SkewRows - Revision history

Reel.Deal: add link to avs+ documentation

2022-09-18T05:12:59Z

add link to avs+ documentation

← Older revision		Revision as of 07:12, 18 September 2022
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			<div {{BlueBox2\|40\|0\|3px solid purple}} >
			{{AvsPlusFullname}}<br>
			Up-to-date documentation: [https://avisynthplus.readthedocs.io/en/latest/avisynthdoc/corefilters/skewrows.html https://avisynthplus.readthedocs.io]
			</div>


	{{Template:FuncDef\|SkewRows(clip ''clip'', int ''skew'')}}		{{Template:FuncDef\|SkewRows(clip ''clip'', int ''skew'')}}

Raffriff42: /* See also */ ...with bad codecs

2016-01-25T00:41:22Z

Raffriff42: formatting, links, phrasing

2016-01-18T04:16:00Z

formatting, links, phrasing

← Older revision		Revision as of 06:16, 18 January 2016
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	{{Template:FuncDef\|SkewRows(clip ''clip'', int ''skew'')}}		{{Template:FuncDef\|SkewRows(clip ''clip'', int ''skew'')}}

	~~SkewRows (added in v2.60) skews~~ the rows of a clip ~~by an amount of~~ ''~~skew~~''~~. The skewing is memory layout based, so RGB images are skewed from the bottom up, YUV images are skewed from~~ the ~~top down~~.		''Skews'' the rows of a clip. It can be used to correct (''deskew'') problem clips such as the [[MessageClip\|error message]] shown below.

	It can be ~~used to read those skewed error messages that some media player users are submitting~~.		The amount, {{FuncArg\|skew}}, can be positive or negative. For [[YUY2]] sources, {{FuncArg\|skew}} should be even (divisible by 2).

	~~The effect of the algorithm is to paste all of the input rows together as one single very long row~~, ~~then slice them up based on the new width (= input width + skew)~~. ~~Skew can also be negative in which case~~ the ~~last skew pixels of each line~~ are ~~added to~~ the ~~beginning of the next line and you get some extra lines at the end. The last line is padded with grey pixels when required~~.		All [[Interleaved\|interleaved]] pixel formats are supported, including [[Y8]]. [[RGB]] images are skewed from the bottom up, while [[YUV]] images are skewed from the top down.

	~~The geometry~~ of the ~~output is calculated~~ as ~~follows:~~		All of the input rows are joined together as one very long row, then sliced up based on the new width (= input width + {{FuncArg\|skew}}).
	* OutWidth = ~~InWidth~~ + skew ~~// signed skew values acceptable~~
	* OutHeight = (InHeight*InWidth + OutWidth-1) ~~/ OutWidth // rounded up to nearest integer~~

	~~All interleaved pixel formats~~ are ~~supported (including Y8), though~~ ''skew~~'' should be even for YUY2~~.		The '''width and height of the output clip are therefore altered slightly''', as follows:
			* <tt>OutWidth = InWidth + {{FuncArg\|skew}}  </tt> (signed skew values acceptable)
			* <tt>OutHeight=(InHeight*InWidth+OutWidth-1)/OutWidth </tt> (rounded up to nearest integer)
			The last line is padded with grey pixels when required.

			==== Examples ====

	~~'''examples:'''~~		{\|border="0"

	{\|border=~~1 cellspacing=1 cellpadding=4~~
	\| [[Image:Skewrows_before.png]]		\| [[Image:Skewrows_before.png]]
			\|-
			\|align="center"\| (original with skew problem)
			\|-
			\|
			\|-
	\| [[Image:Skewrows_after.png]]		\| [[Image:Skewrows_after.png]]
	\|-		\|-
	\| ~~Original~~		\|align="center"\| <tt>SkewRows(1)</tt>
	\| SkewRows(1)
	\|}		\|}

			==== See also ====
	~~'''~~See also~~'''~~

	[[AviSource]] and [[DirectShowSource]] {{FuncArg\|pixel_type}}		[[AviSource]] and [[DirectShowSource]] {{FuncArg\|pixel_type}}
	<div {{NotaBeneWidthIndent\|56\|2\|2px solid gray}} >		<div {{NotaBeneWidthIndent\|56\|2\|2px solid gray}} >
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	</div>		</div>

