JP2001238210A - Hierarchical coder, hierarchical decoder, video signal transmission system, medium, and information aggregates - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem such that a conventional hierarchical decoder has to add an edge detector and an edge emphasizing unit as the hardware for the edge emphasis to enhance quality of a subjective image. SOLUTION: The hierarchical decoder is provided with two high efficiency decoders 101, 102 that receive two compressed bit streams and decode them for each layer and with a resolution converter 103 that has a filter to regulate the resolution between layers of video image signals decoded for each layer and that the filter characteristic of the filter is selected to emphasize a prescribed frequency band of the video image signals decoded by each layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a hierarchical coding apparatus, a hierarchical decoding apparatus, a video signal transmission system, a medium,
And information aggregates.

[0002]

2. Description of the Related Art The configuration and operation of a conventional hierarchical coding device, a conventional hierarchical decoding device, and a conventional video signal transmission system including these devices will be described below with reference to FIG. It is assumed that the input video signal has two hierarchies.

[0003] First, the configuration and operation of a conventional hierarchical coding apparatus will be described. In FIG. 8, 801 is a first resolution converter, 802 is a first high-efficiency encoder,
803 is a second resolution converter, 804 is a difference signal generator, and 805 is a second high efficiency encoder.

The first resolution converter 801 converts the input video signal into a low-resolution video signal and outputs the low-resolution video signal to a first high-efficiency encoder 802.

[0005] The first high-efficiency encoder 802 performs a predetermined high-efficiency encoding (here, MPEG2 compression) on the low-resolution video signal output from the first resolution converter 801, and generates a compressed bit stream. (Compressed bit stream of the low-resolution video signal) is output to a first high-efficiency decoder 806 of a conventional hierarchical decoding device to be described later, and the video signal obtained by locally decoding the compressed bit stream is output to a second Is output to the resolution converter 803.

[0006] The second resolution converter 803 up-converts the video signal, which has been locally decoded out from the first high-efficiency encoder 802, to the same resolution as the input video signal using an up-conversion filter. The up-converted video signal is output to the difference signal generator 804.

The difference signal generator 804 outputs a difference signal between the input video signal and the up-converted video signal output from the second resolution converter 803, and the second high efficiency encoder 805 outputs A compressed bit stream (enhancement layer compressed bit stream) obtained by encoding the difference signal with a predetermined high efficiency (here, MPEG2 compression) is converted into a second high efficiency decoder of a conventional hierarchical decoding device described later. 807.

The difference signal generator 804 and the second high-efficiency encoder 805 are integrated into one, and the input video signal and the up-converted video signal output from the second resolution converter 803 are input. It is also possible to configure a highly efficient encoder described above.

Next, the configuration and operation of the conventional hierarchical decoding device will be described. 8, 806 is a first high-efficiency decoder, 807 is a second high-efficiency decoder,
808 is a second resolution converter, 809 is an adder, 810
Is an edge detector and 811 is an edge enhancer.

[0010] The first high-efficiency decoder 806 converts the compressed bit stream of the low-resolution video signal output from the first high-efficiency encoder 802 of the hierarchical encoder into a compressed bit stream of the hierarchical encoder. The first high-efficiency encoder 802 performs predetermined high-efficiency decoding, which is the inverse conversion of the high-efficiency encoding performed by the first high-efficiency encoder, and converts the low-resolution video signal that is the decoded video signal into a second resolution converter. 808. Note that this low-resolution video signal, which is a decoded video signal, is converted to a low-resolution video by C
It is also possible to display at RT (not shown).

A second resolution converter 808 converts the decoded video signal of the low-resolution video signal output from the first high-efficiency decoder 806 into an up-convert filter (second resolution of the hierarchical coding apparatus). Using the same up-conversion filter of converter 803), up-conversion is performed to the same resolution as the above-mentioned input video signal, and the up-converted decoded video signal is output to adder 809.

