/usr/share/nip2/compat/7.16/_joe_utilities.def is in nip2 7.26.3-1build1.
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*
* so_balance ref_meanmax im1 im2 mask blur gauss *
* nonzero_mean im = no_out *
* so_meanmax im = result *
* so_calculate ref_meanmax im mask = result *
* simple_frame frame im_w im_h ov cs ms bf option = result *
* corner_frame frame im_w im_h ov cs ms bf = result *
* build_frame r_tl r_tr r_bl r_br r_mt r_mb r_ml r_mr im_w im_h ov bf = result *
* complex_frame frame im_w im_h ov cs es ms bf option= result *
* complex_edge ra rb t bl d = rc *
* frame_lr_min r_l r_r target bw = result *
* frame_tb_min r_t r_b target bw = result *
* frame_position_image im ref os colour= result *
* merge_array bw arr = result *
* merge_to_scale im target blend dir = result *
* select_ellipse line width = mask *
* select_tetragon p1 p2 p3 p4 = mask *
* select_polygon pt_list = mask *
* perspective_transform to from = trans'' *
* sort_pts_clockwise l = l'' *
*/
/* Called from:
* _NG_Extra.def Clone_area_item
*/
so_balance ref_meanmax im1 im2 mask gauss
= result
{
//ref_meanmax = so_meanmax im1;
so_values = so_calculate ref_meanmax im2 mask;
im2_cor_a = clip2fmt im2.format im2'', has_member "format" im2
= im2''
{im2'' = im2 * (so_values?0) + (so_values?1);}
// Option to convert replacement image to scaled gaussian noise
im2_cor = im2_cor_a, gauss == false
= clip2fmt im2_cor_a.format gauss_im
{gauss_im =
im_gaussnoise im2_cor_a.width im2_cor_a.height ref_meanmax?0
(deviation im2_cor_a);}
result = im_blend (get_image mask) (get_image
im2_cor) (get_image im1);
};
////////////////////////////////////////////////////////////////////////////////
/* Calculates the mean of the non zero pixels.
*
* Called from:
* _NG_utilities so_meanmax
*/
nonzero_mean im = no_out
{
zero_im = (im == 0);
zero_mean = mean zero_im;
no_mean = mean im;
no_out = no_mean/(1 - (zero_mean/255));
};
////////////////////////////////////////////////////////////////////////////////
/* Calculates the max and nonzero mean of an image
*
* Called from:
* _NG_utilities so_balance
* _NG_utilities so_calculate
* _NG_Extra.def Clone_area_item
* _NG_Extra.def Balance_item.Balance_find_item
*/
so_meanmax im = result
{
mean_of_im = nonzero_mean im;
adjusted_im = im - mean_of_im;
max_of_im = max adjusted_im;
result = [mean_of_im, max_of_im];
};
////////////////////////////////////////////////////////////////////////////////
/* Calculates the scale and offset required to match a reference mean and max
*
* Called from:
* _NG_utilities so_balance
* _NG_Extra.def Balance_item.Balance_find_item
*/
so_calculate ref_meanmax im mask = result
{
im' = if mask then im else 0;
im_values = so_meanmax im';
mean_of_ref = ref_meanmax?0;
mean_of_im = im_values?0;
max_of_ref = ref_meanmax?1;
max_of_im = im_values?1;
scale = (max_of_ref)/(max_of_im);
offset = mean_of_ref - (mean_of_im * scale);
result = [ scale, offset ];
};
////////////////////////////////////////////////////////////////////////////////
/* Extends or shortens the central sections of a simple frame to fit round a given image.
