JPH0779487B2 - Compressed stereoscopic image data reproduction system - Google Patents

Description

The present invention relates to a compressed stereoscopic image data reproducing system capable of reproducing a stereoscopic image.

[Prior Art] Images obtained by simultaneously capturing images of two video cameras at the positions of both eyes of a human being are alternately recorded on a recording track of an electrostatic capacity type disc, and a left-eye dedicated image and a right-eye dedicated image are recorded. By alternately playing the image of, and viewing the reproduced image alternately with the left eye and the right eye through the stereoscopic scope with a liquid crystal shutter,
A stereoscopic image reproduction system for reproducing a stereoscopic image is known. This type of stereoscopic image reproduction system reproduces a stereoscopic image using binocular parallax, but unlike the case of a planar image, it has the same capacity for recording left-eye and right-eye video signals. With a recording medium, only about half the signal of a normal video signal can be recorded, which is not suitable for long-term recording of video software.

By the way, there is a high-efficiency coding method that is in the limelight in recording a large amount of image data on a recording medium having a relatively small recording capacity. This method is a method of compressing by subtracting a prediction value predicted using data of one frame before from image data regarding pixels in an XY two-dimensional image plane and encoding the difference as prediction error data. . In general, since the prediction error data can be approximated by a Laplace distribution, in the conventional compressed image data recording / reproducing system 1 shown in FIG. 3, the quantizing circuit 3 in the encoder 2 used in the recording system is nonlinear by logarithmic compression. A quantizer circuit is used. The encoder 2 supplies the input image data to the quantization circuit 3 via a subtracter 4 that takes the difference from its predicted value. The prediction error data converted from the level value to the level number in the quantization circuit 3 is converted into an unequal-length code in the code conversion circuit 5 and recorded in the CD-ROM 6, while being transmitted via the local decoder 7. It is fed back to the subtractor 4. The local decoder 7 outputs the output of the inverse quantization circuit 8 for inverse processing of the quantization, that is, the inverse conversion of the level number into the level value, via the predictor 9 and the subtractor 4
While being fed back to the adder 10 provided on the input side of the predictor 9.

On the other hand, the decoder 12 for decoding the prediction error data read from the CD-ROM 6 is a code inverse conversion circuit for converting the prediction error data code-converted by the unequal length coding into the equal-length code by the inverse conversion. 13, an inverse quantization circuit 14 that inversely quantizes the output of the code inverse conversion circuit 13, an adder 15 and a predictor 16 that form image data from the output prediction error data of the inverse quantization circuit 14.
Consists of. The output of the inverse quantization circuit 14 is output via the adder 15 and is positively fed back to the adder 15 via the predictor 16, and the image data is reproduced by the cyclic addition of the prediction error data and its decoded output. It

[Problems to be Solved by the Invention] In the conventional compressed image data recording / reproducing system 1 described above, since the stereoscopic image data is not compressed and recorded, the left-eye dedicated image signal and the right-eye dedicated image signal are respectively subjected to predictive coding. When the prediction error data obtained by compression is recorded on the CD-ROM 6 alternately left and right, there is a problem in that proper reproduction cannot be performed if the same decoding method as that for reproducing planar image data is followed. This is because, as a result of mixed reproduction of the left-eye-only and right-eye-only image data, which originally makes sense only when reproduced independently of each other, as a result, the viewpoint cannot be localized. It was the actual situation that even with a naked eye, even when a stereoscopic scope was attached, the stereoscopic image, not even the planar image, could be viewed.

[Means for Solving Problems] The present invention solves the above problems and compresses the left-eye dedicated image signal and the right-eye dedicated image signal by predictive coding, and records prediction error data alternately on the left and right. The compressed image data recording medium and the prediction error data read from the compressed image data recording medium are divided into a left-eye dedicated image signal and a right-eye dedicated image signal by a pair of prediction circuits and alternately decoded. [Operation] The present invention reads prediction error data from a compressed image data recording medium in which a left-eye-only image signal and a right-eye-only image signal are compressed and recorded by predictive coding, and the read prediction error data is read. Is divided into a left-eye dedicated image signal and a right-eye dedicated image signal by a pair of prediction circuits in the decoder and alternately decoded to obtain a compressed image data. Perform a three-dimensional image reproduction from.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a system configuration diagram showing an embodiment of a compressed stereoscopic image data reproducing system of the present invention, and FIG. 2 is a diagram showing an example of recorded data of the CD-ROM shown in FIG.