[0012] The second high-efficiency decoder 807 converts the compressed bit stream of the enhancement layer output from the second high-efficiency encoder 805 of the hierarchical encoder into the second bit of the hierarchical encoder. And performs a predetermined high-efficiency decoding which is an inverse transform of the high-efficiency encoding performed by the high-efficiency encoder 805, and outputs a decoded signal to the adder 809.

The adder 809 is used for the second high-efficiency decoder 8
07 and the second resolution converter 80
8 to output a decoded video signal obtained by adding the up-converted video signal.

The edge detector 810 is used to increase the subjective image quality of the decoded video signal output from the adder 809.
The edge is detected, and the edge enhancer 811 increases the signal level of the edge detected by the edge detector 810,
Increase the subjective image quality of the decoded video signal.

When the difference signal generator 804 and the second high-efficiency encoder 805 are combined into one in the hierarchical encoder, the second high-efficiency decoder 807 and the adder 809 are connected. Collectively, Enhancement La
yer compressed bit stream and second resolution converter 8
It is also possible to configure a high-efficiency decoder using the video signal output from the input unit 08 as an input.

[0016]

However, in the conventional video signal transmission system, there is a problem that the edge enhancement for improving the subjective image quality cannot be performed without adding an edge detector and an edge enhancer. .

The present invention has been made in consideration of such a problem, and is capable of improving the subjective image quality without adding hardware. The hierarchical coding apparatus, the hierarchical decoding apparatus, the video signal transmission system, and the medium , And an information aggregate.

[0018]

Means for Solving the Problems The first invention (claim 1)
Corresponds to N input video signals in terms of resolution (N
Is an integer of 2 or more), and N codes that respectively generate and output N compressed bit streams by encoding the layered video signals, respectively. And a second resolution conversion unit having a filter for converting the resolution of the hierarchized video signal by indirectly or directly using the hierarchized video signal, and outputting a video signal. The characteristic is set so as to cancel noise included in the resolution-converted video signal, and the encoding is performed to encode at least the highest-level video signal among the N hierarchical video signals. The means uses the video signal output from the second resolution conversion means based on a predetermined criterion when the compressed bit stream is generated. That is a hierarchical encoding apparatus.

According to a second aspect of the present invention (corresponding to claim 2), the encoding means decodes the generated compressed bit stream by encoding the hierarchized video signal, The video signal obtained by this decoding is output to the second resolution conversion means, and the resolution conversion is performed indirectly using the hierarchized video signal. A hierarchical encoding apparatus according to the first aspect of the present invention, which performs resolution conversion of a video signal obtained by the method.

According to a third aspect of the present invention (corresponding to claim 3), the resolution of the hierarchized video signal is directly converted,
The hierarchical encoding device according to the first aspect of the present invention is characterized in that resolution conversion is performed on the hierarchized video signal itself by the first resolution converting means.

According to a fourth aspect of the present invention (corresponding to claim 4), the number of input video signals is N (N is an integer of 2 or more) with respect to resolution.
A hierarchical decoding device that inputs and decodes an output from a hierarchical encoding device that outputs N compressed bit streams by layering and encoding the N compressed bit streams. (N-1) decoding means having N decoding means for decoding for each layer and filters for adjusting the resolution between the layers of the video signal decoded for each layer. A third resolution conversion unit, wherein the filter characteristics of the filter are set so as to emphasize a predetermined frequency band of the video signal decoded for each layer. Device.

According to a fifth aspect of the present invention (corresponding to claim 5), the number of input video signals is N (N is an integer of 2 or more) with respect to resolution.
A hierarchical coding apparatus that outputs N compressed bit streams by layering and encoding, and N decoding means that inputs the N compressed bit streams and decodes each layer. And (N-1) third resolution conversion means having filters for adjusting the resolution between the layers of the video signal decoded for each layer, and the filter characteristics of the filters are And a hierarchical decoding device set to emphasize a predetermined frequency band of the video signal decoded for each layer.