*
* Called from:
* _NG_Extra.def Frame_item.Simple_frame_item
*/
simple_frame frame im_w im_h ov cs ms bf option = result
{
cs' = (1 - cs);
ms' = (0.5 - (ms/2));
ms'' = (1 - cs);
//Regions
r_tl = Region_relative frame 0 0 cs cs;
r_tr = fliplr r_tl, option == true
= Region_relative frame cs' 0 cs cs;
r_bl = Region_relative frame 0 cs' cs cs;
r_br = fliplr r_bl, option == true
= Region_relative frame cs' cs' cs cs;
r_mt = Region_relative frame ms' 0 ms cs;
r_mb = Region_relative frame ms' ms'' ms cs;
r_ml = Region_relative frame 0 ms' cs ms;
r_mr = fliplr r_ml, option == true
= Region_relative frame ms'' ms' cs ms;
result = build_frame r_tl r_tr r_bl r_br r_mt r_mb r_ml r_mr im_w im_h ov bf;
};
////////////////////////////////////////////////////////////////////////////////
/* Copies and extends a simple frame corner to produce a complete frame to fit round a given image.
*
* Called from:
* _NG_Extra.def Frame_item.Frame_corner_item
*/
corner_frame frame im_w im_h ov cs ms bf = result
{
cs' = (1 - cs);
ms' = (0.5 - (ms/2));
//Regions
r_tl = Region_relative frame 0 0 cs cs;
r_tr = fliplr r_tl;
r_bl = fliptb r_tl;
r_br = fliplr r_bl;
r_mt = Region_relative frame ms' 0 ms cs;
r_mb = fliptb r_mt;
r_ml = Region_relative frame 0 ms' cs ms;;
r_mr = fliplr r_ml;
result = build_frame r_tl r_tr r_bl r_br r_mt r_mb r_ml r_mr im_w im_h ov bf;
};
////////////////////////////////////////////////////////////////////////////////
/* Completes the frame building process for simple_frame and corner_frame.
*
* _NG_utilities simple_frame
* _NG_utilities corner_frame
*/
build_frame r_tl r_tr r_bl r_br r_mt r_mb r_ml r_mr im_w im_h ov bf = result
{
//Find pixel thickness of frames section
s_width = r_ml.width - mean (im_profile (map_unary fliplr (r_ml.value)?0) 1);
s_height = r_mt.height - mean (im_profile (map_unary fliptb (r_mt.value)?0) 0);
w_target = im_w + (2 * (s_width - ov));
h_target = im_h + (2 * (s_height - ov));
blend = bf * r_tl.width;
cw_target = w_target - (2 * r_tl.width) + (2 * blend), w_target > (2 * r_tl.width)
= w_target;
ch_target = h_target - (2 * r_tl.height) + (2 * blend), h_target > (2 * r_tl.height)
= h_target;
//Use regions to produce sections
top = merge_to_scale r_mt cw_target blend 0;
bottom = merge_to_scale r_mb cw_target blend 0;
left = merge_to_scale r_ml ch_target blend 1;
right = merge_to_scale r_mr ch_target blend 1;
middle = Image
(image_new cw_target ch_target left.bands left.format left.coding left.type 0 0 0);
//Build sections into full frame.
row_1 = frame_lr_min r_tl r_tr w_target blend, ( w_target < (r_tl.width * 2))
= merge_array blend [[r_tl, top, r_tr]];
row_2 = frame_lr_min left right w_target blend, ( w_target < (r_tl.width * 2))
= merge_array blend [[left, middle, right]];
row_3 = frame_lr_min r_bl r_br w_target blend, ( w_target < (r_tl.width * 2))
= merge_array blend [[r_bl, bottom, r_br]];
result = frame_tb_min row_1 row_3 h_target blend, (h_target < (r_tl.height * 2))
= merge_array blend [[row_1], [row_2], [row_3]];
};
////////////////////////////////////////////////////////////////////////////////
/* Extends or shortens the central sections of a frame, preserving any central details on each
* edge, to fit round a given image.
