!752

static Map<BWImage, S> chars;

!include #1000522 // helper functions

static int luaMaxSteps = 100*1000*1000;

sS code = [[

  -- Input:

  --   iw = image of word to recognize

  --   chars = images of characters & description

  -- Output:

  --   what is recognized (a string)

  local threshold = 0.95

  -- main algorithm

  local buf = {}

  for x=0, iw.w-1 do

    local best, bestChar, bestCharImg = 0, nil, nil

    for ic, c in pairs(chars) do

      local score = roughMatch(ic, iw, x)

      if score > best then

        bestChar = c

        bestCharImg = ic

        best = score

      end

    end

    if bestChar ~= nil and best > threshold then

      table.insert(buf, bestChar)

      x = x + bestCharImg.w-2

    end

  end

  return table.concat(buf)

  -- done

]];

static bool prepareNext() {

  L<S> lines = toLines(code);

  S txt = "local threshold = ";

  int i = indexOfElementThatContains(lines, txt);

  if (i < 0) false;

  lines.set(i, print("    " + txt + formatDouble(random(0.96, 1.0), 8)));

  code = fromLines(lines);

  //printCode();

  ret true;

}

static void printCode() {

  print(code); // to do: with line numbers

}

static S getParams() {

  ret structure(litmap("code", code));

}

static S recognizeWord(BWImage iw, O infos) {

  chars = (Map) quickImport(get(infos, "chars"));

  luaMaxSteps(luaMaxSteps);

  ret evalLua(makeSandbox(iw), code).tojstring();

}

static Sandbox makeSandbox(final BWImage img) {

  new LuaTable lChars;

  int i = 0;

  for (BWImage ic : keys(chars))

    lChars.set(bwImageToLua(ic), Lua.value(chars.get(ic)));

  ret luaSandbox(

    "iw", bwImageToLua(img),

    "chars", lChars,

    "roughMatch", new ThreeArgFunction {

      public LuaValue call(LuaValue ic, LuaValue iw, LuaValue x1) {

        BWImage _ic = bwImageFromLua(ic);

        BWImage _iw = bwImageFromLua(iw);

        // TODO: optimize

        ret LuaValue.valueOf(

          1-diff(_ic, _iw.clip(x1.toint(), 0, _ic.getWidth(), _ic.getHeight())));

      }

    });

}