Re: Magnifying JPEGs viewed in Safari?

In article <noemailhere-C524CB.21375307052008@[EMAIL PROTECTED]
>,
 The NewGuy <noemailhere@[EMAIL PROTECTED]
> wrote:

> > If you zoom a picture up from its native px size, it will soon be 
> > noticeably fuzzier. 
> 
> If you start with low resolution of course.  Start with high quality and

> it will just keep giving you more and more detail.

I don't really know what you mean I am afraid. I can guess though. But I 
will wait. If you are preparing a pic for a web page, best practice is 
usually to prepare it to the px size you want. Quality has nothing to do 
with the issue of blurring in the sense that a fixed px size pic will 
blur on enlargement (whether because the res goes down as the pxs are 
spread out or because they are added to by the browser - there are no 
very very good algorithms for this, for good reasons) 

> Well obviously if you start with a pic that is 300 x 200 and zoom to 
> 800% its going to be a blur.  Start with 3000 x 2200 

It is not good to even begin talking about a pic this size for a web 
page for normal public consumption. 

But, to be fair to you, you are touching on a technique that I have 
[played with myself. Now and then I want a pic to be able to grow and 
shrink with the text size. Under modest text size changes, this can work 
very well at least on Mac machines (I have experienced poor results on 
Windows which have tempered my enthusiasm and am still investigating 
this.). 

To make this work, and for all browsers, not just special zooming ones 
like Opera, it is best to prepare the pics to be good for folk with 
eyesight that needs a few 'notches up' of the text size. So you prepare 
a pic, to give rough figures, that will normally be seen at 300px wide 
at wider. In other words, you get your master pic, a huge one from a 
modern camera and you size it to perhaps 500px. You then specify the 
dimensions of the pics in the html in em units and not px. This involves 
a bit of trial and error if you want to give both horiz and vert 
dimensions. 

This works reasonable well because algorithms for reducing pics work 
nicely cf to the opposite (and for good reason).

> 
> > There is no 
> > special font maths involved here. The font is treated as just a set of

> > pxs and is enlarged by a crude(r) browser algorithm to be bigger. The 
> > blur is then the general blur that results from machines not knowing 
> > what is im****tant and what not when blowing up pics. Even a classy
image 
> > program like Photoshop does poorly when blowing up a pic, browsers are

> > not any better.
> > 
> > Roughly this.
> 
> Maybe you need a better monitor.   :)

No. I have the best. A misunderstanding corrected in my last post. I 
apologise yet again. Modern Opera is quite sophisticated.

-- 
dorayme