Create faster preview for pictures?

[omit59]

I'm using loadimage() and then resizeimage() to make a directory preview for pictures, but if there are many pictures in the directory it takes quite along time to do that.

Is there any other way to do this (mayby API) faster???

Timo

[El_Choni]

Jumped on this somewhere (works in XP only, AFAIK):

You can extract thumbnails by calling IShellFolder::GetUIObjectOf to obtain an IExtractImage interface for each item you're interested in. But unfortunately you don't get a free ride on the shell's thumbnail cache.

Apparently, that's what all these thumbs.db files are about...

[omit59]

OK, I will use LoadImage() and just wait a little longer...

Thanks El_Choni

Timo

[Trond]

Make sure you've set the resize mode to raw and not interpolated with the ResizeImage command. It's an optional parameter that's set to interpolated by default. That is nicer but much slower.

[omit59]

That was really good point, I didn't even think that interpolated parameter was used by default. Time save is about 20%, and preview is good enough!

Thanks a lot Trond

Timo

[Pantcho!!]

Yeah! thanks alot this is damn faster!!

[Hurga]

Just a thought, not sure if its really faster...

Here a piece of pseudo code

Code: Select all

Load the file of the image in memory (not as an image)
get the pointer of the first pixel.
original size i.e. 100x300
create image 10x30
if in the example the size reduction in 10, so add 10 to the pointer and get the next pixel there.
Write the pixels in a new created image.

Maybe its a bit faster then load image, resize image and so on.

[Yogi Yang]

I think for all kinds of very fast and accurate image manuplations you should use ImageMagick which is OpenSource and really very very powerfull.

http://www.imagemagick.org

I use its varient GraphicsMagick - graphicsmagick.org which is a COM version of ImageMagick in VB whenever I have to deal with images. Use this only if you do not want to convert the image data to PB's internal image format.

Hope this helps