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<[email protected]> |
It worked perfectly. The only problem I have now is the following.
The PPM format has three line at the beginning such as:
P5
32 32
255
where P5 is the flag for binary greyscale
32 32 are the size of the image
255 number of greylevels
Just after that starts the binary part of the file that I can
generate following your good suggestion.
Now, how can I write, in the same file, the first three text line
followed by the binaries ones?
Massimo
Citando Salvador Pinto Abreu <[email protected]>:
> On Nov 1, 2012, at 11:30, [email protected] wrote:
>
>> I am trying to automatically generate PPM P5 files.
>> In order to write the binary part of the files, I am using
>>
>> put_code/1
>
> maybe, considering you are building a non-text file, you'd be better
> off having Prolog use a binary stream, in which case you'd be using
> the put_byte/1 built-in.
>
> consider this, for instance:
>
> 11:56:56$ gprolog
> GNU Prolog 1.4.1
> By Daniel Diaz
> Copyright (C) 1999-2012 Daniel Diaz
> | ?- open(foo, write, _FOO, [type(binary), alias(foo)]),
> set_output(foo),
> put_byte(0), put_byte(1), put_byte(2), put_byte(3),
> close(foo).
>
> (1 ms) yes
> | ?- halt.
>
> 11:57:05$ od -b foo
> 0000000 000 001 002 003
> 0000004
> 11:57:10$ ls -l foo
> -rw-r--r-- 1 spa staff 4B Nov 1 11:56 foo
> 11:57:19$
>
> hope this helps
> -salvador
>
>
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Massimo De Gregorio
Research Scientist
Istituto di Cibernetica "Eduardo Caianiello" - CNR
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