I want to compute the image quality metric VIF with MATLAB. Therefore I downloaded vifp_mscale.m. Now I could use the function vif = vifvec(img1, img2). But I have two directories (including subdirectories) where I have a bunch of images. How can I loop through these folders and compare the images properly?
Use dir:
ImageFolder1 = dir([pwd '/subfolder1/*.png']) % Or whatever file extension
ImageFolder2 = dir([pwd '/subfolder2/*.png'])
Now you can loop over the contents of the structures ImageFolder1 and ImageFolder2.
Related
I have about 300 files I would like to access and import in Matlab, all these files are inside 300 folders.
The first file lie in the directory users/matt/Documents/folder_1 with the filename line.csv the 2nd file lie in users/matt/Documents/folder_2 with filename line.csv
So I would like to import the data from the 300 line.csv files in Matlab so I can take the average value. Is this possible? I am using mac osx btw.
I know what do with the .csv file, but I have no clue how to access them efficiently.
This should work: All we are doing is generating the string for every file path using sprintf and the loop index i, and then reading the csv file using csvread and storing the data in a cell array.
for i = 1:300 % Loop 300 times.
% Full path pointing to the csv file.
file_path = sprintf('users/matt/Documents/folder_%d/line.csv', i);
% Read data from csv and store it in a cell array.
data{i} = csvread(file_path);
end
% Do your computations here.
% ...
Remember to replace the 300 by the actual number of folders that you have.
I'm using Photoshop script. I get files from folders. My problem is that when I get the files and place them in an array the array contains hidden files that are in the folder for example ".DS_Store". I can get around this by using:
if (folders[i] != "~/Downloads/start/.DS_Store"){}
But I would like to use something better as I sometimes look in lots of folders and don't know the "~/Downloads/start/" part.
I tried to use indexOf but Photoshop script does not allow indexOf. Does anybody know of a way to check if ".DS_Store" is in the string "~/Downloads/start/.DS_Store" that works in Photoshop script?
I see this answer but I don't know how to use it to test: Photoshop script to ignore .ds_store
For anyone else looking for a solution to this problem, rather than explicitly trying to skip hidden files like .DS_Store, you can use the Folder Object's getFiles() method and pass an expression to build an array of file types you actually want to open. A simple way to use this method is as follows:
// this expression will match strings that end with .jpg, .tif, or .psd and ignore the case
var fileTypes = new RegExp(/\.(jpg|tif|psd)$/i);
// declare our path
var myFolder = new Folder("~/Downloads/start/");
// create array of files utilizing the expression to filter file types
var myFiles = myFolder.getFiles(fileTypes);
// loop through all the files in our array and do something
for (i = 0; i < myFiles.length; i++) {
var fileToOpen = myFiles[i];
open(fileToOpen);
// do stuff...
}
For anybody looking I used the Polyfill found here:
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/indexOf
indexOf() was added to the ECMA-262 standard in the 5th edition; as
such it may not be present in all browsers. You can work around this
by utilizing the following code at the beginning of your scripts. This
will allow you to use indexOf() when there is still no native support.
This algorithm matches the one specified in ECMA-262, 5th edition,
assuming TypeError and Math.abs() have their original values.
I know that it is possible to load all files of type .gif by using:
files = dir('C:\myfolder\*.gif');
However, my problem is that I want to load all files of type .gif and .jpg. What would be a good way of doing this?
You can simply search for both .gif and .jpg files then load and process the images one by one.
Just invoke dir twice - one for each type of image and store the results in two separate structures. Next, concatenate all of the file names to one structure, then go ahead and do your processing for all of the images.
Something like this:
%// Specify the folder where your images are stored
folder = fullfile('path', 'to', 'your', 'folder');
%// Specify search pattern for JPEG and GIF files
jpgFileFolder = fullfile(folder, '*.jpg');
gifFileFolder = fullfile(folder, '*.gif');
%// Invoke dir for both types of images
d1 = dir(jpgFileFolder);
d2 = dir(gifFileFolder);
%// Concatenate both dir structures together into a single structure
d = [d1; d2];
%// For each image we have...
for idx = 1 : numel(d)
%// Get full path to file
f = fullfile(folder, d(idx).name);
%// Read in the image
im = imread(f);
%// Do something with this image
%//...
%//...
end
fullfile allows you to create a directory string that is OS independent. Simply take each subdirectory that is part of your string and place them as separate string arguments into fullfile and it should work fine.
I have a folder which contains images (100) from the experiment that I did. I also have another folder which contains the background images (100 also) from the detector.
