Depth Of Field Info script Chdk version

DOFIC.lua

--[[
@DOFIC
Rev 0.835
Garry George
@chdk_version 1.5
# show_DOFIC = 1 "Display DOFIC?" {No Yes}
# show_coc = 0 "Show Inf focus blurs?" {No Yes}
# time_2_show = 5 "Display timeout (s)" [3 30]
# pos = 1 "Vertical position" [0 14]
--]]

require('rawoplib')

set_config_value(2270,"Always")
set_config_value(2271,time_2_show)
set_config_value(2270,1)
set_config_value(2151,0)
set_config_value(2152,0)

function restore()
    set_console_layout(0,0,45,14)
end

infinity = 999999 -- an acceptably large number that CHDK can handle and that is beyond Canon reporting
dof = get_dofinfo()
coc = dof.coc -- CHDK infinity blur (um) at the hyperfocal, ie the defocus Circle of Confusion, which the script uses as the overlap criterion
N, xx, x, ndof, fdof, f, last_x, last_fdof, last_ndof, last_f, last_N = 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
last_step_x, last_step_f, last_step_N = 0, 0, 0
ecnt = get_exp_count()
no_image = true
min = coc*36000/(15*rawop.get_jpeg_width()) -- estimate of 2 sensor pixels infinity focusing limit

function something_changed()
    dof = get_dofinfo()
    N = dof.aperture
    f = dof.focal_length/1000 -- within a mm of the actual focal length, ie good enough
    x = dof.focus -- CHDK estimate of focus 'from the lens'
    ndof = dof.near -- note these are the defocus alone dofs, based on the CHDK CoC. That is no diffraction
    fdof = dof.far
    H = dof.hyp_dist

    if x ~= last_step_x or f ~= last_step_f or N ~= last_step_N then 
        return true 
    else 
        return false 
    end
end

function update_info()
    repeat sleep(10) until not get_shooting() -- make sure any capture taking place is completed
    if ecnt ~= get_exp_count() then -- register captured image's focus info
        last_ndof = ndof
        last_fdof = fdof
        last_x = x
        last_f = f
        last_N = N
        last_step_N = -N -- to force a console refresh
        ecnt = get_exp_count()
        no_image = false
    end

    if (x < 0) then -- at infinity, so correct CHDK value for use by the script
        ndof = H/2 -- note CHDK erroneously reports ndof, when focused at infinity, as infinity, ie -1
        x = infinity  -- as CHDK reports infinity as -1, so can't use it directly
    end

    if (fdof == -1) then fdof = infinity end

    if (x == infinity) or (x > H) then
        num = 0
    else
        num = (1 + (H/x))/2 -- estimate of number of focus brackets from current focus to H
    end

    -- Because we are using integer math Lua, we need to muck about a bit :-(
    scale = imath.scale
    diff_b = imath.mul(1342,N) -- diffraction blur diameter = 2.44*0.550*N = 1'342*N (at vis bands, ie change for IR converted cam)
    inf_b = scale*coc -- infinity defocus blur, scaled from H definded blur, ie CHDK coc, around 30um/crop. Consider switching on show_coc, as this reminds you what the 'just acceptable' defocus blur is
    temp = imath.div(scale*H,scale*x)
    inf_b = imath.mul(inf_b,temp)

    if x == infinity then
        inf_b = 0
        tot_b = diff_b
    else
        tot_b = imath.mul(inf_b,inf_b) + imath.mul(diff_b,diff_b)
        if tot_b < 16384000 then 
            tot_b = imath.sqrt(tot_b)
        else
            tot_b = inf_b
        end
    end

    tot_b = imath.round(tot_b)/scale -- all blurs now converted to um
    inf_b = imath.round(inf_b)/scale
    diff_b = imath.round(diff_b)/scale

    info = inf_b.."/"..diff_b.."/"..tot_b
    if tot_b == inf_b then info = tot_b end
    
    if x == infinity then
        info = "oo: "..info
    elseif (x < H) then
        info = num.."<H: "..info
    else
        info = ">H: "..info
    end

    if no_image then
        info = info.." [X]"
    elseif x == last_x then
        info = info.." [=]"
    elseif ((fdof >= last_ndof) and (fdof <= last_fdof)) or ((ndof <= last_fdof) and (fdof >= last_fdof)) then
        info = info.." [+]"
    elseif (fdof < last_ndof) or (ndof > last_fdof) then
        info = info.." [-]"
    end

    ls = info:len() -- character length of string

    if show_coc == 1 then 
        info = " ["..coc..":"..min.."] "..info.." "
    else
        info = " "..info.." "
    end
    ls = info:len()
    set_console_layout(0,pos,ls,pos+1)
    
end

-- Run in the background, in non Alt mode

exit_alt()

while show_DOFIC == 1 do 
    if  something_changed() or is_pressed("shoot_half") then -- update console
        update_info() 
        print(info)
        last_step_N = N
        last_step_x = x
        last_step_f = f
    end
    sleep(100) -- free to adjust
end