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%
% A few arrays used to adjust reference points and character widths in some
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% Move braceleftbt a bit - default PostScript character is off a bit.
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	/bracketrightex		[220 -125 500 0]
	/radical		[0 0 550 0]
	/radicalex		[-50 0 500 0]
	/parenleftex		[-20 -170 0 0]
	/integral		[100 -50 500 0]
	/infinity		[10 -75 730 0]
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/S1defs [
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	/endash			[7 90 650 0]
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%
% Tries to round clipping path dimensions, as stored in array pagebbox, so they
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%%EndProlog
%%BeginSetup
mark
%
% Encoding vector and redefinition of findfont for the ISO Latin1 standard.
% The 18 characters missing from ROM based fonts on older printers are noted
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%

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/NewFontDirectory FontDirectory maxlength dict def

%
% Apparently no guarantee findfont is defined in systemdict so the obvious
%
%	systemdict /findfont get exec
%
% can generate an error. So far the only exception is a VT600 (version 48.0).
%

userdict /@RealFindfont known not {
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} if

/findfont {
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setup
%%EndSetup
%%Page: 1 1
/saveobj save def
mark
1 pagesetup
12 /Times-Bold f
(Pnmconvol) 2243 1230 w
(User) 2847 1230 w
(Manual) 3116 1230 w
10 /Times-Bold f
(pnmconvol) 720 1920 w
10 /Times-Roman f
(Updated: 29 June 2005) 720 2076 w
(Table Of Contents) 720 2196 w
10 /Times-Bold f
(NAME) 720 2436 w
10 /Times-Roman f
(pnmconvol \255 general MxN convolution on a PNM image) 720 2592 w
10 /Times-Bold f
(SYNOPSIS) 720 2832 w
(pnmconvol) 720 2988 w
10 /Times-Italic f
(convolution) 1218 2988 w
10 /S f
(_) 1690 2988 w
10 /Times-Italic f
(matrix) 1740 2988 w
10 /S f
(_) 2001 2988 w
10 /Times-Italic f
(file) 2051 2988 w
10 /Times-Roman f
([\255nooffset] [) 2204 2988 w
10 /Times-Italic f
(pnmfile) 2688 2988 w
10 /Times-Roman f
(]) 2988 2988 w
(Minimum) 720 3144 w
(unique) 1162 3144 w
(abbreviation) 1475 3144 w
(of) 2015 3144 w
(option) 2140 3144 w
(is) 2438 3144 w
(acceptable.) 2547 3144 w
(You) 3059 3144 w
(may) 3273 3144 w
(use) 3487 3144 w
(double) 3662 3144 w
(hyphens) 3976 3144 w
(instead) 4351 3144 w
(of) 4676 3144 w
(single) 4801 3144 w
(hyphen) 720 3264 w
(to) 1042 3264 w
(denote) 1148 3264 w
(options.) 1442 3264 w
(You) 1815 3264 w
(may) 2015 3264 w
(use) 2215 3264 w
