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olofsen/rs.jl

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Reading, displaying, and converting a Sixel Graphics file with Julia
Raw
LICENSE.md

The rs.jl package is licensed under the MIT "Expat" License:

Copyright (c) 2014: Erik Olofsen.

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Raw
rs.jl
using Color, Images, ImageView
function vt340_palette()
pal = RGB[]
push!(pal, RGB(0.00, 0.00, 0.00))
push!(pal, RGB(0.20, 0.20, 0.80))
push!(pal, RGB(0.80, 0.13, 0.13))
push!(pal, RGB(0.20, 0.80, 0.20))
push!(pal, RGB(0.80, 0.20, 0.80))
push!(pal, RGB(0.20, 0.80, 0.80))
push!(pal, RGB(0.80, 0.80, 0.20))
push!(pal, RGB(0.53, 0.53, 0.53))
push!(pal, RGB(0.26, 0.26, 0.26))
push!(pal, RGB(0.33, 0.33, 0.60))
push!(pal, RGB(0.60, 0.26, 0.26))
push!(pal, RGB(0.33, 0.60, 0.33))
push!(pal, RGB(0.60, 0.33, 0.60))
push!(pal, RGB(0.33, 0.60, 0.60))
push!(pal, RGB(0.60, 0.60, 0.33))
push!(pal, RGB(0.80, 0.80, 0.80))
pal
end
type SixelFile
s::Array{Uint8}
nc::Int
lc::Int
bc::Int
ip::Int
cp::Int
c::Char
hd::Bool
err::Bool
pars::Array{Int}
function SixelFile()
new(zeros(Uint8,0), 0, 0, 0, 0, 1, '\0', false, false, zeros(Int,7))
end
end
function readSixels(sf::SixelFile, filnam::String)
f = open(filnam,"r")
sf.s = read(f,Uint8,filesize(filnam));
sf.nc = length(sf.s)
close(f)
end
function sixel(sf::SixelFile)
while true
sf.ip += 1
if sf.ip>sf.nc; sf.err=true; return; end
sf.c = sf.s[sf.ip]
if sf.c=='\e' || sf.c>' '; break; end
end
end
function number(sf::SixelFile)
k = 0
while true
sixel(sf)
if sf.err; return -1; end
if sf.c<'0' || sf.c>'9'; return k; end
k = k*10 + (int(sf.c)-int('0'));
end
end
function header(sf::SixelFile)
if sf.c=='\e'
sixel(sf)
if sf.c!='P'; return; end
end
ip = 0
while true
n = number(sf)
if sf.err; return; end
if sf.c=='q'; break; end
ip += 1
sf.pars[ip] = n
end
sixel(sf)
if sf.err; return; end
if sf.c=='"'
ip = 3
while true
n = number(sf)
if n<0; break; end
ip += 1
sf.pars[ip] = n
if sf.c!=';'; break; end
end
end
sf.hd = true
end
function color(sf::SixelFile)
k = number(sf)
k = rem(k,16)
sf.cp = k+1
if sf.c!=';'; return; end
d = number(sf)
if sf.c!=';'; return; end
r = number(sf)
if sf.c!=';'; return; end
g = number(sf)
if sf.c!=';'; return; end
b = number(sf)
end
function color(sf::SixelFile, p::Array)
k = number(sf)
k = rem(k,16)
sf.cp = k+1
if sf.c!=';'; return; end
d = number(sf)
if sf.c!=';'; return; end
r = number(sf)
if sf.c!=';'; return; end
g = number(sf)
if sf.c!=';'; return; end
b = number(sf)
if d==1
p[sf.cp] = convert(RGB, HSL((r+240)%360, b/100, g/100))
elseif d==2
p[sf.cp] = RGB(r/100,g/100,b/100)
end
end
function getcolor(cp, p::Array{RGB,1})
[iround(p[cp].r*255), iround(p[cp].g*255), iround(p[cp].b*255)]
end
function clear(sf::SixelFile, img::Image, col::Array)
for j=1:size(img.data,3), i=1:size(img.data,2)
img[:,i,j] = col
end
end
# get dimensions and colors
function pass1(sf::SixelFile, p::Array{RGB,1})
sf.lc = 0
sf.bc = 0
sf.ip = 0
sf.hd = false
sf.err = false
bc = 0
sixel(sf)
while !sf.err
c = sf.c
if c=='\e' || c=='\u90' || c=='\u9c'
if sf.hd; break; end
header(sf)
c = sf.c
end
if !sf.hd; sixel(sf); continue; end
if c=='$'
if bc>sf.bc; sf.bc=bc; end
bc = 0
sixel(sf)
elseif c=='-'
if bc>sf.bc; sf.bc=bc; end
sf.lc += 1
bc = 0
sixel(sf)
elseif c=='#'
color(sf,p)
elseif c=='!'
k = number(sf)
bc += k
sixel(sf)
else
bc += 1
sixel(sf)
end
end
end
function putsixel(sf::SixelFile, img::Image, col::Array, lc::Int, bc::Int, k::Int)
msk::Uint8
ic::Uint8
msk = 0x01
ic = int(sf.c)-63
xs = size(img.data,2)
ys = size(img.data,3)
for j=1:6
if ic&msk>0
for i=1:k
x = bc+i
y = lc*6+j
if x<=xs && y<=ys; img[:,x,y] = col; end
end
end
msk <<= 1
end
end
# put the sixels in the image
function pass2(sf::SixelFile, img::Image, p::Array)
bc::Int
lc::Int
bc = 0
lc = 0
sf.ip = 0
sf.hd = false
sf.err = false
col = getcolor(1,p)
sixel(sf)
while !sf.err
c = sf.c
if c=='\e' || c=='\u90' || c=='\u9c'
if sf.hd; break; end
header(sf)
c = sf.c
end
if !sf.hd; sixel(sf); continue; end
if c=='$'
bc = 0
sixel(sf)
elseif c=='-'
lc += 1
bc = 0
sixel(sf)
elseif c=='#'
color(sf)
col = getcolor(sf.cp, p)
elseif c=='!'
k = number(sf)
putsixel(sf, img, col, lc, bc, k)
bc += k
sixel(sf)
else
putsixel(sf, img, col, lc, bc, 1)
bc += 1
sixel(sf)
end
end
end
function ds(filnam::String, bg::Int=0)
sf = SixelFile()
readSixels(sf, filnam)
p = vt340_palette()
pass1(sf,p)
if sf.err; return sf; end
if sf.pars[6]>0; xs = sf.pars[6]; else; xs = sf.bc; end
if sf.pars[7]>0; ys = sf.pars[7]; else; ys = sf.lc*6; end
img = Image(Array(Uint8,3,xs,ys),
["limits"=>(0x00,0xff),
"colordim"=>1,
"spatialorder"=>["x","y"],
"colorspace"=>"RGB"])
if bg==0
clear(sf, img, getcolor(1,p))
elseif bg==1
clear(sf, img, [0, 0, 0])
elseif bg==2
clear(sf, img, [0xff, 0xff, 0xff])
end
pass2(sf, img, p)
display(img)
img
end
# img = ds("")
# imwrite(img,"")
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