Data compression method and data compression system

A data compression system and a data compression method using the same are provided. The data compression method includes acquiring original data from a memory and performs image processing and quantization on the original data to transform the original data into a quantization matrix. The data compression method then transforms the quantization matrix into a digital sequence based on a coding table and compares the data volume of the digital sequence and a target volume to generate a volume difference. The data compression method transforms the digital sequence into an inverse quantization matrix based on the volume difference and then transforms the inverse quantization matrix into a modified digital sequence based on the volume difference. The data compression method repeats the processes until the data volume of the digital sequence is substantially equal to a target volume or within an acceptable range of the target volume.