Extracting Frames and resizing each frame

Hy, i convert YUV video file to frames but now i want to change size of every frames , how can i do that?

My code is:

clc; clear; close all;
VideoSequence = 'sampleQCIF.yuv';
width = 176;
height = 144;
nframes = 300;
[Y,U,V] = yuvRead(VideoSequence, width, height, nframes);
figure;
c = 0;  % counter
for iFrame = 1:10
    c = c + 1;
   subplot(4,5,c), 
imshow(Y(:,:,iFrame));
title(['frame #', num2str(iFrame)]);
end

[Walter Roberson]

imresize

[Iqra Saleem]

I also tried imresize but again blank figure appers in MATLAB without showing any image.

Actually when i convert "akiyo.yuv" into frames. the dimension of those frames was 1x1 and i am unable to open those frames thats why i want to change dimension .

I am using imresize but again same problem, blank fig appears.

[Walter Roberson]

when you see 1x1 dimension what is class() of that variable ?

[Iqra Saleem]

i already convert YUV video to frames but unable to open in laptop. any solution?

[Iqra Saleem]

Name Size Bytes Class Attributes

RGB 1x1 1 uint8

columns 1x1 8 double

grayImage 1x1 1 uint8

rows 1x1 8 double

This is about class.

[Iqra Saleem]

sorry, my problem is different.

I attached original Matlab code and also output.

This code extract frames from YUV video precisley, but when i save those frames in laptop folder,they are not opening.

kinfly check my attach code and output.

Answer 1

[KALYAN ACHARJYA]

Frames are images use the following, read here imresize

frame_resize=imresize(frame_names,scaling_value)

For multiple frames, you can call those and do the same. Also similar question answer is available, please look here, still unable to solve it, let me know.

[Iqra Saleem]

I extract YUV video and frames dimension is 1x1. When i try resize image again blank figure appears in Matlab? Please, tell me solution.

[Iqra Saleem]

sorry, my problem is different.

I attached original Matlab code and also output.

This code extract frames from YUV video precisley, but when i save those frames in laptop folder,they are not opening.

kinfly check my attach code and output

[Walter Roberson]

You imwrite(iFrame) but iFrame is just your loop counter.

Please show size(Y), class(Y), min(Y(:)), max(Y(:))

[Iqra Saleem]

I am attaching also main function of YUV read, Kindly check.

This code display frames in matlab figure properly but when i save this and want to open in laptop, so not opening, and frames dimension is also 1 cross 1.

[Walter Roberson]

You should be imwrite(Y(:,:,iFrame), ....) not imwrite(iFrame, ...)

[Iqra Saleem]

when i try to run the code according to your comments then this error occurs, check the attachment

[Walter Roberson]

Somewhere in your yuvRead.m file, on a line before the "function" line, you have an executable line. That executable line must be removed or commented out.

[Iqra Saleem]

I am attaching yuvRead.m file. Kindly check it our and tell me where the exectuable line is.

[Walter Roberson]

get rid of the clear and close statements .

The only time you should ever have "clear all" is as part of a script that is intended to reset matlab to prepare for new work . In any situation in which do not intend to effectively quit and reenter matlab then you should not have a "clear all"

[Iqra Saleem]

i removed clear and close statements, but again the problem arise.

Now i attach the images which are shown in MATLAB and images which are not opening in matlab folder. If you see this you can easily understand.

[Walter Roberson]

as I told you 9 hourss ago you need to imwrite Y(:,:,iFrame) not iFrame. Your iFrame variable is your image counter not the content of that image .

[Iqra Saleem]

yes, i do the same thing as you said, but again error comes : unable to determine the file format"

check attachments.

[Walter Roberson]

That error message does not correspond to the code you show.

[Iqra Saleem]

oh sorry, now again check attachments.

[Walter Roberson]

Why did you remove the basefilename / fullfile code ? You are now specifying the name of a folder as the only output location. MATLAB will not be able to automatically figure out what file name to output to by guessing that you want to use the same output file name as the last file you input: you need to tell it the output file name.

I am not going to bother to type in the repaired code for you by reading your code off of your image. If you continue to have problems with this, post your code as code.

Answer 2

[kousar majeed]

how can i extract the frame and save like 1-1.jpg in the folder with the name frame folder

[Walter Roberson]

projectdir = 'directory_containing_the_videos';
outdir = 'directory_to_receive_frames';
dinfo = dir( fullfile(projectdir, '*.avi'));
videonames = fullfile(projectdir, {dinfo.name});
numvideo = length(videonames);

for vidx = 1 : numvideo
    thisfile = videonames{vidx};
    vidobj = VideoReader(thisfile);
    fidx = 0;
    while hasFrame(vidobj)
        fidx = fidx + 1;
        vidFrame = readFrame(vidObj);
        outname = fullfile(outdir, sprintf('%d-%d.jpg', vidx, fidx));
        imwrite(vidFrame, outname);
    end
    clear vidObj
end

[kousar majeed]

vidobj = VideoReader(thisfile);

giving me error in this line

[kousar majeed]

clc;

close all;

clear all;

% assigning the name of sample avi file to a variable

filename = 'Chili.avi.mp4';

%reading a video file

mov = VideoReader(filename);

% Defining Output folder as 'Frames'

opFolder = fullfile(cd, 'Frames');

%if not existing

if ~exist(opFolder, 'dir')

%make directory & execute as indicated in opfolder variable

mkdir(opFolder);

end

%getting no of frames

numFrames = mov.NumberOfFrames;

%setting current status of number of frames written to zero

numFramesWritten = 0;

%for loop to traverse & process from frame '1' to 'last' frames

for t = 1 : numFrames

currFrame = read(mov, t); %reading individual frames

opBaseFileName = sprintf('%3.3d.png', t);

opFullFileName = fullfile(opFolder, opBaseFileName);

imwrite(currFrame, opFullFileName, 'png'); %saving as 'png' file

%indicating the current progress of the file/frame written

progIndication = sprintf('Wrote frame %4d of %d.', t, numFrames);

disp(progIndication);

numFramesWritten = numFramesWritten + 1;

end %end of 'for' loop

progIndication = sprintf('Wrote %d frames to folder "%s"',numFramesWritten, opFolder);

disp(progIndication);

%End of the code

% make another folder with the name of Faces

mkdir Faces

===== upto here i run the video and it save in folder of frame. create another folder with the name of faces.now how can i extract the face using move command to load from frame folder and extract the face and save it into face folder=============