From 91758b61c3bf988578df38f6186084cf9404d10b Mon Sep 17 00:00:00 2001
From: khampf <k.hampf.net@gmail.com>
Date: Fri, 21 Apr 2017 13:51:40 +0300
Subject: [PATCH] ISO 19794-5/ICAO 9303 clipping guide as
 contrib/passport_guide.lua

---
 contrib/passport_guide.lua | 73 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 contrib/passport_guide.lua

diff --git a/contrib/passport_guide.lua b/contrib/passport_guide.lua
new file mode 100644
index 0000000..0e894f2
--- /dev/null
+++ b/contrib/passport_guide.lua
@@ -0,0 +1,73 @@
+--[[
+PASSPORT CROPPING GUIDE
+guides for cropping passport photos based on documents from the Finnish police
+(https://www.poliisi.fi/instancedata/prime_product_julkaisu/intermin/embeds/poliisiwwwstructure/38462_Passikuvaohje_EN.pdf) describing passport photo dimensions of 47x36 mm and 500x653 px for digital biometric data stored in passports. They use ISO 19794-5 standard based on ICAO 9303 regulations which should also be compliant for all of Europe.
+
+AUTHOR
+Kåre Hampf (k.hampf@gmail.com)
+
+INSTALLATION
+* copy this file in $CONFIGDIR/lua/ where CONFIGDIR is your darktable configuration directory
+* add the following line in the file $CONFIGDIR/luarc
+  require "passport_guide"
+* (optional) add the line:
+  "plugins/darkroom/clipping/extra_aspect_ratios/passport 36x47mm=47:36"
+  to $CONFIGDIR/darktablerc
+
+USAGE
+* when using the cropping tool, select "passport" as guide and if you added the line in yout rc
+  select "passport 36x47mm" as aspect
+
+LICENSE
+GPLv2
+
+]]
+
+local dt = require "darktable"
+dt.configuration.check_version(...,{2,0,0},{3,0,0},{4,0,0})
+
+dt.guides.register_guide("passport",
+-- draw
+function(cr, x, y, w, h, zoom_scale)
+  local _w, _h
+
+  -- get the max 36x47 rectangle
+  local aspect_ratio = 47 / 36
+  if w * aspect_ratio > h then
+    _w = h / aspect_ratio
+    _h = h
+  else
+    _w = w
+    _h = w * aspect_ratio
+  end
+
+  cr:save()
+
+  cr:translate(x + (w - _w) / 2, y + (h - _h) / 2)
+  cr:scale(_w / 36, _h / 47)
+
+  -- the outer rectangle
+  cr:rectangle( 0, 0, 36, 47)
+
+  -- vertical bars
+  cr:draw_line(16.5, 8, 16.5, 36)
+  cr:draw_line(19.5, 8, 19.5, 36)
+
+  -- long horisontal bars
+  cr:draw_line(6, 4, 30, 4)
+  cr:draw_line(6, 40, 30, 40)
+
+  -- short horisontal bars
+  cr:draw_line(9, 6, 27, 6)
+  cr:draw_line(9, 38, 27, 38)
+
+  cr:restore()
+end,
+-- gui
+function()
+  return dt.new_widget("label"){label = "ISO 19794-5/ICAO 9309 passport", halign = "start"}
+end
+)
+
+-- kate: tab-indents: off; indent-width 2; replace-tabs on; remove-trailing-space on; hl Lua;
+-- vim: shiftwidth=2 expandtab tabstop=2 cindent syntax=lua