JP2837771B2 - Encoding and decoding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for encoding and decoding video signals and high-definition video signals.

[0002]

2. Description of the Related Art In general, since a video signal has a very large amount of information, a method of reducing the amount of information is used in recording or transmission so that image quality deterioration is not visually noticeable by high efficiency coding. .

[0003] As a conventional encoding device, for example, there is an encoding device using orthogonal transform. FIG. 7 is a block diagram showing the configuration of this conventional encoding device. Hereinafter, the operation will be described with reference to FIG.

[0004] First, a signal input from an input terminal 1 is divided into blocks of a predetermined size by a blocking circuit 2. Next, after orthogonal transform is performed on each block by the orthogonal transformer 3, the blocks are encoded by the encoder 4. Here, since the data amount after encoding is predetermined,
The encoder 5 performs control so that the data amount after encoding becomes equal to or less than a predetermined amount. For example, the data amount of the m blocks is x, the data amount after the m blocks are encoded is y, the predetermined data amount is z, and x
Control is performed so that> z ≧ y.

[0005]

However, the conventional configuration described above has the following problems.

That is, when a single type of signal, that is, a standard video signal or a wideband high-definition video signal is input, each of the input signals has its own encoded data format. Therefore, it is necessary to separately prepare encoding and decoding devices corresponding to different types of video signals.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional encoding / decoding apparatus, and encodes and decodes an input signal which can correspond to either a standard video signal or a high-definition video signal. It is an object to provide a chemical conversion device.

[0008]

In order to achieve this object, an encoding and decoding apparatus according to the present invention uses an image A or an image B whose number of vertical pixels is twice as large as that of the image A as an input. , The image B is divided into two on the time axis to obtain an image C and an image D, and the image A or the image C is highly efficiently encoded, and the encoded signal is
And first encoding means for obtaining an image D ,
Second encoding means for obtaining an encoded signal, first decoding means for decoding a signal encoded by the first encoding means, and decoding of a signal encoded by the second encoding means A second decryption unit for performing the operation, and an output of the first decryption unit and a second
And a combiner for combining the output of the decoding means.

[0009]

According to the present invention, the first encoding means performs a common encoding process on the image A and the image B according to the above configuration, so that the encoded data of any input image is Decoding can also be performed by the decoding device. In other words, even if the image B is encoded, the dedicated decoding device for the image A can decode even if only the encoded data encoded by the first encoding unit is used.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a configuration of an encoding apparatus according to a first embodiment of the present invention. In the figure, an input terminal 10 is a terminal for inputting an image A having a screen aspect ratio of 9:16, and an input terminal 11 is an image having a screen aspect ratio of 9:16 and having twice the number of vertical pixels as the image A. A terminal for inputting B, a divider 12 divides the image B into fields on the time axis to obtain an image C and an image D.
A switch that outputs an image A in the mode of encoding the image B, and outputs an image C in the mode of encoding the image B. The first encoding unit 14 encodes the output of the switch 13 with high efficiency to produce an encoded signal X. Output means, second encoding means 15
Means for efficiently encoding the image D to output a coded signal Y, output terminal 16 is a terminal for outputting the coded signal X, and output terminal 17 is a terminal for outputting the coded signal Y. .

FIG. 2 is a block diagram showing the configuration of the decoding device according to the first embodiment of the present invention. In the figure,
The input terminal 30 is a terminal for inputting the encoded signal X,
The input terminal 31 is a terminal for inputting the encoded signal Y,
The first decoding unit 32 is a reverse process of the first encoding unit 14 and decodes the encoded signal X to obtain an image A ′ which is a reproduced image of the images A and C. Decoding means 3
3 is a reverse process of the second encoding unit 18 for decoding the encoded signal Y to obtain a reproduced image of the image D;
The switch 34 is a switch for selecting the case where the coded signal X has coded the image A and the case where the coded signal X has been coded. The synthesizer 35 is a reverse process of the time division in the coding device.
An output terminal 36 is a terminal for outputting the image A ', and an output terminal 37 is a terminal for outputting the image B'.

FIGS. 3 and 4 are diagrams showing the relationship between the vertical pixels of the images A and B for explaining the operation of the present embodiment.

As shown in FIG. 3, an image A is a signal having an interleave relationship between fields. Since this signal is handled by the first encoding unit 14 on a frame basis,
Use a non-interleaved signal. This is the framed signal shown in FIG. Then, the first decoding means 34 converts the signal into an interleaved signal. This is the image A 'shown in FIG.

