Colour_new_item = class 
	Menupullright (_ "_New") (_ "make a patch of colour") {
	Widget_colour_item = class 
		Menuaction (_ "_Colour") (_ "make a patch of colour") {
		action = Colour_picker "Lab" [50,0,0];
	}

	LAB_colour = class
		Menuaction (_ "CIE Lab _Picker") (_ "pick colour in CIE Lab space") {
		action = widget "Lab" [50, 0, 0];

		// ab_slice size
		size = 512;

		// range of values ... +/- 128 for ab
		range = 256;

		// map xy in slice image to ab and back
		xy2ab x = x / (size / range) - 128;
		ab2xy a = (a + 128) * (size / range);

		widget space default_value = class
			Colour space _result {
			_vislevel = 3;

			[_L, _a, _b] = default_value;
			L = Scale "Lightness" 0 100 _L;
			ab_slice = Image (lab_slice size L.value);
			point = Mark ab_slice (ab2xy _a) (ab2xy _b);

			_result = [L.value, xy2ab point.left, xy2ab point.top];

			Colour_edit colour_space value = widget colour_space value;
		}
	}

	CCT_colour = class
		Menuaction (_ "Colour from CCT") (_ "pick colour by CCT") {
		action = widget 6500;

		widget x = class
			_result {
			_vislevel = 3;

			T = Scale "CCT" 1800 25000 x;

			_result = colour_from_temp (to_real T);

			Colour_edit space value 
				= widget (temp_from_colour (Colour space value));
		}
	}
}

Colour_to_colour_item = class
	Menuaction (_ "Con_vert to Colour") (_ "convert anything to a colour") {
	action x = to_colour x;
}

#separator

Colour_convert_item = class
	Menupullright (_ "_Colourspace") (_ "convert to various colour spaces") {
	spaces = Image_type.image_colour_spaces;

	conv dest x = class
		_result {
		_vislevel = 3;

		to = Option_enum (_ "Convert to") spaces (spaces.get_name dest);

		_result = map_unary (colour_transform_to to.value_thing) x;
	}

	Mono_item = class
		Menuaction (_ "_Monochrome") (_ "convert to mono colourspace") {
		action x = conv Image_type.B_W x;
	}

	sRGB_item = class
		Menuaction (_ "_sRGB") (_ "convert to sRGB colourspace") {
		action x = conv Image_type.sRGB x;
	}

	scRGB_item = class
		Menuaction (_ "_scRGB") (_ "convert to scRGB colourspace") {
		action x = conv Image_type.scRGB x;
	}

	GREY16_item = class
		Menuaction (_ "_GREY16") (_ "convert to GREY16 colourspace") {
		action x = conv Image_type.GREY16 x;
	}

	RGB16_item = class
		Menuaction (_ "_RGB16") (_ "convert to RGB16 colourspace") {
		action x = conv Image_type.RGB16 x;
	}

	Lab_item = class
		Menuaction (_ "_Lab") (_ "convert to Lab colourspace (float Lab)") {
		action x = conv Image_type.LAB x;
	}

	LabQ_item = class
		Menuaction (_ "Lab_Q") (_ "convert to LabQ colourspace (32-bit Lab)") {
		action x = conv Image_type.LABQ x;
	}

	LabS_item = class
		Menuaction (_ "Lab_S") (_ "convert to LabS colourspace (48-bit Lab)") {
		action x = conv Image_type.LABS x;
	}

	LCh_item = class
		Menuaction (_ "L_Ch") (_ "convert to LCh colourspace") {
		action x = conv Image_type.LCH x;
	}

	XYZ_item = class
		Menuaction (_ "_XYZ") (_ "convert to XYZ colourspace") {
		action x = conv Image_type.XYZ x;
	}

	Yxy_item = class
		Menuaction (_ "_Yxy") (_ "convert to Yxy colourspace") {
		action x = conv Image_type.YXY x;
	}

	UCS_item = class
		Menuaction (_ "_UCS") (_ "convert to UCS colourspace") {
		action x = conv Image_type.UCS x;
	}
}