According to a sixth aspect of the present invention (corresponding to claim 6), according to the present invention, the number of input video signals is N (N is an integer of 2 or more) with respect to resolution.
First resolution conversion means for hierarchizing the video signal, N encoding means for respectively generating and outputting N compressed bit streams by encoding the hierarchized video signals, and A second resolution conversion means having a filter for outputting a video signal by directly or indirectly converting the resolution of the converted video signal, wherein the filter characteristic of the filter is the resolution conversion. Encoding means for canceling noise included in the video signal to be encoded, and encoding the video signal of at least the highest layer among the N layered video signals, A layer-type encoding apparatus that uses the video signal output from the second resolution conversion unit based on a predetermined criterion when the stream is generated; Enter the compressed bit stream,
(N-1) third decoding means having N decoding means for decoding for each layer and filters for adjusting the resolution between the layers of the video signal decoded for each layer. A hierarchical decoding device comprising:
A video signal transmission system comprising:

According to a seventh aspect of the present invention (corresponding to claim 7), the number of input video signals is N (N is an integer of 2 or more) with respect to resolution.
First resolution conversion means for hierarchizing the video signal, N encoding means for respectively generating and outputting N compressed bit streams by encoding the hierarchized video signals, and A second resolution conversion means having a filter for outputting a video signal by directly or indirectly converting the resolution of the converted video signal, wherein the filter characteristic of the filter is the resolution conversion. Encoding means for canceling noise included in the video signal to be encoded, and encoding the video signal of at least the highest layer among the N layered video signals, A layer-type encoding apparatus that uses the video signal output from the second resolution conversion unit based on a predetermined criterion when the stream is generated; Enter the compressed bit stream,
(N-1) third decoding means having N decoding means for decoding for each layer and filters for adjusting the resolution between the layers of the video signal decoded for each layer. And a hierarchical decoding device, wherein the filter characteristics of the filter are set so as to emphasize a predetermined frequency band of the video signal decoded for each layer. A video signal transmission system characterized in that:

An eighth aspect of the present invention (corresponding to claim 8) is a program for causing a computer to execute all or some of the functions of all or some of the first to seventh aspects of the present invention. And / or a medium carrying data, wherein the medium can be processed by a computer.

A ninth aspect of the present invention (corresponding to claim 9) is a program for causing a computer to execute all or some of the functions of all or some of the first to seventh aspects of the present invention. And / or data.

[0027]

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

(Embodiment 1) In the following, FIG.
The configuration and operation of the hierarchical decoding device according to the first embodiment will be described with reference to FIG.

The hierarchical decoding apparatus according to the first embodiment uses a Spatial Scalable Pr defined by MPEG2 (ISO / IEC13818-2).
It decodes a two-layer compressed bit stream that has been subjected to hierarchical coding by the file.

In FIG. 1, 101 is a first high-efficiency decoder, 102 is a second high-efficiency decoder, 103 is a resolution converter, and 104 is an adder.

As shown in FIG. 6C, the resolution converter 103 has an FIR (Finite Impulse R) whose filter coefficient is adjusted so as to have a filter characteristic having a frequency band in which power is raised.
response) filter. FIG. 6 (c)
Is a diagram showing the filter characteristics of the FIR filter included in the resolution converter 103. The horizontal axis represents frequency, and the vertical axis represents signal passing power.

The second high-efficiency decoder 102 is configured to output the Enhan signal output from the conventional hierarchical encoder (see FIG. 8).
A predetermined high-efficiency decoding, which is an inverse transform of the high-efficiency coding performed by the hierarchical coding device, is performed on the compressed bit stream of the segment Layer, and a decoded signal is output to the adder 104.