On the other hand, as shown in FIG.
Has twice as many vertical pixels. That is, the image A is a standard TV
Image B means a wide version of the signal. Image B is a broadband high-definition TV.
Means a signal. This image B is time-divided by the divider 12 on a field-by-field basis, so that an image C
Can have the same form as the framed signal shown in FIG. Therefore, the first encoding unit 14 can perform exactly the same processing on the image A and the image C.

In the decoding apparatus, the picture C is combined with the picture D to obtain the picture B ', but the picture C can be outputted as the picture A'. In this case, the image A 'in FIG.
The first field of image B is the image A
Is output as a signal for two fields.

The encoding apparatus of FIG. 1 described above and FIG.
In the decoding apparatus, the first encoding means 14 and the first decoding means 32 are common components for both modes of the images A and B, and are identical circuits in both modes. Other components are circuits necessary only for the mode of the image B.
Therefore, a signal encoded in the mode of the image B can be decoded by a decoding device dedicated to the mode of the image A. That is,
If the image B is encoded by the encoding apparatus of the present embodiment, it is possible to obtain the image B 'by the decoding apparatus shown in FIG. 2, but it is only for the mode of the image A having only the first decoding means 32. Can also obtain an image A 'using only the encoded signal X.

As described above, according to this embodiment,
The first encoding unit 14 and the first decoding unit 32 are common components for the image A and the image B, and do not need to configure completely different circuits in both modes, and Even with the coded signal, the coded signal can be decoded by any decoding device.

Next, an encoding and decoding apparatus according to a second embodiment of the present invention will be described. The configuration block diagram of the present embodiment is the same as the configuration of the above-described first embodiment, and will not be described. The difference is in the method of dividing the image B. FIG. 5 shows the relationship between the vertical pixels of the image B for explaining the operation of the present embodiment.

As shown in FIG. 5, the image B is time-divided line by line by the divider 12 so that an image C obtained by division is the same as the framed signal shown in FIG. Form. Therefore, the first encoding unit 14 can perform exactly the same processing on the image A and the image C.

Further, in the decoding device, it is possible to output the image C as the image A 'as in the first embodiment. In this case, a signal obtained by thinning out the lines of the image B is output as a signal of the image A as shown as an image A ′ in FIG.

As described above, according to this embodiment,
The first encoding unit 14 and the first decoding unit 32 are common components for the image A and the image B, and the encoded signal of any input image is Can also be decrypted.

According to the first and second embodiments described above, when the image B is divided into fields or lines, the encoded signal X and the encoded signal Y each have a signal in the same frame. Therefore, when an error occurs in the transmission path, error correction in the frame can be performed using the coded signal X or the coded signal Y. Similarly, VTR
This is also useful when data is lost due to special playback such as variable speed playback.

Next, an encoding and decoding apparatus according to a third embodiment of the present invention will be described. The configuration block diagram of the present embodiment is the same as that of the above-described first embodiment, and a description thereof will be omitted. The difference is the method of dividing the image B.

In this embodiment, the image B is time-divided by the divider 12 for each frame. When the first field of the image B is considered, it is the same as that of the first embodiment, and has the relationship of the vertical pixels shown in FIG. The difference from the first embodiment is that in the case of the field division of the first embodiment, the image C is composed of the first field, the third field, the fifth field, and the odd (or even) field. In the example, since the frame is divided, the first field and the second field make up one frame, and the fifth field and the sixth field
One frame is constituted by the field, one frame is constituted by the ninth field and the tenth field,..., And thus consists of odd (or even) frames.

As described above, according to the present embodiment,
The first encoding unit 14 and the first decoding unit 32 are common components for the image A and the image B, and the encoded signal of any input image is Can also be decrypted.

According to each of the above-described embodiments, the first encoding unit 14 and the second encoding unit 15 and the first decoding unit 32 and the second decoding unit 33 are the same. Therefore, it is not necessary to newly provide an encoding unit and a decoding unit for a high-definition TV signal.

Next, a decoding apparatus according to a fourth embodiment of the present invention will be described. FIG. 6 is a block diagram showing the configuration of the decoding apparatus according to this embodiment.

In FIG. 6, an input terminal 40 is a terminal for inputting a coded signal X, and a decoding means 41 decodes the coded signal X to reproduce an image A 'which is a reproduced image of the images A and C.
Filter 42 is a filter for band limiting the image A ', and switch 43 selects the output of the decoding means 41 when decoding a signal obtained by encoding the image A, and encodes the image B. When decoding the decoded signal, a switch for selecting the output of the filter 42, and an output terminal 44 is a terminal for outputting the decoded image A '.

In this embodiment, an image quality improving means for outputting an encoded signal X obtained by encoding an image B as an image A 'is provided, and a decoding means 41 is provided in the first embodiment in the first embodiment. It is the same as the decoding means 32.

