MaskTools2/Mt edge - Revision history

Reel.Deal: /* Syntax and Parameters */

2014-08-04T17:49:36Z

‎Syntax and Parameters

Reel.Deal: overhaul

2014-08-04T16:46:22Z

overhaul

Admin: 1 revision

2013-05-09T15:02:00Z

1 revision

88.114.121.83: Removed incorrect table. (The last coefficient wasn't 8, it was the normalization factor.)

2011-03-14T04:46:44Z

Removed incorrect table. (The last coefficient wasn't 8, it was the normalization factor.)

New page

{{FilterCat|External_filters|Other_filters|Support_filters}}

{{FuncDef|mt_edge (clip[, int "thY1"[, int "thY2"[, int "thC1"[, int "thC2"[, string "mode"]]]]])}}

'''Plugin''': [[MaskTools2]]

This filter creates an edge mask of the picture. The edge-finding algorithm uses a (3x3) convolution kernel, and the result of the convolution is then thresholded with <tt>thY1</tt> and <tt>thY2</tt> (luma) and <tt>thC1</tt> and <tt>thC2</tt> (chroma). The thresholding happens like that (r is the result of the convolution):

* r <= th1 gives 0.
* th1 < r <= th2 gives r.
* th2 < r gives 255.

<tt>mode</tt> choses the 3x3 convolution kernel used for the mask computing. There are three predefined kernel, "sobel", "roberts" and "laplace", and you can enter also a 3x3 custom kernel.
"sobel" uses the kernel "0 -1 0 -1 0 1 0 1 0",
{| class="wikitable" style="text-align: center; width: 100px; height: 100px;"
|-
| 0
| -1
| 0
|-
| -1
| 0
| 1
|-
| 0
| 1
| 0
|}

"roberts": "0 0 0 0 2 -1 0 -1 0"
{| class="wikitable" style="text-align: center; width: 100px; height: 100px;"
|-
| 0
| 0
| 0
|-
| 0
| 2
| -1
|-
| 0
| -1
| 0
|}

and "laplace": "1 1 1 1 -8 1 1 1 1".
{| class="wikitable" style="text-align: center; width: 100px; height: 100px;"
|-
| 1
| 1
| 1
|-
| 1
| -8
| 1
|-
| 1
| 1
| 1
|}

The normalization factor of the kernel is automatically computed and ceiled to the closest power of 2, to allow faster processing. You can specify your own normalization factor by adding it to the list of coefficients ( "1 1 1 1 -8 1 1 1 1 8" for example ).

Three new kernels have been introduced lately : "prewitt", "cartoon" and "min/max". "prewitt" is a more robust kernel, while "cartoon" behaves like "roberts", but takes only negative edges into account. Finally, "min/max" computes the local contrast ( local max - local min ).

More precisely, "hprewitt" is equivalent to :
mt_logic(mt_edge("1 2 1 0 0 0 -1 -2 -1 1"), mt_edge("1 0 -1 2 0 -2 1 0 -1 1"), mode = "max")

and "prewitt" is equivalent to
mt_logic(mt_logic(mt_edge("1 1 0 1 0 -1 0 -1 -1 1"), mt_edge("1 1 1 0 0 0 -1 -1 -1 1"), mode = "max"), mt_logic(mt_edge("1 0 -1 1 0 -1 1 0 -1 1"), mt_edge("0 -1 -1 1 0 -1 1 1 0 1"), mode = "max"), mode = "max")

'''Default Values:'''
* <tt>thY1</tt> = 10
* <tt>thY2</tt> = 20
* <tt>thC1</tt> = 10
* <tt>thC2</tt> = 20
* <tt>mode</tt> = "sobel"

----
Back to [[MaskTools2]].

@@ Line 22: / Line 22: @@
 ::{{Par2|mode|string|"sobel"}}
 :::{{Template:FuncDef3|mode}} chooses the 3x3 convolution kernel used for the mask computing.
-:::There are 7 predefined kernel, "sobel", "roberts", "laplace", "hprewitt", "prewitt", "cartoon" and "min/max".
+:::There are 7 predefined kernel, "sobel", "roberts", "laplace", "cartoon", "min/max", "hprewitt", and "prewitt".
 :::Additionally, you can also enter also a custom 3x3 kernel. The normalization factor of the kernel is automatically
 :::computed and ceiled to the closest power of 2, to allow faster processing. You can specify your own normalization
@@ Line 74: / Line 74: @@
 | 1
 |}
 :::*"hprewitt" is equivalent to:
@@ Line 80: / Line 84: @@
 :::* "prewitt" is a more robust kernel and is equivalent to:
 ::::<pre>mt_logic(mt_logic(mt_edge("1 1 0 1 0 -1 0 -1 -1 1"),mt_edge("1 1 1 0 0 0 -1 -1 -1 1"),mode="max"),mt_logic(mt_edge("1 0 -1 1 0 -1 1 0 -1 1"),mt_edge("0 -1 -1 1 0 -1 1 1 0 1"),mode="max"),mode="max")</pre>
 <br>
 ::{{Par2|thY1|int|10}}
@@ Line 90: / Line 90: @@
 ::{{Par2|thC2|int|10}}
 :::{{Template:FuncDef3|thY1}} and {{Template:FuncDef3|thY2}} are the low and high threshold for luma. {{Template:FuncDef3|thC1}} and {{Template:FuncDef3|thC2}} are the same but for chroma.
-:::Under thX1, the pixel is set to zero, over thX2, to 255, and in between, left untouched.
+:::If the pixel value is less than thX1, the pixel is set to 0, if it's greater than thX2 then it's set to 255, anything in between is left untouched.
 <br>
 ::{{Par2|Y|int|3}}

