How do I create a video from an image being rotated?

I am trying to create a video by combining an image that is being rotated. The code gives me an .avi file, but the image is not rotating.

FPS=24;
time=10;
theta=1;
degPerFrame=10;
movie=VideoWriter('spinspokes.avi'); %create new video file
open(movie);
for i=1:FPS*time
    B=imread('spokes.tif'); %open image file
    writeVideo(movie,B);
    pause(0.01)
    theta=theta+degPerFrame;
    B=imrotate(B,theta,'bilinear','crop'); %rotate image
end
close(movie);
implay('spinspokes.avi')

Answer 1

[Dave B]

You're reading in the image, then writing the video frame, then rotating the image. I think you intended to rotate the video before writing the video:

for i=1:FPS*time
    B=imread('spokes.tif'); %open image file
    pause(0.01)
    theta=theta+degPerFrame;
    B=imrotate(B,theta,'bilinear','crop'); %rotate image
    writeVideo(movie,B);
end

Better still, just read in the video once:

B=imread('spokes.tif'); %open image file
for i=1:FPS*time
    theta = theta + degPerFrame;
    B_rotate = imrotate(B, theta, 'bilinear', 'crop'); %rotate image
    writeVideo(movie, B_rotate);
end