Instant Low-res image like Picasa 3

[Zarxrax]

Someone who probably knows what he's talking about just told me that you can probably get the fast small blurry previews on jpegs by discarding the high frequency coefficients and not performing idct.

I'm not sure if xnview uses it's own decoders though, as this would require changing the code that decodes the images.

[thibaud]

I think you just described FastPictureViewer: http://www.fastpictureviewer.com/
It doesn't have any sort of browsing or thumbnails, but its straightforward and damn fast.

Thanks a lot for the info. I had never heard of it. it looks extremely capable and highly optimized (gpu extensions support, multithread decoding, yum yum)
unfortunately it's supported image formats doesn't meet my expectation (and actually doesn't expand much onto what picasa 3 already support)

Actually xnview is the ONLY windows image viewer I know off which support (.exr, .hdr, .rpf, ) which are some of the main format used in the cgi industry.
btw, I just stumbled on this interesting Wikipedia comparison of image viewers that might need some editing.

[oops66]

I moved them all to another folder, and the viewer still functioned normally, and it did not try to recreate any of the files.

Maybe because you have checked the picasa v3 folder manager option " scan once" instead "scan always" ?

So how is the viewer getting the smaller thumbnails? This is interesting.

Maybe the embedded thumbnails ?

PS: Interesting this Wikipedia link thibaud : here , (just need to be updated)

[xnview]

For me Picasa store low res in DB, Picasa don't use standard GUI component, but a rewrited GUI based on DirectX, and one thing i have not the same financial or development means as Picasa, ACDsee, ....

[Zarxrax]

Maybe because you have checked the picasa v3 folder manager option " scan once" instead "scan always" ?

Nope, the main picasa 3 application would rebuild the thumbnails if I ran it, the picasa image viewer did not though, so the image viewer is able to function properly without any thumbnails stored in database.

Maybe the embedded thumbnails ?

I was testing with new jpeg images created in photoshop, and I'm pretty sure it doesn't embed thumbnails in them (maybe I'm wrong?).

[helmut]

JPG format allows for embedding a thumbnail, so perhaps Picasa reads that thumbnail and displays it as a lowres preview.

Perhaps an easy way to check:
Does the lowres preview work for all image types (JPG, GIF, PNG, BMP, TIF) or is it just for JPG images?

[thibaud]

and one thing i have not the same financial or development means as Picasa, ACDsee, .... Smile

I think everybody here is aware that google != Pierre.
I certainly didn't mean to bring both application to a confrontation.

I would just like to encourage you once again with xnviewMP development (which looks absolutely great so far)

And, like I probably already said..
"Details", like performance improvements (which I'm aware can take up a lot of development resources) are definitely the kind of attention I would love to see carried into xnviewMP development at some stage.

[Zarxrax]

It takes some time for it to generate thumbnails for a png, it seems. It does jpegs IMMEDIATELY though. But as I said, I'm fairly certain that none of my jpegs contain thumbnails embedded inside.

I start up picasa image viewer, and about 1 second later, it will spit out thumbnails for about 18 jpegs (almost 200mb of combined data), then when it gets to some large png files, it takes it about 1-2 seconds to come up with a thumbnail for them.

I also determined that picasaphotoviewer.exe can function just as long as you keep the file \runtime\slingshot\respack.yt

[Zarxrax]

If the creator of xnviewmp is interested in creating the fast jpeg thumbnails, I have found that there is a library called epeg which does it and claims to be the fastest in existence. I would guess Picasa is either using this library or a very similar method of decoding the jpegs.

[xnview]

If the creator of xnviewmp is interested in creating the fast jpeg thumbnails, I have found that there is a library called epeg which does it and claims to be the fastest in existence. I would guess Picasa is either using this library or a very similar method of decoding the jpegs.

Ok, thanks, i'll take a look

[XnTriq]

Loading of images on Picasa Web Albums seems to work like an ajaxified version of the deprecated LOWSRC attribute for the IMG tag in HTML 3.2.

This is an example from caracole's album “Xnview”:

• s72 (72×42)
  s94 (94×55)
  s110 (110×64)
  s128 (128×75)
  s144 (144×84)
  s160 (160×94)
  s220 (220×129)
  s288 (288×169)
  s640 (556×327)
  Fullsize (556×327)

Move the knob on the slider to see the effect.

[XnTriq]

• OpenZoom
  OpenZoom is an Open Source SDK for Multiscale Images and Zoomable User Interfaces.

• GigaPan.org
  The GigaPan(SM) process allows users to upload, share, and explore brilliant gigapixel+ panoramas from around the globe.

• Zoomorama
  Zoomorama allows users to create their own online magazines, or Zoomazines™, by pasting images, texts and soon, videos. The company seeks to produce a LIFE magazine type of experience online.

• Microsoft
  • Live Labs: Introducing Seadragon.com
    Smooth, seamless browsing of vast quantities of visual information, on wall sized displays or mobile devices, regardless of the amount of data.
  • DeepZoomPix (technology demonstration available until 31/Dec/2009)
    DeepZoomPix enables you to explore and share photos in a new and interactive way.

• UCL Centre for Advanced Spatial Analysis
  • Google Maps Image Cutter
    The Google Map Image Cutter is an application designed to take any image or digital photo and cut it into tiles which are displayed on a Google Map. Using this tool, large images can be published on the web in a format that allows the user to pan and zoom using the standard Google Maps interface. Although publishing large digital photos is the most obvious application, this technique can also be used for annotated maps of an area that are not to scale e.g. directions for how to get to the office.

• Daniel Gasienica
  • Inline Multiscale Image Replacement

• SilverlightShow
  • The Making of Deep Zoom Obama

• Wikipedia
  • Mipmap
  • Scale space
  • Pyramid (image processing)
  • Gaussian Pyramid
  • Zoomable user interface

[xnview]

If the creator of xnviewmp is interested in creating the fast jpeg thumbnails, I have found that there is a library called epeg which does it and claims to be the fastest in existence. I would guess Picasa is either using this library or a very similar method of decoding the jpegs.

I've tested epeg, and my library has the same speed...

[thibaud]

hi Pierre,
glad to hear you investigating performance improvements... how is MP development going on ?
did you by any chance manage to implement some enhanced loading behavior (with instant preview) ?

[xnview]

hi Pierre,
glad to hear you investigating performance improvements... how is MP development going on ?
did you by any chance manage to implement some enhanced loading behavior (with instant preview) ?

Yes, i have made something, i'll post a new alpha in september...