tgRead.m

function [textgrid, fid] = tgRead(fileName, encoding)
% function textgrid = tgRead(fileName)
%
% Loads TextGrid from Praat in Text or Short text format,
% it handles both Interval and Point tiers.
% Labels may contain quotation marks and new lines.
%
% fileName ... file name of TextGrid
% encoding ... [optional, default: 'UTF-8'] file encoding, 'auto' for Unicode
%              standard autodetection
%
% Tomas Boril, borilt@gmail.com + Pol van Rijn
%
% Example
%   tg = tgRead('demo/H.TextGrid');
%   tgPlot(tg);

textgrid = [];
if ~isnumeric(fileName)
    % means it is not a collection!
    if nargin < 2
        encoding = 'UTF-8';
    end
    if strcmp(encoding, 'auto')
        encoding = tgDetectEncoding(fileName);
    end
    
    [fid, message] = fopen(fileName, 'r', 'n', encoding);
    if fid == -1
        error(['cannot open file [' fileName ']: ' message]);
    end
    
    for I = 1: 3
        r = fgetl(fid); % ignore
    end
else
    % encoding is never used
    fid = fileName;
end

xminStr = fgetl(fid); % xmin
xmaxStr = fgetl(fid); % xmax
r = fgetl(fid); % either '<exists>' -> shorttext or 'tiers? <exists> ' -> full text format
if ~isempty(strfind(r, 'tiers?'))
    shortFormat = false;
elseif ~isempty(strfind(r, '<exists>'))
    shortFormat = true;
else
    fclose(fid);
    error('Unknown textgrid format.');
end

xmin = getNumberInLine(xminStr, shortFormat);
xmax = getNumberInLine(xmaxStr, shortFormat);

if shortFormat
    numberOfTiers = str2double(fgetl(fid));
else
    r = fgetl(fid);
    if r(end) ~= ' '
        sppasFormat = true;
    else
        sppasFormat = false;
    end
    r = textscan(r, 'size = %d');
    numberOfTiers = r{1};
end

for tier = 1: numberOfTiers
    if shortFormat
        typ = fgetl(fid);
    else
        r = strtrim(fgetl(fid));
        while strcmp(r(1:4), 'item') == 1
            r = strtrim(fgetl(fid));
        end
        if strcmp(r(1:9), 'class = "') ~= 1
            fclose(fid); error('unknown textgrid format');
        end
        typ = r(9:end);
    end
    if strcmp(typ, '"IntervalTier"') == 1  % IntervalTier
        r = fgetl(fid); % name
        if shortFormat
            textgrid.tier{tier}.name = r(2: end-1);
        else
            r = strtrim(r);
            textgrid.tier{tier}.name = r(9: end-1);
        end
        textgrid.tier{tier}.type = 'interval';
        
        r = fgetl(fid); % ignore xmin and xmax
        r = fgetl(fid);
        
        if shortFormat
            numberOfIntervals = str2double(fgetl(fid));
        else
            r = strtrim(fgetl(fid));
            numberOfIntervals = str2double(r(19:end));
        end
        
        textgrid.tier{tier}.T1 = [];
        textgrid.tier{tier}.T2 = [];
        textgrid.tier{tier}.Label = {};
        
        for I = 1: numberOfIntervals
            if ~shortFormat
                r = fgetl(fid); % ignore line intervals [..]:
            end
            
            if shortFormat
                t = str2double(fgetl(fid));
                t2 = str2double(fgetl(fid));
            else
                r1 = strtrim(fgetl(fid));
                r2 = strtrim(fgetl(fid));
                if strcmp(r1(1:7), 'xmin = ') ~= 1  ||  strcmp(r2(1:7), 'xmax = ') ~= 1
                    fclose(fid); error('unknown textgrid format');
                end
                t = str2double(r1(8:end));
                t2 = str2double(r2(8:end));
            end
            
            r = fgetl(fid);
            if ~shortFormat
                if isempty(strfind(r, 'text = "'))
                    fclose(fid); error('unknown textgrid format');
                end
                rind = strfind(r, '"');
                numberOfQuotationMarks = sum(r == '"');
                if mod(numberOfQuotationMarks, 2) ~= 1 % remove whitespace at the end of line, it is only in the case of even number of quotation marks
                    if sppasFormat ~= true
                        r = r(rind(1): end-1);
                    else
                        r = r(rind(1): end);
                    end
                else
                    r = r(rind(1): end);
                end
            end
            numberOfQuotationMarks = sum(r == '"');
            label = r(2:end);
            if mod(numberOfQuotationMarks, 2) == 1
                label = [label sprintf('\n')];
                while 1
                    r = fgetl(fid);
                    numberOfQuotationMarks = sum(r == '"');
                    if ~shortFormat && mod(numberOfQuotationMarks, 2) == 1 && ~sppasFormat % remove whitespace at the end of line, it is only in the case of odd number of quotation marks
                        r = r(1: end-1);
                    end
                    
