Hi Thorsten,
----- Original Message -----
From: "Thorsten Behrens" <[EMAIL PROTECTED]>
Newsgroups: openoffice.dev
To: <[email protected]>
Sent: Tuesday, May 17, 2005 5:38 PM
Subject: Re: [dev] question about improving the speed of openning .ppt file
> "jiangdongjin" <[EMAIL PROTECTED]> writes:
>
> > To my opinion, OOo impress opens .ppt file slower because of:
> > 1. It imports all contents before displays, but MS Powerpoint only
> > imports those needed;
> > 2. It create too many temp files for those pictures embeded in
> > slide pages, but MS Powerpoint do nothing about this.
> >
> Hi jiangdongjin,
>
> as you've found out by yourself, not streaming out the images to temp
> files hogs huge amounts of memory (and is therefore not an
> option).
>
> Your first item is actually the crucial point here: as our PPT import
> is just that, an import, we really have to fully read the file
> content. This is because our own, internal representation of the
> document content (the 'model') must be complete before anything can be
> displayed. There are currently no mechanisms to lazy-load only the
> first slide, and the remainder only on demand.
>
As I mentioned :
OOo impress imports all contents before displays, but MS Powerpoint only
imports those needed;
I have tried to change the synchronous load mechanism but I failed :)
So many things I need to know and change.
I found when open my test .ppt file(contains many jpg or bmp pictures), the
most time-wasted points are those functions to load picture.
i.e.
ImportGIF(...)
ImportPNG(...)
ImportJPEG(...)
ImportXBM(...)
......
If I omit these functions, My test .ppt file opened as fast as MS
Powerpoint(maybe 1-2 seconds slower), but all my pictures are missing.
So my plan is, in the load phase, I only load some basic infomation like width
and height of the picture(I think only these are necessary for formatting),
then display.After that if I really need some pictures(display or operation), I
import it from input stream.
Is my method feasible? Thanks!
best regards,
jiangdongjin
