does the colour map of a gray scale image change after dct compression?if so, then please provide the matlab code for restoring the colour map after compression.

i am currently working on a project on video compression.the video has been split into a series of image frames.those image frames can be joined to get back the video.however the video cannot be obtained from those images after performing dct compression on those image frames.while doing so i am getting an error regarding colormap. can you please suggest a proper matlab code by the help of which these series of dct compressed images can be joined to form a video? thank you.

Answer 1

[Walter Roberson]

What error are you getting?

DCT does not change the colormap.You do, however, need to be careful about whether you are using uint8 or double precision numbers.

[BIJOYETA]

then can you please provide me with a matlab code for joining a series of dct compressed images into a video.

[Walter Roberson]

See the example about AVI from animation at http://www.mathworks.com/help/matlab/ref/videowriterclass.html

Note that what you would be joining is the reconstructed images. If you are trying to effectively do the compression yourself, then if you want other programs to be able to read the movie then you will need to attend to all the details of creating the movie file.