*
* Called from:
* _NG_Extra.def Frame_item.Complex_frame_item
*/
complex_frame frame im_w im_h ov cs es ms bf option= result
{
cs' = (1 - cs);
ms' = (0.5 - (ms/2));
es' = (0.25 - (es/2));
r_tl = Region_relative frame 0 0 cs cs;
r_tr = fliplr r_tl, option == true
= Region_relative frame cs' 0 cs cs;
r_bl = Region_relative frame 0 cs' cs cs;
r_br = fliplr r_bl, option == true
= Region_relative frame cs' cs' cs cs;
r_mt = Region_relative frame ms' 0 ms cs;
r_mb = Region_relative frame ms' cs' ms cs;
r_ml = Region_relative frame 0 ms' cs ms;
r_mr = fliplr r_ml, option == true
= Region_relative frame cs' ms' cs ms;
r_et = Region_relative frame es' 0 es cs;
r_eb = Region_relative frame es' cs' es cs;
r_el = Region_relative frame 0 es' cs es;
r_er = fliplr r_el, option == true
= Region_relative frame cs' es' cs es;
//Find pixel thickness of frames section
s_width = r_el.width - mean (im_profile (map_unary fliplr (r_el.value)?0) 1);
s_height = r_et.height - mean (im_profile (map_unary fliptb (r_et.value)?0) 0);
w_target = im_w + (2 * (s_width - ov));
h_target = im_h + (2 * (s_height - ov));
min_size = foldr1 min_pair [r_tl.width, r_tl.height,
r_mt.width, r_mt.height,
r_et.width, r_et.height];
blend = bf * min_size;
cw_target = w_target - (2 * r_tl.width) + (2 * blend);
ch_target = h_target - (2 * r_tl.height) + (2 * blend);
top = complex_edge r_mt r_et cw_target blend 0;
bottom = complex_edge r_mb r_eb cw_target blend 0;
left = complex_edge r_ml r_el ch_target blend 1;
right = complex_edge r_mr r_er ch_target blend 1;
middle = Image
(image_new top.width left.height left.bands left.format left.coding left.type 0 0 0);
//Build regions into full frame.
row_1 = frame_lr_min r_tl r_tr w_target blend, ( w_target < (r_tl.width * 2))
= merge_array blend [[r_tl, top, r_tr]];
row_2 = frame_lr_min left right w_target blend, ( w_target < (r_tl.width * 2))
= merge_array blend [[left, middle, right]];
row_3 = frame_lr_min r_bl r_br w_target blend, ( w_target < (r_tl.width * 2))
= merge_array blend [[r_bl, bottom, r_br]];
result = frame_tb_min row_1 row_3 h_target blend, (h_target < (r_tl.height * 2))
= merge_array blend [[row_1], [row_2], [row_3]];
};
////////////////////////////////////////////////////////////////////////////////
/* Function called by complex frame, used to produce section
*
* Called from:
* _NG_utilities.def complex_frame
*/
complex_edge ra rb t bl d = rc
{
e1 = ceil (ra.width - t)/2, d == 0
= 0;
e2 = 0, d == 0
= ceil (ra.height - t)/2;
e3 = t, d == 0
= ra.width;
e4 = ra.height, d == 0
= t;
check = ra.width, d == 0;
= ra.height;
rai = get_image ra;
t2 = (t - ra.width + (2 * bl))/2, d == 0
= (t - ra.height + (2 * bl))/2;
rc = ra , t <= 0
= Image (im_extract_area rai e1 e2 e3 e4), t <= check
= merge_array bl [[rb',ra,rb']], d == 0
= merge_array bl [[rb'],[ra],[rb']]
{rb' = merge_to_scale rb t2 bl d;}
}
//////////////////////////////////////////////////////////////////////////////
/* Blends two images left/right to produce an image a specific width.
