[Coco] VEF Format Details

[Joel Ewy]

Willard Goosey wrote:
> On Fri, Jan 01, 2010 at 06:24:25PM -0600, Joel Ewy wrote:
>   
>> Hey all,
>>
>> Does anybody know if it is possible to make a .VEF file with a number of 
>> rows <>200?  More properly, is there a way to specify the number of 
>> lines in the header, and do programs like 'view' understand that?  
>> Specifically, does the standard support 192-line or 225-line images?
>>     
>
> Unfortunately, no.  I've got the closest thing to a standard
> specificiation at http://www.sdc.org/~goosey/vef.format.txt I typed it
> in from the MVCanvas docs by Mike Haaland of Hyper-Tech Software,
> 1989, updated 03/22/90.
>
>   

Thanks, Willard.

JCE

> Briefly, the VEF header is:
> A two byte VEF Header.  Header Values are in Hexadecimal
>
> Standard   Squashed  Screen Type  Screen size   Colors
> -------------------------------------------------------
> 0000       8000       08          320x200       16
> 0001       8001       07          640x200        4
> 0003       8003       06          320x200        4
> 0004       8004       05          640x200        2
>
> 16 bytes palette information
>
> Picture Data:
>
> I haven't had any trouble from other programs with short (24-line)
> VEFs. 
>
> View does have a command-line option to specify how many lines at the
> start of the file to skip, but I don't know if that would get you to
> the bottom part of a 225-line VEF or not.
>
> For 192-line screens, it seems the standard is to ignore the first 8
> lines of the VEF.
>
> Good luck!
>
> Willard
>