Open a file from the "Open…" item inthe "File" menu.
• Inspecting and Resizing the Images
The images can be made larger for inspection. They can be adjusted to any size bny clicking and dragging in the lower right corner. A full screen image can be made by clicking the zoon box in the title bar.
• Calibrating the fisheye image
- Setting the fisheye circle
- Manual adjustment
Select "Adjust fisheye Circle" from the "Warp" menu. When done adjusting it, deselect it, to avoid accidental changes. Undo is available for manual adjustment of the fisheye circle.
- Moving the circle
Click and drag in the interior of the circle. The arrow keys may be used to move by one pixel at a time. In combination with the shift key, larger steps are taken.
- Resizing the circle
- Changing the radius from the center
Click on the circle and drag. The center remains fixed.
- Changing the diameter, keeping one side fixed
Option-click on the circle and drag. The opposite side of the circle remains fixed.
- Dialog adjustment
- circle size
This is specified as a percentage of the smaller dimension of the image.
- circle location
This is specified in pixels.
- field of view
This is the field of view represented by the circle.
- rotation by ±90° and 180°
Select one of the radio buttons. The source image itself is not rotated, but rotation is performed upon projection.
- correcting for radial distortion
The coefficients for a cubic polynomial in the azimuth angle may be specified. There is no intuitive way of setting these (yet).
• Setting Perspective Parameters
- Choosing the dependent parameters
This uses a nonstandard interface for radio buttions. The highlighted radio buttons indicate independent parameters. Only two of the three sets of parameters are independent, and you can choose which they are. By clicking on the radio button for an independent parameter, you can change it to a dependent one. The highlights always indicate the variables which can be changed. It may be confusing when you click on an unselected boutton, when it doesn't respond. You instead need to click on a selected button to deselect it. By default, the width and height are dependent; these are varied as you change the FOV or zoom. By clicking on the Zoom radio button, you can then adjust the height and width, and the zoom will be adjusted accordingly.
- Setting the field of view
The left box is the horizontal field of view, in degrees. The right is the vertical field of view. If the "square" checkbox is checked, then cthe changes to one wil be copied to the other. A value of 115° will produce as many pixels as in a 180° fisheye image. A value of 120°-140° is good. Larger than this will use an extraordinary number of pixels at the edges. However, I've made 165° and even 170° images, with enough memory. Note that only multifinder memory is used, so it is counterproductive to set the memory partition to anything larger than 2 Mb; even 1 Mb will work for many jobs.
- Setting the image size
If you desire a particular size of image, these fields are for you. Make sure to Unselect another parameter (FOV or zoom) as the independent variable. Otherwise, any changes are ignored.
- Setting the resolution
The dimensions of the resultant image, in pixels, is specified here.
- Maintaining a square image
By uncheckingthis box, you can have independent control of the horizontal and vertical field of view or image dimensions.
- Generate hemicube (dangling faces)
The fisheye can be projected to a hemicube, by checking this box. The central face, plus four additional dangling faces are produced. If a field of view of other than 90° is specified, then the result will be shaped like a half of a cracker box or a cookie box instead of a cube.
• Setting Cylindrical parameters
- Setting the horizontal field of view
With a round 180° fisheye image, you can make this the horizontal field of view as large as 180°.
- Setting the vertical field of view
The vertical field of view has the same caveats as for perspective. Angles of 120°-140° make good use of the pixels. Larger values can be used, but are wasteful of pixels.
• Generating a Perspective Image
Select "Create Perspective". It may take a while. Zoom in and inspect it if you want.
• Generating a Cylindrical Image
Select "Create Cylinder". It may take a while. Zoom in and inspect it if you want.
• Batch Processing
- Starting the batch
Drag several images from the Finder onto the DeFish icon. You will be prompted, through a series of dialogs, to set the parameters. When the last one is OK'ed, all the images will be batch processed.
- Setting parameters
A series of dialogs are brought up to set the parameters for the batch.
- Selecting type of projection
Select either perspective or cylindrical.
- Setting output file name scheme
You choose the suffix to be appended to the input file name. You can choose to strip the suffix from the input file name.
- Setting fisheye parameters
This is the same dialog as described above.
- Setting perspective or cylindrical parameters
These are the same dialogs as described above.
- Fine tuning parameters
The batch process normally only accommodates parameter specification through dialogs. However, the interactive fisheye circle adjustment may be used as follows:
(1) Open up (by dropping or through the "open…" menu item) a typical file.
(2) Select the "Adjust Fisdheye Circle…" menu item abnd interactively adjust the circle. Deselect this item.
(3) Without closing the application, drop the batch of files onto the opened DeFish icon.
• Saving Images
When satisfied with the results, chose "Save…" from the file menu.
• Saving and restoring Preferences
A list of commonly used settings can be saved as preferences. They are listed under the "Choose settings" menu on the Warp menu. Select "Save Settings…" under the File menu to save them. The file is TEXT, and hence may be edited outside of DeFish. Spaces are added for readability, but are not necessary. Useful settings may be shared among users.
• Examples
◊ Use 100% and 180° for an 8 mm lens on a 35 mm camera.
◊ Use 180% and 170° for a 16 mm lens on a 35 mm camera. The maximum fields of view are about 93° x 140°. Use the "dangling faces" (hemicube) to quickly find the limits of a new lens.
• Bugs
- none known.
• Feedback
Report bugs, crashes, problems, requests, enhancements, praises, etc. to turk@worldserver.com.
Do you have some parameter settings that work well for you? Send them to me, and I'll include them in this file.
This application is freeware and runs only on the Power Macintosh. If you feel you must give some money away, please join the International QuickTime VR Association (IQTVRA), and make an extra donation there to encourage immersive media authoring tools, tutorials, and promotions of an open, supportive spirit in our field.