/* mark objects as being in various colourspaces
 */
Colour_tag_item = class
	Menupullright (_ "_Tag As") 
		(_ "tag object as being in various colour spaces") {
	spaces = Image_type.image_colour_spaces;

	tag dest x = class
		_result {
		_vislevel = 3;

		to = Option_enum (_ "Tag as") spaces (spaces.get_name dest);

		_result = map_unary (image_set_type to.value_thing) x;
	}

	Mono_item = class
		Menuaction (_ "_Monochrome") (_ "tag as being in mono colourspace") {
		action x = tag Image_type.B_W x;
	}

	sRGB_item = class
		Menuaction (_ "_sRGB") (_ "tag as being in sRGB colourspace") {
		action x = tag Image_type.sRGB x;
	}

	scRGB_item = class
		Menuaction (_ "_scRGB") (_ "tag as being in scRGB colourspace") {
		action x = tag Image_type.scRGB x;
	}

	RGB16_item = class
		Menuaction (_ "_RGB16") (_ "tag as being in RGB16 colourspace") {
		action x = tag Image_type.RGB16 x;
	}

	GREY16_item = class
		Menuaction (_ "_GREY16") (_ "tag as being in GREY16 colourspace") {
		action x = tag Image_type.GREY16 x;
	}

	Lab_item = class
		Menuaction (_ "_Lab") 
			(_ "tag as being in Lab colourspace (float Lab)") {
		action x = tag Image_type.LAB x;
	}

	LabQ_item = class
		Menuaction (_ "Lab_Q") 
			(_ "tag as being in LabQ colourspace (32-bit Lab)") {
		action x = tag Image_type.LABQ x;
	}

	LabS_item = class
		Menuaction (_ "Lab_S") 
			(_ "tag as being in LabS colourspace (48-bit Lab)") {
		action x = tag Image_type.LABS x;
	}

	LCh_item = class
		Menuaction (_ "L_Ch") (_ "tag as being in LCh colourspace") {
		action x = tag Image_type.LCH x;
	}

	XYZ_item = class
		Menuaction (_ "_XYZ") (_ "tag as being in XYZ colourspace") {
		action x = tag Image_type.XYZ x;
	}

	Yxy_item = class
		Menuaction (_ "_Yxy") (_ "tag as being in Yxy colourspace") {
		action x = tag Image_type.YXY x;
	}

	UCS_item = class
		Menuaction (_ "_UCS") (_ "tag as being in UCS colourspace") {
		action x = tag Image_type.UCS x;
	}
}

Colour_temperature_item = class
	Menupullright (_ "Te_mperature") 
		(_ "colour temperature conversions") {
	Whitepoint_item = class
		Menuaction (_ "_Move Whitepoint") (_ "change whitepoint") {
		action x = class
			_result {
			_vislevel = 3;

			old_white = Option_enum (_ "Old whitepoint") Whitepoints "D65";
			new_white = Option_enum (_ "New whitepoint") Whitepoints "D50";

			_result
				= map_unary process x
			{
				process im
					= im'''
				{
					im' = colour_transform_to Image_type.XYZ im;
					im'' = im' * 
						(new_white.value_thing / old_white.value_thing);
					im''' = colour_transform_to (get_type im) im'';
				}
			}
		}
	}

	D65_to_D50_item = class 
		Menupullright (_ "D_65 to D50") (_ "complex conversion") {
		XYZ_minimal_item = class
			Menuaction (_ "_Minimal") 
				(_ "D65 to D50 using the minimal 3x3 matrix in XYZ") {
			action x 
				= map_unary process x
			{
				process im
					= im'''
				{
					im' = colour_transform_to Image_type.XYZ im;
					im'' = recomb D652D50_direct im';
					im''' = colour_transform_to (get_type im) im'';
				}
			}
		}