I have written a code that does something like this:
% Define images directory
% Define detector bg directory
% Loop over each frame and do some processing
for a=1:length(image directory)
%read files from directory
bg_corrected_image = frame#-bg_image# % # begins with 1
n=size(image directory)
new_images=zeros(n)
% Now sort through each pixel in bg_corrected image and assign value according to a criterion
for ii=1:size(bg_corrected_image,1)
jj=1:size(bg_corrected_image,2)
pixel=bg_corrected_image(ii,jj);
if pixel>500
pix_mod=0;
elseif pixel<30
pix_mod=0;
else
pix_mod=pixel;
end
new_image(ii,jj)=pix_mod;
end
******************* CODE TO SAVE IMAGE AND NOT OVERWRITE AFTER EACH
ITERATION OF LOOP?
end
What I want to do now is to save each image(frame) after it had gone through the pixel sorting regimen so that I can just sum them all after the loop has ended. I am not too sure what is the best way to do it? I think what I need to do is to create a cell array which saves a "new_image" after each iteration and the code for that should go where I put asteriks. Please note I don't want to save images earlier in my code. Any help much appreciated.
Maybe something like the below - load in all your images to a 3D matrix "imagestack", then process them all, then output them all. Note the vectorization on the pixel replacement here will be much faster than your for-loop iteration over the pixels.
IMAGECOUNT=100;
FILEPATH_IN='images/input/%d.jpg';
FILEPATH_OUT='images/output/%d.jpg';
I=imread(sprintf(FILEPATH,1));
[hei wid]=size(I);
imagestack=zeros(hei,wid,100);
for n=1:IMAGECOUNT
imagestack(:,:,n)=imread(sprintf(FILEPATH_IN,n));
end
imagestack(imagestack>500)=0;
imagestack(imagestack<30)=0;
for n=1:IMAGECOUNT
imwrite(imagestack(:,:,n),sprintf(FILEPATH_OUT,n));
end
I have a folder of jpg files and I want to make them into a movie. I am using this script:
% Create video out of list of jpgs
clear
clc
% Folder with all the image files you want to create a movie from, choose this folder using:
ImagesFolder = uigetdir;
% Verify that all the images are in the correct time order, this could be useful if you were using any kind of time lapse photography. We can do that by using dir to map our images and create a structure with information on each file.
jpegFiles = dir(strcat(ImagesFolder,'\*.jpg'));
% Sort by date from the datenum information.
S = [jpegFiles(:).datenum];
[S,S] = sort(S);
jpegFilesS = jpegFiles(S);
% The sub-structures within jpegFilesS is now sorted in ascending time order.
% Notice that datenum is a serial date number, for example, if you would like to get the time difference in hours between two images you need to subtract their datenum values and multiply by 1440.
% Create a VideoWriter object, in order to write video data to an .avi file using a jpeg compression.
VideoFile = strcat(ImagesFolder,'\MyVideo');
writerObj = VideoWriter(VideoFile);
% Define the video frames per second speed (fps)
fps = 1;
writerObj.FrameRate = fps;
% Open file for writing video data
open(writerObj);
% Running over all the files, converting them to movie frames using im2frame and writing the video data to file using writeVideo
for t = 1:length(jpegFilesS)
Frame = imread(strcat(ImagesFolder,'\',jpegFilesS(t).name));
writeVideo(writerObj,im2frame(Frame));
end
% Close the file after writing the video data
close(writerObj);
(Courtesy of http://imageprocessingblog.com/how-to-create-a-video-from-image-files/)
But it gives me this error:
Warning: No video frames were written to this file. The file may be invalid.
> In VideoWriter.VideoWriter>VideoWriter.close at 289
In Movie_jpgCompilation at 37
I'm sure my jpg files are fine, and they are in the folder I specify. What is the problem?
(This is my first post ever, so I hope it helps).
If you're on Linux, don't the backslashes need to be forward slashes? When I ran it on my Mac, my jpegFiles was an empty Struct. When I changed them around it worked:
% Create video out of list of jpgs
clear
clc
% Folder with all the image files you want to create a movie from, choose this folder using:
ImagesFolder = uigetdir;
% Verify that all the images are in the correct time order, this could be useful if you were using any kind of time lapse photography. We can do that by using dir to map our images and create a structure with information on each file.
jpegFiles = dir(strcat(ImagesFolder,'/*.jpg'));
% Sort by date from the datenum information.
S = [jpegFiles(:).datenum];
[S,S] = sort(S);
jpegFilesS = jpegFiles(S);
% The sub-structures within jpegFilesS is now sorted in ascending time order.
% Notice that datenum is a serial date number, for example, if you would like to get the time difference in hours between two images you need to subtract their datenum values and multiply by 1440.
% Create a VideoWriter object, in order to write video data to an .avi file using a jpeg compression.
VideoFile = strcat(ImagesFolder,'/MyVideo.avi');
writerObj = VideoWriter(VideoFile);
% Define the video frames per second speed (fps)
fps = 1;
writerObj.FrameRate = fps;
% Open file for writing video data
open(writerObj);
% Running over all the files, converting them to movie frames using im2frame and writing the video data to file using writeVideo
for t = 1:length(jpegFilesS)
Frame = imread(strcat(ImagesFolder,'/',jpegFilesS(t).name));
writeVideo(writerObj,im2frame(Frame));
end
% Close the file after writing the video data
close(writerObj);
Edit: You can also use filesep so that the file separator is OS-specific. http://www.mathworks.com/help/matlab/ref/filesep.html
It would be simpler to use Windows Movie Maker [windows] or iMovie [mac]. For your purposes though you should use PowerPoint.