*
* _NG_utilities build_frame
* _NG_utilities complex_frame
*/
frame_lr_min r_l r_r target bw = result
{
//Calculating the new widh required for each image.
no = (target/2 + bw);
n_w = no, (r_l.width > no)
= r_l.width;
//Removing excess from what will be the middle of the final image.
n_l = im_extract_area r_l.value 0 0 n_w r_l.height;
n_r = im_extract_area r_r.value (r_r.width - n_w) 0 n_w r_l.height;
//Merge the two image together with a bw*2 pixel overlap.
result = Image (im_lrmerge n_l n_r ((bw*2) - n_w) 0 bw);
};
//////////////////////////////////////////////////////////////////////////////
/* Blends two images top/bottom to produce an image a specific width.
*
* _NG_utilities build_frame
* _NG_utilities complex_frame
*/
frame_tb_min r_t r_b target bw = result
{
//Calculating the new height required for each image.
no = (target/2 + bw);
n_h = no, (r_t.height > no)
= r_t.height;
//Removing excess from what will be the middle of the final image.
n_t = im_extract_area r_t.value 0 0 r_t.width n_h;
n_b = im_extract_area r_b.value 0 (r_b.height - n_h) r_b.width n_h;
//Merge the two image together with a 50 pixel overlap.
result = Image (im_tbmerge n_t n_b 0 ((bw*2) -n_h) bw);
};
//////////////////////////////////////////////////////////////////////////////
/* Resixe canvas of an image to accomodate a frame and possible mount
*
* Called from:
* _NG_Extra.def Frame_item.Frame_corner_item
* _NG_Extra.def Frame_item.Simple_frame_item
* _NG_Extra.def Frame_item.Complex_frame_item
*/
frame_position_image im ref os colour= result
{
background = image_new ref.width ref.height
im.bands im.format im.coding im.type colour 0 0;
result = insert_noexpand xp yp im background
{
xp = (ref.width - im.width)/2;
yp = (ref.height - im.height - os)/2;
}
};
//////////////////////////////////////////////////////////////////////////////
/* Merges an array of images together according to blend width bw
*
* Called from:
* _NG_Utilites.def build_frame
* _NG_Utilites.def complex_frame
* _NG_Utilites.def complex_edge
*/
merge_array bw arr = result
{
merge_lr bw im1 im2 = im3
{
bw' = get_header "Xsize" (get_image im1);
bw'' = -(bw' - bw);
im3 = im_lrmerge (get_image im1) (get_image im2) bw'' 0 bw;
}
merge_tb bw im1 im2 = im3
{
bw' = get_header "Ysize" (get_image im1);
bw'' = -(bw' - bw);
im3 = im_tbmerge (get_image im1) (get_image im2) 0 bw'' bw;
}
im_out = (image_set_origin 0 0 @
foldl1 (merge_tb bw) @
map (foldl1 (merge_lr bw))) arr;
result = Image im_out;
}
//////////////////////////////////////////////////////////////////////////////
/* Repeatably top/bottom add clones of im, with a defined overlap, until final height > target
*
* Called from:
* _NG_Utilites.def build_frame
* _NG_Utilites.def complex_edge
*/
merge_to_scale im target blend dir = result
{
blend' = floor blend;
//allow fir lr or tb process
var_a = im.width, dir == 0
= im.height;
var_w = im.width, dir == 1
= target, target > blend'
= blend';
var_h = im.height, dir == 0
= target, target > blend'
= blend';
//total numner of copies of im requires, taking overlap into account.
no_loops = ceil ((log ((target - blend')/(var_a - blend')))/(log 2));
process im no = result
{
pr_a = get_header "Xsize" (get_image im), dir == 0
= get_header "Ysize" (get_image im);
pr_b = -(pr_a - blend' + 1);
im' = im_lrmerge (get_image im) (get_image im) pr_b 0 blend', dir == 0
= im_tbmerge (get_image im) (get_image im) 0 pr_b blend';
no' = no - 1;
result = im', no' < 1
= process im' no';
}
im_tmp = im.value, var_a > target
= process im no_loops;
result = Image (im_extract_area (get_image im_tmp) 0 0 var_w var_h);
}
//////////////////////////////////////////////////////////////////////////////
/* Selects an elispe based on a line and a width
*
* Called from:
* _NG_Extra.def Select_item.Elipse
*/
select_ellipse line width = mask
{
im = line.image;
//Make a 2 band image whose value equals its coordinates.
