Modified VLC YouTube playlist parsing script to support playlists with more than 200 videos. Verified it works with 1000+ videos, no duplicates and all included (minus deleted videos). Official version claims to support 100+, but actually only works up until 200 videos. https://addons.videolan.org/content/show.php/+Youtube+playlist?content=149909

149909-playlist_youtube.lua

--[[
 Youtube playlist importer for VLC media player 1.1 and 2.0
 Copyright 2012 Guillaume Le Maout

 Authors:  Guillaume Le Maout
 Contact: http://addons.videolan.org/messages/?action=newmessage&username=exebetche

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation; either version 2 of the License, or
 (at your option) any later version.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.

 You should have received a copy of the GNU General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
--]]

--[[
 MODified by Kai Gillmann, 19.01.2013, kaigillmann@googlemail.com:
 VLC HAS already a youtube importer, but not for playlists. IMO this mentioned one is
 better than this one, because it opens the video in the best possible video resolution.
 So i decided to remove all parts of the code which is not responsible for list handling.
 Now this lua script parses the list, as wanted, but for each video opened, the vlc default
 Youtube script is used, so the videos will be displayed properly.
--]]

--[[
 Patched by Aaron Hill (https://github.com/seraku24), 2018-05-16:
 The original script was failing in VLC 3.x due to an overzealous probe function.
 This patch makes the probe function more restrictive to avoid false positives.
--]]

-- Helper function to get a parameter's value in a URL
function get_url_param( url, name )
     local _, _, res = string.find( url, "[&?]"..name.."=([^&]*)" )
     return res
end

-- Probe function.
function probe()
     if vlc.access ~= "http" and vlc.access ~= "https" then
	     return false
     end

     return string.match(vlc.path:match("([^/]+)"),"%w+.youtube.com") and (
			 not string.match(vlc.path, "list_ajax") and string.match(vlc.path, "[?&]list="))
end

-- Parse function.
function parse()
	if string.match( vlc.path, "list=" ) then
		local playlist_parsed, playlistData, line, s, item
		local p = {}
		local id_ref = {}
		local index = 100
		local playlistID = get_url_param( vlc.path, "list" )
		local videoID = get_url_param( vlc.path, "v" )
		local playlistURL = "http://www.youtube.com/list_ajax?action_get_list=1&style=xml&list="..playlistID
		local prevLoaded = 0

		while true do
			playlistData = ""
			line = ""
			s = nil
			s = vlc.stream(playlistURL.."&index="..index)
			while line do
				playlistData = playlistData..line
				line = s:readline()
			end

			playlist_parsed = nil
			playlist_parsed = parse_xml(playlistData).root.video

			for i, video in ipairs(playlist_parsed) do
				if not id_ref[video.encrypted_id.CDATA] then

					vlc.msg.err(i.." "..video.encrypted_id.CDATA)
					id_ref[video.encrypted_id.CDATA] = true
					
					item = nil
					item = {}

					if video.encrypted_id
					and video.encrypted_id.CDATA then
						item.path = "http://www.youtube.com/watch?v="..video.encrypted_id.CDATA
					end

					if video.title
					and video.title.CDATA then
						item.title = video.title.CDATA
					end

					if video.artist
					and video.artist.CDATA then
						item.artist = video.artist.CDATA
					end

					if video.thumbnail
					and video.thumbnail.CDATA then
						item.arturl = video.thumbnail.CDATA
					end

					if video.description
					and video.description.CDATA then
						item.description = video.description.CDATA
					end

					--~ item.rating = video.rating
					table.insert (p, item)

				end
			end
			if #p > prevLoaded then
				index = index +100
				prevLoaded = #p
			else
				return p
			end
		end
	end
end


function parse_xml(data)
	local tree = {}
	local stack = {}
	local tmp = {}
	local tmpTag = ""
	local level = 0

	table.insert(stack, tree)

	for op, tag, attr, empty, val in string.gmatch(
		data,
		"<(%p?)([^%s>/]+)([^>]-)(%/?)>[%s\r\n\t]*([^<]*)[%s\r\n\t]*") do
		if op=="?" then
			--~ DOCTYPE
		elseif op=="/" then
			if level>0 then
			level = level - 1
			table.remove(stack)
			end
		else
		level = level + 1

		if op=="!" then
			stack[level]['CDATA'] = vlc.strings.resolve_xml_special_chars(
			string.gsub(tag..attr, "%[CDATA%[(.+)%]%]", "%1"))
			attr = ""
			level = level - 1
		elseif type(stack[level][tag]) == "nil" then
			stack[level][tag] = {}
			table.insert(stack, stack[level][tag])
		else
			if type(stack[level][tag][1]) == "nil" then
			 tmp = nil
			 tmp = stack[level][tag]
			 stack[level][tag] = nil
			 stack[level][tag] = {}
			 table.insert(stack[level][tag], tmp)
			end
			tmp = nil
			tmp = {}
			table.insert(stack[level][tag], tmp)
			table.insert(stack, tmp)
			end

			if val~="" then
			stack[level][tag]['CDATA'] = {}
			stack[level][tag]['CDATA'] = vlc.strings.resolve_xml_special_chars(val)
			end

			if attr ~= "" then
			stack[level][tag]['ATTR'] = {}
				string.gsub(attr,
				"(%w+)=([\"'])(.-)%2",
				function (name, _, value)
				 stack[level][tag]['ATTR'][name] = value
				end)
			end

			if empty ~= "" then
				level = level - 1
				table.remove(stack)
			end
		end
	end
	return tree
end