The compressed stereoscopic image data reproduction system 21 shown in FIG. 1 compresses the left-eye dedicated image signal and the right-eye dedicated image signal by predictive coding, respectively, and records prediction error data alternately on the left and right.
It uses a CD-ROM 22 and a decoder 25 that decodes the prediction error data read from the CD-ROM 22 into a left-eye-dedicated image signal and a right-eye-dedicated image signal by a pair of prediction circuits 23 and 24 and alternately decodes them. Becomes a compressed stereoscopic image data recording medium
On the CD-ROM 22, as shown in FIG. 2, prediction error data Ln and Rn obtained by separately performing interframe predictive coding on the left-eye-dedicated image data V1 and the right-eye-dedicated image data Vr are recorded alternately on the left and right. There is. The subscript n is the frame number (1,
2 ...), and each prediction error data Ln, Rn is additionally provided with index data indicating whether the data is for the left eye or for the right eye.

By the way, the prediction circuits 23 and 24 in the decoder 252 are dedicated to the left eye and the right eye, respectively, and the predictor 28 is configured by connecting the changeover switches 26 and 27 before and after the parallel connection circuit. 29 is a decoding control circuit for controlling the predictor 28, the prediction error data Ln read from the CD-ROM 22,
The index data attached to Rn is detected, and the changeover switches 26 and 27 are controlled to be switched according to the detected index data, and a synchronization signal for interlocking the stereoscopic scope with the output image is output.

That is, the prediction error data Ln for the left eye only for the decoder 25
Is supplied, the decoding control circuit 29 switches the selector switches 26, 27 to the prediction circuit 23 side dedicated to the left eye. As a result, the prediction error data Ln dedicated to the left eye is always decoded using the prediction circuit 23 dedicated to the left eye. Also,
When the prediction error data Rn dedicated to the right eye is supplied to the decoder 25, the decoding control circuit 29 causes the changeover switches 26 and 27.
To the prediction circuit 24 side dedicated to the right eye. Therefore, the prediction error data Rn dedicated to the right eye must be the prediction circuit 24 dedicated to the right eye.
Will be decrypted using. Thus, the decoder 25
From this, image signals dedicated to the left eye and image signals dedicated to the right eye can be obtained alternately, so by viewing these left and right image signals through a stereoscope with a liquid crystal shutter, for example, a stereoscopic image using binocular parallax can be viewed. it can.

Thus, the compressed stereoscopic image data reproducing system 21
From the CD-ROM22 compressed and recorded the left-eye-only image signal and the right-eye-only image signal by predictive coding, respectively, the prediction error data Ln, Rn is read, and the read prediction error data Ln,
Since Rn is configured to be divided into a left-eye-dedicated image signal and a right-eye-dedicated image signal by the pair of prediction circuits 23 and 24 in the decoder 25 and alternately decoded, the left-eye-dedicated image is only the left-eye and the right-eye-dedicated image. By viewing with only the right eye, an image with parallax from both eyes can be viewed as one image, that is, a stereoscopic image, by utilizing the binocular parallax.

In the above embodiment, the compressed image data recording medium is not limited to the CD-ROM 22, but may be another magnetic recording medium such as a magnetic disk or a magnetic tape.

[Effects of the Invention] As described above, the present invention reads prediction error data from a compressed image data recording medium in which a left-eye-only image signal and a right-eye-only image are compressed and recorded by predictive coding, and the read prediction error data is read. Is configured so that it is divided into a left-eye image signal and a right-eye image signal by a pair of prediction circuits in the decoder and alternately decoded, so the left-eye image is viewed only by the left eye, and the right-eye image is viewed by the right eye only. As a result, an image with parallax from both eyes can be viewed as one image, that is, a stereoscopic image by utilizing the binocular parallax, which is an excellent effect.

[Brief description of drawings]

FIG. 1 is a system configuration diagram showing an embodiment of a compressed stereoscopic image data reproducing system of the present invention, FIG. 2 is a diagram showing an example of recorded data of the CD-ROM shown in FIG. 1, and FIG. FIG. 1 is a system configuration diagram showing an example of a conventional compressed image data recording / reproducing system. 21 …… Compressed stereoscopic image data playback system, 22 …… CD-RO
M, 23,24 ... Predictor, 25 ... Decoder, 26,27 ... Changeover switch, 28 ... Predictor, 29 ... Decoding control circuit.

Claims (1)

[Claims] 1. A compressed image data recording medium in which a left-eye dedicated image signal and a right-eye dedicated image signal are respectively compressed by predictive coding, and prediction error data is alternately recorded on the left and right, and a prediction error read from the compressed image data recording medium. A compressed stereoscopic image data reproducing system comprising a decoder which divides data into a left-eye image signal and a right-eye image signal by a pair of prediction circuits and alternately decodes them.