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Posted: **04 Jul 2014 13:44**

Prompted by Suncatcher's post on the *nix forum, and wanting the same thing, I took a crash course in Lua and hacked cue.lua to stream each track on a cuesheet to a separate mp3 file. Developed on Windoze, and I haven't tested it on Linux. It probably should be implemeted as an extension with some configuration options, but would need more time for that. Put this file in your lua/playlist/ folder. Re-name your cuesheet from foo.cue to foo.cue2mp3 and just drag it into vlc.

HOWEVER, there are two issues. Using the --start-time and --stop-time switches using the default cue interpreter rounds down times to the nearest second. I don't know why this is - did an older version of vlc require an integer here? Removing the math.floor() function from cue.lua fixes it as expected. Issue 2 is that even though this fix finds the start and end of each track correctly when playing the file, it doesn't work when streaming. Vlc seems by default to round start times down to the nearest 10 seconds and round stop times up similarly. So each mp3 has a few seconds of the previous track at the beginning and a few seconds of the next track at the end. It would be good to know why this is, and whether it can be fixed. Meanwhile this script is useless

but I thought I would put it out for discussion.

Code: Select all

--[[
   Parse CUE file and transcode each track to mp3

 $Id$
 Copyright (C) 2014 Graham Horner
 using code Copyright (C) 2009 Laurent Aimar


 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.
--]]

-- Probe function.
function probe()
    if( not string.match( string.upper( vlc.path ), ".CUE2MP3$" ) ) then
        return false
    end
    header = vlc.peek( 2048 )
    return string.match( header, "FILE.*WAVE%s*[\r\n]+" ) or
           string.match( header, "FILE.*AIFF%s*[\r\n]+" ) or
           string.match( header, "FILE.*MP3%s*[\r\n]+" )
end

-- Helpers
function is_utf8( src )
    return vlc.strings.from_charset( "UTF-8", src ) == src
end

function cue_string( src )
    if not is_utf8( src ) then
        -- Convert to UTF-8 since it's probably Latin1
        src = vlc.strings.from_charset( "ISO_8859-1", src )
    end
    local sub = string.match( src, "^\"(.*)\".*$" );
    if( sub ) then
        return sub
    end
    return string.match( src, "^(%S+).*$" )
end

function cue_path( src )
    if( string.match( src, "^/" ) or
        string.match( src, "^\\" ) or
        string.match( src, "^[%l%u]:\\" ) ) then
        return string.sub( vlc.strings.make_uri(src), 1 )
    end

    local slash = string.find( string.reverse( vlc.path ), '/' )
        local prefix = vlc.access .. "://" .. string.sub( vlc.path, 1, -slash )
        -- FIXME: postfix may not be encoded correctly (esp. slashes)
        local postfix = vlc.strings.encode_uri_component(src)
    return prefix .. postfix
end

function cue_track( global, track )
    if( track.index01 == nil ) then
        return nil
    end

    t = {}
    t.path = cue_path( track.file or global.file )
    t.title = track.title or global.title
    t.name = track.title or global.title
    t.album = global.title
    t.artist = track.performer or global.performer
    t.genre = track.genre or global.genre
    t.date = track.date or global.date
    t.description = global.comment
    t.tracknum = track.num
	-- we need to construct the full file path for the destination using vlc.path
	-- vlc.path is written with forward slashes and has a slash at the beginning, before C:/
	local slash = string.find( string.reverse( vlc.path ), '/' )
	local filepath = string.sub( vlc.path, 2, -slash ) .. track.num .. " " ..
		string.gsub(track.title, "[\\/?:*\"><|]" , "-") .. ".mp3"
	if( string.find(track.file, "\\") ) then  -- track.file seems the only place where the platform filesystem separators are preserved
		filepath = string.gsub(filepath,  "/", "\\")
	end
    t.options = { ":start-time=" .. track.index01 , -- rounding down removed here
		':sout=#transcode{vcodec=none,acodec=mp3,ab=192,channels=2,samplerate=44100}:std{access=file,mux=raw,dst="' ..
		filepath ..'"' }

    return t
end

function cue_append( tracks, global, track )
    local t = cue_track( global, track )
    if( t ~= nil ) then
        if( #tracks > 0 ) then
            local prev = tracks[#tracks]
            table.insert( prev.options, ':stop-time=' .. track.index01 ) -- rounding down removed here
        end
        table.insert( tracks, t )
    end
end

-- Parse function.
function parse()
    p = {}
    global_data = nil
    data = {}
    file = nil

    while true
    do 
        line = vlc.readline()
        if not line then break end

        cmd, arg = string.match( line, "^%s*(%S+)%s*(.*)$" )

        if(  cmd == "REM" and arg ) then
            subcmd, value = string.match( arg, "^(%S+)%s*(.*)$" )
            if( subcmd == "GENRE" and value ) then
                data.genre = cue_string( value )
            elseif( subcmd == "DATE" and value ) then
                data.date = cue_string( value )
            elseif( subcmd == "COMMENT" and value ) then
                data.comment = cue_string( value )
            end
        elseif( cmd == "PERFORMER" and arg ) then
            data.performer = cue_string( arg )
        elseif( cmd == "TITLE" and arg ) then
            data.title = cue_string( arg )
        elseif( cmd == "FILE" ) then
            file = cue_string( arg )
        elseif( cmd == "TRACK" ) then
            if( not global_data ) then
                global_data = data
            else
                cue_append( p, global_data, data )
            end
            data =  { file = file, num = string.match( arg, "^(%d+)" ) }
        elseif( cmd == "INDEX" ) then
            local idx, m, s, f = string.match( arg, "(%d+)%s+(%d+):(%d+):(%d+)" )
            if( idx == "01" and m ~= nil and s ~= nil and f ~= nil ) then
                data.index01 = m * 60 + s + f / 75
            end
        end
    end

    cue_append( p, global_data, data )
    return p
end

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