I am seeding my layers as jpeg but always request pngs. Is this a terrible
thing to do. I need transparency and have limited disk space?
I would like to seed everything as png but the storage requirements are
5x-10x that of jpeg and I don't think I have enough disk space for all of my
data seeded as png. Am I losing any significant performance seeding as jpeg
and requesting png or mainly just losing some image quality?
Any thoughts or tips are appreciated.
Thanks!
Ashley
--
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You probably have PNGs on disk for all the tiles you have actually used, and you're not using the JPEG tiles for anything.
So you can delete the JPEG tiles and keep going without seeding if you haven't had performance issues so far. It's rare to use even 20% of the potential tiles.
-Arne
On 12/21/12 19:34 , mortac8 wrote:
I am seeding my layers as jpeg but always request pngs. Is this a terrible
thing to do. I need transparency and have limited disk space?
I would like to seed everything as png but the storage requirements are
5x-10x that of jpeg and I don't think I have enough disk space for all of my
data seeded as png. Am I losing any significant performance seeding as jpeg
and requesting png or mainly just losing some image quality?
Any thoughts or tips are appreciated.
Thanks!
Ashley
So if I seed as JPEG but always request PNG, does it just not use the GeoWebCache in that case (or does it convert the cached tiles to PNG on the fly)?
On 12/25/2012 6:48 PM, Arne Kepp wrote:
You probably have PNGs on disk for all the tiles you have actually used, and you're not using the JPEG tiles for anything.
So you can delete the JPEG tiles and keep going without seeding if you haven't had performance issues so far. It's rare to use even 20% of the potential tiles.
-Arne
On 12/21/12 19:34 , mortac8 wrote:
I am seeding my layers as jpeg but always request pngs. Is this a terrible
thing to do. I need transparency and have limited disk space?
I would like to seed everything as png but the storage requirements are
5x-10x that of jpeg and I don't think I have enough disk space for all of my
data seeded as png. Am I losing any significant performance seeding as jpeg
and requesting png or mainly just losing some image quality?
Any thoughts or tips are appreciated.
Thanks!
Ashley
--
Ashley Mort
Sr. Software Engineer
Raytheon - Intelligence and Information Systems
972-205-5165 (office)
814-571-3039 (cell)
GWC is used, but the tiles that you seeded are not.
If you request a tile that does not exist in the cache, GWC will ask GeoServer to render it and then store the result (a PNG, in your case) in case someone else requests the same tile again.
In most cases this type of caching (on the fly, as needed) is the best option anyway. Seeding is only important when updating tiles or when WMS can't keep up with realistic traffic loads.
The JPEG tiles you seeded are just wasting space. Once you save an image as JPEG the alphachannel (transparency) is lost, so they cannot be used to make PNGs.
(It's also possible to mix JPEGs and PNGs to get both transparency where needed and good compression, but nobody funded the proposals to implement such a feature.)
-Arne
On 1/2/13 16:44 , Ashley Mort wrote:
So if I seed as JPEG but always request PNG, does it just not use the GeoWebCache in that case (or does it convert the cached tiles to PNG on the fly)?
On 12/25/2012 6:48 PM, Arne Kepp wrote:
You probably have PNGs on disk for all the tiles you have actually used, and you're not using the JPEG tiles for anything.
So you can delete the JPEG tiles and keep going without seeding if you haven't had performance issues so far. It's rare to use even 20% of the potential tiles.
-Arne
On 12/21/12 19:34 , mortac8 wrote:
I am seeding my layers as jpeg but always request pngs. Is this a terrible
thing to do. I need transparency and have limited disk space?
I would like to seed everything as png but the storage requirements are
5x-10x that of jpeg and I don't think I have enough disk space for all of my
data seeded as png. Am I losing any significant performance seeding as jpeg
and requesting png or mainly just losing some image quality?
Any thoughts or tips are appreciated.
Thanks!
Ashley