im_coor = Image (make_xy im.width im.height);
//Adjust the values to center tham on (line.left, line.top)
im_cent = im_coor - Vector [line.left,line.top];
w = line.width;
h = line.height;
angle = 270, w == 0 && h < 0
= 90, w == 0 && h >= 0
= 360 + atan (h/w), w > 0 && h < 0
= atan (h/w), w > 0 && h >= 0
= 180 + atan (h/w);
a = ( (h ** 2) + (w ** 2) )**0.5;
b = a * width;
x' = ( (cos angle) * im_cent?0) + ( (sin angle) * im_cent?1);
y' = ( (cos angle) * im_cent?1) - ( (sin angle) * im_cent?0);
mask = ( (b**2) * (x'**2) ) + ( (a**2) * (y'**2) ) <= (a * b)**2;
}
//////////////////////////////////////////////////////////////////////////////
/* Selects a tetragon based on four points.
*
* Called from:
* _NG_Extra.def Select_item.Tetragon
* _NG_Extra.def Perspective_item
*/
select_tetragon p1 p2 p3 p4 = mask
{
//Put points in clockwise order starting at the top left.
pt_list = sort_pts_clockwise [p1, p2, p3, p4];
pair_list = [
[ pt_list?0, pt_list?1 ],
[ pt_list?1, pt_list?2 ],
[ pt_list?2, pt_list?3 ],
[ pt_list?3, pt_list?0 ] ];
//Make xy image the same size as p1.image;
im_xy = Image (make_xy p1.image.width p1.image.height);
white = Image (image_new p1.image.width p1.image.height 1 0 Image_coding.NOCODING 1 255 0 0);
mask = foldl process white pair_list;
/* Treat each pair of point as a vector going from p1 to p2,
* then select all to right of line. This is done for each pair,
* the results are all combined to select the area defined by
* the four points.
*/
process im_in pair = im_out
{
x = (pair?0).left;
y = (pair?0).top;
x'= (pair?1).left;
y'= (pair?1).top;
w = x' - x;
h = y' - y;
m = 0, x == x'
= (y-y')/(x-x');
c = 0, x == x'
= ((y*x') - (y'*x))/(x' - x);
mask= im_xy?1 - (im_xy?0 * m) >= c, w > 0
= im_xy?1 - (im_xy?0 * m) <= c, w < 0
= im_xy?0 <= x, w == 0 && h > 0
= im_xy?0 >= x;
im_out = im_in & mask;
}
}
//////////////////////////////////////////////////////////////////////////////
/* Selects a tetragon based on four points.
*
* Called from:
* _NG_Extra.def Select_item.Polygon
*/
select_polygon pt_list = mask
{
group_check = is_Group pt_list;
pt_l = pt_list.value, group_check
= pt_list;
im = (pt_l?0).image;
im_xy = Image (make_xy im.width im.height);
black = Image (image_new im_xy.width im_xy.height 1 0 Image_coding.NOCODING 1 0 0 0);
x = im_xy?0;
y = im_xy?1;
pt_l' = grp_trip pt_l;
mask = foldl process black pt_l';
/*Takes a group adds the first two the end and then creates a lists of
*lists [[a, b, c], [b, c, d] .... [x, a, b]]
*/
grp_trip l = l''
{
px = take 2 l;
l' = join l px;
start = [(take 3 l')];
rest = drop 3 l';
process a b = c
{
x = (last a)?1;
x'= (last a)?2;
x'' = [[x, x', b]];
c = join a x'';
}
l'' = foldl process start rest;
};
process im_in triplet = im_out
{
p1 = triplet?0;
p2 = triplet?1;
p3 = triplet?2;
//check for change in x direction between p1-p2 and p2 -p3
dir_1 = sign (p2.left - p1.left);
dir_2 = sign (p3.left - p2.left);
dir = dir_1 + dir_2;
//define min x limit.
