Re: Transfer time

Chris Marrin ([email protected])
Sun, 21 May 1995 15:06:28 -0700

On May 20, 3:08pm, Nathan J. Strange wrote:
> Subject: Transfer time
>
> It seems to me that everyone is going to want detailed and large
> virtual worlds.. just the kind that love to eat up bandwidth
> for vrml 1.1 how about adding a mime type for some sort of simple
> compresion. .wrc files could be this new type.... We could get a lot
of
> compression just by translating all of the commands into 1 or 2 byte
> sequences, chuckin comments and whitespace and making everything binary
>
> This seems (on the surface at least) easy to implement and .wrc files
> ought to be much smaller than .wrl files... and a parser to make .wrl
> files into .wrc files could be distrbuted...

The standard method (using gzip and appending a .gz to the .wrl file)
already gets 8:1 compression on most files. Gzip is probably finding
about a million instances of "Separator" and reducing it to a single byte
and finding lots of numbers and compressing the hell out of those. I
think it would be tough to beat this by much with a specific binary
format. A binary format would speed decompression (because it wouldn't
need any) and maybe parsing but I'm not sure it would be a big win...

-- 
chris marrin      Silicon      http://www.sgi.com/Products/WebFORCE/WebSpace
(415) 390-5367    Graphics  ," http://reality.sgi.com/employees/cmarrin/
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