HighDots Forums  

How to resize <IMG> width absolute and height relative ?

HTML Writing HTML for the Web (comp.infosystems.www.authoring.html)


Discuss How to resize <IMG> width absolute and height relative ? in the HTML forum.



Reply
 
Thread Tools Display Modes
  #1  
Old   
Wladimir Borsov
 
Posts: n/a

Default How to resize <IMG> width absolute and height relative ? - 05-03-2004 , 07:11 AM






As well known for <IMG ...> tags in web pages a width and a height attribute can be
applied. What I want to do now is to fix the width for ALL the images on my web page
to exactly lets say 70 pixel regardless how big the originals are.

The height should be adjusted proportional so that the resulting thumbnail is not distorted.
But as far as I know there is no such attribute like

<IMG SRC=...... WIDTH=70 HEIGHT="Adjust proportional to Width"> ....

How can I solve this problem ?

As a second best solution I could accept if I could write percentage values:


<IMG SRC=..... WIDTH=50% HEIGHT=50%>

but this doesn't work too.

Wladimir


Reply With Quote
  #2  
Old   
Markus Ernst
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-03-2004 , 08:07 AM






"Wladimir Borsov" <wladimirb (AT) gmx (DOT) net> schrieb im Newsbeitrag
news:c75ct8$iqe$06$1 (AT) news (DOT) t-online.com...
Quote:
As well known for <IMG ...> tags in web pages a width and a height
attribute can be
applied. What I want to do now is to fix the width for ALL the images on
my web page
to exactly lets say 70 pixel regardless how big the originals are.

The height should be adjusted proportional so that the resulting thumbnail
is not distorted.
But as far as I know there is no such attribute like

IMG SRC=...... WIDTH=70 HEIGHT="Adjust proportional to Width"> ....

How can I solve this problem ?

Just don't write a height attribute, then AFAIK user agents should scale the
image proportionally.

But actually if this is applied to several images you should prefer to scale
them at the server side, otherwise you send much too much data to the
client.

HTH
Markus




Reply With Quote
  #3  
Old   
Mitja
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-03-2004 , 09:29 AM



Wladimir Borsov <wladimirb (AT) gmx (DOT) net>
(news:c75ct8$iqe$06$1 (AT) news (DOT) t-online.com) wrote:
Quote:
As well known for <IMG ...> tags in web pages a width and a height
attribute can be applied. What I want to do now is to fix the width
for ALL the images on my web page
to exactly lets say 70 pixel regardless how big the originals are.

The height should be adjusted proportional so that the resulting
thumbnail is not distorted. But as far as I know there is no such
attribute like

IMG SRC=...... WIDTH=70 HEIGHT="Adjust proportional to Width"> ....

How can I solve this problem ?
<img width="70" SRC="...">

Quote:
As a second best solution I could accept if I could write percentage
values:


IMG SRC=..... WIDTH=50% HEIGHT=50%

but this doesn't work too.

Wladimir




Reply With Quote
  #4  
Old   
nice.guy.nige
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-03-2004 , 09:50 AM



While the city slept, Wladimir Borsov <wladimirb (AT) gmx (DOT) net> feverishly typed:

Quote:
As well known for <IMG ...> tags in web pages a width and a height
attribute can be applied. What I want to do now is to fix the width
for ALL the images on my web page
to exactly lets say 70 pixel regardless how big the originals are.

The height should be adjusted proportional so that the resulting
thumbnail is not distorted. But as far as I know there is no such
attribute like

IMG SRC=...... WIDTH=70 HEIGHT="Adjust proportional to Width"> ....
You can use a server-side solution, such as PHP to do the maths. Off the top
of my head, if you know the original image width and heght (if not, no
problems as you can get them using PHP) something like the following should
work;

<? php

$desiredwidth = 70;
$originalwidth = 100; // replace originalwidth and originalheight with
whatever the image dimensions are...
$originalheight = 200; // ... or find a better way of getting them!

$ratio = $originalwidth / $desiredwidth;
$desiredheight = $originalheight / $ratio;

print("<img src=\"whatever.jpg\" width=\"$desiredwidth\"
height=\"$desiredheight\" alt=\"whatever\">\n");
?>

I haven't thoroughly checked this, so the maths may be wrong! But it still
shows a way to do it.

Remember, though, that if an original image is smaller than 70 pixels wide,
then this may result in distortion of the image as it will be stretched.
Remember also that this is a bad way to make thumbnails of large images, as
the full size image file still has to be loaded, regardless of how small you
are making it appear on the screen.

Hope that helps,
Nige

--
Nigel Moss.

Email address is not valid. nigel (AT) nigenetDOG (DOT) org.uk. Take the dog out!
http://www.nigenet.org.uk | Boycott E$$O!! http://www.stopesso.com
In the land of the blind, the one-eyed man is very, very busy!




Reply With Quote
  #5  
Old   
Stan Brown
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-03-2004 , 10:01 AM



"Wladimir Borsov" <wladimirb (AT) gmx (DOT) net> wrote in
comp.infosystems.www.authoring.html:
Quote:
As well known for <IMG ...> tags in web pages a width and a height attribute can be
applied. What I want to do now is to fix the width for ALL the images on my web page
to exactly lets say 70 pixel regardless how big the originals are.

The height should be adjusted proportional so that the resulting thumbnail is not distorted.
But as far as I know there is no such attribute like

IMG SRC=...... WIDTH=70 HEIGHT="Adjust proportional to Width"> ....

How can I solve this problem ?
In some (most?) browsers, leave off the height and it will be
adjusted proportionally.

