Hist_new_item = class
	Menupullright "_New" "new histogram" {
	Hist_item = class
		Menuaction "_Identity" "make an identity histogram" {
		action = class 
			_result {
			_vislevel = 3;

			d = Option "Depth" ["8 bit", "16 bit"] 0;
			_result = Plot [] ([im_identity 1, im_identity_ushort 1 65536]?d);
		}
	}

	Hist_new_from_matrix = Matrix_buildlut_item; 

	Hist_from_image_item = class
		Menuaction "Ta_g Image As Histogram" "set image Type to Histogram" {
		action x = hist_tag x;
	}

	Tone_item = class 
		Menuaction "_Tone Curve" "make a new tone mapping curve" {
		action = class
			_result {
			_vislevel = 3;

			d = Option "Depth" ["8 bit", "16 bit"] 0;
			b = Scale "Black point"  0 100 0;
			w = Scale "White point"  0 100 100;

			sp = Scale "Shadow point" 0.1 0.3 0.2;
			mp = Scale "Mid-tone point" 0.4 0.6 0.5;
			hp = Scale "Highlight point" 0.7 0.9 0.8;

			sa = Scale "Shadow adjust" (-15) 15 0;
			ma = Scale "Mid-tone adjust" (-30) 30 0;
			ha = Scale "Highlight adjust" (-15) 15 0;

			_result 
				= tone_build fmt b w sp mp hp sa ma ha
			{
				fmt = [Image_format.UCHAR, Image_format.USHORT]?d;
			}
		}
	}
}

Hist_convert_to_hist_item = class 
	Menuaction "Con_vert to Histogram" "convert anything to a histogram" {
	action x = hist_tag (to_image x);
}

Hist_find_item = class 
	Menupullright "_Find" "find a histogram" {
	Oned_item = class 
		Menuaction "_One Dimension" 
			"for a n-band image, make an n-band 1D histogram" {
		action x = map_unary hist_find x;
	}

	Nd_item = class 
		Menuaction "_Many Dimensions" 
			"for a n-band image, make an n-dimensional histogram" {
		action x = class 
			_result {
			_vislevel = 3;

			// default to something small-ish
			bins = Expression "Number of bins in each dimension" 8;

			_result 
				= map_unary process x
			{
				process in
					= hist_find_nD bins in;
			}
		}
	}

	Indexed_item = class
		Menuaction "_Indexed" 
			"use a 1-band index image to pick bins for an n-band image" {
		action x y 
			= map_binary map x y
		{
			map a b
				= hist_find_indexed index im
			{
				[im, index] = sortc (const is_index) [a, b];

				is_index x
					= has_image x && b == 1 && 
						(f == Image_format.UCHAR || f == Image_format.USHORT)
				{
					im = get_image x;
					b = get_bands x;
					f = get_format x;
				}
			}
		}
	}
}

Hist_map_item = class 
	Menuaction "_Map" "map an image through a histogram" {
	action x y
		= map_binary map x y
	{
		map a b
			= hist_map hist im
		{
			[im, hist] = sortc (const is_hist) [a, b];
		}
	}
}

Hist_eq_item = Filter_enhance_item.Hist_equal_item;

#separator

Hist_cum_item = class 
	Menuaction "_Integrate" 
		"form cumulative histogram" {
	action x = map_unary hist_cum x;
}

Hist_diff_item = class 
	Menuaction "_Differentiate" 
		"find point-to-point differences (inverse of Integrate)" {
	action x = map_unary hist_diff x;
}

Hist_norm_item = class 
	Menuaction "N_ormalise" "normalise a histogram" {
	action x = map_unary hist_norm x;
}

Hist_inv_item = class 
	Menuaction "In_vert" "invert a histogram" {
	action x = map_unary hist_inv x;
}

Hist_match_item = class 
	Menuaction "Ma_tch" 
		"find LUT which will match first histogram to second" {
	action in ref = map_binary hist_match in ref;
}