(white) 2376 3264 w
(space) 2626 3264 w
(in) 2875 3264 w
(place) 2981 3264 w
(of) 3219 3264 w
(the) 3330 3264 w
(equals) 3480 3264 w
(sign) 3763 3264 w
(to) 3958 3264 w
(separate) 4064 3264 w
(an) 4418 3264 w
(option) 4540 3264 w
(name) 4824 3264 w
(from its value.) 720 3384 w
10 /Times-Bold f
(DESCRIPTION) 720 3624 w
10 /Times-Roman f
(This program is part of Netpbm.) 720 3816 w
10 /Times-Bold f
(pnmconvol) 720 3972 w
10 /Times-Roman f
(reads) 1219 3972 w
(two) 1455 3972 w
(PNM) 1631 3972 w
(images) 1874 3972 w
(as) 2183 3972 w
(input,) 2292 3972 w
(convolves) 2549 3972 w
(the) 2980 3972 w
(second) 3129 3972 w
(using) 3433 3972 w
(the) 3677 3972 w
(first,) 3826 3972 w
(and) 4039 3972 w
(writes) 4210 3972 w
(a) 4481 3972 w
(PNM) 4552 3972 w
(image) 4796 3972 w
(as output.) 720 4092 w
(Convolution) 720 4248 w
(means) 1247 4248 w
(replacing) 1528 4248 w
(each) 1925 4248 w
(pixel) 2133 4248 w
(with) 2359 4248 w
(a) 2563 4248 w
(weighted) 2633 4248 w
(average) 3025 4248 w
(of) 3360 4248 w
(the) 3469 4248 w
(nearby) 3617 4248 w
(pixels.) 3914 4248 w
(The) 4229 4248 w
(weights) 4410 4248 w
(and) 4747 4248 w
(the) 4918 4248 w
(area) 720 4368 w
(to) 919 4368 w
(average) 1031 4368 w
(are) 1374 4368 w
(determined) 1528 4368 w
(by) 2010 4368 w
(the) 2143 4368 w
(convolution) 2298 4368 w
(matrix) 2809 4368 w
(\(sometimes) 3103 4368 w
(called) 3597 4368 w
(a) 3868 4368 w
(convolution) 3945 4368 w
(kernel\),) 4456 4368 w
(which) 4796 4368 w
(you) 720 4488 w
(supply) 902 4488 w
(by) 1201 4488 w
(way) 1333 4488 w
(of) 1531 4488 w
(the) 1646 4488 w
(PNM) 1800 4488 w
(image) 2049 4488 w
(in) 2325 4488 w
(the) 2435 4488 w
(file) 2589 4488 w
(you) 2754 4488 w
(identify) 2936 4488 w
(with) 3279 4488 w
(the) 3489 4488 w
10 /Times-Italic f
(convolution) 3644 4488 w
10 /S f
(_) 4116 4488 w
10 /Times-Italic f
(matrix) 4166 4488 w
10 /S f
(_) 4427 4488 w
10 /Times-Italic f
(file) 4477 4488 w
10 /Times-Roman f
(argument.) 4638 4488 w
(There) 720 4608 w
(are) 983 4608 w
(two) 1135 4608 w
(ways) 1315 4608 w
10 /Times-Bold f
(pnmconvol) 1550 4608 w
10 /Times-Roman f
(interprets) 2053 4608 w
(the) 2460 4608 w
(PNM) 2612 4608 w
(convolution) 2859 4608 w
(matrix) 3367 4608 w
(image) 3658 4608 w
(pixels) 3932 4608 w
(as) 4201 4608 w
(weights:) 4314 4608 w
(with) 4683 4608 w
(off\255) 4891 4608 w
(sets, and without offsets.) 720 4728 w
(The) 720 4884 w
(simpler) 903 4884 w
(of) 1231 4884 w
(the) 1342 4884 w
(two) 1492 4884 w
(is) 1670 4884 w
(without) 1765 4884 w
(offsets.) 2099 4884 w
(That) 2443 4884 w
(is) 2655 4884 w
(what) 2751 4884 w
(happens) 2974 4884 w
(when) 3330 4884 w
(you) 3575 4884 w
(specify) 3754 4884 w
(the) 4071 4884 w
10 /Times-Bold f
