B1: Filter > Deskew or Image > Deskew

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helmut
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B1: Filter > Deskew or Image > Deskew

Post by helmut »

The new function "Deskew" is used for de-skewing scanned grey-scale or black and white images. I wonder whether the main menu item "Filter > Deskew" is the right place. I would expect it in "Image > Deskew", where other menu items like "Rotate" are located.

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Last edited by helmut on Mon Dec 19, 2005 10:50 pm, edited 1 time in total.
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Clo
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and worse:::

Post by Clo »

• I agree, and besides, I guess that a more explicit term might be found : for instance, this is untranslatable correctly in French, it needs more explanations…
- In addition, "Deskew" is nowhere to be found in the dictionaries…
:mrgreen: G.
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Re: B1: [?] Filter > Deskew or Image > Deskew

Post by xnview »

helmut wrote:The new function "Deskew" is used for de-skewing scanned grey-scale or black and white images. I wonder whether the main menu item "Filter > Deskew" is the right place. I would expect it in "Image > Deskew", where other menu items like "Rotate" are located.
Ok
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helmut
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Re: and worse:::

Post by helmut »

Clo wrote:
- In addition, "Deskew" is nowhere to be found in the dictionaries…
Perhaps it's a bit clearer if "De-Skew" is used, analogue to "De-Interlace". What do English native speakers think about "De-Skew"?
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Post by Xyzzy »

Googlefight says:
112.000 for deskew, 137.000 for de-skew.
We've got a winner.

Btw, I cannot make it work. I select rectangle with top margin of skewed document, use Deskew and nothing happens...?

X.
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helmut
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Post by helmut »

Xyzzy wrote:Googlefight says:
112.000 for deskew, 137.000 for de-skew.
We've got a winner.
Good idea to use Googlefight. It will be "De-Skew", then.
Xyzzy wrote:Btw, I cannot make it work. I select rectangle with top margin of skewed document, use Deskew and nothing happens...?
If De-Skew can find a skewed horizontal line, it will work. Perhaps such a horizontal line was not recognized in your image. Reason might be to faint contrast (just guessing).

Perhaps De-Skew can be made a bit more verbose and report an error message if de-skewing could not be applied for some reason.
Some possible user messages:
- horizontal line was not recognized
- horizontal line was recognized, but is horizontal, already.
Xyzzy
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Post by Xyzzy »

Supported :!:

Edit: and still I cannot make it perform anything.

X.
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helmut
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Post by helmut »

In Beta 3 we have "De-Skew", which is good. But there are still no additional informational messages (see my previous post).

:arrow: Group "Confirmed/Reproduced"
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helmut
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Post by helmut »

In RC1 there is still no message box when De-Skew cannot de-skew when all lines are horizontal already or the selected area contains no contures to do de-skewing at all.

Still not fixed.
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Post by xnview »

helmut wrote:In RC1 there is still no message box when De-Skew cannot de-skew when all lines are horizontal already or the selected area contains no contures to do de-skewing at all.

Still not fixed.
I can't know when there is no horizontal line...
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Ty
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Deskew

Post by Ty »

I also have had trouble deskewing. In my case I'm trying to straighten a gray picture that is slightly tilted but which has no horizontal lines. So I can't use deskew.

I don't know if it would be worth the trouble for P to program, but I've seen a nice solution to this problem. When you click on "deskew", a little message pops up and says "draw a line that SHOULD be horizontal across the image," and then the cursor goes into a mode that allows the user to draw a line along some surface or edge. On <enter>, the program rotates the image so that line (which of course disappears) is now perfectly horizontal.

I find the "adjust by degrees" of the rotate function rather tedious, slow, imprecise and not verifiable.
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helmut
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Re: Deskew

Post by helmut »

Ty wrote:I also have had trouble deskewing. In my case I'm trying to straighten a gray picture that is slightly tilted but which has no horizontal lines. So I can't use deskew.
I guess "De-Skew" can't help you with that image.
Ty wrote:I don't know if it would be worth the trouble for P to program, but I've seen a nice solution to this problem. When you click on "deskew", a little message pops up and says "draw a line that SHOULD be horizontal across the image," and then the cursor goes into a mode that allows the user to draw a line along some surface or edge. On <enter>, the program rotates the image so that line (which of course disappears) is now perfectly horizontal.

I find the "adjust by degrees" of the rotate function rather tedious, slow, imprecise and not verifiable.
Good suggestions and comment. Suggestion Rotation based on the horizon line +auto-crop option is very related.