The invention relates to a color indexing-based
marine radar echo image transmission method. The method includes the following steps that: echo brightness and blanking time of echo
afterglow are determined, and an echo image
color index table is established; 16-bit RGB data of each pixel of an echo image are converted into 8-bit image index data; a
data processing unit transmits two adjacent 8-bit image index data to a display terminal together; the display terminal receives the image index data, and segments the image index data into a group of high single-
byte data and a group of low single-
byte data according to double-
byte data width and performs mutual exchange on the high single-byte data and the low single-byte data, and inquires truth 16-bit RGB color values in the
color index table; the converted RGB color values are combined so as to form an echo display image which is stored in a display cache and is subjected to
display processing; and step one to step five are repeated until echo acquisition terminates. Compared with an original transmission method, with the transmission method of the invention adopted, only one half of
data transmission channel bandwidth is occupied, and transmission efficiency is improved by 100%, and
radar echo image data which are acquired with a high speed can be continuously and stably transmitted to the display terminal so as to be displayed.