(\255nooffset) 4222 4884 w
10 /Times-Roman f
(option.) 4622 4884 w
(In) 4957 4884 w
(that case,) 720 5004 w
10 /Times-Bold f
(pnmconvol) 1116 5004 w
10 /Times-Roman f
(simply normalizes the sample values in the PNM image by dividing by the maxval.) 1614 5004 w
(For) 720 5160 w
(example,) 886 5160 w
(here) 1276 5160 w
(is) 1474 5160 w
(a) 1568 5160 w
(sample) 1639 5160 w
(convolution) 1949 5160 w
(file) 2454 5160 w
(that) 2614 5160 w
(causes) 2792 5160 w
(an) 3080 5160 w
(output) 3202 5160 w
(pixel) 3486 5160 w
(to) 3714 5160 w
(be) 3820 5160 w
(a) 3942 5160 w
(simple) 4014 5160 w
(average) 4309 5160 w
(of) 4646 5160 w
(its) 4757 5160 w
(cor\255) 4880 5160 w
(responding input pixel and its 8 neighbors, resulting in a smoothed image:) 720 5280 w
(P2) 820 5460 w
(3 3) 820 5580 w
(18) 820 5700 w
(2 2 2) 820 5820 w
(2 2 2) 820 5940 w
(2 2 2) 820 6060 w
(\(Note) 720 6276 w
(that) 978 6276 w
(the) 1159 6276 w
(above) 1312 6276 w
(text) 1581 6276 w
(is) 1762 6276 w
(an) 1860 6276 w
(actual) 1985 6276 w
(PGM) 2254 6276 w
(file) 2502 6276 w
(\255\255) 2666 6276 w
(you) 2763 6276 w
(can) 2944 6276 w
(cut) 3113 6276 w
(and) 3266 6276 w
(paste) 3441 6276 w
(it.) 3677 6276 w
(If) 3814 6276 w
(you're) 3911 6276 w
(not) 4202 6276 w
(familiar) 4361 6276 w
(with) 4708 6276 w
(the) 4918 6276 w
(plain PGM format, see the PGM format specification\).) 720 6396 w
10 /Times-Bold f
(pnmconvol) 720 6552 w
10 /Times-Roman f
(divides) 1224 6552 w
(each) 1544 6552 w
(of) 1757 6552 w
(the) 1871 6552 w
(sample) 2024 6552 w
(values) 2338 6552 w
(\(2\)) 2624 6552 w
(by) 2771 6552 w
(the) 2902 6552 w
(maxval) 3055 6552 w
(\(18\)) 3380 6552 w
(so) 3577 6552 w
(the) 3697 6552 w
(weight) 3850 6552 w
(of) 4154 6552 w
(each) 4269 6552 w
(of) 4483 6552 w
(the) 4598 6552 w
(9) 4752 6552 w
(input) 4834 6552 w
(pixels) 720 6672 w
(gets) 996 6672 w
(is) 1194 6672 w
(1/9,) 1297 6672 w
(which) 1486 6672 w
(is) 1766 6672 w
(exactly) 1869 6672 w
(what) 2193 6672 w
(you) 2423 6672 w
(want) 2609 6672 w
(to) 2839 6672 w
(keep) 2953 6672 w
(the) 3177 6672 w
(overall) 3335 6672 w
(brightness) 3648 6672 w
(of) 4095 6672 w
(the) 4214 6672 w
(image) 4372 6672 w
(the) 4652 6672 w
(same.) 4810 6672 w
10 /Times-Bold f
(pnmconvol) 720 6792 w
10 /Times-Roman f
(creates an output pixel by multiplying the values of each of 9 pixels by 1/9 and adding.) 1218 6792 w
(Note that with maxval 18, the range of possible values is 0 to 18.) 720 6948 w
(After scaling, the range is 0 to 1.) 3365 6948 w
(For) 720 7104 w
(a) 900 7104 w
(normal) 985 7104 w
(convolution,) 1309 7104 w
(where) 1853 7104 w
(you're) 2137 7104 w
(neither) 2438 7104 w
(adding) 2756 7104 w
(nor) 3069 7104 w
(subtracting) 3243 7104 w
(total) 3728 7104 w