When an image C is output as an image A 'as shown in FIG. 4 or 5, a signal is obtained by simply thinning the vertical pixels of the original image B by half. Therefore, unnaturalness is conspicuous visually due to turning back by thinning. Therefore, by limiting the band by the filter 42,
Visual improvement can be achieved. The output of the filter 42 may have an interleaving relationship as the image A ', and the number of taps, coefficients, delay time, and the like of the filter itself are not limited.

As described above, according to this embodiment,
Even if a signal obtained by encoding the image B is decoded by a decoding device dedicated to the image A having only the decoding unit 41, a visually improved image A 'can be obtained.

In each embodiment, an input image is converted to a standard TV signal having an aspect ratio of 9:16 and a wide-band high-definition TV.
The signal was used, but this is not a limitation.

Further, the filter 42 in the fourth embodiment
Can also be used in the decoding apparatus in the above-described first, second and third embodiments.

Further, the divider 12 in each embodiment can be easily constructed by using a semiconductor memory and using a read clock having a period of に 対 し of a write clock to the memory.

The first encoding means may have the same structure as the second encoding means.

[0037]

As described above, according to the present invention, it is possible to perform encoding in accordance with any of the screens of the standard TV signal and the high-definition TV signal. Since decoding means is common to each signal, not only circuit compatibility, but also coded signals corresponding to high-definition TV signals can be decoded by other image-specific decoding devices, so that data compatibility is improved. There is also.

When the present invention is applied to a VTR (Video Tape Recorder), tape compatibility in which a high-definition TV signal recorded on a VTR dedicated to a standard TV signal can be reproduced as a standard TV signal can be realized. The effect is very large.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an encoding device according to an embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a decoding device according to an embodiment of the present invention.

FIG. 3 is a diagram illustrating a relationship between vertical pixels of an input image A according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating a relationship between vertical pixels of an input image B according to the first embodiment of the present invention.

FIG. 5 is a relationship diagram of a vertical image of an input image B according to the second embodiment of the present invention.

FIG. 6 is a block diagram illustrating a configuration of a decoding device according to a fourth embodiment of the present invention.

FIG. 7 is a block diagram illustrating a configuration of a conventional encoding device.

[Explanation of symbols]

 12 Divider (Means) 14 First Encoding Means 15 Second Encoding Means 32 First Decoding Means 33 Second Decoding Means 35 Synthesizer (Means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-58-196787 (JP, A) JP-A-62-206977 (JP, A) JP-A-59-178886 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) H04N ^7/ 24-7/68 H04N ^7/ 00-7/088

Claims (11)

(57) [Claims] 1. A first input means for inputting an image A, a second input means for inputting an image B having twice the number of vertical pixels of the image A, and an input signal input by the second input means. Dividing means for dividing the image B into two on the time axis to obtain an image C and an image D, and a first means for efficiently encoding the image A or the image C to obtain a first encoded signal. Encoding means for encoding the image D with high efficiency, and forming a second encoded signal
Obtaining a second and a coding means, said first encoding means, the same reference numerals regardless of the input image
An encoding device for performing an encoding process. 2. An encoding apparatus according to claim 1, wherein said second encoding means is the same as said first encoding means. 3. The encoding apparatus according to claim 1, wherein the dividing means divides the image B into odd-numbered fields and even-numbered fields. 4. The encoding apparatus according to claim 1, wherein the dividing means divides the image B into odd-numbered lines and even-numbered lines. 5. The encoding apparatus according to claim 1, wherein the dividing unit divides the image B into odd-numbered frames and even-numbered frames. 6. A first decoding means for decoding the signal X encoded by the first encoding means of claim 1, and a signal Y encoded by the second encoding means of claim 1. A decoding device comprising: a second decoding unit that decodes a first decoding unit; and a combining unit that combines an output of the first decoding unit and an output of the second decoding unit. 7. The decoding device according to claim 6, wherein the second decoding means is the same as the first decoding means. 8. The decoding apparatus according to claim 6, wherein the synthesizing means is configured to synthesize the division processing on the time axis in the encoding means with the original time axis. 9. A decoding device comprising: decoding means for decoding a signal X encoded by the first encoding means according to claim 1; and a filter for band-limiting an output of the decoding means. 10. An encoded signal X inputted to a decoding means.
10. The decoding apparatus according to claim 9, wherein when is a signal obtained by encoding the image A, the output of the decoding means is used as the output of the decoding apparatus. 11. An encoded signal X input to a decoding means.
10. The decoding apparatus according to claim 9, wherein in the case of a signal obtained by encoding the image B, an output of a band-limited filter is used as an output of the decoding apparatus.