Data transmission system and data transmission method thereof

A data transmission system comprising:

• an analog image frame buffer storing a plurality of image data lines generated from an image sensor as analog signals, the image data lines including a first image data line and a second image data line;
• at least a line analog to digital converter electrically connected to the analog image frame buffer and converting the image data lines from analog signals to digital signals;
• at least two line buffer memories electrically connected to the line analog converter and storing the image data lines converted into digital signals in the line buffer memories, the line buffer memories including a first line buffer memory and a second line buffer memory;
• and
• an interface electrically connected to the line buffer memories and sequentially outputting the image data lines according to instructions of a master device;
• wherein a number of the line buffer memories is larger than or equal to twice of a number of the line analog to digital converters.