Abstract: It is known to represent a square block of an image which has a maximum horizontal or vertical extension N as N vectors each representing one column or row, and encode it using an N×N discrete cosine transform matrix. We introduce a technique which transforms an input vector, or array, representing a portion of an arbitrarily-shaped object block in which the maximum horizontal or vertical extension is at most N, by adding to it additional padding elements, to produce a vector or array which can be encoded using an N×N discrete cosine transform. The padding maximises the number of transformed elements which are zero. We propose encoding arbitrarily-shaped objects based on this padding technique.

Abstract: A data transmission system is proposed, for example for video-on-demand, internet or multimedia applications, in which a number of subscribers in a building are connected to a central server through at least in part twisted pair cables within the building. Compensation for the channel distortion caused by the use of twisted pair cables is provided by the use of pre-emphasis filters in the outgoing data lines from the server. The required coefficients for the pre-emphasis filters are established by first characterizing the distortion properties of a channel by the use of a test signal.

Abstract: It is known to represent a square block of an image which has a maximum horizontal or vertical extension N as N vectors each representing one column or row, and encode it using an N×N discrete cosine transform matrix. We introduce a technique which transforms an input vector, or array, representing a portion of an arbitrarily-shaped object block in which the maximum horizontal or vertical extension is at most N, by adding to it additional padding elements, to produce a vector or array which can be encoded using an N×N discrete cosine transform. The padding maximises the number of transformed elements which are zero. We propose encoding arbitrarily-shaped objects based on this padding technique.