Motion image rendering systems and methods

1. A method of modifying, in a processor, an input sequence of temporal image-samples representing a moving image so as to obtain an output sequence of temporal image-samples in which the appearance of the said motion has been changed, the method comprising:

temporally interpolating said input temporal image-samples to create the said output sequence; and

introducing an intentional, periodic motion-judder component that is visible when the said output temporal image-samples are displayed;

wherein the said intentional motion-judder component is determined by a sine function.

2. A method according to claim 1 , wherein the magnitude of the motion-judder component applied to a temporal image-sample is proportional to the instantaneous value of a temporal sinewave at the intended time of display of the temporal image-sample.

3. A method according to claim 1 , wherein the frequency of the said sine function is equal to the original temporal sampling frequency of the input temporal image-samples.

4. A method according to claim 1 , further comprising motion-compensating the said temporal interpolation.

5. A method according to claim 1 , further comprising performing the said temporal interpolation by a polyphase FIR filter.

6. A method according to claim 5 , wherein at least one phase of the said polyphase FIR filter is derived from an interpolation aperture position that does not correspond to the intended display time of the respective interpolated output temporal sample created by that filter phase.

7. An apparatus for modifying an input sequence of temporal image-samples representing a moving image so as to obtain an output sequence of temporal image-samples in which the appearance of the said motion has been changed, the apparatus comprising:

a temporal interpolator configured to receive said input samples; and

a temporal phase signal generator configured to generate a temporal phase signal,

wherein the temporal interpolator serves, through interpolation of said input samples under the control of said phase signal, to create the said output sequence, and

wherein the temporal phase signal includes a periodic motion-judder component such that intentional, visible, periodic motion-judder is introduced when the said output temporal image-samples are displayed;

in which the said intentional motion-judder component is determined by a sine function.

8. An apparatus according to claim 7 , wherein the magnitude of the motion-judder component applied to a temporal image-sample is proportional to the instantaneous value of a temporal sinewave at the intended time of display of that temporal image-sample.

9. An apparatus according to claim 7 , wherein the frequency of the said sine function is equal to the original temporal sampling frequency of the input temporal image-samples.

10. An apparatus according to claim 7 , wherein the said temporal interpolation is motion-compensated.

11. An apparatus according to claim 7 , wherein the said temporal interpolation is performed by a polyphase FIR filter.

12. An apparatus according to claim 11 , wherein at least one phase of the said polyphase FIR filter is derived from an interpolation aperture position that does not correspond to the intended display time of the respective interpolated output temporal sample created by that filter phase.

13. A non-transitory computer readable medium comprising:

instructions configured to cause a programmable processor to modify an input sequence of temporal image-samples representing a moving image so as to obtain an output sequence of temporal image-samples in which the appearance of the said motion has been changed,

wherein the said input temporal image-samples are temporally interpolated to create the said output sequence and an intentional, periodic motion-judder component is introduced that is visible when the said output temporal image-samples are displayed;

wherein the said intentional motion-judder component is determined by a sine function.