Spatiotemporal metrics for rate distortion optimization

摘要

Spatial and temporal metrics are computed for a picture or regions within a picture to determine the impact of coding and quantization on the quality of an encoded picture. Prediction mode decisions and quantization optimization algorithms are used to create a compressed bit stream that minimizes coding artifacts. Pre-processing techniques are also used to suppress coding artifacts that reduce picture quality.

主权项

1. A method for reducing artifacts in coded pictures comprising:
computing one or more sets of metrics for a picture, wherein each set of metrics are computed based on applying one or more different coding methods; selecting one or more coding methods from the applied one or more different coding methods, wherein selection of the one or more coding methods is based on the computed one or more sets of metrics; coding the picture with the selected one or more coding methods; creating a database of spatio-temporal statistics and coding parameters that result in image artifacts and wherein selecting one or more coding methods based on the computed metrics comprises: selecting coding parameters for the picture; determining if the coding parameters cause image artifacts by accessing the database; and if the coding parameters do not cause image artifacts, coding the picture with the selected coding parameters; and if the coding parameters cause image artifacts, pre-filtering the picture and coding the pre-filtered picture with the selected coding parameters.