If AutoFit is True and the image is updated (Update method) the Fit is called.

In this way you are not obliged to call fit each time you load a picture or each time the view is resized.

When AutoShrink is True IEViewer follows these rules:

- If an image is bigger than IEViewer window it is Shrink to fit;

- If an image is smaller than IEViewer window it is displayed 100%

When AutoStretch is True IEViewer follows these rules:

- If an image is bigger than IEViewer window it is displayed 100%;

- If an image is smaller than IEViewer window it is stretched to fit

If DelayDisplaySelection is True, the selection is displayed with delay.

This allow you to quickly navigate the image (zoom and scroll) and only after you have finished the navigation the selection is displayed.

IEvolution has a timer that decrements a counter at each tick (you can set the tick delay using DelayTimer property).

This timer controls the selection animation and the application of filters on scrolling (when DelayZoomFilter is True).

If you set negative values DelayTimer changes its behavior. Negative values represent the maximum CPU time that ImageEn can use to show selections. For example setting:

ieViewer1.DelayTimer = -10;

IEvolution will not use much more than 10% of the CPU time.

The default DelayTimer's value is -20 (maximum 20% of the CPU time).

If DelayZoomFilter is True, the filter is applied with delay.

This allow you to quickly navigate the image (zoom and scroll) and only after you have finished the navigation the filter (quality zoom) is applied.

Represents a IEDirectShow object.

It allows control of some DirectShow features, such as video capture, audio capture, multimedia files capture as well video rendering, and multimedia file writing.

DiscardSavedSelection removes the last saved selection from the stack (saved using SaveSelection).

You can use this method if you don't want restore the saved selection.

Specifies where to draw the grid if DisplayGridKind is PixelGrid.

-1 : current layer (default behavior)

>= 0 : specific layer

DisplayImageRect shows the specified image rectangle adjusting zoom and pan.

The rectangle will be adjusted to get right aspect ratio.

DShowEvent occurs when one o more events are ready.

You should call DShowParams.GetEventCode until it returns IEEventCode.NOTAVAILABLE (no more event available).

DShowNewFrame occurs when a new frame is ready to be read.

This event is active when you are using DShowParams and DShowParams.EnableSampleGrabber is True.

Here you can call DShowParams.GetSample() to get currently captured sample.

Enable/disable alpha channel

Some formats like Gif, Png, Tiff, Ico, Cur contains an alpha channel that specifies the image’s pixels transparency.

If ZoomFilter is not None IEViewer disables the alpha channel.

Set ForceALTkey to True to emulate ALT key pression.

It allows to make and modify selections or vectorial objects always maintaining apsect ratio.

Default is False.

Calculates the length (perimeter) of current selection.

If selection is made of two point, GetSelectionLen calculates the line length.

If selection is made of three or more points calculates the perimeter.

The LayerNotify event occurs whenever a layer is selected, moved or resized.

Only user actions can fire this event.

Options to control layer behavior.

Default enabled: AllowMultiSelect, AutoUndoChangesByUser, AutoPromptForImage, AutoFixBorders

Whether a cached view of every layer is stored in memory.

Supported values:

-1 : A cached view is stored for each layers. This provides the best performance, but can use a lot of memory if there are many layers

0 : No cached views of layers are stored. This uses the least memory

>0 : Specifies a maximum number of cached views to store

Default: 0

When enabled, any part of layers that are outside the background image (layer 0) area will not be displayed.

If true, it overrides the Cropped property of individual layers.

Default: False

If LayersDrawBox is true, a box is drawn around layers.

If Layers[].VisibleBox is false, no box is displayed (LayersDrawBox doesn't care).

If Layers[].VisibleBox is true and LayersDrawBox is false, a box is drawn only on the selected layer.

If Layers[].VisibleBox is true and LayersDrawBox is true, a box is drawn on all layers.

Displays the user's rotation with the selected anti-alias effect immediately (i.e. before calling LayersFixRotations).

Note: Preview of large rotated images at high quality can be slow, so it is recommended that you also use LayersFastDrawing.

Default: False

If true (default) selection constrains are active.

The unique layer selection constrain controlled is IELayer.Selectable.

Loads layers, selection and some other parameters like Zoom and Scroll position.

Look also SaveState method.

Loads layers, selection and some other parameters like Zoom and Scroll position.

Look also SaveState method.

MaxSelectionDistance indicates the maximum distance (in bitmap pixels) from which an object may be selected.

If you left click in a zone beyond this distance no object will be selected.

-1 (the default) disables maximum selection distance (a click always select an object).

Specify which mouse activities are performed when the user interacts with the IEViewer component with the mouse.

Note: Multiple interactions can be specified, but activities that are not mutually compatible will be excluded

MouseWheelXXXXX properties allow application to customize the mouse wheel behavior.

MouseWheelAction specifies the task to perform on mouse wheel events.

Specify MouseWheelActions.None for no operation, MouseWheelActions.VScroll for vertical image scroll or MouseWheelActions.Zoom for zoom-in/out (default MouseWheelActions.Zoom).

MouseWheelXXXXX properties allow application to customize the mouse wheel behavior.

