摘要 |
The invention relates to a video image band adjustment method and a filter arrangement. An image, composed of pixels, is subjected to at least pre-filtering in a filter (21), coding in an encoder (22) and storage in a buffer (23) for further transmission. The pre-filter (21) is arranged to generate for each image pixel a reference value, which is a function of the values of a pixel block associated with the pixel. The value filtered for the pixel by the pre-filter (21) is a function of the difference between the original pixel value and the generated reference value and the filtering threshold value. To decrease the bandwidth of the image signal bit stream, the filter arrangement further comprises adjustment means (24), arranged to change the pre-filter (21) threshold value according to the buffer (23) fill rate. |