deblink_lib.avs

LoadPlugin("mvtools2.dll")
LoadPlugin("mt_masktools-26.dll")

function ng_deblink(clip clp,
\ float "ratio",
\ int "level",
\ clip "blinkmask"
\){
#Version 10 2012.04.22

    blink = default(blinkmask, clp.ng_blinkmask())

    ratio = default(ratio, 2.0 /3)
    assert(ratio >= 0.0 && 1.0 >= ratio,
    \      "[ng_deblink] 1.0 >= ratio >= 0.0, it was " + string(ratio))

    level = default(level, round(ratio * 257))
    assert(level >= 0 && 257 >= level,
    \      "[ng_deblink] 257 >= level >= 0, it was " + string(level))

    m01=mt_logic(blink.SelectEvery(4,0),
\                blink.SelectEvery(4,1),
\                mode="or").ConvertToRGB32()
    m23=mt_logic(blink.SelectEvery(4,2),
\                blink.SelectEvery(4,3),
\                mode="or").ConvertToRGB32()

    f0=Layer(clp.SelectEvery(4,0),
\            clp.SelectEvery(4,1).Mask(m01),
\            level=level)
    f1=Layer(clp.SelectEvery(4,1),
\            clp.SelectEvery(4,0).Mask(m01),
\            level=level)
    f2=Layer(clp.SelectEvery(4,2),
\            clp.SelectEvery(4,3).Mask(m23),
\            level=(257-level) )
    f3=Layer(clp.SelectEvery(4,3),
\            clp.SelectEvery(4,2).Mask(m23),
\            level=(257-level) )

    Interleave(f0,f1,f2,f3)
}

function ng_blinkmask(clip clp,
\ bool "TEST",
\ bool "STABILIZE",
\ bool "SHARP",
\ bool "HYSTER",
\ int "inpand",
\ int "expand",
\ int "ml"
\){
#Version 10 2012.04.22

#BLINK
# Blinking is a block that alternates on/off each frame
# SelectEven would only see either the on or the off

#FLASH
# Flashing is a block that is only on for a single frame
# SelectEven might miss the flash

#SHAKE
# Shaking is a block that moves back/forth each frame
# SelectEven would only see one position

# The goal of this function is to make a blink mask for use with
# ng_deblink. For overly complicated scenes where a clean blinkmask
# can't be found, just use TASBlend. Uniform softness looks better
# than sharp artifacts.

# This function calculates flash and shake info for the test script,
# but those effects should be handled in different ways.
# Flash - choose frames to make sure the flash is in your final clip.
# Shake - SelectEvery(4,0,2,1,3) or SelectEvery(4,1,0,2,3)
# SelectEvery doesn't generally work because it messes with the fluidity
# of motion. But that won't be noticable on a shaking screen.
# Be careful if 2 frame blinking is present, as the selectevery can turn
# it into 1 frame blinking.

    TEST      = default(     TEST, false)
    STABILIZE = default(STABILIZE, true)
    SHARP     = default(    SHARP, true)
    HYSTER    = default(   HYSTER, false)
    inpand    = default(   inpand, 1)
    expand    = default(   expand, 1)
    ml        = default(       ml, 128)

# The functions used to make the masks work in the YV12 colorspace. Once
# the masks are created they can be used in the RGB32 colorspace direcly
    src=clp.ConvertToYV12()

# Blinking is located by looking for blocks that don't exist in
# consecutive frames. The motion vector will match blocks that exist in
# both frames. The blocks that aren't in both will end up with huge
# values that are picked out by the motion mask.
    super = MSuper(src, pel=1)
    fvec  = MAnalyse(super, isb=false, blksize=4)
    bvec  = MAnalyse(super, isb=true , blksize=4)
    fmask = Mmask(src, fvec, kind=1, ml=ml).mt_binarize()
    bmask = Mmask(src, bvec, kind=1, ml=ml).mt_binarize()
    blink = mt_logic(fmask, bmask, mode="and")

