Reading images in matlab

Am using a database which is gathered from 100 persons, 3 images per persons of each of 4 different activities like act,bag,norm and ice. I want to read those images from a folder but I don't understand how to read it, following is the format of those images

p1_left_act_1       to    p1_left_act_3, 
p1_left_bag_1       to    p1_left_bag_3,
p1_left_norm_1      to    p1_left_norm_3,  
p1_left_ice_1       to    p1_left_ice_3

Answer 1

[KSSV]

images = dir('.*jpg') ; % give your image extension
N = length(images) ; % total number of images
for I = 1:N    % loop for each image
    thisimage = images(I).name ;
   % do what you want
end