAC 4s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 4s. It can be used to test downloads, parsers, previews, and file type detection.
07-lake-waves.flac18d16d1cf1f35d06208a2c87e4a80bcab46dac2e288e3196792c39c4cb239c9cLake Waves FLAC 6s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 6s. It can be used to test downloads, parsers, previews, and file type detection.
08-lake-waves.flaca149d798b4b0c44869b064a8beb0a3ba85ff25e5dda4233c38c8029cdcdd4a2dLake Waves FLAC 8s is a Free Lossless Audio Codec sample based on Wikimedia Commons, 8s. It can be used to test downloads, parsers, previews, and file type detection.
09-lake-waves.flac647745114c8ea0a232150c686a315752efae6e57d0643466c6cb6c3e018fa4edNASA TV Audio FLAC is a Free Lossless Audio Codec sample based on NASA Image and Video Library, 2s. It can be used to test downloads, parsers, previews, and file type detection.
nasa-tv-audio.flac724ec58bb3b853bc43026ebebdd1ecfcf80d0f1e8e197bf22b43c5bfe503f1dfFree Lossless Audio Codec files begin with the byte signature 66 4C 61 43 ("fLaC"). Detect the format by reading these leading bytes rather than trusting the file extension alone.
The MIME type for Free Lossless Audio Codec is audio/flac.
Free Lossless Audio Codec files use the .flac extension. The extension is a convention only and does not guarantee the file contents, so combine it with signature and structure checks.