# Blinking usually occurs against a stable background. This is found
# by looking at blocks 2 frames apart. This distinguishes a blink from
# blocks that are just changing every frame.
    ee_src   = src.SelectEven()
    ee_super = MSuper(ee_src, pel=1)
    ee_fvec  = MAnalyse(ee_super, isb=false, blksize=4)
    ee_bvec  = MAnalyse(ee_super, isb=true , blksize=4)
    ee_fmask = Mmask(ee_src, ee_fvec, kind=1, ml=ml).mt_binarize()
    ee_bmask = Mmask(ee_src, ee_bvec, kind=1, ml=ml).mt_binarize()

    oo_src   = src.SelectOdd()
    oo_super = MSuper(oo_src, pel=1)
    oo_fvec  = MAnalyse(oo_super, isb=false, blksize=4)
    oo_bvec  = MAnalyse(oo_super, isb=true , blksize=4)
    oo_fmask = Mmask(oo_src, oo_fvec, kind=1, ml=ml).mt_binarize()
    oo_bmask = Mmask(oo_src, oo_bvec, kind=1, ml=ml).mt_binarize()

    fmask_2   = Interleave(ee_fmask, oo_fmask)
    bmask_2   = Interleave(ee_bmask, oo_bmask)
    background = mt_logic(fmask_2.SelectEvery(1,1),
\                         bmask_2.SelectEvery(1,-1),
\                         mode="or")
    stable_blink = mt_hysteresis(background.mt_invert, blink)
    blink2 = (STABILIZE) ? stable_blink : blink

# Shrinking the blink mask can get rid of noise,
# too much will lose signal as well.
    blink3 = blink2.mt_inpand(mode=mt_diamond(inpand))

# Using just pixels that changed helps sharpen the mask
    diff   = ng_diff(clp.SelectEvery(1,-1), clp)
    diff_2 = mt_logic(diff, diff.SelectEvery(1,1), mode="and")

#Hysteresis
# Matches continuous blocks of pixels.
# Use with care, will match the whole screen on fades.
    hyster_blink = mt_hysteresis(blink3, diff_2)

# Expand the mask to make up for shrinking it (or just use hysteresis)
    blink4 = blink3.mt_expand(mode=mt_circle(expand))
    sharp_blink = mt_logic(blink4, diff_2, mode="and")

    blink5 = (HYSTER) ? hyster_blink :
\            (SHARP)  ? sharp_blink  : blink4


# A flash won't match blocks 1 or 2 frames away.
    sub_flash = mt_logic(fmask_2, bmask_2, mode="and")
    flash     = mt_logic(blink, sub_flash, mode="and")

# A shake changes in one frame and changes back in the next.
# This isn't detected by the motion vectors because the blocks exist in
# both frames, they are just shifting around.
    same   = ng_same(clp.SelectEvery(1,-1), clp.SelectEvery(1,1))
    shake  = mt_logic(same, diff_2, mode="and")

    (TEST) ? stackhorizontal(clp, mergeRGB(blink5, flash, shake))
\          : blink5.GreyScale()
}

function ng_diff(clip A, clip B, int "thr"){
    thr=default(thr,0)
    TAD=ng_TAD(A,B)
    return mt_binarize(TAD, threshold=thr)
}

function ng_same(clip A, clip B, int "thr"){
    thr=default(thr,0)
    TAD=ng_TAD(A,B)
    return mt_binarize(TAD, threshold=thr, upper=true)
}

function ng_TAD(clip A, clip B){
    R=ng_AD(A  .showRed("YV12"),B  .showRed("YV12"))
    G=ng_AD(A.showGreen("YV12"),B.showGreen("YV12"))
    B=ng_AD(A .showBlue("YV12"),B .showBlue("YV12"))
    return ng_plus(R, ng_plus(G, B))
}

function ng_AD(clip A, clip B){
    return mt_lutxy(A,B,"x y - abs")
}

function ng_plus(clip A, clip B){
    return mt_lutxy(A,B,"x y +")
}