Image view and Thumbnail don't match

thire · Post by **thire** » Sat Sep 24, 2005 8:33 pm

I just edited (cut und resampled) some pictures and saved them (everything with my favorite grafics proggy - guess

). And there seems to be a little problem with the browser thumbnails. Just look at my screenshot at http://fsmat.htu.tuwien.ac.at/~thire/web/Capture-2.png where everything is marked red. I send you the files if you want. (The black referee is not fliped! And: compare the other red thumbnail and the preview)
pressing F5 to refresh does not help.
any idea?
Thomas

marsh · Post by **marsh** » Sun Sep 25, 2005 1:31 am

Perhaps you are looking at original embedded thumbnail after changing picture?
These options are related:
Options>write>jpeg> [x] keep exif data -(and embedded thumbnails)
Options>browser>thumbnail> [x] Use embedded thumbnail selected.

thire · Post by **thire** » Sun Sep 25, 2005 6:47 am

I have these two options checked ([x]).

Post by **xnview** » Mon Sep 26, 2005 7:07 am

thire wrote:I have these two options checked ([x]).

Do you have used lossless crop?

thire · Post by **thire** » Mon Sep 26, 2005 10:16 am

I croped by choosing a rectangle and cutting it then. And then I saved with 80% quality in jpg.

Post by **xnview** » Mon Sep 26, 2005 10:53 am

thire wrote:I croped by choosing a rectangle and cutting it then. And then I saved with 80% quality in jpg.

Ok, so the embedded thumbnail is not updated...

thire · Post by **thire** » Mon Sep 26, 2005 3:17 pm

xnview wrote:
thire wrote:I croped by choosing a rectangle and cutting it then. And then I saved with 80% quality in jpg.
Ok, so the embedded thumbnail is not updated...

Which means? ...that my work (testing and reporting) is done and it's now your turn?

Guest · Post by **Guest** » Mon Sep 26, 2005 3:58 pm

Embedded thumbnails are sometimes attached to JPEG by camera in a part of file known as EXIF data. The little square icon on your thumbnails mean there is an embedded type inside JPEG. Unchecking options above may be useful to you (it helps thumbnail look like preview).

Post by **xnview** » Mon Sep 26, 2005 4:27 pm

thire wrote:
xnview wrote:
thire wrote:I croped by choosing a rectangle and cutting it then. And then I saved with 80% quality in jpg.
Ok, so the embedded thumbnail is not updated...
Which means? ...that my work (testing and reporting) is done and it's now your turn?

Currently XnView doesn't update embedded thumbnail in JPEG file after an operation like crop, brightness, ... So currently the only solution is to remove thumbnail, or to keep the current one

Olivier_G · Post by **Olivier_G** » Mon Sep 26, 2005 11:35 pm

Another solution is to uncheck this setting: Options>browser>thumbnail>'Use embedded thumbnail'
(you will loose 'speedy' creation of thumbnails, but get accurate/matching thumbnails in exchange... )

This is probably the best solution until most softwares (at least those you use) update adequately the embedded thumbnail.

Olivier

Sleepy · Post by **Sleepy** » Mon Oct 17, 2005 9:39 pm

Olivier_G wrote:Another solution is to uncheck this setting: Options>browser>thumbnail>'Use embedded thumbnail'
(you will loose 'speedy' creation of thumbnails, but get accurate/matching thumbnails in exchange... )

This is probably the best solution until most softwares (at least those you use) update adequately the embedded thumbnail.

Olivier

Thanks for your solution, Olivier_G.

However, I just found out a strange thing.
If I rotate pics in the browser, the thumbnails will rotate as well.
However, if I rotate pics in the viewer, the thumbnails will NOT rotate accordingly.

Does that mean the rotation in the browser will change the embedded thumbnail???

Thanks.

helmut · Post by **helmut** » Thu Oct 20, 2005 4:59 pm

Sleepy wrote:
Olivier_G wrote:Another solution is to uncheck this setting: Options>browser>thumbnail>'Use embedded thumbnail'
(you will loose 'speedy' creation of thumbnails, but get accurate/matching thumbnails in exchange... )

This is probably the best solution until most softwares (at least those you use) update adequately the embedded thumbnail.
...

However, I just found out a strange thing.
If I rotate pics in the browser, the thumbnails will rotate as well.
However, if I rotate pics in the viewer, the thumbnails will NOT rotate accordingly.

Does that mean the rotation in the browser will change the embedded thumbnail???

Thanks.

Rotation using JPG lossless rotation will rotate both image and thumbnail.

Whereas rotation in viewer is not lossless and will rotate the image, only. Currently, whenever applying filters, effetcs or other transformation, the embedded thumbnail will not be updated. One could say that this is a bug, at least there should be a way to update the embedded thumbnail.

The mismatch of image and embedded thumbnail can even be embarrassing, you can see and experience this in a research "Presentation of unwanted data/hidden in JPEG images" of the RWTH Aachen.