		Bradford_item = class
			Menuaction (_ "_Bradford") (_ "D65 to D50 in Bradford cone space") {
			action x 
				= map_unary process x
			{
				process im
					= im'''
				{
					im' = colour_transform_to Image_type.XYZ im;
					im'' = im_D652D50 im';
					im''' = colour_transform_to (get_type im) im'';
				}
			}
		}
	}

	D50_to_D65_item = class 
		Menupullright (_ "D_50 to D65") (_ "complex conversion") {
		XYZ_minimal_item = class
			Menuaction (_ "_Minimal") 
				(_ "D50 to D65 using the minimal 3x3 matrix in XYZ") {
			action x 
				= map_unary process x
			{
				process im
					= im'''
				{
					im' = colour_transform_to Image_type.XYZ im;
					im'' = recomb D502D65_direct im';
					im''' = colour_transform_to (get_type im) im'';
				}
			}
		}

		Bradford_item = class
			Menuaction (_ "_Bradford") (_ "D60 to D65 in Bradford cone space") {
			action x 
				= map_unary process x
			{
				process im
					= im'''
				{
					im' = colour_transform_to Image_type.XYZ im;
					im'' = im_D502D65 im';
					im''' = colour_transform_to (get_type im) im'';
				}
			}
		}
	}

	Lab_to_D50XYZ_item = class
		Menuaction (_ "_Lab to D50 XYZ") 
			(_ "Lab to XYZ with a D50 whitepoint") {
		action x = map_unary (colour_unary im_D50Lab2XYZ) x;
	}

	D50XYZ_to_Lab_item = class
		Menuaction (_ "D50 _XYZ to Lab") 
			(_ "XYZ to Lab with a D50 whitepoint") {
		action x = map_unary (colour_unary im_D50XYZ2Lab) x;
	}

	sep1 = Menuseparator;

	CCT_item = class
		Menuaction (_ "Calculate temperature")
			(_ "estimate CCT using the McCamy approximation") {
		action z = map_unary temp_from_colour z;
	}

	Colour_item = Colour_new_item.CCT_colour;
}

Colour_icc_item = class
	Menupullright (_ "_ICC") (_ "transform with ICC profiles") {
	print_profile = 
		"$VIPSHOME/share/$PACKAGE/data/cmyk.icm";
	monitor_profile = 
		"$VIPSHOME/share/$PACKAGE/data/sRGB.icm";
	guess_profile image
		= print_profile, 
			has_type image && 
			get_type image == Image_type.CMYK &&
			has_bands image && 
			get_bands image >= 4
		= monitor_profile;
	render_intents = Option_enum (_ "Render intent") Render_intent.names
		(_ "Absolute");

	Export_item = class
		Menuaction (_ "_Export") (_ "export from PCS to device space") {
		action x = class
			_result {
			_vislevel = 3;

			profile = Pathname (_ "Output profile") print_profile;
			intent = render_intents;
			depth = Option (_ "Output depth") [_ "8 bit", _ "16 bit"] 0;

			_result 
				= map_unary process x
			{
				process image
					= icc_export [8, 16]?depth profile.value 
						intent.value_thing lab
				{
					lab = colour_transform_to Image_type.LABQ image;
				}
			}
		}
	}

	Import_item = class
		Menuaction (_ "_Import") (_ "import from device space to PCS") {
		action x = class
			_result {
			_vislevel = 3;

			embedded = Toggle (_ "Use embedded profile if possible") false;
			profile = Pathname (_ "Default input profile") (guess_profile x);
			intent = render_intents;

			_result 
				= map_unary process x
			{
				process image
					= icc_import_embedded intent.value_thing image,
						get_header_type "icc-profile-data" image != 0 &&
						embedded
					= icc_import profile.value intent.value_thing image;
			}
		}
	}

	Transform_item = class
		Menuaction (_ "_Transform") (_ "transform between two device spaces") {
		action x = class
			_result {
			_vislevel = 3;

			in_profile = Pathname (_ "Input profile") (guess_profile x);
			out_profile = Pathname (_ "Output profile") print_profile;
			intent = render_intents;

