B_gcpSelection.m

%% B_gcpSelection
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% This function initializes the GCP structure for a given camera.  The user
% will load a distorted image, click on GCPS, and the function will save
% the distorted UVd coordinates and image metadata for a given camera.

% How to use clicking mechanism: The user can zoom and move the image how
% they please and then hit 'Enter' to begin clicking mode. A left click
% will select a point, a right click will delete the nearest point to the
% click. After a left click, the user will be asked to enter a GCP number
% to identify the GCP in the command window. The user can then zoom again
% until hitting enter to select the next point. To end the collection, hit
% enter to enter clicking mode (the cross hairs) and click below the image
% where it says 'Click Here to End Collection.'  Be sure to be zoomed out
% completely when ending a collection. The user can click GCPs in any order
% they would like.


%  Input:
% Input is entered by user into the script in Sections 1 and 2. Users will
% then enter information by clicking GCPs and entering an identifying
% number in the command window.

%  Output:
%  A .mat file saved as directory/filename as specified by the user.
%  'gcpUVdInitial' will be appended to the name. Will contain gcp
%  structure.

%  Required CIRN Functions:
%  None

%  Required MATLAB Toolboxes:
%  None

% This function is to be run second in the progression for each camera in a
% multi-camera fixed station or UAS flight (or if a recording mode was
% changed midflight). GCP calibration should occur any time a camera has
% moved for a fixed station, the first frame in a new UAS collect, or
% intrinsics have changed.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%


%% Housekeeping
close all
clear all

% User should make sure that X_CoreFunctions and subfolders are made active
% in their MATLAB path. Below is the standard location for demo, user will
% need to change if X_CoreFunctions is moved and/or the current script.
addpath(genpath('./X_CoreFunctions/'))





%% Section 1: User Input: Saving Information

%  Enter the filename of the gcp .mat file that will be saved as. Name
%  should be descriptive of the camera/recording mode as well as GCP
%  deployment.
oname='uasDemo';

%  Enter the directory where the mat file will be saved.
odir= './X_UASDemoData/extrinsicsIntrinsics/InitialValues';





%% Section 2: User Input: GCP Image
%  Enter the filepath of the saved image for clicking. For UAS, this should
%  be the first image of the collect.For fixed station, it should be any
%  frame where GCPs are visible.
imagePath= './X_UASDemoData/collectionData/uasDemo_2Hz/uasDemo_1443742140000.tif';





%% Section 4: Clicking and Saving GCPS:

if isempty(imagePath)==0
    
    % Display Image
    f1=figure;
    
    I=imread(imagePath);
    [r c t]=size(I);
    
    imagesc(1:c,1:r,I)
    axis equal
    xlim([0 c])
    ylim([0 r])
    xlabel({ 'Ud';'Click Here in Cross-Hair Mode To End Collection '})
    ylabel('Vd')
    hold on
    
    % Clicking Mechanism
    x=1;
    y=1;
    button=1;
    UVclick=[];
    
    while x<=c & y<=r % Clicking figure bottom will end clicking opportunity
        
        % Allow User To Zoom
        title('Zoom axes as Needed. Press Enter to Initiate Click')
        pause
        
        % Allow User to Click
        title('Left Click to Save. Right Click to Delete')
        [x,y,button] = ginput(1);
        
        
        % If a left click, ask user for number, store, and display
        if button==1  & (x<=c & y<=r)
            
            % Plot GCP in Image
            plot(x,y,'ro','markersize',10,'linewidth',3)
            
            title('Enter GCP Number in Command Window')
            
            % User Input for Number
            num=input('Enter GCP Number:');
            
            % Store Values
            UVclick=cat(1,UVclick, [num x y]);
            
            % Display GCP Number In Image
            text(x+30,y,num2str(num),'color','r','fontweight','bold','fontsize',15)
            
            % Display Values
            disp(['GCP ' num2str(num) ' [U V]= [' num2str(x) ' ' num2str(y) ']'])
            disp(' ')
            figure(f1)
            zoom out
        end
        
        % If a right click, program will delete nearest point, mark UVClick
        % Entry as unusable with value -99.
        if button==3 & (x<=c & y<=r)
            % Find Nearest Marker
            Idx = knnsearch(UVclick(:,2:3),[x y]);
            
            % Turn the visual display off.
            N=length(UVclick(:,1,1))*2+1; % Total Figure Children (Image+ 1 Text + 1 Marker for each Click)
            f1.Children(1).Children(N-(Idx*2)).Visible='off';   % Turn off Text
            f1.Children(1).Children(N-(Idx*2-1)).Visible='off'; % Turn off Marker
            
            %Display Deleted GCP
            disp(['Deleted GCP ' num2str(UVclick(Idx,1))]);
            
            % Set UVclick GCP number to Unusable Value
            UVclick(Idx,1)=-99;
            zoom out
        end
        
        
        
    end
    
    % Filter out values that were to be deleted
    IND=find(UVclick(:,1) ~= -99);
    UVsave=UVclick(IND,:);
    
    % Sort so GCP Numbers are in order
    [ia ic]=sort(UVsave(:,1));
    UVsave(:,:)=UVsave(ic,:);
    
    % Place in GCP Format
    for k=1:length(UVsave(:,1))
        gcp(k).UVd=UVsave(k,2:3);
        gcp(k).num=UVsave(k,1);
    end
    
    
end





%% Section 5: Display Results

close all

disp(['GCPs Entered for ' oname ':'])
disp(' ')

for k=1:length(gcp)
    disp(['gcp(' num2str(k) ').num = ' num2str(gcp(k).num(1)) ] )
    disp(['gcp(' num2str(k) ').UVd = [' num2str(gcp(k).UVd(1)) ' ' num2str(gcp(k).UVd(2)) ']'])
end





%% Section 6: Save File

% Incorporate imagePath in structure
for k=1:length(gcp)
    if isempty(imagePath)==0
        gcp(k).imagePath=imagePath;
    else
        gcp(k).imagePath=imagePath_noclick;
    end
end

% Save Results
save([odir '/' oname '_gcpUVdInitial' ],'gcp')