@@ Line 1: / Line 1: @@
 {{FilterCat|External_filters|Other_filters|Support_filters}}
-{{FuncDef|mt_edge (clip[, int "thY1"[, int "thY2"[, int "thC1"[, int "thC2"[, string "mode"]]]]])}}
+-----------------------------------------------
-'''Plugin''': [[MaskTools2]]
+:The thresholding happens like this (r is the result of the convolution):
-This filter creates an edge mask of the picture. The edge-finding algorithm uses a (3x3) convolution kernel, and the result of the convolution is then thresholded with <tt>thY1</tt> and <tt>thY2</tt> (luma) and  <tt>thC1</tt> and <tt>thC2</tt> (chroma). The thresholding happens like that (r is the result of the convolution):
+::* r <= th1 gives 0.
+::* th1 < r <= th2 gives r.
-* r <= th1 gives 0.
+::* th2 < r gives 255.
-* th1 < r <= th2 gives r.
+<br>
-* th2 < r gives 255.
+== Syntax and Parameters ==
+:{{Template:FuncDef|mt_edge (clip, string "mode", int "thY1", int "thY2", int "thC1", int "thC2", int "Y", int "U", int "V", string "chroma", int "offX", int "offY" int "w", int "h")}}
-<tt>mode</tt> choses the 3x3 convolution kernel used for the mask computing. There are three predefined kernel, "sobel", "roberts" and "laplace", and you can enter also a 3x3 custom kernel.
+<br>
-"sobel" uses the kernel "0 -1 0 -1 0 1 0 1 0",
+::{{Par2| |clip| }}
-{| class="wikitable" style="text-align: center; width: 100px; height: 100px;"
+:::Input clip
 |-
 | 0
@@ Line 26: / Line 41: @@
 | 1
 | 0
 |}
-"roberts": "0 0 0 0 2 -1 0 -1 0"
+:::*"roberts": "0 0 0 0 2 -1 0 -1 0"
-{| class="wikitable" style="text-align: center; width: 100px; height: 100px;"
+::::{| class="wikitable" style="text-align: center; width: 75px; height: 75px;"
 |-
 | 0
@@ Line 44: / Line 59: @@
 |}
-and "laplace": "1 1 1 1 -8 1 1 1 1".
+:::*"laplace": "1 1 1 1 -8 1 1 1 1"
-{| class="wikitable" style="text-align: center; width: 100px; height: 100px;"
+::::{| class="wikitable" style="text-align: center; width: 75px; height: 75px;"
 |-
 | 1
@@ Line 60: / Line 75: @@
 |}
-The normalization factor of the kernel is automatically computed and ceiled to the closest power of 2, to allow faster processing. You can specify your own normalization factor by adding it to the list of coefficients ( "1 1 1 1 -8 1 1 1 1 8" for example ).
+:::* "prewitt" is a more robust kernel and is equivalent to:
+::::<pre>mt_logic(mt_logic(mt_edge("1 1 0 1 0 -1 0 -1 -1 1"),mt_edge("1 1 1 0 0 0 -1 -1 -1 1"),mode="max"),mt_logic(mt_edge("1 0 -1 1 0 -1 1 0 -1 1"),mt_edge("0 -1 -1 1 0 -1 1 1 0 1"),mode="max"),mode="max")</pre>
-Three new kernels have been introduced lately : "prewitt", "cartoon" and "min/max". "prewitt" is a more robust kernel, while "cartoon" behaves like "roberts", but takes only negative edges into account. Finally, "min/max" computes the local contrast ( local max - local min ).
-−
-More precisely, "hprewitt" is equivalent to :
- mt_logic(mt_edge("1 2 1 0 0 0 -1 -2 -1 1"), mt_edge("1 0 -1 2 0 -2 1 0 -1 1"), mode = "max")
-−
-and "prewitt" is equivalent to
- mt_logic(mt_logic(mt_edge("1 1 0 1 0 -1 0 -1 -1 1"), mt_edge("1 1 1 0 0 0 -1 -1 -1 1"), mode = "max"), mt_logic(mt_edge("1 0 -1 1 0 -1 1 0 -1 1"), mt_edge("0 -1 -1 1 0 -1 1 1 0 1"), mode = "max"), mode = "max")
-−
-'''Default Values:'''
+:::*"cartoon" behaves like "roberts", but takes only negative edges into account.
-* <tt>thY1</tt> = 10
-* <tt>thY2</tt> = 20
-* <tt>thC1</tt> = 10
-* <tt>thC2</tt> = 20
-* <tt>mode</tt> = "sobel"
-----
+:::*"min/max" computes the local contrast (local max - local min).
-Back to [[MaskTools2]].
+<br>