JP3257256B2 - Still image processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a still image processing apparatus suitable for use when displaying one screen of a moving image displayed by interlaced scanning such as a television screen as a still image.

[0002]

2. Description of the Related Art Conventionally, in order to display one screen of a moving image displayed by interlaced scanning such as a television screen as a still image, an image signal, which is an analog signal, is converted into digital data. Digital data is stored in a semiconductor memory, and a still image is displayed by sequentially reading out the stored data.

[0003]

In interlaced scanning, one image is formed by two field scans of an ODD (odd number) field and an EVEN (even number) field. However, a time difference is generated between the ODD field and the EVEN field. (About 16.7 ms in the NTSC system), for example, when displaying a moving object as shown in FIG. 4A, the image display of FIG. 4B is performed in the ODD field, and in the next EVEN field, the image is displayed from the ODD field. The image display shown in FIG. 4C after a lapse of a predetermined time is performed. When one still image is formed from the images of the ODD field and the EVEN field, the display position of the object is displayed differently as shown in FIG. 4D, so that there is a problem that the displayed image is a displaced image. Was.

Accordingly, the present invention provides a still image processing apparatus capable of obtaining a good still image irrespective of image movement.

[0005]

According to the first aspect of the present invention, there is provided a still image processing apparatus comprising: decoding means for separating a motion vector from an image data signal having a motion vector ;
The motion vector output from the means is the timing of the image data.
Axis adjustment means that sorts to correspond to
And data memory means for storing image data of continuous odd and even fields, and memory control means for controlling storage and reading of data in the data memory means,
In the memory control means, the odd and even numbers are stored in the data memory means.
Record image data for one or both fields
When reminding, sorting is performed by the time axis adjustment means
In addition to performing motion compensation on the basis of the obtained motion vector, the image data stored in the data memory means is sequentially read to form one frame of image data.

[0006]

[0007]

[Action] In the invention of claim 1, and a motion vector is separated from the image data signals having a motion vector, this
Motion vector corresponds to the timing of the image data.
The movement vector that has been sorted
The writing of image data to memory is controlled according to the
Since the motion compensation of the image data is performed, it is possible to obtain a good still image with little image deviation even if the image has a motion. For example, the image data of the ODD field without motion compensation is stored in the ODD field memory, and the image data of the next EVEN field is stored in the EVD field.
Move to the EN field memory based on the motion vector
Stored in the compensated state, the moving part is
The correction is made to almost the same position as the image data of the DD field. Therefore, the ODD field memory and the EVE
By sequentially reading out the image data stored in the N field memory, it is possible to obtain a good still image with little image deviation.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A still image processing apparatus according to the present invention will be described below with reference to FIG.

In FIG. 1, reference numeral 1 denotes a decoder for an MPEG2 signal which is an image encoding method. This MPEG2
The decoder 1 is supplied with the serial data encoded by MPEG2, performs decoding processing, and restores the image data. Further, a motion vector is decoded from the serial data and supplied to the time axis adjusting circuit 2.

Since the motion vector is generated for the image data in units of macroblocks (16 pixels × 16 lines) as shown in FIG. 2, the timing of the image data restored and output from the MPEG2 decoder 1 The timing at which the motion vector for the image data is output does not match. Therefore, the rearrangement of the motion vectors is performed by the time axis adjusting circuit 2 so that the motion vectors correspond to the timing of the image data. Further, since this motion vector represents the motion from one frame or one field before (or after), the image data indicating the position one field before can be calculated by calculation. For this reason, motion compensation is enabled by the motion vector.

The image data of the ODD field of the image data restored by the MPEG2 decoder 1 is stored in the ODD field memory 3 by a write command from the controller 5.
Is stored. Further, the image data in the EVEN field is used for the EVEN by a write command from the controller 5.
It is stored in the field memory 4. Here, for example, EV
The image data in the EN field is stored in the EVEN field
When storing in the memory 4, the controller 5 controls the time axis.
Based on the rearranged motion vectors from the
To generate a write instruction, and write a field memo for EVEN.
Motion compensation by controlling the writing of image data to
Do.

ODD field memory 3 and EVE
The image data stored in the N field memory 4 is sequentially supplied to the output circuit 6 according to a read command from the controller 5.

The output circuit 6 is composed of a D / A converter and the like. The supplied image data is converted into an analog signal, and then a synchronizing signal is added to form an image signal which is an interlace signal. This image signal is supplied to a monitor television or the like (not shown) to perform image display.

Next, the operation of the still image processing apparatus is shown in FIG. FIG. 3A is a diagram illustrating movement of an object on a screen, and a background image is displayed together with the object on the screen. The object at the position (a) is shown by a hatched line moved four dots to the right in the figure and moved two lines downward after one frame has elapsed (b).
It is said. At this time, the motion vector in the case of frame forward prediction (motion compensation from the frame preceding by one frame) is set to -4 in the horizontal direction and -2 in the vertical direction. When the motion for one field is calculated from this motion vector, 1
The movement for the field is half the movement for one frame in the horizontal direction = −2 and the vertical direction = −1.