                    if mod(numberOfQuotationMarks, 2) == 1 && r(end) == '"'
                        label = [label r(1:end-1) '"'];
                        break
                    else
                        label = [label sprintf([r '\n'])];
                    end
                    
                end
            end
            label = label(1: end-1);
            if isempty(label)
                label = '';   % unification: '' and Empty string: 1-by-0  
            end
            
            textgrid.tier{tier}.T1 = [textgrid.tier{tier}.T1 t];
            textgrid.tier{tier}.T2 = [textgrid.tier{tier}.T2 t2];
            textgrid.tier{tier}.Label{1, I} = label; % trim quotation marks
            
            xmin = min(t, xmin); xmin = min(t2, xmin);
            xmax = max(t, xmax); xmax = max(t2, xmax);
        end
        
        
    elseif strcmp(typ, '"TextTier"') == 1  % PointTier
        r = fgetl(fid); % name
        if shortFormat
            textgrid.tier{tier}.name = r(2: end-1);
        else
            r = strtrim(r);
            textgrid.tier{tier}.name = r(9: end-1);
        end
        textgrid.tier{tier}.type = 'point';
        
        r = fgetl(fid); % ignore xmin and xmax
        r = fgetl(fid);
        
        if shortFormat
            numberOfIntervals = str2double(fgetl(fid));
        else
            r = strtrim(fgetl(fid));
            numberOfIntervals = str2double(r(16:end));
        end
        
        textgrid.tier{tier}.T = [];
        textgrid.tier{tier}.Label = {};
        
        for I = 1: numberOfIntervals
            if ~shortFormat
                r = fgetl(fid); % ignore line points [..]:
            end
            
            if shortFormat
                t = str2double(fgetl(fid));
            else
                r = strtrim(fgetl(fid));
                if strcmp(r(1:9), 'number = ') ~= 1
                    fclose(fid); error('unknown textgrid format');
                end
                t = str2double(r(10:end));
            end
            
            r = fgetl(fid);
            if ~shortFormat
                if isempty(strfind(r, 'mark = "'))
                    fclose(fid); error('unknown textgrid format');
                end
                rind = strfind(r, '"');
                numberOfQuotationMarks = sum(r == '"');
                if mod(numberOfQuotationMarks, 2) ~= 1 % remove whitespace at the end of line, it is only in the case of even number of quotation marks
                    if sppasFormat ~= true
                        r = r(rind(1): end-1);
                    else
                        r = r(rind(1): end);
                    end
                else
                    r = r(rind(1): end);
                end
            end
            numberOfQuotationMarks = sum(r == '"');
            label = r(2:end);
            if mod(numberOfQuotationMarks, 2) == 1
                label = [label sprintf('\n')];
                while 1
                    r = fgetl(fid);
                    numberOfQuotationMarks = sum(r == '"');
                    if ~shortFormat && mod(numberOfQuotationMarks, 2) == 1 && ~sppasFormat % remove whitespace at the end of line, it is only in the case of odd number of quotation marks
                        r = r(1: end-1);
                    end
                    
                    if mod(numberOfQuotationMarks, 2) == 1 && r(end) == '"'
                        label = [label r(1:end-1) '"'];
                        break
                    else
                        label = [label sprintf([r '\n'])];
                    end
                    
                end
            end
            label = label(1: end-1);
            
            if isempty(label)
                label = '';   % unification: '' and Empty string: 1-by-0  
            end
            
            textgrid.tier{tier}.T = [textgrid.tier{tier}.T t];
            textgrid.tier{tier}.Label{1, I} = label; % trim quotation marks
            
            xmin = min(t, xmin);
            xmax = max(t, xmax);
        end
    else  % unknown tier
        fclose(fid);
        error('Unknown tier type - IntervalTier and PointTier are supported only.');
    end
    
end

if ~isnumeric(fileName)
    fclose(fid);
end

textgrid.tmin = xmin;
textgrid.tmax = xmax;