The invention discloses a screen
video encoding and decoding method based on progressive character block compression and an encoding and decoding device thereof. The screen
video encoding and decoding method comprises the following steps: obtaining a frame in a screen video, and dividing the frame into M*N
macro blocks; dividing each
macro block into character blocks or image blocks according to the category; dividing each character block into a plurality of character compression code streams according to a main color and a non-main color; encoding the main color by an index table, and progressively encoding escape colors of the non-main color based on a
bit plane; dividing each image block into a plurality of image encoding quality
layers by using a progressive image
encoding algorithm based on
wavelet transform; transmitting the code streams to a receiving terminal according to different quality grades; and decoding and displaying the code
stream of each quality layer by the receiving terminal. According to the screen
video encoding and decoding method disclosed by the invention, in view of the limitation and defects of traditional character encoders, the progressive
character encoding technology of a plurality of quality
layers is realized, no support of special equipment is needed, and the screen video encoding and decoding method is applicable to all occasions needing to compress screen images containing characters.