Re: Check / verify and test quality of burned CD/DVD's
On Thu 15 July 2004 16:50, Ashish Rangole wrote:
> I usually calculate the md5sum of the iso image before
> writing it to the disc. After successful write I use
> readcd to read the iso image back, calculate its md5sum
> and compare.
But that doesn't give you any quality information does it? And that
was what you were asking about?
From the readcd manpage:
Scans the whole CD or the range specified by the
sectors=range for C2 errors. C2 errors are errors
that are uncorrectable after the second stage of
the 24/28 + 28/32 Reed Solomon correction system at
audio level (2352 bytes sector size). If an audio
CD has C2 errors, interpolation is needed to hide
the errors. If a data CD has C2 errors, these
errors are in most cases corrected by the ECC/EDC
code that makes 2352 bytes out of 2048 data bytes.
The ECC/EDC code should be able to correct about
100 C2 error bytes per sector.
If you find C2 errors you may want to reduce the
speed using the speed= option as C2 errors may be a
result of dynamic unbalance on the medium.
If it finds a lot of C2 errors, quality is low, if not, quality is
Unless I misunderstood your question...
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