replace_png_by_jpg(htmlfile)

function replace_png_by_jpg(htmlfile)
% REPLACE_PNG_BY_JPG does exchange the .png string by .jpg
% 
%   These is usefull, if you want to use another Screenshots in your
%   published HTML-File with the extention JPG instead of selected default
%   PNG.
%  
%   Syntax: >> replace_png_by_jpg('HTML_File')
%
%   See Also: NEWFCN_RENAME PUBLISH_TECHNICS

%% AUTHOR    : Frank Gonzalez-Morphy 
%% $DATE     : 28-Jul-2004 18:00:35 $ 
%% $Revision : 1.00 $ 
%% DEVELOPED : 7.0.0.19920 (R14) 
%% FILENAME  : replace_png_by_jpg.m 

if nargin == 0, help(mfilename); return, end

ext_htmlfile = '.html';               % default extension
s = strfind(htmlfile,ext_htmlfile);   % does have input .html extension ?
if isempty(s)
    htmlfile_ext = [htmlfile ext_htmlfile]; % complete filename
else
    htmlfile_ext = htmlfile;          % filename with extension
end

dir_pwd = pwd;                        % remember actual directory
if exist(htmlfile_ext) == 0           % not in current directory
    mfile = htmlfile_ext(1,1:end-5);  % search for M-File ~ publish
    w = which(mfile);                 % saving place of M-File
    if isempty(w)                     % M-File not known in ML Path
        error(['   MSG: M-File ' , mfile , ' couldn''t be found!'])
    end
    [pathstr,name,ext,versn] = fileparts(w); % otherwise separate fileparts
    cd([pathstr '\html'])                    % if published HTML file
    if exist(htmlfile_ext) == 0           % does exist ? if yes, go further
        cd(dir_pwd)                       % if error happens, back to workdir
        error(['   MSG: HTML File ' , htmlfile_ext , ' doesn''t exist or couldn''t found!'])
    end
end

% Open source File for Reading content
fid = fopen(htmlfile_ext, 'r');
% ... scan the Text content ...
Scaned_Text   = fscanf(fid, '%c', inf);
% ... Close the File.
fclose(fid);

% Extensions
jpg_str = '.jpg"';
png_str = '.png"';
% Sizes of the Extensions
sz_jpg     = size(jpg_str,2);
sz_png     = size(png_str,2);

% Position of extention PNG in scaned Text
Start_Pos_png  = findstr(png_str, Scaned_Text);
% Renaming Scaned Text with another Extention: JPG
Modified_Text = [Scaned_Text(1,1:Start_Pos_png-1) jpg_str, ...
    Scaned_Text(1,Start_Pos_png+sz_jpg:end)];

% Open File for Writing modified content discarting original content
fid = fopen(htmlfile_ext, 'w');
% ... write the modified content
fprintf(fid, '%s', Modified_Text);
% ... and close the File
st = fclose(fid);
if st == 0  % done well ? yes, go further
    disp(['   MSG: In <' htmlfile_ext '> .png replaced by .jpg !'])
    % NOTE: Open file in MATLAB Editor / Debugger, if already opened it
    % should be automatically updated !  BUG = these doesn't happen if
    % Editor window of file content is highlighted. First changing forward
    % and backward the content will be reloaded and updated.
    edit(htmlfile_ext);  % Edit the modified File on the Editor
    cd(dir_pwd)          % return to started directory
end


% Created with NEWFCN.m by Frank Gonzlez-Morphy  
% Contact...: [e-mail]  
% ===== EOF ====== [replace_png_by_jpg.m] ======