[LINK] Guidelines for Digital Repositories, Canberra, 27 July

[Kim Holburn]

On 2006 Jul 21, at 11:24 AM, Karl Auer wrote:
> On Fri, 2006-07-21 at 10:29 +1000, Kim Holburn wrote:
>> As I understand it in general, digital archiving usually involves
>> uncompressed data with all the bits present.  While you might include
>> compressed versions the base data is uncompressed.
>
> The problem is that compression ain't compression.

Yes but that's not the only problem.  The other problem from a  
archiving point of view is that over a long time you may lose the odd  
bit.  In an uncompressed file you just lose that odd bit and that's  
that but in a compressed file you are quite likely to lose all the  
data after the lost bit.

> Compression to us programmers means reducing the amount of data  
> using a
> completely reversible encoding, so that the result after decompression
> is identical to the original uncompressed data.
>
> Compression to video people means *throwing data away* to reduce the
> size of the data. It is one of the huge sadnesses of early television,
> and it continues to this day, that vast amounts of irreplaceable video
> are being discarded during "archiving". Putting film on video also  
> loses
> huge amounts of data, as the resolution of film is vastly higher than
> video.

--
Kim Holburn
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