Sunday, March 23, 2003

This is an edited version of a panoramic picture I took of Calgary today.

The original measures 2839 X 772 pixels and tips the scales at right around 1 MB. The picture below has the same "physical" dimensions, but I've constrained its size to 284 X 77 in the HTML of this page.

I used the "Save as" function of Microsoft Photo Editor to make a "smaller" Joint Photographic Experts (JPEG, also JPG) version of the file (~175 KB). It has the same physical dimensions, but its "size on disk" is about 1/10th of the original. Of course there is a corresponding drop in the "quality" (i.e., resolution) of the graphic, but this is a trade-off I'm willing to make to ensure greater accessibility for dialup visitors.

As it is, time for download of the "full-size" version of the page is much longer than I'd like (30 - 40 seconds at 34.6 kps). The goal here was to strike a balance between making a large file available and still accessible to all users. In this example, dialup users can at least see something happening (the beginnings of the graphic being "painted" on their display) -- about 1/2 of the graphic after 15 - 20 seconds @ 34.6 kps -- and may be more inclined to "play along."

If it takes too long for visitors to see your content, they'll be scrambling for the stop button on their browsers and heading elsewhere.

A panorama of Calgary in early spring

Click the picture above to see the "full-size" version of the 175 KB graphic.

I'm experimenting with file sizes and screen resolution quality as both relate to graphics and video on the web as my term project for CTL 1799.

I've been playing with MS Photo Editor and Media Encoder to produce JPG and WMV files. I'm also using use Adobe Premier to combine file formats (i.e., AVI, WAV and MOV (QuickTime)) and export to AVI format. These are then "encoded" to Windows Media Video (WMV) for streaming.

Videos require Windows Media Player for playback -- free viewers are available for Windows and Macintosh operating systems. Keeping file sizes small and therefore "more accessible" will be a prime objective at each step in the process.

I'm using the Olympus C720 for stills and videos. I've been using the C720 for about 6 months and am very impressed. I used the Camedia software which ships with the camera to "stitch" the pic above.

As always, watch this space for updates.

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