What is fixed rate encoding?

Answer: Fixed rate coding: Usually fixed rate video coding algorithms are implemented by changing the quantizer step size using the buffer state. When the image details are rich, in order to ensure that the buffer does not overflow, it is necessary to increase the quantization step size and reduce the number of encoded bits, so as to ensure the constant bit rate of the output code stream. This comes at the expense of video quality. Because increasing the quantization step size will damage the high-frequency details and low-frequency background of the image, and even produce "block effect" and blurring of image details.