Filter dialogs in .net

Hello

I was wondering if the filters in .net have an option preview dialog like they have in the  C++ class library version of LeadTools?

Thanks

I'm afraid I did not fully understand what you mean. Which preview dialog are you referring to exactly?
Please send me a screenshot image that shows the preview dialog in our C++ class library.

Thanks,
Maen Badwan
LEADTOOLS Technical Support

Maen

I have included a screenshot of the dialog.  In the code I use the following to create the dialog;

LDialogImageEffect DlgImageEffect;
LDialogImageEffect::Initialize(0);
DlgImageEffect.SetBitmap(&m_LAnnoWnd);

SHARPENDLGPARAMS DlgParams;

There are other filters that have this feature like median, unsharp mask.

Thanks

LEADTOOLS .Net interface doesn't contain many common dialogs. It contains the RasterWindowLevelDialog and File loading and saving dialogs (RasterOpenDialog and RasterSaveDialog).

The main raster demo (Examples\DotNet\[CS or VB]\MainDemo) has some dialogs for many of the image processing functions so you may find what you need in that demo.

Thanks,
Maen Badwan
LEADTOOLS Technical Support

Thanks Maen.  I will check it out.

Maen,

I had a question about how the RasterWindowLevelDialog works.
Does the dialog maintain a separate copy of the image for itself to apply the effects?

I looked at the main demo and it does provide an interface for the values of a filter that can be modified,
but what I want to include is a preview of how those settings for a particular filter will effect the image.

From what I understand, I would need 2 copies of the original image.  One a baseline copy so that if a filter is already been
applied, I can apply the new filter settings to the original data and not have the effect of stacking filters every time a user changes a value.
The 2nd copy being the actual image to preview the effects.

Any thoughts on this approach?

Thanks

You actually need only one new copy for the "After" image in the preview. The "Before" image can be a reference of the original image you're going to process, since the dialog will not be modifying this image.
This means it will be painted in the dialog, but it should NOT be freed when you exit the dialog because it will be the same image from the form that originally showed the dialog.

So would I need to do a dispose on the "after" Image and then .Clone() on the "before" Image each time the user changes a setting for the filter?

My only concern is that some of my images may be large, and doing a bunch of deallocation/reallocations may cause performance issues.

Thanks

Yes, you have to dispose the image and re-run the effect on a new copy every time the user changes the setting.
And yes, this could be slow if the image is very large or the function is complex and performs a lot of processing.
For this reason, some of our C DLL image processing dialogs do not apply the effect directly when the user changes the slider. Instead, they contain a button labeled "Apply" that the user must click to see the preview change such as the attached screenshot.

What you can do to enhance performance, is either clone a portion of the image and display it in the "After" image then apply the effect to it, or resize both images to a small size in the preview window, but in this case, you must clone both, not only the "After" because you don't want to resize the original "Before" image.

Thank you Daoud, your reply has given me some things to consider.