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More => Old Versions => Media Center 11 (Development Ended) => Topic started by: Alweb on May 11, 2004, 11:33:29 am

Title: Burning CDs
Post by: Alweb on May 11, 2004, 11:33:29 am

Hi

For rip a Cd I select tracks that sum 696 Mb size. My media is TDK 700Mb size. MC return a message that was 19Mb over the media size.
What's happing?  ?

Alweb

Title: Re:Burning CDs
Post by: LonWar on May 11, 2004, 11:57:24 am

I have often wondered that...

Title: Re:Burning CDs
Post by: twriter on May 11, 2004, 01:15:13 pm

Quote from: Alweb on May 11, 2004, 11:33:29 am

For rip a Cd I select tracks that sum 696 Mb size. My media is TDK 700Mb size. MC return a message that was 19Mb over the media size.
What's happing?  ?

While I don't remember the technical specifics (and I don't want to Google to track it down, there are two issues (I think):

First, there is some overhead when writng a CD. That overhead is in addition to the total amount of data. It's not a large amount, but it's there.

Second (and I'm not sure about this one), data files may be written to block boundaries, like on a hard disk. If so, then the total space needed is am=lmost always a little arger than the total of the data. I don't think the blocks on a CD are that arge, so the extra space typicall would be just a few KB.

I've seen information that some CD writers will write a little extra data to a CDR, suggesting that "real" capacity is a little larger than stated/rated capacity. Some CD buring software will allow you to attempt to write more. But this is risky: even if you can write a little more than capacity, there is no guarantee that CD players will be able to read the data.

Title: Re:Burning CDs
Post by: JohnT on May 12, 2004, 08:32:32 am

When writing a data disk, there needs to be room for a leadin and leadout area. Since MC always writes a multi-session type disk, it will also write a leadin for the next session (if there's room).  So.. MC adds the size of 1 leadout and 2 leadins to the data you selected. If I remember correctly, the leadin is 60 seconds, the leadout is 30 seconds, so MC adds 120 seconds which equals about 21MB of overhead. Also, the rated capacity is off sometimes, so a "700MB" disk may only hold 698 or 699MB. Also, there needs to be room for directory space which can add up to a meg or two if you are writing a large number of small files.