P.  Sridevi, J.  Suguna, 
    An Efficient Encryption-then-Compression System Using Asymmetric Numeral Method,
    International Journal of System Signal Control and Engineering Application,
    Volume 13,Issue 5,
    2020,
    Pages 167-174,
    ISSN 1997-5422,
    ijssceapp.2020.167.174,
    (https://makhillpublications.co/view-article.php?doi=ijssceapp.2020.167.174)
    Abstract: Image compression is an important task in the
field of image processing and it is an essential process in
digital world to reduce the memory for storage and
processing of the images. Many practical applications
need compression and security. Encryption is a security
control and widely used in many computer applications to
provide protection for data. The images are encrypted
before compression to give high level security and drawn
much attention in several applications like data
transferring, medical, navy and military operations. This
paper has proposed an efficient image Encryption and
Then Compression system (ETC) using Asymmetric
Numeral Method (ANM) for compressing the images. The
proposed ANM coder is compared with the existing
Huffman and Arithmetic coder. The comparative analysis
will be carried out for different size of images and results
are illustrated that the proposed system is efficient in
terms of compression ratio (Bits per Pixel) and
computation time.
    Keywords: Image encryption;lossless compression;security;asymmetric numerical method;prediction error clustering