B. P. Lathi, Zhi Ding - Modern Digital and Analog Communication Systems-Oxford University Press (2009)

6.8 Vocoders and Video Compression 307
TABLE 6.2
8 x 8 Pixel Block Residual
158 158 158 163 161 161 162 162
157 157 157 162 163 161 162 162
157 157 157 160 161 161 161 161
155 155 155 162 162 161 160 159
m 159 159 159 160 160 162 161 159
156 156 156 158 163 160 155 150
156 156 156 159 156 153 151 144
155 155 155 155 153 149 144 139
n
TABLE 6.3
Transformed 8 x 8 Pixel Block Residual DCT Coefficients
1259.6 1.0 -12.1 5.2 2.1 1.7 -2.7 -1.3
22.6 -17.5 6.2 -3.2 -0.1 -0.4 -1.2
-10.9 9.3 -1.6 -1.5 0.2 0.9 -0.6 0.1
7.1 -1.9 -0.2 1.5 -0.9 -0.1 0.0 0.3
k -0.6 0.8 1.5 -1.6 -0.1 0.7 0.6 -1.3
-1.8 -0.2 -1.6 -0.3 0.8 1.5 -1.0 -1.0
-1.3 0.4 -0.3 1.5 -0.5 -1.7 1.1 0.8
2.6 1.6 3.8 -1.8 -1.9 1.2 0.6 -0.4
2.9
TABLE 6.4
Normalized and Quantized
Residual DCT Coefficients
21 0 -1 0 0 0 0 0
2 -1 0 0 0 0 0 0
-1 0 0 0 0 0 0
k 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0
jn
obtain Table 6.4. Normalization is accomplished by a dynamic matrix of multiplicative values,
which are applied element by element to the transformed matrix. The normalized matrix of
Table 6.4 is the block information transmitted to the decoder. The denormalized matrix pictured
in Table 6.5 and the reconstructed (inverse-transformed) residual in Table 6.6 are determined
by the decoder. The transformation proceeds in a zigzag pattern, as illustrated in Fig. 6.37.
MPEG approaches the motion estimation and compensation to remove temporal (frame-toframe)
redundancy in a unique way. MPEG uses three types of frame, the intraframe or I-frame
(sometimes called the independently coded or intracoded frame), the predicted (predictive) or