convertDirToDng.m

%
%% convertDirToDng
%
% Converts a directory of raw images into uncompressed DNGs
%
% _Parameters_
% * sourceDir       - Directory containing source DNGs to convert.
% * sourceDirMask   - Mask of files to convert (or empty for all files)
% * destDir         - Directory to store converted DNGs
%
% _Return Values_
% * success         - true if successful, false if not.
% * numDngsCreated  - number of files converted
%
function [success, numDngsCreated] = convertDirToDng(sourceDir, sourceDirMask, destDir)

  timeStart = tic();

  %
  % Adobe's DNG converter is heavily optimized for parallel operation, provided
  % it's supplied multiple files to convert per invocation. I place an arbitrary
  % limit on the number of files per invocation, to keep the size of the command
  % line reasonable for situations where there are hundreds of files to process
  %
  % Note that running the DNG converter's GUI is much faster than invoking
  % from the command line, even when we pass it the full list of files on
  % the command line :(
  %
  MAX_FILES_PER_CONVERSION  = 32;

  success = false; % assume error
  numDngsCreated = 0;

  % get listing of files in specified source directory
  listing = dir(fullfile(sourceDir, sourceDirMask));
  numEntriesInListing = numel(listing);

  %
  % process files in directory
  %
  firstFileThisConversion = 1;
  numFilesConverted = 0;
  while (firstFileThisConversion <= numEntriesInListing)

    %
    % build file list of up to MAX_FILES_PER_CONVERSION files to process on
    % this invocation. Note we select any file in the directory, which means
    % the directory must only containimage files, otherwise the DNG converter
    % will fail when it reaches the non-image file.
    %
    numFilesThisConversion = 0;
    fileListStr = '';
    nextFileThisConversion = firstFileThisConversion;
    while (nextFileThisConversion <= numEntriesInListing && numFilesThisConversion < MAX_FILES_PER_CONVERSION)
      % skip directories and filenames beginning with '.' (hidden files, to prevent .DS_Store and metadata files on OSX)
      if (~listing(nextFileThisConversion).isdir && listing(nextFileThisConversion).name(1) ~= '.')
        %
        % if source mask is not empty then we use all files generated by dir()
        % uncondtionally (we assume user/caller used an appropriate file mask).
        % if source mask is empty then we select all filenames that have
        % extensions indicating they are are files.
        %
        if (~isempty(sourceDirMask) || isFilenameRawImageFile(listing(nextFileThisConversion).name))
          fileListStr = [fileListStr '"' fullfile(listing(nextFileThisConversion).folder, listing(nextFileThisConversion).name) '" '];
          numFilesThisConversion = numFilesThisConversion+1;
        end
      end
      nextFileThisConversion = nextFileThisConversion +1;
    end

    % perform the conversion
    if (numFilesThisConversion > 0)
      [exitCode, output] = runDngConverter(['-u -d "' destDir '" ' fileListStr]);
      if (exitCode ~= 0)
        if (~isempty(sourceDirMask))
          fprintf(['\n*** Note: DNG conversion will fail if there are any non-raw images '...
            'in the directory included in your file mask (' sourceDirMask '), including any hidden files '...
            'like .DS_Store on OSX\n']);
        end
        return;
      end
      numFilesConverted = numFilesConverted + numFilesThisConversion;
    end

    % advance outer processing loop index to pick up after the last file we just converted
    firstFileThisConversion = nextFileThisConversion;
  end

  success = true;
  numDngsCreated = numFilesConverted;

  if (numDngsCreated > 0)
    fprintf('Adobe DNG Converter: %d DNGs converted in %.2f seconds\n', numDngsCreated, toc(timeStart));
  else
    if (isempty(sourceDirMask))
      fprintf('\nNo raw image files were found in "%s"\n\n', sourceDir);
    else
      fprintf('\nNo files matching for your file mask were found in "%s"\n', sourceDir);
      fprintf('Make sure the case of your mask (%s) matches the case of the filenames in the directory (case-sensitive)\n\n', sourceDirMask);
    end
  end

end