The non-reference method is widely useful to estimation picture quality on the decoder side. In this paper, we discuss the estimation method for spatial blur that divides the frequency zones by the absolute value of 64 coefficients with an 8-by-8 DCT and compares them. It is recognized that absolute blur estimation is possible with the decoded picture only.

DCT encoding of images leads to block artifact and mosquito noise degradations in the decoded pictures. We propose an estimation to determine the mosquito noise block and level; however, this technique lacks sufficient linearity. To improve its performance, we use the sub-divided block for edge effect suppression. The subsequent results are mostly linear with the quantization.

With DCT coding, block artifact and mosquito noise degradations appear in decoded pictures. The control of post filtering is important to reduce degradations without causing side effects. Decoding information is useful, if the filter is inside or close to the encoder; however, it is difficult to control with independent post filtering, such as in a display. In this case, control requires the estimation of the artifact from only the decoded picture. In this work, we describe an estimation method that determines the mosquito noise block and level. In this method, the ratio of spatial activity is taken between the mosquito block and the neighboring flat block. We test the proposed method using the reconstructed pictures which are coded with different quantization scales. We recognize that the results are mostly reasonable with the different quantizations.

The current state of development of the television broadcasting system of the future is described with regard to LSI development. It is no need to say that television broadcasting systems are very huge and require a large number of inexpensive LSI's. Hi-Vision broadcasting has already been started in Japan. In the United States, a digital terrestrial broadcasting system (ATV) will be standardized in the near future. On the other hand, the situation in Europe remains unclear but MPEG-2 is now in the stage of system finarizing. We also hear much about "multimedia" but the concept of multimedia broadcasting still requires a lot of time to be translated into reality. Some important current technical topics and related basic technologies are also described in this paper. They include DCT, Hybrid DCT coding, error correcting coding, coded modulation, and improvement of the MUSE system. Finally, the discussion considers the relationship between system development and VLSI technology and the importance of mutual understanding between VLSI engineers and system designers. Some possible requirements for VLSI development are also stated.