Abstract: 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.

Abstract: A system for enhancing an input image including receiving an input image and filtering the input image with a plurality of non-linear smoothing filters providing a respective plurality of filtered outputs. The system processes a plurality of the filtered outputs with respect to at least one of another of the filtered outputs and the input image to determine a plurality of detail layers. The system filters the plurality of detail layers with a plurality of non-linear smoothing filters providing a respective plurality of smoothed layers. The system adjusts the plurality of smoothed layers in such a manner that regions closer to an edge are enhanced to a lesser extent than regions farther from an edge and combining the adjusted the smoothed layers to provide an enhanced output image.

Abstract: The invention relates to a method of encoding an image divided into non-overlapping macroblocks themselves divided into non-overlapping blocks of N by N pixels into a binary stream. It comprises the steps of: —transforming each of the block into a transformed block of coefficients comprising one low frequency coefficient and N2-1 coefficients, called high frequency coefficients, of higher frequencies than the low frequency; —quantizing each coefficient of each of the transformed blocks with a quantizing parameter; —encoding the quantized coefficients into a binary stream. According to the invention, the low frequency coefficients of the transformed blocks are quantized with a same quantizing parameter, called first quantizing parameter.