If MouseWheelInvertDirection is True it inverts wheel direction (default False).

MouseWheelXXXXX properties allow application to customize the mouse wheel behavior.

Value or percentage of variation (default 8).

MouseWheelXXXXX properties allow application to customize the mouse wheel behavior.

MouseWheelVariation specifies how much scrolls or zoom in response to mouse wheel rotation.

If MouseWheelVariation is MouseWheelVariations.Absolute, MouseWheelValue will contains the absolute value to add or substract from current value.

If MouseWheelVariation is MouseWheelVariations.Percentage, MouseWheelValue will contains the percentage of variation from current value (default MouseWheelVariations.Percentage).

MouseWheelXXXXX properties allow application to customize the mouse wheel behavior.

If MouseWheelAction is Zoom, MouseWheelZoomPosition specifies where the zoom act.

The default is the center of the control (MouseWheelZoomPositions.Center), otherwise (MouseWheelZoomPositions.Mouse) zoom at the mouse position.

Represents the maximum pointer distance from the object (in pixels) that allows object moving.

Default is 1.

When true (default), moving objects or doing other visual operation disables antialiasing and shadows.

If you have a fast machine, disable this property to increase user graphical experience.

Returns the horizontal position where the image has been drawn. If ImageHorizAlignment is Left, OffsetX will be zero, whereas for iehCenter it will be (Control Width - Image Width) / 2.

Note: This value only indicates the initial draw position for an image, it is not related to scrolling (unlike ViewX).

Returns the vertical position where the image has been drawn. If ImageVertAlignment is Top, OffsetY will be zero, whereas for ievCenter it will be (Control Height - Image Height) / 2.

Note: This value only indicates the initial draw position for an image, it is not related to scrolling (unlike ViewY).

Resets some IEViewer properties to the defaults.

In details ResetState() removes selection, empties layers, sets input/output parameters to the defaults, resets Zoom and Scroll and removes Undos.

Leaves LegacyBitmap unchanged.

SaveSelection pushes the current selection in a stack.

You can use RestoreSelection to get back to the last saved selection.

Saves layers, selection and some other parameters like Zoom and Scroll position.

Look also LoadState method.

Saves layers, selection and some other parameters like Zoom and Scroll position.

Look also LoadState method.

Specifies the selection aspect ratio.

If SelectionAspectRatio is -1, the aspect ratio is active only when user press the ALT key, and it is automatically calculated.

If SelectionAspectRatio is 0, the size of the selection is fixed and determined by SelectionAbsWidth and SelectionAbsHeight properties.

If SelectionAspectRatio is >0, ImageEn maintains the specified aspect.

SetExternalImage makes it possible to connect a IEViewer component to another one, sharing the same bitmap, or to a IEImage object.

This is useful to view the same image with multiple IEViewer components, loading the image only one time.

Sets ViewX and ViewY in one step, using smooth scrolling.

To control smooth use SmoothScrollValue property.

Sets the image zoom (i.e. by setting IEViewer.Zoom), but does so with smooth zoom (image will slowly zoom to the new value).

If ZoomX and ZoomY are not -1 then the zoom will be centered at a specified position (specified in client coordinates). This is like calling IEViewer.ZoomAt.

Specifies the scrolling smooth when SetViewXYSmooth is called or when EnableMovingScroll is true.

Large values increase smooth. "0" disables smooth (acts like SetViewXY).

If SoftCrop is AlphaBlend then the SoftCropValue specifies the level of transparency from 0 (minimal) to 255 (fully)

If SoftCrop is Add then the SoftCropValue specifies the amount of color shift from 0 (minimal) to 255 (extreme)

This method sets ZoomX and ZoomY values to stretch the image inside component borders.

Using Stretch you loss the image aspect ratio and some functions, which require aspect ratio, may not properly work.

UpdateImage method updates the component with the actual image and redraw the client area.

You have to call Update method whenever the Bitmap field is modified.

Update is called automatically when an image processing or input operation is executed.

ViewX is the first column displayed on left-upper side of the component.

You can set ViewX to simulate horizontal scroll-bar movement.

ViewY is the first row displayed on left-upper side of the component.

You can set ViewY to simulate vertical scroll-bar movement.

ZoomFilter specifies the filter to apply in zoom-in (Zoom property) operations.

The fastest way to zoom a picture is to set ZoomFilter to None (default).

Zooms to a rectangular area specified with Select methods.

This function allows to specify aspect ratio.

This property is active when EnableZoomOnSelect is enabled.

If true (default) the selected rectangle is adjusted to maintain aspect ratio.

Otherwise (false) the image losses aspect ratio (ZoomX!=ZoomY and Zoom value is invalid) making it stretched inside the component.

ZoomX specifies the horizontal Zoom.

Using this property (and/or ZoomY) you loss the image aspect ratio and some functions, which require aspect ratio, may not properly work.

Setting ZoomX and ZoomY to the same value is equivalent to set Zoom.

ZoomY specifies the vertical Zoom.

Using this property (and/or ZoomX) you loss the image aspect ratio and some functions, which require aspect ratio, may not properly work.

Setting ZoomX and ZoomY to the same value is equivalent to set Zoom.