Abstract: A method of obtaining a quantization value for macroblocks of a picture for video compression includes estimating 11, for a plurality of quantization values, a size of the picture in terms of a sum of all quantized coded coefficients. A linear relationship between a size of a macroblock and Activity of the macroblocks is assumed 12, where the Activity of the macroblock is the number of coded coefficients in the macroblock before discarding any coefficients or quantizing the remaining coefficients. The macroblocks are divided 13 into groups by their Activity level such that substantially a same number of pre-quantization coefficients are in each group. An average Activity of each group is determined 14. A quantization value for each group is determined 15 from the assumed linear relationship between a number of bits per macroblock and Activity of the macroblocks and the average Activity of the group, as imposed by a predetermined bit rate.

Abstract: A method of obtaining a quantisation value for macroblocks of a picture for video compression includes estimating 11, for a plurality of quantisation values, a size of the picture in terms of a sum of all quantised coded coefficients. A linear relationship between a size of a macroblock and Activity of the macroblocks is assumed 12, where the Activity of the macroblock is the number of coded coefficients in the macroblock before discarding any coefficients or quantising the remaining coefficients. The macroblocks are divided 13 into groups by their Activity level such that substantially a same number of pre-quantisation coefficients are in each group. An average Activity of each group is determined 14. A quantisation value for each group is determined 15 from the assumed linear relationship between a number of bits per macroblock and Activity of the macroblocks and the average Activity of the group, as imposed by a predetermined bit rate.

Abstract: An image processor arranged in operation to generate an interpolated video signal from a received video signal representative of an image. The image processor comprises an adaptable register store comprising a plurality of register elements and is coupled to a control processor which is operable to receive the video signal and to provide pixels of the received video signal, under control of the control processor to an interpolator, selected regester elements being connected to the interpolator to provide the pixels of the received video signal for interpolation, each of the register elements being arranged to store a pixel of the received video signal and each is connected to a plurality of other register elements and is configurable under control of the control processor to feed the pixel stored in the register element to one of the plurality of other register elements in accordance with a temporal reference and the interpolator being coupled to the adaptable register store.

Abstract: An image processor is arranged in operation to generate an interpolated video signal from a received video signal representative of an image. The image processor comprises an adaptable register store coupled to a control processor which is operable to receive the video signal and to provide pixels of the received video signal, under control of the control processor, to an interpolator, the interpolator being coupled to the adaptable register store and is arranged in operation to generate the interpolated video signal by interpolating the pixels provided by the adaptable register store. The control processor controls in operation the adaptable register store to provide pixels to the interpolator to interpolate parts of the image in both vertical and horizontal directions. Performing diagonal interpolation can substantially reduce ringing effects and resolution loss on diagonal edges of an image.