Effects are actions that are applied directly to slide images. gdvdslides supports three kinds of effects: crop, kenburns and scroll. These effects are created with controls shown directly below the image preview area. You can apply only one effect to each image in your slideshow.
Each effect has a Clear button and an Apply button. The Apply button will apply the effect to the selected image. The Clear button will clear all the controls for the effect and will remove any applied effect from the selected image.
The crop and kenburns effects each have coordinates involved with them. These coordinates can be entered by hand, but you will get a better result if you use the mouse and draw a rectangle around the area concerned. The rectangle will be drawn in the ratio selected for the video; either 4:3 or 16:9. Any other ratio of coordinates will cause the slide to have background showing around it.
Clicking and holding the left mouse button, then moving the mouse will cause a rectangle to be drawn on the image that will be the coordinates for the crop effect, or the starting coordinates for the kenburns effect. Clicking and holding the right mouse button, then moving the mouse will cause a rectangle to be drawn on the image that will be the ending coordinates for the kenburns effect.
The crop effect allows you to cut out the unimportant parts of an image. Only the part within the defined rectangle will be displayed in the slideshow video. You can draw the rectangle with your mouse on the preview image by holding the left mouse button down, dragging and then releasing the mouse button. An example of this is shown below.
Cropping a small area from a large image works best with images of high resolution. The image will be fuzzy if you try to crop too much from a low resolution picture.
You can draw the rectangle as many times as you want, in order to get it in the proper place. When you have a properly sized rectangle defined, click on the Apply button to apply the values to the selected image.
Alternatively, you can define the rectangle by hand, using any of the controls provided. We prefer the mouse-drawing method, as it is completely reliable and always results in a properly-sized image.
Ken Burns Effect
The Ken Burns effect is a combination of zooming and panning applied to a static image. It is named after Ken Burns, a director who makes extensive use of the effect in his award-winning films about diverse subjects like the Civil War, American parks and baseball.
The idea behind this effect is to define a rectangle where the viewing starts and one where the viewing ends. When rendered, the static image will begin by displaying the contents of the starting rectangle and zoom in or out and pan to display the contents of the ending rectangle. It is important to note that you should provide sufficient slide duration to allow this to be done smoothly.
To draw a starting rectangle, press and hold the left mouse button, draw the rectangle and release the button. To draw the ending rectangle, press and hold the right mouse button, draw the rectangle and release the button. You can do each of these as many times as you wish to get the rectangles drawn in the correct places. When you have them defined, click on the Apply button to apply the values to the image. An example is shown below.
This example starts by displaying most of the image, then zooms in while panning right to display the teardrop trailer.
Alternatively, you can define each of the rectangles by hand, using any of the controls provided. We prefer the mouse-drawing method, as it is completely reliable and always results in a properly-sized image.
The scroll effect is most useful for displaying panorama-style pictures that are not close to the 4:3 or 16:9 ratio of a video slideshow. The effect will start at one edge of the image and will scroll to the other edge. For example, "scroll:right" will start at the left edge of the image and will scroll until the right edge is displayed.