Conversion of frame rate according to image data

• US 20040136686A1
• Filed: 10/24/2003
• Published: 07/15/2004
• Est. Priority Date: 11/07/2002
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kono, Masaru, Nagano, Miki, Yoshikuni, Norihiro
• Granted Patent: US 7,142,245 B2
• Time in Patent Office: Days
• US Class Current: 386/46
• CPC Class Codes: H04N 5/74 Projection arrangements for image reproduction, e.g. using eidophor
• CPC Class Codes: H04N 7/012 Conversion between an interlaced and a progressive signal for graphics images G09G2310/0229
• CPC Class Codes: H04N 7/0132 the field or frame frequency of the incoming video signal being multiplied by a positive integer, e.g. for flicker reduction

Abstract

To suppress the degradation of the image quality of movies that are played on an image display device.

A projector having a DVD playback function is configured. In case where movie data that was read out from a DVD comprises a movie film having a frame rate of 24 (fps), a frame rate conversion unit 22 converts the frame rate from 24 (fps) to the triple i.e. 72 (fps) without performing a 2 to 3 pull down telecine conversion. In addition, the driving frequency of a liquid crystal panel 32 is also switched to 72 (Hz) according to the conversion of frame rate.

Claims

1. An image display device that displays images on an image generation unit that is switchable of driving frequency, comprising:

an input unit that inputs movie data;

a detection unit that detects a frame rate of said movie data;

a decision unit that decides, based on said frame rate, whether or not a conversion of said frame rate is necessary;

a frame rate conversion unit that converts said frame rate by multiplying said frame rate by n (n is an integer that is equal to or more than two), when it was decided that the conversion of said frame rate is necessary; and

a driving frequency control unit that switch-controls a driving frequency of said image generation unit so as to synchronize it with said frame rate.

2. An image display device according to claim 1, wherein

said frame rate conversion unit converts said frame rate by repeatedly outputting an identical frame for n times.

3. An image display device according to claim 1, wherein

said frame rate conversion unit converts said frame rate by, based on successive two frames, generating and inserting (n-1) predictive frames to be inserted between said two frames.

4. An image display device according to claim 1, wherein

said input unit inputs voice data along with said movie data;

and

said image display device further comprises a transmission unit for wirelessly transmitting said voice data to a voice output device, which is separate from said image display device.

5. An image display device according to claim 4, further comprising:

a timing adjustment unit that adjusts at least one of an image generation timing of said image generation unit and a transmission timing of said transmission unit, so as to synchronize a voice output timing on the part of said voice output device and the image generation timing of said image generation unit.

6. An image display device according to claim 1, further comprising:

a readout unit that reads out said movie data from a given recording medium;

wherein said input unit inputs the movie data that was read out from said readout unit.

7. A playback device that plays back movie data that is recorded in a given recording medium, comprising:

a readout unit that reads out said movie data from said recording medium;

a detection unit that detects a frame rate of said movie data;

a decision unit that decides, based on said frame rate, whether or not a conversion of said frame rate is necessary;

a frame rate conversion unit that converts said frame rate by multiplying said frame rate by n (n is an integer that is equal to or more than two), when it was decided that the conversion of said frame rate is necessary; and

an output unit that outputs said movie data.

8. A method of controlling an image display device that comprises an image generation unit that is switchable of driving frequency, said method comprising the steps of:

(a) obtaining given movie data;

(b) detecting a frame rate of said movie data;

(c) based on said frame rate, deciding whether or not a conversion of said frame rate is necessary;

(d) when it was decided that the conversion of said frame rate is necessary, converting said frame rate by multiplying said frame rate by n (n is an integer that is equal to or more than two); and

(e) switch-controlling a driving frequency of said image generation unit so as to synchronize it with said frame rate.

9. A method of playing back movie data that is recorded in a given recording medium, comprising the steps of:

(a) reading out said movie data from said recording medium;

(b) detecting a frame rate of said movie data;

(c) based on said frame rate, deciding whether or not a conversion of said frame rate is necessary;

(d) when it was decided that the conversion of said frame rate is necessary, converting said frame rate by multiplying said frame rate by n (n is an integer that is equal to or more than two); and

(e) outputting said movie data.

10. A computer readable media recorded with a computer program for controlling an image display device that comprises an image generation unit that is switchable of driving frequency, said computer program causes a computer to implement the functions of:

obtaining given movie data;

detecting a frame rate of said movie data;

based on said frame rate, deciding whether or not a conversion of said frame rate is necessary;

when it was decided that the conversion of said frame rate is necessary, converting said frame rate by multiplying said frame rate by n (n is an integer that is equal to or more than two); and

switch-controlling a driving frequency of said image generation unit so as to synchronize it with said frame rate.

11. A computer readable media recorded with a computer program for playing back movie data that is recorded in a given recording medium, said computer program causes a computer to implement the functions of:

reading out said movie data from said recording medium;

detecting a frame rate of said movie data;

based on said frame rate, deciding whether or not a conversion of said frame rate is necessary;

when it was decided that the conversion of said frame rate is necessary, converting said frame rate by multiplying said frame rate by n (n is an integer that is equal to or more than two); and

outputting said movie data.