Image size JPEG

Harry Schurink

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Feb 16, 2004, 6:31:30 AM2/16/04

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Hello,

Can anyone give me pointers on how i can determine the width and height of a
JPEG image?
Loading the image is not an option.
I have found a lot of scripts how to extract this info from a JPEG, but they
are all tediously slow.

There must be a faster way to find these "magic numbers" because when i put
the cursor over a jpg-filename in the explorer, the popup text immediately
tells me its 1600x1200
The fastest powerbuilder-script/exampes I have found take bout 5 seconds on
a 2ghz P4
(including the one i have written myself a couple of years ago).

Please
Anyone?

Grtz
harry

JHP

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Feb 16, 2004, 9:50:51 AM2/16/04

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Not sure if this will help:

I set an invisible picture object on my window and in a button clicked event
I coded the following:

Int li_width, li_height

p_1.PictureName = "C:\Graphics\cloud.jpg"
p_1.OriginalSize = True
li_width = UnitsToPixels(p_1.Width, XUnitsToPixels!)
li_height = UnitsToPixels(p_1.Width, YUnitsToPixels!)
MessageBox(String(li_width), li_height)

HTH

"Harry Schurink" <h_schurinkATtsdDOTnl> wrote in message
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Roy Kiesler [TeamSybase]

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Feb 16, 2004, 2:50:37 PM2/16/04

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Take a look at
http://www.teamsybase.com/roy.kiesler/downloads/imageutils.zip

Note: the demo still has a small issue with JPEG images that contain a
thumbnail as part of the header -- in that case, the size returned is that
of the thumbnail, not the full-size image. I haven't had the time to drill
this one down -- maybe you will...

--
<hopethishelps/>
Roy Kiesler [TeamSybase]
SDN CodeXchange -- http://codexchange.sybase.com

"Harry Schurink" <h_schurinkATtsdDOTnl> wrote in message
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Gerald F. Whitmarsh

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Feb 16, 2004, 3:25:12 PM2/16/04

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I used to have that problem. The locations of the dimensions seemed to
vary with the type of JPG-scanned, camera etc. I then purchased a
brilliant library - ImgSource from
http://www.smalleranimals.com/isource.htm.
Never looked back.

HTH
Gerry

On 16 Feb 2004 03:31:30 -0800, "Harry Schurink" <h_schurinkATtsdDOTnl>
wrote:

Harry Schurink

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Feb 17, 2004, 6:02:40 AM2/17/04

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Hi Roy,

I know your library, but that has the same performance issues as the sources
that i have,
(downloaded it yesterday before posting this message)

Investigation shows that you used the same original perl-source that i used.
So its slow too...

There must be a way to find those properties quicker...

Anyone?

"Roy Kiesler [TeamSybase]" <SPAM_FREE_...@teamsybase.com> schreef in
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Roy Kiesler [TeamSybase]

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Feb 17, 2004, 8:12:09 PM2/17/04

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C++? Tyler has a project on CodeXchange that's a wrapper for some
open-source imaging product -- perhaps that will do...

--
<hopethishelps/>
Roy Kiesler [TeamSybase]
SDN CodeXchange -- http://codexchange.sybase.com

"Harry Schurink" <h_schurinkATtsdDOTnl> wrote in message

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