(value) 3947 7104 w
(from) 4204 7104 w
(the) 4439 7104 w
(image,) 4602 7104 w
(but) 4912 7104 w
(merely) 720 7224 w
(moving) 1042 7224 w
(it) 1393 7224 w
(around,) 1494 7224 w
(you'll) 1841 7224 w
(want) 2125 7224 w
(to) 2364 7224 w
(make) 2487 7224 w
(sure) 2748 7224 w
(that) 2959 7224 w
(all) 3154 7224 w
(the) 3298 7224 w
(scaled) 3464 7224 w
(values) 3757 7224 w
(in) 4056 7224 w
(\(each) 4178 7224 w
(plane) 4437 7224 w
(of\)) 4697 7224 w
(your) 4857 7224 w
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showpage
saveobj restore
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/saveobj save def
mark
2 pagesetup
10 /Times-Roman f
(\255 2 \255) 2797 480 w
(convolution PNM add up to 1, which means all the actual sample values add up to the maxval.) 720 840 w
(When) 720 996 w
(you) 991 996 w
(don't) 1174 996 w
(specify) 1418 996 w
10 /Times-Bold f
(\255nooffset) 1740 996 w
10 /Times-Roman f
(,) 2111 996 w
10 /Times-Bold f
(pnmconvol) 2170 996 w
10 /Times-Roman f
(applies) 2677 996 w
(an) 2994 996 w
(offset,) 3122 996 w
(the) 3408 996 w
(purpose) 3564 996 w
(of) 3914 996 w
(which) 4031 996 w
(is) 4309 996 w
(to) 4410 996 w
(allow) 4522 996 w
(you) 4778 996 w
(to) 4962 996 w
(indicate) 720 1116 w
(negative) 1073 1116 w
(weights) 1448 1116 w
(even) 1796 1116 w
(though) 2020 1116 w
(PNM) 2334 1116 w
(sample) 2587 1116 w
(values) 2906 1116 w
(are) 3197 1116 w
(never) 3354 1116 w
(negative.) 3611 1116 w
(In) 4035 1116 w
(this) 4154 1116 w
(case,) 4335 1116 w
10 /Times-Bold f
(pnmconvol) 4567 1116 w
10 /Times-Roman f
(subtracts) 720 1236 w
(half) 1103 1236 w
(the) 1286 1236 w
(maxval) 1437 1236 w
(from) 1760 1236 w
(each) 1983 1236 w
(sample) 2194 1236 w
(and) 2506 1236 w
(then) 2679 1236 w
(normalizes) 2880 1236 w
(by) 3347 1236 w
(dividing) 3476 1236 w
(by) 3839 1236 w
(half) 3968 1236 w
(the) 4152 1236 w
(maxval.) 4303 1236 w
(So) 4676 1236 w
(to) 4811 1236 w
(get) 4918 1236 w
(the) 720 1356 w
(same) 868 1356 w
(result) 1099 1356 w
(as) 1347 1356 w
(we) 1456 1356 w
(did) 1598 1356 w
(above) 1752 1356 w
(with) 2016 1356 w
10 /Times-Bold f
(\255nooffset) 2220 1356 w
10 /Times-Roman f
(,) 2591 1356 w
(the) 2642 1356 w
(convolution) 2790 1356 w
(matrix) 3294 1356 w
(PNM) 3581 1356 w
(image) 3824 1356 w
(would) 4094 1356 w
(have) 4370 1356 w
(to look like) 4584 1356 w
(this:) 720 1476 w
(P2) 820 1656 w
(3 3) 820 1776 w
(18) 820 1896 w
(10 10 10) 820 2016 w
(10 10 10) 820 2136 w
(10 10 10) 820 2256 w
(To) 720 2472 w
(see) 863 2472 w
(how) 1022 2472 w
(this) 1226 2472 w
(works,) 1403 2472 w
(do) 1704 2472 w
(the) 1836 2472 w
(above\255mentioned) 1990 2472 w
(offset:) 2715 2472 w
(10) 3002 2472 w
(\255) 3134 2472 w
(18/2) 3199 2472 w
