You've seen those cool QuickTime VR movies on the Web
and you want to learn how it's done? Well, you've come to the right place. Internet
Brothers to the rescue again. I'll be talking about creating panoramic movies here,
the kind you can move from side to side up to 360° as if you're standing on the
spot where the panorama was captured, spinning around. In the first part of this
article I discussed panoramas from the camera side. That's just half the job; putting
it together on the computer can be just as much fun. Now that you've captured your 18 images or so, you're
ready to head for the computer. First, you'll need some software for stitching the
images together and creating the QuickTime movie file. There are several programs
available for generating QTVR panoramas. These include
VideoBrush Panorama;
PictureWorks Spin Panorama;
and the one I use,
Apple
Computer's QuickTime VR Authoring Studio. No matter how you get the images into your computer,
whether by scanning prints, having your film processed to PictureCD, or using a digital
camera, reduce your images to a manageable size. I've found that images larger than
1000 x 750 pixels at 72 dpi take an awfully long time for the software to stitch. So,
the first thing I do is reduce the file size of each image
with Adobe Photoshop. There are lots of other
programs that can adjust image size such as Thorsten Lemke's shareware,
GraphicConverter.
If you've been manipulating photos on your computer for long, you probably already
have software to handle the task. The stitching process will be a little different
with each program. With Apple's QTVR Authoring Studio, the first step is to add the
images and be sure they are placed in the preview window in the proper order. In this
preview window, it's pretty easy to see if there is an image or two that is significantly
lighter or darker than the rest. If that's the case, it may be necessary to adjust the
image with your photo editing software. This can be the most time consuming part of the
whole process if you've used an auto-exposure camera, as
discussed previously. I sometimes spend hours tweaking the brightness of all
the images until I'm satisfied with the way the photos blend together. QTVR Authoring Studio does give you the option of
doing everything at once. It may take an hour or more. You can walk away for a while,
come back, and probably be totally unhappy with the results of the finished panorama.
Instead, I take it one step at a time. Do the stitching first. Don't bother to tile or
convert the stitched image to movie format until you preview it with an image viewer
to look for flaws. Often, when previewing the wide stitched image, several points where
the stitching wasn't accurate become apparent. Use the opportunity to go back and
manually adjust the stitching, then preview again. An interesting quirk (feature) in the QTVR Authoring
Studio software — when creating a panorama movie from an already stitched image,
the width of the image in pixels has to be evenly divisible by 96 and the height must
be evenly divisible by four. (This may be a problem if you have resized the stitched
image.) So, the last step before creating your movie is to make sure this is the case. Use your photo editor to check the image size. Adjust
the height and width to accommodate this constraint. When the width is divisible by 96,
a pixel or two adjustment in height to make it divisible by 4 will not be noticeable.
Once you have your super-wide image finished to your satisfaction — there are no
visible seams and no incorrectly overlapped images — you're ready to create the
panorama movie file. Now you need to decide where and how the panorama
movie will be viewed. If you're putting it on your web site, you're not likely to want
to place a very large file, as your guests won't wait for it to load. If you're going
to view it on your own computer and have a fast CPU and a big hard disk, heck, make it
as large as possible! For the web you will probably want to reduce the size of the
stitched image to no wider than a couple thousand pixels (keeping in mind the 96 and
four rule mentioned above). An important point to remember — the finished
panorama window size has no effect on file size. It is the size of the original stitched
image that affects the ultimate file size. Make the original image almost as small in
height as you plan for the panorama window to be (unless you want the viewer to be able
to zoom in without loss of quality). Set the panorama software to compress the image
as much as you can (before image quality suffers too much) while it creates the
panorama movie. This should result in a finished movie that's around 200-300K in size. Experiment with this — more compression, poorer
looking image; less compression, better image but slower downloading on the web. Create
several movie files until you get a suitable file size and suitable image quality.
The photography and image stitching are the hard parts. Creating the actual movie file
takes only a few minutes, so you can do it over and over. With QuickTime Pro Player version 4, you can save
(export) your finished movie in streaming format before you put it on your website.
This means your viewers will be able to see the panorama (if they have version 4 of
the plug-in) at low resolution while it is still loading. This helps to keep them
around until loading has finished. When you're done with all this (whew), you have a
wonderfully interactive panorama. Your viewers can feel like they're actually standing
in the spot you were when you started this whole process. They'll enjoy it. Pat
yourself on the back, nice job. To view actual QTVR movies built using the techniques
in this tutorial, go to
my personal site and have a look. Note: the free © Apple QuickTime
browser plug-in is required. Details are provided at the site. If these tips have been
useful to you, or you need some further advice, please
Digital Panoramas
17th of June 2000The Computer Side
A Stitch in Time
Software Is Written by Hardheads
Ready for Prime Time
net.weblogs.com
...an experiment in freeform discourse
OK, here's the deal.
Where are all the socks?
I personally lose about
one sock each month doing laundry. Conservatively, let's say that's 10 socks a year
and that there are 2 billion males on the planet who launder and lose socks at that
rate. Say socks typically last 10 years before disintegrating.
So we have 10 socks a year times 10 years times 2 billion equals 200 billion socks.
Assuming 20 socks a pound (I weighed them), that's 10 billion pounds of socks. Now,
just where are those 5 million tons of unmatched socks?
Huh?