Hist_zerox_item = class 
	Menuaction "_Zero Crossings" "find zero crossings" {
	action x = class 
		_result {
		_vislevel = 3;

		edge = Option "Direction" [
			"Positive-going", 
			"Negative-going"
		] 0;

		_result 
			= map_unary (zerox (if edge == 0 then -1 else 1)) x;
	}
}

#separator

Hist_profile_item = class 
	Menuaction "Find _Profile" 
		"search from image edges for non-zero pixels" {
	action x = class  
		_result {
		_vislevel = 3;

		edge = Option "Search from" [
			"Top edge down", 
			"Left edge to right",
			"Bottom edge up",
			"Right edge to left"
		] 2;

		_result 
			= map_unary profile x
		{
			profile image
				= (Plot_histogram @ hist_tag) [
					profilemb 0 image.value,
					profilemb 1 image.value,
					profilemb 0 (fliptb image.value),
					profilemb 1 (fliplr image.value)
				]?edge;

			// im_profile only does 1 band images :-(
			profilemb d = bandjoin @ map (converse im_profile d) @ bandsplit;
		}
	}
}

Hist_project_item = class 
	Menuaction "Find Pro_jections" 
		"find horizontal and vertical projections" {
	action x = class {
		_vislevel = 2;

		_result = map_unary project x;

		// extract the result ... could be a group
		extr n
			= Plot_histogram _result?n, is_list _result
			= Group (map (Plot_histogram @ converse subscript n) _result.value);

		horizontal = extr 0;
		vertical = extr 1;
		centre = (gravity horizontal, gravity vertical);
	}
}

#separator

Hist_graph_item = class 
	Menuaction "P_lot Slice" "plot a slice along a guide or arrow" {
	action x = class 
		_value {
		_vislevel = 3;

		width = Scale "Width" 1 40 1;
		displace = Scale "Horizontal displace" (-50) 50 0; 
		vdisplace = Scale "Vertical displace" (-50) 50 0; 

		_value
			= map_unary graph x
		{
			graph arrow
				= hist_tag area'
			{
				area = extract_arrow 
					displace.value vdisplace.value width.value arrow;

				// squish vertically to get an average
				area' = resize Interpolate_bilinear 1 (1 / width.value) area;
			}
		}
	}
}

Extract_arrow_item = class 
	Menuaction "Extract _Arrow" "extract the area around an arrow" {
	action x = class 
		_value {
		_vislevel = 3;

		width = Scale "Width" 1 40 1;
		displace = Scale "Horizontal displace" (-50) 50 0; 
		vdisplace = Scale "Vertical displace" (-50) 50 0; 

		_value
			= map_unary (extract_arrow 
				displace.value vdisplace.value width.value) x;
	}
}

Hist_plot_item = class
	Menuaction "Plot _Object" 
		"plot an object as a bar, point or line graph" {
	action x = class
		_result {
		_vislevel = 3;

		format = Option_enum "Format" Plot_format.names "YYYY";
		style = Option_enum "Style" Plot_style.names "Line";

		auto = Toggle "Auto Range" true;
		xmin = Expression "X range minimum" 0;
		xmax = Expression "X range maximum" 1;
		ymin = Expression "Y range minimum" 0;
		ymax = Expression "Y range maximum" 1;

		_result
			= Plot options (image x)
		{
			options
				= [$style => style.value, $format => format.value] ++ range;
			range
				= [], auto
				= [$xmin => xmin.expr, $xmax => xmax.expr, 
					$ymin => ymin.expr, $ymax => ymax.expr]; 

			image x
				= image (extract_arrow 0 0 1 x), is_Arrow x
				= get_image x, has_image x
				= x2b im, b == 1
				= im
			{
				im = get_image (to_image x);
				w = get_width im;
				h = get_height im;
				b = get_bands im;

				// matrix to image makes a 1-band mxn image
				// we need to put columns into bands
				x2b im 
					= bandjoin (map extract_col [0 .. w - 1])
				{
						extract_col x = extract_area x 0 1 h im;
				}
			}
		}
	}
}