(gives) 3409 2472 w
(1.) 3652 2472 w
(The) 3784 2472 w
(normalization) 3971 2472 w
(step) 4558 2472 w
(divides) 4751 2472 w
(by) 720 2592 w
(18/2) 849 2592 w
(=) 1056 2592 w
(9,) 1141 2592 w
(which) 1245 2592 w
(makes) 1518 2592 w
(it) 1802 2592 w
(1/9) 1887 2592 w
(\255) 2044 2592 w
(exactly) 2106 2592 w
(what) 2423 2592 w
(you) 2646 2592 w
(want.) 2825 2592 w
(The) 3098 2592 w
(equivalent) 3282 2592 w
(matrix) 3727 2592 w
(for) 4017 2592 w
(5x5) 4161 2592 w
(smoothing) 4339 2592 w
(would) 4790 2592 w
(have maxval 50 and be filled with 26.) 720 2712 w
(Note) 720 2868 w
(that) 941 2868 w
(with) 1118 2868 w
(maxval) 1323 2868 w
(18,) 1645 2868 w
(the) 1798 2868 w
(range) 1948 2868 w
(of) 2197 2868 w
(possible) 2308 2868 w
(values) 2664 2868 w
(is) 2947 2868 w
(0) 3042 2868 w
(to) 3120 2868 w
(18.) 3226 2868 w
(After) 3404 2868 w
(offset,) 3642 2868 w
(that's) 3922 2868 w
(\2559) 4172 2868 w
(to) 4283 2868 w
(9,) 4389 2868 w
(and) 4492 2868 w
(after) 4664 2868 w
(nor\255) 4874 2868 w
(malizing, the range is \2551 to 1.) 720 2988 w
(For) 720 3144 w
(a) 900 3144 w
(normal) 985 3144 w
(convolution,) 1309 3144 w
(where) 1853 3144 w
(you're) 2137 3144 w
(neither) 2438 3144 w
(adding) 2756 3144 w
(nor) 3069 3144 w
(subtracting) 3243 3144 w
(total) 3728 3144 w
(value) 3947 3144 w
(from) 4204 3144 w
(the) 4439 3144 w
(image,) 4602 3144 w
(but) 4912 3144 w
(merely) 720 3264 w
(moving) 1026 3264 w
(it) 1361 3264 w
(around,) 1446 3264 w
(you'll) 1777 3264 w
(want) 2045 3264 w
(to) 2268 3264 w
(make) 2375 3264 w
(sure) 2620 3264 w
(that) 2815 3264 w
(all) 2994 3264 w
(the) 3123 3264 w
(offset,) 3274 3264 w
(scaled) 3555 3264 w
(values) 3833 3264 w
(in) 4117 3264 w
(\(each) 4224 3264 w
(plane) 4468 3264 w
(of\)) 4713 3264 w
(your) 4857 3264 w
(convolution) 720 3384 w
(PNM) 1230 3384 w
(add) 1479 3384 w
(up) 1655 3384 w
(to) 1787 3384 w
(1.) 1897 3384 w
(That) 2029 3384 w
(means) 2244 3384 w
(the) 2531 3384 w
(actual) 2686 3384 w
(sample) 2957 3384 w
(values,) 3273 3384 w
(less) 3586 3384 w
(half) 3769 3384 w
(the) 3957 3384 w
(maxval,) 4112 3384 w
(add) 4464 3384 w
(up) 4641 3384 w
(to) 4774 3384 w
(half) 4885 3384 w
(the maxval as in the example above.) 720 3504 w
(The convolution file will usually be a PGM, so) 720 3660 w
(that) 2626 3660 w
(the) 2802 3660 w
(same) 2950 3660 w
(convolution) 3181 3660 w
(gets) 3685 3660 w
(applied) 3872 3660 w
(to) 4192 3660 w
(each) 4296 3660 w
(color) 4504 3660 w
(compo\255) 4735 3660 w
(nent.) 720 3780 w
(However,) 974 3780 w
(if) 1396 3780 w
(you) 1489 3780 w
(want) 1671 3780 w
(to) 1897 3780 w
(use) 2007 3780 w
(a) 2172 3780 w
(PPM) 2248 3780 w
(and) 2481 3780 w
(do) 2657 3780 w
(a) 2789 3780 w
(different) 2865 3780 w
