PanoTools NG:
Re: Re: Which viewer to use...
Fulvio Senore 2006-Sep-05 16:17:39
scannerist ha scritto:
> --- In #removed#, Fulvio Senore <mailing@...> wrote:
>
>> scannerist ha scritto:
>>
>>> --- In #removed#, Fulvio Senore <mailing@> wrote:
>>>
>> It think that a good solution is to use java to show a relatively small
>> version of the pano as a first step. Then you could use QTVR to show
>> fullscreens for those who have it installed. You could also try to
>> detect the installed viewer and act accordingly, but this would require
>> dynamic page generation.
>>
>
> Do you have a range of image sizes and compression rates you're
> comfortable with for the small version and for the large version?
>
>
Compression rates do not change the memory requirements, they only
affect the download time.
About image sizes, I cannot help you. I usually take landscape panos
from mountain tops where there is not much interest in looking at your
feet, so I create images with a limited vertical field of view. As a
result memory is not an issue even with large images, since the
equirectangular image has a very limited height leading to a limited
memory requirements.
Using 360x180 degrees panos requires a lot more memory.
>> Since all users have the same amount of memory it is probably better to
>> create images small enough than to create larger images and have the
>> clients to downsize them after a longer download.
>>
>
> Given those preferences, what viewer and image sizes are you talking
> about?
>
The question is not very clear to me. If you want to compute the image
size needed to show a pano in a window of a given size you can use a
simple formula:
panoWidth = (viewerWidth*360)/hFov
where hFov is the horizontal field of view of the viewer, in degrees.
The formula gives you the size needed to view the pano at a zoom level
of 100% in the viewer.
I have found that it is better to use a slightly larger pano image for
best results, say 10-20% more.
Of course the formula holds for every viewer.
Fulvio Senore
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