			_result
				= map_unary process x
			{
				process image
					= icc_transform in_profile.value out_profile.value 
						intent.value_thing image;
			}
		}
	}

	AC2RC_item = class
		Menuaction (_ "_Absolute to Relative") 
			(_ "absolute to relative colorimetry using device profile") {
		action x = class
			_result {
			_vislevel = 3;

			profile = Pathname (_ "Pick a profile") (guess_profile x);

			_result 
				= map_unary process x
			{
				process image
					= icc_ac2rc profile.value lab
				{
					lab = colour_transform_to Image_type.LAB image;
				}
			}
		}
	}
}

Colour_rad_item = class
	Menupullright (_ "_Radiance") (_ "convert to and from Radiance packed format") {
	Unpack_item = class
		Menuaction (_ "Unpack") 
			(_ "unpack Radiance format to float") {
		action x = map_unary rad2float x;
	}

	Pack_item = class
		Menuaction (_ "Pack") 
			(_ "pack 3-band float to Radiance format") {
		action x = map_unary float2rad x;
	}
}

#separator

Colour_dE_item = class
	Menupullright (_ "_Difference") (_ "calculate colour difference") {
	/* Apply a converter to an object ... convert image or colour (since
	 * we can guess the colour space we're converting from), don't convert
	 * matrix or vector (since we can't tell ... assume it's in the right
	 * space already).
	 */
	apply_cvt cvt x
		= cvt x, 
			is_Image x || is_Colour x || is_image x
		= x;

	diff cvt in1 in2 = abs_vec (apply_cvt cvt in1 - apply_cvt cvt in2);

	/* Converter to LAB.
	 */
	lab_cvt = colour_transform_to Image_type.LAB;

	/* Converter to UCS ... plain UCS is Ch form, so we go LAB again after
	 * to make sure we get a rectangular coord system.
	 */
	ucs_cvt = colour_transform Image_type.LCH Image_type.LAB @
		colour_transform_to Image_type.UCS;

	CIEdE76_item = class
		Menuaction (_ "CIE dE _76") 
			(_ "calculate CIE dE 1976 for two objects") {
		action a b = map_binary (diff lab_cvt) a b;
	}

	CIEdE00_item = class
		Menuaction (_ "CIE dE _00") 
			(_ "calculate CIE dE 2000 for two objects") {
		action a b = map_binary 
			(colour_binary (_ "im_dE00_fromLab") im_dE00_fromLab) a b;
	}

	UCS_item = class
		Menuaction (_ "_CMC(l:l)") (_ "calculate CMC(l:l) for two objects") {
		action a b = map_binary (diff ucs_cvt) a b;
	}
}

Colour_adjust_item = class
	Menupullright (_ "_Adjust") (_ "alter colours in various ways") {
	Recombination_item = class
		Menuaction (_ "_Recombination") 
			(_ "recombine colour with an editable matrix") {
		action x = class
			_result {
			_vislevel = 3;

			matrix 
				= Matrix_rec (identity_matrix (bands x))
			{
				// try to guess a sensible value for the size of the 
				// matrix
				bands x
					= x.bands, is_Image x || is_Colour x
					= x.width, is_Matrix x 
					= bands x.value?0, is_Group x
					= x.bands, has_member "bands" x
					= 3;
			}

			_result = map_unary (recomb matrix) x;
		}
	}

	Cast_item = class
		Menuaction (_ "_Cast") (_ "displace neutral axis in CIE Lab") {
		action x = class
			_result {
			_vislevel = 3;

			gr = Scale "Green-red" (-20) 20 0;
			by = Scale "Blue-yellow" (-20) 20 0;

			_result 
				= map_unary adjust_cast x
			{
				adjust_cast in
					= colour_transform_to (get_type in) in''
				{
					in' = colour_transform_to Image_type.LAB in;
					in'' = in' + 
						Vector [0, gr.value, by.value];
				}
			}
		}
	}

