| 摘要 |
A method for deterministic film grain addition, e.g. to video signals compressed in a way that the grain is lacking. The method of electronic image processing comprises: determining a first random value (Rl) corresponding to a first horizontal pixel position (hi) in a vertically positioned first horizontal line (Ll) of an inputted picture (PIC) ; and-deriving a resultant value (R) for a second horizontal pixel position (h2) in a vertically positioned second horizontal line (L2), the resultant value depending on the first random value and a second random value (R2) corresponding to the second horizontal pixel position in the second horizontal line, random values for horizontally neighboring pixel positions being determined by successive outputs of a single random generator initialized with a seed, wherein the first random value is determined with a first random generator (nl) initialized with a first seed (Sl) for a firstmost horizontal pixel position in the first horizontal line (fl), and the second random value is determined with a second random generator (n2) running in parallel with the first random generator, and initialized with a second seed (S2) for a firstmost horizontal pixel position in the second horizontal line (f2), which second seed (S2) is substantially equal to a random value obtained by applying the first random generator (nl) for the firstmost horizontal pixel position in the second horizontal line (f2) after having consecutively been applied to all horizontal positions on a left-right-top-bottom zig-zag scan path (ZZ) being initialized with the first seed (Sl) and starting from the firstmost horizontal pixel position in the first horizontal line (fl). The advantage is lower memory requirements for deterministic film grain addition. |