(convolution) 3240 3780 w
(to) 3750 3780 w
(different) 3860 3780 w
(colors,) 4235 3780 w
(you) 4536 3780 w
(can) 4717 3780 w
(cer\255) 4886 3780 w
(tainly do that.) 720 3900 w
(At) 720 4056 w
(the) 859 4056 w
(edges) 1020 4056 w
(of) 1286 4056 w
(the) 1408 4056 w
(convolved) 1569 4056 w
(image,) 2024 4056 w
(where) 2332 4056 w
(the) 2614 4056 w
(convolution) 2775 4056 w
(matrix) 3292 4056 w
(would) 3592 4056 w
(extend) 3882 4056 w
(over) 4188 4056 w
(the) 4405 4056 w
(edge) 4567 4056 w
(of) 4795 4056 w
(the) 4918 4056 w
(image,) 720 4176 w
10 /Times-Bold f
(pnmconvol) 1014 4176 w
10 /Times-Roman f
(just copies the input pixels directly to the output.) 1512 4176 w
(The) 720 4332 w
(convolution) 908 4332 w
(computation) 1419 4332 w
(can) 1952 4332 w
(result) 2123 4332 w
(in) 2378 4332 w
(a) 2489 4332 w
(value) 2566 4332 w
(which) 2815 4332 w
(is) 3092 4332 w
(outside) 3192 4332 w
(the) 3515 4332 w
(range) 3671 4332 w
(representable) 3926 4332 w
(in) 4491 4332 w
(the) 4603 4332 w
(output.) 4759 4332 w
(When that happens,) 720 4452 w
10 /Times-Bold f
(pnmconvol) 1535 4452 w
10 /Times-Roman f
(just clips the output, which means brightness is not conserved.) 2033 4452 w
10 /Times-Bold f
(HISTORY) 720 4692 w
10 /Times-Roman f
(The) 720 4884 w
10 /Times-Bold f
(\255nooffset) 900 4884 w
10 /Times-Roman f
(option was new in Netpbm 10.23 \(July 2004\).) 1296 4884 w
10 /Times-Bold f
(SEE ALSO) 720 5124 w
(pnmsmooth) 720 5280 w
10 /Times-Roman f
(,) 1226 5280 w
10 /Times-Bold f
(pgmmorphconv) 1276 5280 w
10 /Times-Roman f
(,) 1954 5280 w
10 /Times-Bold f
(pnmnlfilt) 2004 5280 w
10 /Times-Roman f
(,) 2405 5280 w
10 /Times-Bold f
(pgmkernel) 2455 5280 w
10 /Times-Roman f
(,) 2916 5280 w
10 /Times-Bold f
(pamgauss) 2966 5280 w
10 /Times-Roman f
(,) 3389 5280 w
10 /Times-Bold f
(pnm) 3439 5280 w
(AUTHORS) 720 5520 w
10 /Times-Roman f
(Copyright \(C\) 1989, 1991 by Jef Poskanzer.) 720 5676 w
(Modified 26 November 1994 by Mike Burns, burns@chem.psu.edu) 720 5796 w
10 /S1 f
(________________________________________________________________________) 720 5916 w
10 /Times-Bold f
(Table Of Contents) 720 6156 w
10 /LucidaSansUnicode22 f
(\031) 720 6348 w
10 /Times-Roman f
(NAME) 970 6348 w
10 /LucidaSansUnicode22 f
(\031) 720 6504 w
10 /Times-Roman f
(SYNOPSIS) 970 6504 w
10 /LucidaSansUnicode22 f
(\031) 720 6660 w
10 /Times-Roman f
(DESCRIPTION) 970 6660 w
10 /LucidaSansUnicode22 f
(\031) 720 6816 w
10 /Times-Roman f
(SEE ALSO) 970 6816 w
10 /LucidaSansUnicode22 f
(\031) 720 6972 w
10 /Times-Roman f
(HISTORY) 970 6972 w
10 /LucidaSansUnicode22 f
(\031) 720 7128 w
10 /Times-Roman f
(AUTHORS) 970 7128 w
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