Does anyone have any idea of compressing .jpg files in VB6 on WinXP
Thanks
Dave

What do you mean by compression? Changing JPEG quality? Or compress the
file, like ZIP? Or other?

JPEG have quality levels to reduce their size. If you only need this for one
specific task, you can use IrfanView freeware, which can do batch
conversion/rename, via the user interface, or by command lines.

There's pure VB code here:

http://www.Planet-Source-Code.com/vb/scripts/ShowCode.asp?txtCodeId=50065&ln
gWId=1

  Two problems, though: When I tried it the code
seemed to be quite slow. Also, the author has
included an absurd, "blowhard" license that
claims you have no right to use the code for anything
commercial without permission, and that all uses
require a vanity acknowledgement of the author.

  There are also a number of compiled options. There's
ImageMagick, open source, but from what I've
seen it seems to be wildly bloated, and it no longer
supports Win9x. It's probably only relevant if you
wanted to recompile only the JPG code (C++). There's
also an Intel DLL somewhere,
but that had slight license restrictions and I think they
discontinued it.

   Several years ago I went looking and
tried a half dozen or so options. I ended up with
something called nviewlib.dll. It works well and is one
of the smallest DLLs I found. The DLL has a Borland
icon, so it may just be a wrapper for Delphi JPG
handling. I don't know. But I've had good luck with it.
(The license is "postcardware" but the email address
seems to be long-since inactive.)

  There's also what seems to be a similar thing from
Jerry French, who used to frequent this group:
http://www.jerryfrench.co.uk/pictojpg.htm
  It comes with Delphi source code, and Jerry always
had very dependable info. in his posts here, so I'd be
inclined to trust whatever he wrote.


Show quoteHide quote

kiwi wrote:
Take a look at what the Intel Jpeg Library offers (IJLxxx.dll)

Here's a VB example:

http://www.vbaccelerator.com/home/VB/Code/vbMedia/Saving_Pictures_to_JPG/Using_Intel_JPG_Library/article.asp

kiwi wrote:
One more option for the mix...

   The FreeImage Project
   http://freeimage.sourceforge.net/

Vista and later include WIA 2.0 which can handle this sort of thing.  The
COM interface is fairly robust and simple to use from VB6 or VBScript.

You can download it from Microsoft and install into XP SP1 or later, and it
can be redistributed.  From the readme:

"The Windows Image Acquisition Library v2.0 is only designed to support the
PNG, BMP, JPG, GIF and TIFF image formats.  It should not be relied upon to
support other formats, though they may appear to be supported depending on
system configuration."

Download multiple files concurrently using WinHttpRequest
When the compiler freezes.... what is the rescue?
How to Change $(AppPath) in PDWizard?
Karl, I need to understand your Timer!
Run-Time Error 5 - 'Invalid procedure call or argument' error msg
Overcoming a MsgBox's shyness
File not found
How to obtain the new GUIID key on a new build of an ActiveX DLL or an ActiveX OCX
Autosize DataGrid Columns
Using Outlook object