Magic Lantern HDR video to tonemapped video with MATLAB scripts

ProcessHDRVideo.m

% Prerequisites (tested on Mac OS X 10.8.5):
% exiftool (tested with 9.37)
%   http://www.sno.phy.queensu.ca/~phil/exiftool/
% Luminance HDR (tested with 2.3.1)
%   http://qtpfsgui.sourceforge.net/

function ProcessHDRVideo(MOVIENAME,EVDIFF)
    % Include the audio
%     [y,Fs] = audioread(moviename);
%     filename = fullfile(workingDir,'images','audioTrack.wav');
%     audiowrite(filename,y,Fs);
%     clear y Fs

    inputVideo = VideoReader(MOVIENAME);

    Step1MovieToInterpolatedFrames(inputVideo,EVDIFF)
    Step2FramesToHDRFrames(inputVideo)
    Step3HDRFramesToVideos(inputVideo)
end

Step1MovieToInterpolatedFrames.m

function Step1MovieToInterpolatedFrames(INPUTVIDEO,EVDIFF)
    mkdir(pwd,'frames');

    % Grab the first and second frame and guess which is the light and dark
    % frame based upon the average value.  THis is crude, but seems to work
    % reasonably well.
    testFrame1 = read(INPUTVIDEO,1);
    testFrame2 = read(INPUTVIDEO,2);
    if mean(testFrame1(:)) < mean(testFrame2(:))
        DARKFRAMEFIRST = true
    else
        DARKFRAMEFIRST = false
    end
    clear testFrame1 testFrame2

    % Loop through the frames, export the light and dark frames
    % Discard the first and last pair of frames because we will need those
    % for interpolation
    lastFrame = floor(INPUTVIDEO.NumberOfFrames/2)*2-2;
    if DARKFRAMEFIRST
        frames = 2:2:lastFrame;
    else
        frames = 1:2:lastFrame-1;
    end
    for frame = frames
        fprintf('LIGHT - %03.2f%%n',frame/lastFrame*100)

        imgLight = read(INPUTVIDEO,frame);
        imgLightI = imfuse(read(INPUTVIDEO,frame),...
                           read(INPUTVIDEO,frame+2),'blend');

        % Real frame
        filename = fullfile(pwd,'frames',sprintf('frame%06uL.jpg',frame));
        imwrite(imgLight,filename,'Quality',100);
        % We are assuming the dark frame was captured at ISO 100
        system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="1.0" "' filename '"']);

        % Interpolated frame
        filename = fullfile(pwd,'frames',sprintf('frame%06uL.jpg',frame+1));
        imwrite(imgLightI,filename,'Quality',100);
        % We are assuming the dark frame was captured at ISO 100
        system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="1.0" "' filename '"']);
    end

    if DARKFRAMEFIRST
        frames = 1:2:lastFrame-1;
    else
        frames = 2:2:lastFrame;
    end
    for frame = frames
        fprintf('DARK - %03.2f%%n',frame/lastFrame*100)

        imgDark = read(INPUTVIDEO,frame);
        imgDarkI = imfuse(read(INPUTVIDEO,frame),...
                           read(INPUTVIDEO,frame+2),'blend');

        % Real frame
        filename = fullfile(pwd,'frames',sprintf('frame%06uD.jpg',frame));
        imwrite(imgDark,filename,'Quality',100);
        % The light frame is assumed to be relative to a dark frame with
        % ISO 100. The apeture values writtenwith exiftool have been
        % calculated from here: https://en.wikipedia.org/wiki/Exposure_value
        if (EVDIFF == 1)        % ISO 100 : ISO 200
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="1.4" "' filename '"']);
        elseif (EVDIFF == 2)    % ISO 100 : ISO 400
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="2.0" "' filename '"']);
        elseif (EVDIFF == 3)    % ISO 100 : ISO 800
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="2.8" "' filename '"']);
        elseif (EVDIFF == 4)    % ISO 100 : ISO 1600
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="4.0" "' filename '"']);
        elseif (EVDIFF == 5)    % ISO 100 : ISO 3200
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="5.6" "' filename '"']);
        end

