Multi-frame Images

Animated or multi-frame images can be created from a large panel containing subimages, or from separate individual images. To create an animated image from separate images, start with a series of single-frame images of identical size and color depth. Better results are obtained if the frames are 24 bits/pixel, then converted to 8 bits/pixel afterwards if necessary. When imal changes the depth of an image, all the frames are converted simultaneously and a common colormap is generated that fits all the frames.

Creating multi-frame images from a panel

Panelmultiframe image takes an image consisting of several sub-images, and puts each subimage into a multi-frame image. If 'Manually find frames' is checked, you must click on the upper left corner of each subimage to indicate its location. Otherwise, the subimages are found automatically, using the specified x and y spacing between subimages and the specified upper left x and y for the first subimage to calculate the location of each subimage.

The program takes a wild guess as to the size of the multiframe image and the number of frames to create from the panel. These values should be corrected as needed.

Example: Part of a typical composite image suitable for building a multiframe image.

Several frames from an image of a rotating F1-ATPase $\alpha_3\beta_3\gamma$ subcomplex. Noji et al. [1] coupled the $\gamma$ subunit of F1-ATPase to a fluorescent actin filament and observed that this protein acts as a naturally-occurring molecular motor. Only 5 of the 105 frames from their article are shown.

If a frame is not aligned correctly with the other frames, use the ``Image..shift'' menu to adjust its position (see ``shift'', Sec. 8.7). If this doesn't work, use the frame controls to move to the offending frame and copy the desired region manually onto the image. The region will be pasted onto the frame that is visible.

Combine imagesmultiframe works similarly, except that instead of a panel, the subimages are taken from a list of individual images. When you click `Accept', an information box appears allowing you to enter the image numbers to use for each frame. A multi-frame image will then be created with each specified image comprising one frame.

Note: The images to be combined must all be the same pixel depth. If the source images are already multi-frame images, only the first frame is used.

Example: Creating animated GIFs

NOTE: Animated GIFs must be 8 bits/pixel.

1. Convert each source image frame to 24 bits/pixel.
2. Add the desired content to each frame.
3. Click ``New/Resize image...Images multiframe'' option to create the animated multiframe image.
4. Enter the list of image numbers for each frame in the information box that appears. This is a series of numbers or a range, e.g., `1 4 9-12 22' would include images 1,4,9,10,11,12, and 22 as frames in the new image.
5. Set the frame rate using the ``Image properties'' dialog.
6. The new multiframe image will have the same depth as the source frames (i.e., 24 bits/pixel). To save as a GIF, it must be converted to 8 bits (``Color...Change Image Depth'').
7. Save final image in GIF89 format (GIF87 images cannot contain animation).

Converting a multiframe image to a panel

Multiframepanel converts a multi-frame or animated image to a large single image in which each frame is lined up in columns. Set the desired screen position for the new panel image, the desired number of columns, the upper left position in the panel to put the first frame, and the x and y spacing (in pixels) between frames. A new single-frame image of the appropriate size will be created, in which each frame of the original is visible.

Split multiframe images is similar, except instead of creating a panel, it creates a number of small single-frame images from the multiframe image, and then lines up these images into columns (see below).

Displaying multi-frame MRI images as an image panel

MRI and PET scan images are often more conveniently viewed as a series of individual frames than as animated images. This can be done by selecting ``New/Resize image...Multiframe Images'' option. Click on the ``Align Images'' toggle button and select the desired number of columns. Set the desired x and y position for the upper left of the new display and click ``Accept''.

This will convert the multi-frame image to separate images, one per frame, aligned in sequence from left to right and top to bottom. The frames can be manipulated or saved individually. The original multiframe image is still intact in its original location.

WARNING Each image created with this option contains only a single frame. If you wish to save all the frames to disk, be sure to save the original multiframe image, or alternatively click ``Images multiframe'' to rebuild the multiframe image. (This should be easy because the correct parameters are automatically set when the image is decomposed into separate frames).

If the `Align Images' toggle button is ``off'', the new images will be stacked on top of each other instead of lined up in columns.

Multiframe images can be split into an image panel automatically when reading from disk by clicking the ``Split frames'' toggle button.

Adding a frame

Add frame to image increases the number of frames in the current image by 1. The new frame contains all zeros, i.e., is black.