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Re: CBF - long discussion


I do not want to answer specifically to any point mentioned in Nick and Syd mail. Just a general comment.

HTTP  protocol uses 8 bits and is not restricted to ASCII characters. Thus I see no future in trying to encode as ASCII characters an information which is not. 

More important than that: assume we necode as ASCII characters the binary information which is contained in an image. We would still face the problems they mention since it would just be a way of coding.

- 1 - It is true that big and little endian is a problem. How do we avoid this with ASCII encoding.

- 2 - It is true that floating point numbers representation is not always IEEE and may change in the future. ASCII encoding will not prevent from this kind of difficulty.

I could find other arguments against ASCII encoding but my view is just that is not acceptable. The idea of using something else than binary for images is just unacceptable. To use the same words it is very untechnical to suggest this.

Data have to be contained in one single file. Users are not computer people. The organization that most scientists use to store their files is just a mess. They seldom use the full advantage of a hierarchical organization of directories. Thus how can we imagine that they will correctly manipulate a paar of files. This is just the view of theoreticians, not of people creating images. 

I am not personnaly satisfied with all the details of the proposed format but I do not see any major difficulty since I believe we will need a library of functions to extract relevant information. I do not see any difficulty in the future to enhance, modify and adapt these functions when computers will evolve.

Thus my conclusion is the following:

If no agreement is acceptable for COMCIF people, let us defien a complete new format with or without STAR format since we will use binary files.
May be we should start the discussion again without this restriction..
With best regards,


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       :    Yves EPELBOIN                                          :
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