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Multipoint Builder with Photographic Images(Thanks to Walter Johnson walter.johnson@utw.com for writing this document) |
Main Page Multipoint Page Photographic Tutorial Files |
How to link QuickTimeVR movies using MultipointThe primary steps are:
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You will need an accurate map, so draw one as part of step 1. MultiPoint supports 6 sizes for the input PICTs: the 3 original QuicktimeVR sizes (768x2496, 384x1248, and 196x624), and 3 more (2496x768, 1248x384, and 624x196) so you don't have to rotate. Decide ahead of time which size you are targeting to minimize resizing. Remember that only the height (the smaller number) is important. You must match it exactly. Your width will depend on your camera setup, so don't worry if it isn't close.
Put your nodes wherever you want, but remember where you put them. In order to link your nodes you will need to know 2 things about each node. You have to know the position of the node, i.e. where your tripod was sitting. You will also need to be able to identify the look at point. The look at point is any point in the direction your camera is pointing when you have shot exactly half of the panorama. It is also the center of your completed PICT, or 180 degrees from the seam in your PICT. MultiPoint takes these values as 2 x, y, z points. If all of your nodes are on the save level, you can leave y as zero and only worry about x and z.
You can capture the pictures in a variety of ways. How ever you choose to do it, you need to produce a PICT that is 768, 384, or 196 pixels in it's short dimension and usually longer than that in it's long dimension. I do this by mounting my camera vertically on a tripod using a bracket that allows the camera to pivot over the lens. Then for each node I shoot a series of pictures that overlap by about 50% and cover all 360 degrees. From there I usually have the film scanned to PhotoCD.
There are essentially two ways to combine the series of pictures into one long one. Apple's QTVR Authoring Suite comes with a Stitcher program that automates this process, or you can do it by hand. I don't own Apple's Authoring suite so I'll be talking about stitching by hand.
Open the pictures in your favorite graphics program and proceed to assemble them. I do this by creating a new document that is larger than I think I'll need and successively pasting each image in. I paste the image in and trim off some part of the overlap and then align it with the rest. This is the time consuming part since you want to hide the edges and color differences as much as possible. When this is done you should have a PICT that is the right height and not the right width. Resize only the length of the PICT to match the size you chose. Don't worry if your PICT now looks odd, you can adjust the Field Of View later to make it look perfect.
At this point you would normally have to rotate your image CCW 90 degrees. QTVR requires that the input PICTs turned such that the left edge becomes the bottom and the bottom becomes the right edge. MultiPoint will take the PICTs in either orientation however so a rotation is not needed.
You should have one PICT for each node, and all have to be the same size. Launch MultiPoint and select each of your PICTs and hit Add. Once you have them all, hit Done. If any of your PICTs are not one of the 4 QuickTimeVR sizes you will see an error. Next MultiPoint will tell you that camera information was missing for your files, just hit O.K. Now you should see a window with a red dot representing each of your nodes.
If you have existing QTVR nodes that you want to link, they can be included in place of PICT files. Make sure that the source PICT for each node is the same size.
Now you need to enter the camera position information for each node. Refer to your map and enter a position and look at point for each node. This is also where you enter the Field of View. If you are unsure what to put here, leave it as it is and adjust it later if your resulting node looks horizontally stretched or compressed. As you complete each one you will be able to see it move to it's position relative to the others. The dot in the middle of the colored circle is the camera position and the line extending out is the look at point. The length of this line is not important, just the direction it is going.
Once you have entered the numbers for each node, the hotspots will be shown as connecting lines. If you select a node you will also see 'flower petals' representing each hot spot. This version does not allow you to alter or remove hotspots. Compare the window to your map and verify that everything looks right.
Choose Save QTVR Movie. If possible, leave MultiPoint running while you try out your movie. This version of MultiPoint does not allow saving your project file and you may need to tweak your numbers a few times to get all the hotspots in just the right place. You may also want to adjust the Field of View on your nodes if they look distorted. The node that will open first can also be selected.
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