These are chat archives for openseadragon/openseadragon

28th
Jul 2015
Mark Salsbery
@msalsbery
Jul 28 2015 01:20
@iangilman Just an FYI, there’s some new issues with gestures in 2.0, so far only with touch. You can see it on iPhone and Windows 8+ with touch.
Digging...
Pinch zoom used to be one-to-one with contact points, now it drifts off :)(
Mark Salsbery
@msalsbery
Jul 28 2015 01:30
:worried:
Alcatrazer
@Alcatrazer
Jul 28 2015 07:34
Hi iangilman Sorry It was very late and I had to crash saw your message today.
Maybe later we can see how we can work on getting the tiles loaded status working. At the moment I am not very good at JS; just started but I'll read as we go.
javipsantos
@javipsantos
Jul 28 2015 07:53
Hello. My name is Javier and i am new with openseadragon.
Alcatrazer
@Alcatrazer
Jul 28 2015 08:03
Hi javipsantos
Even I just started using it. Wrote a tiny local webapp to help me practice art. It is really awesome. Only need to solve some problems.
Now the core of the app is working. Before iterations of the app used <img src> I had lots of scaling problems etc with that so decided to do a new fresh version with OSD
Only you need to generate DZI's first for the app to work.
DZI/ other tiling format.
javipsantos
@javipsantos
Jul 28 2015 08:06
Hi Alcatrazer

I have a basic question..... i have a gigaphoto composed over 160 pics, 100000 x 27000px, and i trying to use Deep Zoom Composer to split into DZI images. My question is which should be my starting point? I mean..... Photoshop doesn't allow me to save a jpeg.

I don't want to save a compressed LZW TIF, but i tried to. Photoshop allows me with a warning of 2GB image, BLA, BLA, BLA... but Deep Zoom Composer give me an error of "it's not a valid image format"

I reduced the image to 50000 x 13500 px but Deep Zoom Composer returns the same error.....
Alcatrazer
@Alcatrazer
Jul 28 2015 08:08
I am on linux I do not use the deep zoom composer. I used a program called vips. It is very powerful and fast.
javipsantos
@javipsantos
Jul 28 2015 08:09
ok, i have linux installed too so i will try
Alcatrazer
@Alcatrazer
Jul 28 2015 08:09
I think vips can run on windows too let me check. I hope you are comfortable with command prompt. Anyway we can try with vips python is too slow.
AH you also have linux then you are comfortable with CLI :)
javipsantos
@javipsantos
Jul 28 2015 08:09
i'm ok with commands
Alcatrazer
@Alcatrazer
Jul 28 2015 08:09
linux FS I noticed are also faster.
javipsantos
@javipsantos
Jul 28 2015 08:09
but the question is wich should be my starting point??
a tif 100000 x 27000 pixels compressed with LZW???
Alcatrazer
@Alcatrazer
Jul 28 2015 08:11
I've never worked with that large an image or specific com[ression algo's. I just use the defaults of vips. It compresses to JPEG. because they are tiles image data is less per tile so the total size of all teh tiles in a DZI tends to be smaller than the source image.
E.g. suppose one tile contains only white compression is huge there. So small savings per tile add up. You can experiment. JPEG is ok PNG will be heavier.
for local apps it does not matter.
or if the end user has very high bandwith. I get like 4mbps which is slow.
Algo will affect the render speed in browser too.
So optimise for what you need. Quality/speed
I dont know which file formats vips is fully compatible with. But you can use PNG that is lossless
javipsantos
@javipsantos
Jul 28 2015 08:15
Yes, ok. My point is bigger the starting image, better the resolution. photoshop doesn't allow to save a image that size in jpeg format............. so.... my first step, wil be try on linux with vips and let see.... thank you, i have to go now, but i will write later the result
Alcatrazer
@Alcatrazer
Jul 28 2015 08:15
majority of apps are compatible with PNG
javipsantos
@javipsantos
Jul 28 2015 08:15
but i can save from photoshop a PNG of JPG of that size
Alcatrazer
@Alcatrazer
Jul 28 2015 08:15
try PNG
or better make a PNG and TIFF and pass both through vips and see
javipsantos
@javipsantos
Jul 28 2015 08:16
i will try. Thank you. See you later
Alcatrazer
@Alcatrazer
Jul 28 2015 08:16
bye
vips gives no terminal output except errors during processing
that is normal.
Alcatrazer
@Alcatrazer
Jul 28 2015 11:40
What does OSD use for Ajax ? jquery ?
I don't know AJAX so just trying to learn it need it to extend functionality built around OSD.
Alcatrazer
@Alcatrazer
Jul 28 2015 12:19
hmm guess it uses xmlhttprequest directly
Mark Salsbery
@msalsbery
Jul 28 2015 13:31
Yes...OSD doesn't depend on any libraries.
Alcatrazer
@Alcatrazer
Jul 28 2015 13:37
msalsbery I want to learn AJAX but there is lots of confusing info out there can you recommend something.
Mark Salsbery
@msalsbery
Jul 28 2015 14:53
(Not a recommendation, but I use that site often for reference:))
There's tons of tutorials articles etc
Ian Gilman
@iangilman
Jul 28 2015 16:06
@Alcatrazer While OSD doesn't use jQuery, jQuery is a fine option for you to do AJAX on top of OSD.
javipsantos
@javipsantos
Jul 28 2015 19:02
@Alcatrazer i did it!!
Thank you for your help. Finally i used a Windows version of VIPS (only the laziness of not reboot the computer.....)
but all works fine. I used an uncompressed tif 50000 x 13000
I have to "fine tune" the final html. Thank you again
Mark Salsbery
@msalsbery
Jul 28 2015 19:05
:thumbsup: