get("#137") -- split
get("#349") -- table functions
get("#350") -- RecogUtil 2

function make_sig2letter()
  -- first, signatures from alphabet (#1000080), then additional
  -- signatures for slightly varying instances, e.g. from #1000082
  sigs = "121-1212 1321-12121 121-12121 121-121 1321-1 12-1 12321-12121 1-212 1-1 121-121 121-212 1-1 1-2343 1-232 121-121 121-121 12321-12121 12321-1212 12321-12121 1-1 1-21 12121-56787865 1-21 12321-1 12121-212 132321-12121"
  letters = {"A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "VWX", "Y", "Z",
    "X", "B"}
  
  sigs = split(sigs, " ")
  sig2letter = {}
  
  for i=1, #sigs do
    sig = sigs[i]
    if sig2letter[sig] == nil then sig2letter[sig] = {} end
    table.insert(sig2letter[sig], letters[i])
  end
end

-- [ILT][ILT]N[UY]?RA[ILT]NCANREA[DPOJ] :)

function fix(segidx, letters)
  local w, h = x2-x1, y2-y1
    
  local let = valuestokeys(letters)
  
  local cropped = {
    width = w,
    height = h,
    getInt = function(x, y)
      return img.getInt(x+x1, y+y1)
    end
  }
  
  -- distinguish I and T by width
  if let["I"] and let["T"] then
    local ratio = w/h
    let[ratio >= 0.5 and "I" or "T"] = nil
  end
  
  if let["T"] and let["L"] then
    let[upperToLowerWidth(cropped) < 1 and "T" or "L"] = nil
  end
  
  if let["I"] and let["L"] then
    let[upperToLowerWidth(cropped) <= 0.5 and "I" or "L"] = nil
  end
  
  if let["U"] and let["Y"] then
    local middleY = math.ceil(h/2)
    local middleWidth = getWidth(cropped, middleY)
    --[[local _x2 = getRightmostPoint(cropped, middleY)
    local _x1 = getLeftmostPoint(cropped, middleY)
    print("crop: ", x1, y1, x2, y2)
    print("middleWidth: "..middleWidth..", w: "..w..", middleY: "..middleY..", _x2: ".._x2..", _x1: ".._x1)
    for x=0, cropped.width-1 do
      print(cropped.getInt(x, middleY))
    end]]
    let[middleWidth/w <= 0.5 and "U" or "Y"] = nil
  end

  if let["D"] and let["P"] then
    local upper = upperMaxWidth(cropped)
    local lower = lowerMaxWidth(cropped)
    print("upper", upper, "lower", lower)
    let[upper/lower >= 2 and "D" or "P"] = nil
  end
  
  if let["O"] and let["P"] then
    let[upperMaxWidth(cropped)/lowerMaxWidth(cropped) >= 2 and "O" or "P"] = nil
  end
  
  if let["D"] and let["O"] then
    --local gx, gy = getCenterOfGravity(cropped)
    --print("gx", gx, "w", w)
    --let[gx >= w*0.4 and "D" or "O"] = nil
    local avgLeft = getAverageLeft(cropped)
    print("D/O: avgLeft/w", avgLeft/w)
    let[avgLeft/w >= 0.05 and "D" or "O"] = nil
  end
  
  if (let["D"] or let["O"] or let["P"]) and let["J"] then
    local avgLeft = getAverageLeft(cropped, math.floor(h*0.33), math.floor(h*0.6))
    --print("D/O vs J: avgLeft/w", avgLeft/w)
    if avgLeft/w >= 0.5 then
      let["D"], let["O"], let["P"] = nil, nil, nil
    else
      let["J"] = nil
    end
  end

  if (let["G"] or let["S"]) and let["Q"] then
    local yo, threshold = 8/9, 0.4
    local yy = math.floor(h*yo)
    local avgLeft = getAverageLeft(cropped, yy, h)
    print("G vs Q: avgLeft/w", avgLeft/w, "h", h, "yo", yo, "yy", yy)
    if avgLeft/w >= threshold then
      let["G"], let["S"] = nil, nil
    else
      let["Q"] = nil
    end
  end
  
  if let["G"] and let["S"] then
    local middleY = math.floor(h/2)
    local left = getLeftmostPoint(cropped, middleY)/w
    print("G vs S: left", left)
    let[left >= 0.15 and "G" or "S"] = nil
  end
  
  letters = keystolist(let)
  return letters
end

-- works on x1, lastX2
function isSpace()
  if lastX2 == nil then return false end
  local d = (x1-lastX2)/(y2-y1)
  --print("space dist", d)
  return d >= 0.3
end

make_sig2letter()

result = otherresults["#345"] or error("Need result of #345")
_, _, s = string.find(result, ": (.+)")
if s == nil then return end
parts = split(s, "|")

-- could also recalc this from parts
sigs = otherresults["#340"] or error("Need result of #340")
sigs = split(sigs, " ")

result = {}

for i=1, #sigs do
  sig = sigs[i]
  letters = sig2letter[sig]
  part = parts[i]
  lastX2 = x2
  x1, y1, x2, y2 = unpack(split(part, ", "))
  x1, y1, x2, y2 = tonumber(x1), tonumber(y1), tonumber(x2), tonumber(y2)
  if isSpace() then table.insert(result, " ") end
    
  s = ""
  if letters == nil then
    print("Unknown signature: "..sig)
    s = "?"
  else
    if #letters > 1 then
      letters = fix(i, letters)
    end
    if #letters == 1 then
      s = letters[1]
    else
      s = "["..table.concat(letters, "").."]"
    end
  end
  table.insert(result, s)
end

return table.concat(result, "")

Improved version of #344