        % Interpolated frame
        filename = fullfile(pwd,'frames',sprintf('frame%06uD.jpg',frame+1));
        imwrite(imgDarkI,filename,'Quality',100);
        if (EVDIFF == 1)        % ISO 100 : ISO 200
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="1.4" "' filename '"']);
        elseif (EVDIFF == 2)    % ISO 100 : ISO 400
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="2.0" "' filename '"']);
        elseif (EVDIFF == 3)    % ISO 100 : ISO 800
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="2.8" "' filename '"']);
        elseif (EVDIFF == 4)    % ISO 100 : ISO 1600
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="4.0" "' filename '"']);
        elseif (EVDIFF == 5)    % ISO 100 : ISO 3200
            system(['exiftool -overwrite_original -ShutterSpeedValue="1" -ApertureValue="5.6" "' filename '"']);
        end
    end
end

Step2FramesToHDRFrames.m

function Step2FramesToHDRFrames(INPUTVIDEO)
    mkdir(pwd,'framesHDR');
    mkdir(pwd,'framesTonemapped');

    % Because of conflicting DYLD paths on Mac OS X, need to do this:
    libPath = getenv('DYLD_LIBRARY_PATH');
    framePath = getenv('DYLD_FRAMEWORK_PATH');
    setenv('DYLD_LIBRARY_PATH', '/usr/local/bin/');
    setenv('DYLD_FRAMEWORK_PATH','')

    lastFrame = floor(INPUTVIDEO.NumberOfFrames/2)*2-2;
    for ii = 2:lastFrame
        fprintf('%03.2f%%n',ii/lastFrame*100)

        system(['"/Applications/Luminance HDR 2.3.1.app/Contents/MacOS/luminance-hdr-cli" '...
            ' -s "' fullfile(pwd,'framesHDR',sprintf('framesHDR%06u.hdr',ii)) '"'...
            ' -t mantiuk08 -o "' fullfile(pwd,'framesTonemapped',sprintf('frameTonemapped%06u.jpg',ii)) '"'...
            ' "' fullfile(pwd,'frames',sprintf('frame%06uD.jpg',ii)) '"'...
        	' "' fullfile(pwd,'frames',sprintf('frame%06uL.jpg',ii)) '"']);
    end

    % Restore the DYLD paths
    setenv('DYLD_LIBRARY_PATH',libPath);
    setenv('DYLD_FRAMEWORK_PATH',framePath)
end

Step3HDRFramesToVideos.m

function Step3HDRFramesToVideos(INPUTVIDEO)
    % Open the individual output files
    outputDark = VideoWriter('videoDark');
    outputDark.FrameRate = INPUTVIDEO.FrameRate;
    open(outputDark);
    outputLight = VideoWriter('videoLight');
    outputLight.FrameRate = INPUTVIDEO.FrameRate;
    open(outputLight);
    outputTonemapped = VideoWriter('videoTonemapped');
    outputTonemapped.FrameRate = INPUTVIDEO.FrameRate;
    open(outputTonemapped);

    % Load the images, convert them to frames, and write them to the output
    % streams.
    lastFrame = floor(INPUTVIDEO.NumberOfFrames/2)*2-2;
    for ii = 2:lastFrame
        fprintf('%03.2f%%n',ii/lastFrame*100)

        frameDark = im2frame(imread(fullfile(pwd,'frames',sprintf('frame%06uD.jpg',ii))));
        frameLight = im2frame(imread(fullfile(pwd,'frames',sprintf('frame%06uL.jpg',ii))));
        frameTonemapped = im2frame(imread(fullfile(pwd,'framesTonemapped',sprintf('frameTonemapped%06u.jpg',ii))));

        writeVideo(outputDark,frameDark);
        writeVideo(outputLight,frameLight);
        writeVideo(outputTonemapped,frameTonemapped);
    end

    close(outputDark);
    close(outputLight);
    close(outputTonemapped);
end