On 15 Dec, [EMAIL PROTECTED] wrote:
> Hi All,
> 
>              What does 'Xing TOC' signify?. I also want to
> know why there is a header called XingHeader. Is it same
> as MPEG header?. Can anybody through some light on
> it?.

The Xing header is only used for VBR files. To seek to a percent, say
50%, in a constant bitrate file all the player needs to do is to seek to
50% in the actual MP3 file, find the next frame and continue playing
from there. All the frames are roughly the same size making seeking
easy.

With variable bitrate files, let's use an example: Assume you have a
file that is silence for 1 minute, and music for 1 minute. The VBR
encoder will encode the song at a low bitrate for the first minute and
then a higher bitrate for the second minute. The player cannot just
randomly seek to 50% and expect to find the spot where the music starts.

The Xing header is designed to overcome just that. It provides the
player with 100 seek points in the file. So if the player wants to seek
to 50%, it would look into the 50th slot in the Xing header, and from
the data in the slot the player could figure out where to seek to.

If that doesn't cover it, let me know what I can elaborate on.


--ruaok         Freezerburn! All else is only icing. -- Soul Coughing

Robert Kaye -- [EMAIL PROTECTED]  http://moon.eorbit.net/~robert


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