Patent ID: 8265165

Claim:
A method for decoding video data that is encoded by bit rate control, comprising: decoding the encoded video data; estimating picture quality estimation information including information about a bit stream byte size of a decoded video frame (SIZE), the number of 4-fragment macro blocks included in the video frame (4 MV), and the number of skip-mode macro blocks included in the video frame (SKIP); determining a picture quality of the video data based on a correlation between the picture quality estimation information and Signal-to-Noise Ratio (SNR), wherein the SNR is estimated by using the bit stream byte size of the video frame, the number of the skip-mode macro blocks in the video frame, and the number of the 4-fragment macro blocks, and the picture quality of the video data is determined based on the estimated SNR; and outputting the video data by applying a picture quality improving algorithm to the video data, if the determined picture quality is lower than a predetermined level.