Crop overscan in Extract Review

[iLLiCiTiT]

Description

• added ability to define Overscan Crop for input in ExtractReview plugin
• input field is string where is possible to define how crop will work
  • value may cause that resolution will be expanded instead of cropped
  • crop may be explicit or relative, in pixels or percents
  • added special percent case -10%+ (10 is random number) which says that input resoltuion is 110% of expected output (input width 2200px -> output width 2000px)
  • value may containt 2 values one for width second for height
  • all values are center related == +300px will add 150px on both sides and keep center in center
  • filters should only crop or expand resolution (not rescale)

Example variants with description

String	Output	Description
	2200px	Empty string keep resolution unchanged.
50%	1100px	Crop 25% of input width on left and right side.
300px	300px	Keep 300px in center of input and crop rest on left and right.
300	300px	Values without units are used as pixels (px).
0px	0px	Invalid value.
+0px	2200px	Keep resolution unchanged.
+300px	2500px	Add black pillars of 150px width on left and right side.
-300px	1900px	Crop 150px on left and right side
+10%	2420px	Add black pillars of 5% size of input on left and right side.
-10%	1980px	Crop 5% of input size by on left and right side.
-10%+	2000px	Input width is 110% of output width.

Closes https://github.com/pypeclub/client/issues/53#issuecomment-846796817

[mkolar]

Syntax for reversing the overscan using -10%+ us not working. Instead it actually expands the result by 10% while keeping the same resolution.

[mkolar]

see comment about the -+ syntax.

Secondly Please move the crop settings above the resolution. They are processed in order, it would be good to set them in order too.

Lastly, can we make 0 value do nothing instead of being invalid? Same as with resolution if the setting is 0 or empty it should be considered the same - disabled

[hound]

invalid escape sequence '\g'

[iLLiCiTiT]

see comment about the -+ syntax.

Swapped +/- in code. Fixed.

Secondly Please move the crop settings above the resolution

Done

Lastly, can we make 0 value do nothing instead of being invalid?

Done. Additional question, what if output is smaller than 0px? (Small chance but possible...)