			==== Changelog ====
	~~'''changelog:'''~~

	{\| border="1"		{\| border="1"

Raffriff42: add note re: pixel_type=+X

2016-01-18T04:15:05Z

add note re: pixel_type=+X

← Older revision		Revision as of 06:15, 18 January 2016
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	All interleaved pixel formats are supported (including Y8), though ''skew'' should be even for YUY2.		All interleaved pixel formats are supported (including Y8), though ''skew'' should be even for YUY2.


	'''examples:'''		'''examples:'''
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	\| SkewRows(1)		\| SkewRows(1)
	\|}		\|}


			'''See also'''

			[[AviSource]] and [[DirectShowSource]] {{FuncArg\|pixel_type}}
			<div {{NotaBeneWidthIndent\|56\|2\|2px solid gray}} >
			''For planar color formats, adding a '+' prefix, e.g. DirectShowSource(..., pixel_type="+YV12"), tells AviSynth the video rows are DWORD aligned in memory instead of packed. '''This can fix skew or tearing of the decoded video''' when the width of the picture is not divisible by 4. ''
			</div>


	'''changelog:'''		'''changelog:'''

Raffriff42: added category

2015-11-08T15:00:42Z

added category

← Older revision		Revision as of 17:00, 8 November 2015
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	[[Category:Internal filters]]		[[Category:Internal filters]]
			[[Category:Transformation]]

Admin: 1 revision

2013-05-09T15:02:28Z

1 revision

← Older revision	Revision as of 17:02, 9 May 2013
(No difference)

Wilbert at 21:43, 8 January 2011

2011-01-08T21:43:04Z

New page

{{Template:FuncDef|SkewRows(clip ''clip'', int ''skew'')}}

SkewRows (added in v2.60) skews the rows of a clip by an amount of ''skew''. The skewing is memory layout based, so RGB images are skewed from the bottom up, YUV images are skewed from the top down.

It can be used to read those skewed error messages that some media player users are submitting.

The effect of the algorithm is to paste all of the input rows together as one single very long row, then slice them up based on the new width (= input width + skew). Skew can also be negative in which case the last skew pixels of each line are added to the beginning of the next line and you get some extra lines at the end. The last line is padded with grey pixels when required.

The geometry of the output is calculated as follows:
* OutWidth = InWidth + skew // signed skew values acceptable
* OutHeight = (InHeight*InWidth + OutWidth-1) / OutWidth // rounded up to nearest integer

All interleaved pixel formats are supported (including Y8), though ''skew'' should be even for YUY2.

'''examples:'''

{|border=1 cellspacing=1 cellpadding=4
| [[Image:Skewrows_before.png]]
| [[Image:Skewrows_after.png]]
|-
| Original
| SkewRows(1)
|}

'''changelog:'''

{| border="1"
|-
| v2.60
| Initial release
|}

[[Category:Internal filters]]

← Older revision		Revision as of 02:41, 25 January 2016
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	[[AviSource]] and [[DirectShowSource]] {{FuncArg\|pixel_type}}		[[AviSource]] and [[DirectShowSource]] {{FuncArg\|pixel_type}}
	<div {{NotaBeneWidthIndent\|56\|2\|2px solid gray}} >		<div {{NotaBeneWidthIndent\|56\|2\|2px solid gray}} >
	''For planar color formats, adding a '+' prefix, e.g. DirectShowSource(..., pixel_type="+YV12"), tells AviSynth the video rows are DWORD aligned in memory instead of packed. '''This can fix skew or tearing of the decoded video''' when the width of the picture is not divisible by 4. ''		''For planar color formats, adding a '+' prefix, e.g. DirectShowSource(..., pixel_type="+YV12"), tells AviSynth the video rows are DWORD aligned in memory instead of packed. '''This can fix skew or tearing of the decoded video''' with bad codecs when the width of the picture is not divisible by 4. ''
	</div>		</div>