Video contact sheet: Thumbnail truncated

Bugs and Suggestions in XnView Classic which have been resolved

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helmut
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Location: Frankfurt, Germany

Video contact sheet: Thumbnail truncated

Post by helmut » Wed Feb 27, 2008 6:07 pm

When creating a video contact sheet (Create > Video thumbnail gallery...) with specific setting a thumbnail is truncated.

Settings used:
Width 1024
Columns: 2
Spacing: 0
Rows: 2

The video contact sheet generated contains 4 thumbnails which are all in a line. (Bug :bug: - should be two rows). The thumbnail at the very right is truncated, only about 10% of the thumbnail can be seen.

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xnview
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Re: Video contact sheet: Thumbnail truncated

Post by xnview » Wed Feb 27, 2008 7:25 pm

Right
Pierre.

Danny
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Joined: Sat Sep 04, 2004 5:09 pm

Post by Danny » Mon Dec 01, 2008 6:18 pm

This still doesn't work right as of v1.95.4.

Take a video of your choice and set the columns and rows fields to:
  • unequal values and
  • not the same as the video's aspect ratio
and chances are high, that there will be missing frames. For example:
  • contact sheet width: 1024
  • columns: 5
  • rows: 3
  • (video aspect: 4:3)
My guess is that there might be some rounding issues. As you can see in the image i've attached, the 2 missing screens at the end are sitting to the right, being truncated:

Image

If you use the same value for columns and rows or the aspect ratio of the video (4 coumns and 3 rows) it'll fit - from what i've tested.
Get the bugs fixed, THEN start adding features. It sucks, but someone has to do it.

Danny
Posts: 564
Joined: Sat Sep 04, 2004 5:09 pm

Post by Danny » Tue Dec 16, 2008 3:58 pm

So, has anyone tried this? Any confirmation?

I thought it through once more, and i'm pretty confident it's a rounding issue. If the result of the resizing procedure doesn't result in an integer, it'll be impossible to exactly fit the images into their place.

The procedure is probably just rounding, while it should always round up and then, at the end of it, crop the image to specified width, with top left alignment. It shouldn't end up with more than 2 pixels cropped ever. But there will be no more missing screenshots.
Get the bugs fixed, THEN start adding features. It sucks, but someone has to do it.

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xnview
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Re: Video contact sheet: Thumbnail truncated

Post by xnview » Fri Jan 09, 2009 10:57 am

Please try XnView 1.96 beta
Pierre.

Danny
Posts: 564
Joined: Sat Sep 04, 2004 5:09 pm

Re: Video contact sheet: Thumbnail truncated

Post by Danny » Sun Jan 25, 2009 1:33 pm

xnview wrote:Please try XnView 1.96 beta
In beta2 there seem to be no more missing frames. Thanks for fixing that.
Get the bugs fixed, THEN start adding features. It sucks, but someone has to do it.

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