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More => Old Versions => Media Center 14 (Development Ended) => Topic started by: stevenf on October 04, 2009, 08:40:54 am

Title: FLAC Encoding
Post by: stevenf on October 04, 2009, 08:40:54 am
Hi there

I've just encoded a cd using the FLAC Encoder, assuming that it was a lossless format but have discovered that it appears not to be.

Example:

Moody Blues - Journey Through Time CD

bitrate: 1440 for all songs

Total Size: 648.7 mb

Moody Blues - Journey Through Time FLAC Encoded

Bitrate: between 706 - 910

Total Size: 382.0 mb

Is this right, or have i done something wrong. I assumed that if a cd was ripped in the flac format the bitrate would be 1440?

Any help would be appreciated.

Thanks

Stevenf
Title: Re: FLAC Encoding
Post by: AoXoMoXoA on October 04, 2009, 09:04:12 am
You are correct in your understanding of FLAC as Lossless, however you misunderstand the functionality of FLAC when expecting to have the resulting FLAC file the same size and bitrate as the wav.

While Lossless, FLAC does use compression. But unlike a lossy format (like mp3) it does NOT remove any information, simply squeezing it into a smaller package by fitting all the "chunks" tightly together.  Think of a document file that has been made into a Zip or Rar file, it becomes smaller when compressed but opens into the same as it's original prior to compression.

Simply put, it is like a wav file with the extra airspace removed and repackaged to hold tags. (When playing I believe it gets decompressed back into wav before going to your soundcard.)

If you were to transcode the FLAC file back into a Wav file, it would match the original ripped wav once again.
Title: Re: FLAC Encoding
Post by: Alex B on October 04, 2009, 09:15:03 am
In addition to what AoXoMoXoA said,

The bitrate is simply a measure of size. It tells how many bits of disk space or bandwidth gets used during the given time interval (in this case kilobits per one second of audio). It doesn't tell anything about the used compression method and its possible losslessness. A compressed file is smaller than an uncompressed file and thus also the bitrate is smaller. The compression/decompression process can be lossless, like when the FLAC format is used (... or Monkey's Audio, WavPack Lossless and WMA Lossless).
Title: Re: FLAC Encoding
Post by: stevenf on October 04, 2009, 10:14:13 am
Fantastic explanation, thanks guys, that has really cleared things up. I'll be encoding everyting to flac now. Once agan, thanks.

Stevenf