I have been going through all the messages in this forum but could not find the answer:
Is there a formula to calculate the optimal tile size for a partial panorama?
When I have a window height of 600px and normal Fov why is a tile size of 600px not enough? (A higher tile size results in interpolation isn't it?)
I see that some people just say "200 pixels more than the window height" or "A little larger" but there must be a formula for that to get the best result? Too many extra pixels don't make any sense (and result in anti-aliasing??) and when i just use 600 px the image is not sharp at all but actually I don't understand that because making a 600px tile from a 600px image sounds right. I hope someone can help me with this. Thank you in advance!
I do not think you will find an exact formula because each panorama image contains more or less detail. More detail larger file size.
However, I find that I always start MAX image size [bigger is always better]... to maintain image quality sharpness and detail. It is true, you can always down size... but the reverse is not true.
What we do is first make a full 360 image. Then we limit the left and right viewing angle to the needed image area for partial panoramas.
Our full 360 image is the original RAW converted to 16bit TIF and stitch 5000 x 2500 140mb image [ 4 images at 90 degrees].
Then we use a combination of cube face sizes to determine the image quality and cube face Compression to determine the overall QTVR .mov or flash .swf file size around 1.5 to 2mb. To start sometimes we use 1900 as cube face sizes and we use 40% for the zenith and 30% nadir cube face. We use 80% for the remaining cube face compressions.
Our target file size for web delivery is 1.5 - 2.0mb QTVR mov or Flash .swf. Currently we display or panoramas at 1024 x 600 which is suitable for commercial full screen display on a 24" computer monitor.
Thanks, but that's not exactly what I mean. I have an image with a height of 600 px and in my final qtvr I also see 600 px height so why is a 600 px height tile size not enough? Is trial and error the only way to find the best value?
Actually I see no panoramas with that resolution on your website. Most of them are scaled to fit the window size (99%, 91%) so you don't really use 1 size for your panorama's.
What I want is a fixed size without scaling and no possibility to zoom in or out , then there must be optimal quality settings and is a real sharp image possible I think.
Your original image as it came from the camera must have been larger than 600 high.
Feel free to stitch to original camera image height which should be well over 2000 pixels high. Hmm guess I better ask first what camera are you using to capture the original images??
Yes you are correct... you will not see any images on our site with a small 600 high images. The viewer might display 600 high... but the images are well over 2000 pixels high.
Concept is... if your viewer dimensions are 600h x 800w... then your images can be 3x the viewer size in height. So images should be 600 x 3 = minimum 1800 high.
An image with 1800 pixels high being displayed in a 600 high viewer will [or should be] very detailed and sharp. However, if you have a 600 high image disaplayed in a 1800 high viewer.. the image will be stretched to fit the viewer size... and will appear to be highly pixelated [read blurry].
As mentioned before. You will not find a mathematically correct ratio image height to display height. And yes.. you can get close... but there is no magic formula. The closest we have been able to get over the last 10 years of panorama work... is display to image height is 3:1 - image 1800 high... to display at 600 high
...>>>> if you only have a 600 high image... with out access to the original set of images from the camera... Then try displaying your image in a viewer that is only 200 pixels high.