min_x = p1.left, p1.left < p2.left
= p2.left + 1, dir != 0
= p2.left;
//define max x limit.
max_x = p1.left, p1.left > p2.left
= p2.left - 1, dir != 0
= p2.left;
//equation of line defined by p1 and p2
m = line_m p1 p2;
c = line_c p1 p2;
//Every thing below the line
im_test = ((y >= (m * x) + c) & (x >= min_x) & (x <= max_x));
im_out = im_in ^ im_test;
}
line_c p1 p2 = c
{m = line_m p1 p2;
c = p1.top - (m * p1.left);};
line_m p1 p2 = (p2.top - p1.top)/(p2.left - p1.left), p2.left != p1.left
= 0;
}
//////////////////////////////////////////////////////////////////////////////
/* Selects a tetragon based on four points.
*
* Called from:
* _NG_Extra.def Perspective_match_item
* _NG_Extra.def Perspective_item
*/
perspective_transform to from = trans''
{
/*
* Tramsformation matrix is calculated on the bases of the following functions:
* x' = c0x + c1y + c2xy + c3
* y' = c4x + c5y + c6xy + c7
*
* The functions used in vips im_transform works based on the functions:
* x = x' + b0 + b2x' + b4y' + b6x'y'
* y = y' + b1 + b3x' + b5y' + b7x'y'
*
* and is applied in the form of the matrix:
*
* [[b0, b1],
* [b2, b3],
* [b4, b5],
* [b6, b7]]
*
* Therefore our required calculated matrix will be
*
* [[ c3 , c7],
* [(c0 - 1) , c4],
* [ c1 , (c5 - 1)],
* [ c2 , c6]]
*
* to = [x1, y1, x2, y2, x3, y3, x4, y4]
* from = [x1', y1', x2', y2', x3', y3', x4', y4']
* trans = [[c0], [c1], [c2], [c3], [c4], [c5], [c6], [c7]]
*
*/
to' = Matrix
[[to?0, to?1, ((to?0)*(to?1)), 1, 0, 0, 0, 0],
[0, 0, 0, 0, to?0, to?1, ((to?0)*(to?1)), 1],
[to?2, to?3, ((to?2)*(to?3)), 1, 0, 0, 0, 0],
[0, 0, 0, 0, to?2, to?3, ((to?2)*(to?3)), 1],
[to?4, to?5, ((to?4)*(to?5)), 1, 0, 0, 0, 0],
[0, 0, 0, 0, to?4, to?5, ((to?4)*(to?5)), 1],
[to?6, to?7, ((to?6)*(to?7)), 1, 0, 0, 0, 0],
[0, 0, 0, 0, to?6, to?7, ((to?6)*(to?7)), 1]];
from' = Matrix (transpose [from]);
to'' = to' ** (-1);
trans = to'' * from';
trans' = trans.value;
trans''= Matrix [[(trans'?3)?0, (trans'?7)?0 ],
[((trans'?0)?0 - 1), (trans'?4)?0 ],
[(trans'?1)?0, ((trans'?5)?0 - 1)],
[(trans'?2)?0, (trans'?6)?0 ]];
}
//////////////////////////////////////////////////////////////////////////////
/* Sort a list of points into clockwise order.
*
* Called from:
* _NG_utilities.def select_tetragon
* _NG_Extra.def Perspective_match_item
* _NG_Extra.def Perspective_item
*/
sort_pts_clockwise l = l''
{
// sort functions:
f_top a b = a.top < b.top;
f_left a b = a.left < b.left;
f_right a b = a.left > b.left;
l' = sortc f_top l;
l'_a = take 2 l';
l'_b = drop 2 l';
l''_a = sortc f_left l'_a;
l''_b = sortc f_right l'_b;
l'' = join l''_a l''_b;
}
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