On May 12, 2010, at 9:24 AM, Nawal Kishor Mishra wrote:>
> Dear FLAC team,
> I have some fundamental doubts regarding FLAC encoder:
>
> 1) In FLAC encoder there is no option of specifying the bitrate. There is
something called compression-level. I believe that based on the nature of input
WAV file and compression-level chosen bitrate is coming into picture. As such
there is no user control on the bitrate. Is that correct?
> 2) In FLAC encoder I am also not seeing any option of specifying CBR or
VBR. I assume that by default FLAC encoder is VBR. Is that correct?
Hi Nawal,
1) There is no direct user control on the bitrate.
2) FLAC is VBR in the literal sense.
FLAC is a lossless encoder; it tries to use as few bits as possible while
preserving all audio information. This means that the bit-rate can't easily
be fixed: lossy encoders (eg. MP3, Vorbis, AAC) typically throw out additional
information until the target bit-rate is reached.
The compression-level for FLAC relates to flexibility in how the encoder can
represent the original audio without losing any information. There are normally
a lot of different ways to do this, and the compression-level essentially
indicates how much work the encoder should do while searching for the best
amongst them. (The more work, the more likely the encoder will find a better
representation of the audio, but with diminishing returns as more work is done.)
Cheers,
- Andrew