Dynamic Image Reproducing Method And Device

1 . A moving picture reproducing method adapted for high-speed reproduction of a moving picture file including different picture formats, comprising:

predicting, upon finding an intra-frame encoded picture to be displayed, a position of an intra-frame encoded picture to be subsequently displayed, and

starting a search for an intra-frame encoded picture to be subsequently displayed at the predicted position.

2 . A moving picture reproducing method adapted for high-speed reproduction of a moving picture file including different picture formats, comprising:

updating, upon finding an intra-frame encoded picture to be displayed, a position at which to refer to data to a data position ahead of a current position by a data distance set up according to a value given by γ/α×β;

starting a search for a next intra-frame encoded picture at the updated position at which to refer to data; and

decoding the intra-frame encoded picture found as a result of the search, where α denotes the number of frames to be displayed per a unit time, β denotes a reproduction speed ratio, γ denotes a bit rate, and α, β, and γ are real numbers.

3 . The method according to claim 2 , further comprising:

calculating the bit rate γ by dividing the size of the moving picture file to be reproduced by a reproduction time.

4 . The moving picture reproducing method according to claim 2 , further comprising:

adaptively setting up the number of frames a to be displayed per a unit time, in accordance with a search time required to search for one intra-frame encoded picture.

5 . The method according to claim 4 , wherein the search time is calculated by dividing a time elapsed since the start of reproduction by the number of intra-frame encoded pictures found hitherto.

6 . The moving picture reproducing method according to claim 2 , wherein the data distance is defined to be a value derived by multiplying γ/α×β by a constant smaller than 1.

7 . A moving picture reproducing apparatus adapted for high-speed reproduction of a moving picture file including different picture formats, comprising:

a parameter setting unit operative to set the number of frames α to be displayed per a unit time, a reproduction speed ratio β, and a bit rate γ, where α, β, and γ are real numbers;

a data distance setting unit operative to set a data distance according to a value given by γ/α×β;

an intra-frame encoded picture searching unit operative to start a search for a next intra-frame encoded picture at a search start position; and

a decoder operative to decode the intra-frame encoded picture found as a result of the search by the intra-frame encoded picture searching unit,

wherein the intra-frame encoded picture searching unit sets a data position ahead, by the data distance, of a data position of a given intra-frame encoded picture found, as a search start position to start searching for a next intra-frame encoded picture.

8 . The moving picture reproducing apparatus according to claim 7 , wherein the parameter setting unit sets the bit rate γ by dividing the size of the moving picture file to be reproduced by a reproduction time.

9 . The moving picture reproducing apparatus according to claim 7 , wherein the parameter setting unit adaptively sets up the number of frames α to be displayed per a unit time, in accordance with a search time required to search for one intra-frame encoded picture.

10 . The moving picture reproducing apparatus according to claim 9 , wherein the parameter setting unit calculates the search time by dividing a time elapsed since the start of reproduction by the number of intra-frame encoded pictures found hitherto.

11 . The moving picture reproducing apparatus according to claim 7 , wherein the parameter setting unit defines the data distance to be a value derived by multiplying γ/α×β by a constant smaller than 1.

12 . A computer program product adapted for high-speed reproduction of a moving picture file including different picture formats, comprising the modules for:

setting the number of frames α to be displayed per a unit time, a reproduction speed ratio β, and a bit rate γ, where α, β, and γ are real numbers;

setting a data distance according to γ/α×β×k, where k denotes a real number satisfying 0<k≦1;

jumping from a data position at which an intra-frame encoded picture is found to a data position ahead by the data distance;

starting a search for a next intra-frame encoded picture at the data position at the destination of the jump; and

decoding the intra-frame encoded picture found as a result of the search, wherein

at least the setting of a data distance, the jumping, the starting, and the decoding are repeatedly executed by a computer.

13 . A recording medium having embodied thereon the computer program product according to claim 12 .