Image processing chip and operation method thereof

An image processing chip coupled to an external memory, the image processing chip comprising:

• a processing circuit configured to write a data to be encoded and a command mask corresponding to the data into a memory address of the external memory;
• and
• an encoder comprising:
• a first register configured to store the memory address under control of the processing circuit;
• a second register;
• a data input circuit configured to read the command mask from the external memory according to the memory address in the first register, further read the data to be encoded from the external memory according to the memory address in the first register and write the data to be encoded into the second register when the command mask is equal to a first predetermined value;
• and
• an encoding circuit configured to perform an encoding operation according to the data to be encoded in the second register to generate an encoded data;
• wherein the encoder stores one of the encoded data and an output data derived from the encoded data in the external memory.