The invention relates to
code rate control and discloses a
code rate control method of video coding and a
system thereof. According to code
stream output information, a channel bandwidth is predicted and an encoding rate is correspondingly adjusted so that output
delay can be well controlled under a condition that the channel bandwidth is limited and is easy to change and a
low delay application scene demand is satisfied. The method comprises the following steps that the
current channel bandwidth is predicted; according to a
current channel bandwidth prediction value, a target
code rate is distributed; according to the distributed target code rate, a code
stream size of a previous coded frame and a coding
image complexity, a corresponding quantification parameter is calculated and obtained; according to the quantification parameter, coding
processing is performed on an image to be coded, an encoding
stream is output, and the code stream size of the current coded frame and the coding
image complexity are output; a code stream output buffer area carries out output time
delay control according to the
current channel bandwidth prediction value and code stream
residence information of the code stream output buffer area.