How do I resize a picture when I save it so it takes up less disk space??

[mhayenga]

Ok, I'm making another database application which involves needing to access an image from a database. I have it setup so the usere can select any image and place it into the viewing field, but I'd like to make it so that the picture would only be saved as something like 240*320 pixels. This would not take up as much space on the disk. How would I do this apart from an activex control...(I'm downloading one currently which should do this resizing operation, but it'll probably take up too much space and offer too many imaging options that I'll never use, since it's not a paint program I'm making.)


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Mitchell Hayenga
[email protected]

[RogerH]

I think you can't avoid using a third party control unless you want to write an image compressing tool.

Roger

[andymac]

Hi,
This is possible as I've had to do similar (I've got a bitmap in memory and wanted to save it (see the http://www.vb-world.net/ubb/Forum1/HTML/015425.html thread). Bascially you have to do the following;

Assuming you have your picture in a picture box you can do it one of two ways

(a) - Rough and ready, StretchBlt your picture from it's current picture box into another picture box but scaled to be the size in pixels that you want. Then you can do a SavePicture thingy on the picture box
(b) - Scarey API.
Create a Memory DC (compatible with your picturebox)
Stretchblt your image into it to the scale that you want
Convert the MemoryDC into a DeviceIndependantBitmap
Save the Memory location for this DIB as a file

Either will work, but (a)'s far easier, but it depends on exactly how you want your application to work

cheers

Andy