a

1 files changed, 46 insertions, 0 deletions

diff --git a/config/mpv/scripts/subs2srsa/utils/base64.lua b/config/mpv/scripts/subs2srsa/utils/base64.lua
new file mode 100644
index 0000000..0fe2d06
--- /dev/null
+++ b/config/mpv/scripts/subs2srsa/utils/base64.lua
@@ -0,0 +1,46 @@
+--[[
+Copyright: Ren Tatsumoto and contributors
+License: GNU GPL, version 3 or later; http://www.gnu.org/licenses/gpl.html
+
+Encoding and decoding in base64
+]]
+
+-- http://lua-users.org/wiki/BaseSixtyFour
+
+-- character table string
+local b = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
+
+-- encoding
+local function enc(data)
+    return ((data:gsub('.', function(x)
+        local r,b='',x:byte()
+        for i=8,1,-1 do r=r..(b%2^i-b%2^(i-1)>0 and '1' or '0') end
+        return r;
+    end)..'0000'):gsub('%d%d%d?%d?%d?%d?', function(x)
+        if (#x < 6) then return '' end
+        local c=0
+        for i=1,6 do c=c+(x:sub(i,i)=='1' and 2^(6-i) or 0) end
+        return b:sub(c+1,c+1)
+    end)..({ '', '==', '=' })[#data%3+1])
+end
+
+-- decoding
+local function dec(data)
+    data = string.gsub(data, '[^'..b..'=]', '')
+    return (data:gsub('.', function(x)
+        if (x == '=') then return '' end
+        local r,f='',(b:find(x)-1)
+        for i=6,1,-1 do r=r..(f%2^i-f%2^(i-1)>0 and '1' or '0') end
+        return r;
+    end):gsub('%d%d%d?%d?%d?%d?%d?%d?', function(x)
+        if (#x ~= 8) then return '' end
+        local c=0
+        for i=1,8 do c=c+(x:sub(i,i)=='1' and 2^(8-i) or 0) end
+        return string.char(c)
+    end))
+end
+
+return {
+    enc = enc,
+    dec = dec,
+}