A Novel Psychovisual Threshold on Large DCT for Image Compression

Table 4

Average bit length of Huffman code of image compression using 8 × 8 JPEG compression and 256 × 256 JPEG compression using psychovisual threshold for 40 real images and 40 graphical images.

Average bit length of Huffman code	8 × 8 JPEG; compression		256 × 256 JPEG; compression
	40 real images	40 graphic images	40 real images	40 graphic images
DC luminance	5.7468	5.6722	12	12
DC chrominance Cr	2.7941	3.8663	12	12
DC chrominance Cb	3.1548	4.0730	12	12
AC luminance	2.8680	2.9653	2.3031	2.6582
AC chrominance Cr	2.0951	2.5059	1.2931	2.1450
AC chrominance Cb	2.1845	2.5158	1.3656	2.1855