34 results about "Rate–distortion theory" patented technology

Transform based distortion cost estimation, which may be used to calculate a rate distortion cost associated with a mode for encoding a macroblock, is described. In one embodiment of the invention, a distortion value for a particular mode is estimated within the transform domain, which allows for the elimination of both inverse transformation and inverse motion functions in this calculation. A spatial domain residual of an encoding mode is estimated by identifying a difference, within the transform domain, between a motion compensated prediction residual of a macroblock and its corresponding reconstructed signal. The estimated spatial domain residual may then be used in distortion matrix computations to estimate a distortion level, within the transform domain, for an encoding mode.

The invention provides a method for quickly selecting HEVC (high-efficiency video coding) inframe coding units. Rate-distortion cost of each CU (coding unit), obtained by absolute error and SAD (sum of absolute difference) approximately, is related to non-uniformized gradient histogram of each CU. The higher the similarity degree of the non-uniformized gradient histograms of two equal-scale CUs is, the more possibly equal splitflags are. The method is a method for realizing quick selection of the CUs by utilizing the template matching mode on the basis of the non-uniformized gradient histograms, and accordingly, improving coding speed of the HEVC inframe prediction method. Whether each CU is required to be split into four smaller CUs or not is judged by utilizing the non-uniformized gradient histograms as features. On the condition of meeting template matching requirements, a step of comparing rate distortion cost of codes one by one is omitted.

The invention provides a video encoding method. The video encoding method comprises respectively determining rate distortion cost of at least two kinds of encoding modes, and choosing an encoding mode according to the rate distortion cost, wherein the operation of determining the rate distortion cost comprises acquiring macro block distortion quantity according to space-time similarity measurement between an original macro block and a reconstructed macro block in a video, acquiring a Lagrange multiplier according to a relation model of an encoding rate and the macro block distortion quantity, and determining corresponding rate distortion cost of the encoding mode according to the encoding rate, the macro block distortion quantity and the Lagrange multiplier. Due to the facts that the macro block distortion quantity determined by the video encoding method conforms to visual distortion sensitivity of human eyes and the Lagrange multiplier is acquired through accurate relation model, so that the rate distortion cost determined can truly reflect whether the encoding mode is suitable for a current video frame of a video sequence or not, therefore the encoding mode suitable for the video can be determined accurately, and watching effect of the video after the encoding is used is in a good status.