But this is a bad thing to do. Why impose the penalty on the user of
downloading a larger picture, then not let her see it? If you want
your pictures to be 70px wide, crop them yourself before uploading.

<img> width and height should always match the actual width and
height of the image.

--
Stan Brown, Oak Road Systems, Cortland County, New York, USA
http://OakRoadSystems.com/
HTML 4.01 spec: http://www.w3.org/TR/html401/
validator: http://validator.w3.org/
CSS 2 spec: http://www.w3.org/TR/REC-CSS2/
2.1 changes: http://www.w3.org/TR/CSS21/changes.html
validator: http://jigsaw.w3.org/css-validator/


Reply With Quote
  #6  
Old   
Sid Ismail
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-03-2004 , 01:20 PM



On Mon, 3 May 2004 14:11:20 +0200, wladimirb (AT) gmx (DOT) net (Wladimir Borsov)
wrote:

: As well known for <IMG ...> tags in web pages a width and a height attribute can be
: applied. What I want to do now is to fix the width for ALL the images on my web page
: to exactly lets say 70 pixel regardless how big the originals are.
:
: The height should be adjusted proportional so that the resulting thumbnail is not distorted.
: But as far as I know there is no such attribute like
:
: <IMG SRC=...... WIDTH=70 HEIGHT="Adjust proportional to Width"> ....
:
: How can I solve this problem ?


Have only width=70. Remove height altogether. You'll get what you want.

Sid


Reply With Quote
  #7  
Old   
mscir
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-03-2004 , 10:02 PM



Wladimir Borsov wrote:

Quote:
What I want to do now is to fix the width for ALL the images on my web page
to exactly lets say 70 pixel regardless how big the originals are.
snip

I'm not sure about browser compatibility, this works on my IE6, Netscape
7.1, Firefox 0.8:

function resizepics(w,h){
var p = document.getElementsByTagName('img');
for (var i=0; i<p.length; i++){
p[i].style.width=w;
p[i].style.height=h;
}
}

Mike



Reply With Quote
  #8  
Old   
Markus Ernst
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-04-2004 , 07:05 AM



"nice.guy.nige" <nigel_moss (AT) deadspam (DOT) com> schrieb im Newsbeitrag
news:c75m9f$ikasc$1 (AT) ID-112325 (DOT) news.uni-berlin.de...
Quote:
While the city slept, Wladimir Borsov <wladimirb (AT) gmx (DOT) net> feverishly
typed:

As well known for <IMG ...> tags in web pages a width and a height
attribute can be applied. What I want to do now is to fix the width
for ALL the images on my web page
to exactly lets say 70 pixel regardless how big the originals are.

The height should be adjusted proportional so that the resulting
thumbnail is not distorted. But as far as I know there is no such
attribute like

IMG SRC=...... WIDTH=70 HEIGHT="Adjust proportional to Width"> ....

You can use a server-side solution, such as PHP to do the maths. Off the
top
of my head, if you know the original image width and heght (if not, no
problems as you can get them using PHP) something like the following
should
work;

? php

$desiredwidth = 70;
$originalwidth = 100; // replace originalwidth and originalheight with
whatever the image dimensions are...
$originalheight = 200; // ... or find a better way of getting them!

$ratio = $originalwidth / $desiredwidth;
$desiredheight = $originalheight / $ratio;

print("<img src=\"whatever.jpg\" width=\"$desiredwidth\"
height=\"$desiredheight\" alt=\"whatever\">\n");
?

I haven't thoroughly checked this, so the maths may be wrong! But it still
shows a way to do it.

Remember, though, that if an original image is smaller than 70 pixels
wide,
then this may result in distortion of the image as it will be stretched.
Remember also that this is a bad way to make thumbnails of large images,
as
the full size image file still has to be loaded, regardless of how small
you
are making it appear on the screen.
If you suggest the serverside solution I would suggest to use PHP to
actually resize the image file, not just the HTML code...

--
Markus




Reply With Quote
  #9  
Old   
Harlan Messinger
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-04-2004 , 09:32 AM




"mscir" <mscir (AT) access4less (DOT) com.net.org.uk> wrote

Quote:
Wladimir Borsov wrote:

What I want to do now is to fix the width for ALL the images on my web
page
to exactly lets say 70 pixel regardless how big the originals are.
snip

I'm not sure about browser compatibility, this works on my IE6, Netscape
7.1, Firefox 0.8:
.... when Javascript is enabled.

Quote:
function resizepics(w,h){
var p = document.getElementsByTagName('img');
for (var i=0; i<p.length; i++){
p[i].style.width=w;
p[i].style.height=h;
}
}

Mike



Reply With Quote
  #10  
Old   
JotM
 
Posts: n/a

Default Re: How to resize <IMG> width absolute and height relative ? - 05-05-2004 , 10:41 AM



Wladimir Borsov wrote:
Quote:
As well known for <IMG ...> tags in web pages a width and a height attribute can be
applied. What I want to do now is to fix the width for ALL the images on my web page
to exactly lets say 70 pixel regardless how big the originals are.
Resize the images with a editing app. Client-side resizing will not
exactly enhance the quality of the image. (to put it mildly) Especially
images with repeating structures are prone to moire effects if you do.

--

/************************************************** **************************
JotM aka Jaap van der Heide
Remove ".XXXnospamXXX" for a valid return address
Please reply to a news message in the group where the message was posted
************************************************** **************************/



Reply With Quote
Reply




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off



Powered by vBulletin Version 3.5.4
Copyright ©2000 - 2008, Jelsoft Enterprises Ltd.