Image data compressing and decompressing methods and display driving device using the same

A display driving device comprising:

• an encoder configured to receive input image data and to output compressed data using a selected binary or differential pulse code modulation (DPCM) encoding scheme, wherein the encoder comprises:
• a macro block generator configured to generate macro blocks according to a PenTile® coding matrix from the input image data, the macro blocks having a pixel structure where one pixel is formed of one red (R) sub-pixel formed as a 2×2 macro block having four R sub-pixel values, two green (G) sub-pixels formed as a 4×2 macro block having eight G sub-pixel values, and one blue (B) sub-pixel formed as a 2×2 macro block having four B sub-pixel values;
• a first set of units configured to compress the macro blocks using the binary encoding scheme to produce binary compression data, then decompress the binary compression data, and then calculate a first error with respect to the input image data;
• a second set of units configured to compress the macro blocks using the DPCM encoding scheme to produce DPCM compression data, then decompress the DPCM compression data, and then calculate a second error with respect to the input image data;
• and
• a mode selection unit configured to output one of the binary compression data and the DPCM compression data as the output compressed data based on the lesser of the first and second errors;
• a decoder configured to decompress the output compressed data using a decoding scheme corresponding to the selected encoding scheme to form decompressed data;
• and
• a source driver configured to drive source lines coupled to a display panel based on the decompressed data.