dither
height:
px
rgba→mono:
return(col[0]*.298912+col[1]*.586611+col[2]*.114478)*col[3]+0*(1-col[3]);
dither:
[//→,↓,weight //Floyd-Steinberg //[ 1,0,7/16],[-1,1,3/16],[ 0,1,5/16],[ 1,1,1/16] //Atkinson [ 1,0,1/8],[ 2,0,1/8],[-1,1,1/8],[ 0,1,1/8],[ 1,1,1/8],[ 0,2,1/8] ]
gap:
padding:
run