The ODD field memory 3 stores, for example, image data when the object is at the position (a).
FIG. 3B shows a display screen formed from the image data stored in the ODD field memory 3.

The image data of the EVEN field next to the ODD field in which the image data is stored is subjected to motion compensation by the controller 5 based on the value indicating the motion of one field described above , and the EVEN field memo is written.
In the memory 4, the image data subjected to the motion compensation is stored.
You. 3C and 3D show display screens formed from the image data before the motion compensation is performed and the image data after the motion compensation is performed.

A portion corresponding to the position of the object before the motion compensation is performed as shown by hatching in FIG. 3D needs to display a background image. For this reason, for example, new image data is generated by interpolating the image data in the ODD field memory 3, and this image data is stored in the EVEN field memory 4 corresponding to the position of the object before the motion compensation is performed. As a result, the background image is displayed on the screen.

The image data stored in the ODD field memory 3 is subjected to motion compensation and the image data stored in the EVEN field memory 4 is transferred to the controller 5.
Are sequentially read by a read command from The read image data is supplied to the output circuit 6, where it is converted into an image signal which is an interlace signal, and a still image with little image fluctuation is displayed as shown in FIG. 3E.

As described above, according to the present embodiment, since the image stored in the EVEN field memory 4 is subjected to motion compensation based on the motion vector, the image data stored in the ODD field memory 3 and the EVEN By sequentially reading the image data stored in the field memory 4, a still image with less image deviation can be easily obtained.

Incidentally, in the above-described embodiment, EVEN
The motion-compensated image data is stored in the EVEN field memory 4. However, the image data of the EVEN field is stored in the EVEN field memory 4 as it is.
OD by performing motion compensation only on the image data in the ODD field
It may be stored in the D field memory 3.
In this case, it is assumed that motion compensation for advancing only the image data of the ODD field by one field is performed and then stored in the ODD field memory 3.

Further, the image data of both the ODD field and the EVEN field are motion-compensated to perform the ODD field memory 3 and the EVEN field memory 4.
May be stored. In this case, after performing motion compensation for advancing the image data of the ODD field by フ ィ ー ル ド field, the image data is stored in the ODD field memory 3 and EVE
After performing motion compensation for returning the N-field image data by フ ィ ー ル ド field, the image data is stored in the EVEN field memory 4.

Further, the image data stored in the ODD field memory 3 and the EVEN field memory 4 is not limited to the motion-compensated data.
The motion compensation is performed on the image data stored in the field memory 4 for VEN, the image data stored in the field memory 3 for ODD, the image data stored in the field memory 4 for EVEN, or the image data stored in both field memories. It is a matter of course that a still image with less image deviation can be obtained by forming an image using the image data subjected to the above.

In this example, the case where the MPEG2 signal is used has been described. However, if the signal is a signal having a motion vector or a signal capable of generating a motion vector, the MPE signal is used.
It is not limited to the G2 signal.

[0024]

According to the first aspect of the present invention, a motion vector is separated from an image data signal having a motion vector, and the motion vector corresponds to the timing of the image data.
And the sorted motion
Writing of image data to memory is controlled according to the vector
Is performed, motion compensation of the image data is performed.
Even with a moving image, a good still image with little image deviation can be obtained. For example, OD without motion compensation
Store image data of D field in ODD field memory and EVEN field memory
Motion compensation for the image data of the next EVEN field
By moving the image data to the
D field image data and EVEN field image
The image data is at substantially the same position. For this reason, by sequentially reading out the image data stored in the ODD field memory and the EVEN field memory, it is possible to obtain a good still image with little image deviation.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment of a still image processing apparatus according to the present invention.

FIG. 2 is a diagram showing a configuration of a micro block.

FIG. 3 is a diagram showing the operation of the embodiment.

FIG. 4 is a diagram illustrating an operation of a conventional still image processing device.

[Explanation of symbols]

 1 MPEG2 decoder 2 Time axis adjustment circuit 3 Field memory for ODD 4 Field memory for EVEN 5 Controller 6 Output circuit

Claims (1)

(57) [Claims] 1. A decoding means for separating the motion vector from the image data signals having a motion vector, a motion vector output from said decoding means image data
Time axis to sort according to data timing
Adjusting means, data memory means for storing image data of continuous odd and even fields, and memory control means for controlling storage and reading of data in the data memory means, wherein the memory control means Above data memory means
Picture of odd and / or even fields
When storing image data, the time axis adjustment means
Motion compensation based on the sorted motion vectors.
Performed with the still-image processing apparatus characterized by forming an image data of sequentially reads one-frame image data stored in said data memory means.