	HSB_item = class
		Menuaction (_ "_HSB") (_ "adjust hue-saturation-brightness in LCh") {
		action x = class
			_result {
			_vislevel = 3;

			h = Scale "Hue" 0 360 0;
			s = Scale "Saturation" 0.01 5 1;
			b = Scale "Brightness" 0.01 5 1;

			_result 
				= map_unary adjust_hsb x
			{
				adjust_hsb in
					= colour_transform_to (get_type in) in''
				{
					in' = colour_transform_to Image_type.LCH in;
					in'' = in' * Vector [b.value, s.value, 1] + 
						Vector [0, 0, h.value];
				}
			}
		}
	}
}

Colour_similar_item = class
	Menuaction (_ "_Similar Colour") (_ "find pixels with a similar colour") {
	action x = class
		_result {
		_vislevel = 3;

		target_colour = Colour_picker "Lab" [50, 0, 0];
		t = Scale "dE threshold" 0 100 10;

		_result
			= map_unary match x
		{
			match in 
				= abs_vec (in' - target) < t
			{
				target = colour_transform_to Image_type.LAB target_colour;
				in' = colour_transform_to Image_type.LAB in;
			}
		}
	}
}

#separator

Colour_chart_to_matrix_item = class
	Menuaction (_ "_Measure Colour Chart") 
		(_ "measure average pixel values for a colour chart image") {
	action x = class
		_result {
		_vislevel = 3;

		pacross = Expression (_ "Patches across chart") 6;
		pdown = Expression (_ "Patches down chart") 4;
		measure = Scale (_ "Measure area (%)") 1 100 50; 

        // get a representative image from an arg
        get_image x
            = get_image x.value?0, is_Group x
            = x;

        _im = get_image x; 
		sample = measure_draw (to_real pacross) (to_real pdown) 
				(to_real measure) _im;

		_result 
			= map_unary chart x
		{
			chart in
				= measure_sample (to_real pacross) (to_real pdown) 
					(to_real measure) in;
		}
	}
}

Colour_matrix_to_chart_item = class
	Menuaction (_ "Make Synth_etic Colour Chart") 
		(_ "make a colour chart image from a matrix of measurements") {
	action x = class
		_result {
		_vislevel = 3;

		pacross = Expression (_ "Patches across chart") 6;
		pdown = Expression (_ "Patches down chart") 4;
		pwidth = Expression (_ "Patch width in pixels") 50;
		pheight = Expression (_ "Patch height in pixels") 50;
		bwidth = Expression (_ "Border between patches") 0;

		_result 
			= map_unary build_chart x
		{
			build_chart in
				= Image (imagearray_assemble 
					(to_real bwidth) (to_real bwidth) patch_table)
			{
				// patch numbers for row starts
				rowstart = map (multiply (to_real pacross)) 
					[0 .. to_real pdown - 1];

				// assemble patches ... each one a pixel value
				patches = map (take (to_real pacross)) 
					(map (converse drop in.value) rowstart);

				// make an n-band constant image from eg. [1,2,3]
				// we don't know the format .. use sRGB (well, why not?)
				patch v = image_new (to_real pwidth) (to_real pheight) (len v) 
					Image_format.FLOAT Image_coding.NOCODING 
					Image_type.sRGB (Vector v) 0 0;

				// make an image for each patch
				patch_table = map (map patch) patches;
			}
		}
	}
}

Colour_plot_ab_scatter_item = class
	Menuaction (_ "_Plot ab Scatter") (_ "plot an ab scatter histogram") {
	action x = class
		_result {
		_vislevel = 3;

		bins = Expression (_ "Number of bins on each axis") 8;

		_result
			= map_unary plot_scatter x
		{
			plot_scatter in 
				= Image (bg * (((90 / mx) * hist) ++ blk))
			{
				lab = colour_transform_to Image_type.LAB in.value;
				ab = (unsigned char) ((lab?1 ++ lab?2) + 128);
				hist = hist_find_nD bins.expr ab;
				mx = max hist;
				bg = lab_slice bins.expr 1;
				blk = 1 + im_black (to_real bins) (to_real bins) 2;
			}
		}
	}
}