The first high-efficiency decoder 101 performs the processing on the compressed bit stream of the low-resolution video signal output from the conventional hierarchical coding apparatus (see FIG. 8) by the hierarchical coding apparatus. A predetermined high-efficiency decoding which is an inverse conversion of the high-efficiency coding is performed, and a low-resolution video signal which is a decoded video signal is output to the resolution converter 103. Note that the low-resolution video signal, which is the decoded video signal, can be displayed on a CRT (not shown) as a low-resolution video.

The resolution converter 103 converts the decoded video signal of the low resolution video signal output from the first high-efficiency decoder 101 into an FIR filter (shown in FIG. 1) independently in the horizontal and vertical directions. Up-converted to the same resolution as the decoded signal output from the second high-efficiency decoder 102 using the up-converting filter and the emphasis filter. The decoded video signal is output to the adder 104.

The output of the resolution converter 103 has many frequency bands in which a sense of resolution can be subjectively obtained.
This is because the edge that improves the subjective image quality is shown in FIG.
Since the signal exists in the frequency band where the power is raised as shown in FIG. 6C, the edge enhancement can be obtained by using the filter having the characteristic as shown in FIG. It is. Note that, as described later, the output of the decoded video signal output from the adder 104 also has many frequency bands.

The adder 104 is used for the second high-efficiency decoder 1
02, and outputs a decoded video signal obtained by adding the up-converted video signal output from the resolution converter 103 and the decoded signal output from the resolution converter 103.

It is to be noted that the hierarchical coding performed in the hierarchical coding apparatus as in the first embodiment is MPEG.
2 Spatial Scalable Profile
In the case of e, the second high-efficiency decoder 102 and the adder 104 are integrated into one, and the Enhancement L
aer compressed bit stream and resolution converter 103
A high-efficiency decoder that receives the output video signal and the video signal can also be configured.

(Embodiment 2) In the following, FIG.
The configuration and operation of the hierarchical encoding device, the hierarchical decoding device, and the video signal transmission system including the same in Embodiment 2 will be described with reference to FIG. Here, it is also assumed that the hierarchies are two hierarchies.

First, the configuration and operation of the hierarchical coding apparatus according to the second embodiment will be described. 2, reference numeral 201 denotes a first resolution converter, 202 denotes a first high-efficiency encoder, 203 denotes a second resolution converter, and 204 denotes a second resolution converter.
Is a difference signal generator, and 205 is a second high efficiency encoder.

The first high-efficiency encoder 202 generates a compressed bit stream (compressed bit stream of a low-resolution video signal), and converts it into a first high-efficiency decoder of a hierarchical decoding device described later. A means for outputting to the second resolution converter 203 a video signal obtained by decoding the compressed bit stream (hereinafter, referred to as local decode-out) and outputting the video signal to the second resolution converter 203.

FIR of second resolution converter 203
The filter coefficient of the filter is adjusted so as to have the filter characteristic shown in FIG. 6B, and only the low-resolution video signal can be conveniently filtered. FIG. 6B shows the FIR of the second resolution converter 203.
FIG. 4 is a diagram illustrating filter characteristics of a filter, wherein the horizontal axis represents frequency and the vertical axis represents signal passing power. FIG. 6A shows the pass bands of the low-resolution video signal and the enhancement layer, but an actual filter cannot perform ideal band division that completely separates these.

The first resolution converter 201 converts the resolution of the input video signal into a low-resolution video signal, and outputs the low-resolution video signal to the first high-efficiency encoder 202.

The first high-efficiency encoder 202 performs a predetermined high-efficiency encoding (here, MPEG2 compression) on the low-resolution video signal input from the first resolution converter 201, and generates a compressed bit stream. (Compressed bit stream of the low-resolution video signal) is output to the first high-efficiency decoder 101 of the hierarchical decoding device described later, and the video signal obtained by locally decoding out the compressed bit stream is converted to the second resolution. Output to converter 203.

The second resolution converter 203 operates in the horizontal direction,
The video signal locally decoded from the first high-efficiency encoder 202 is up-converted to the same resolution as the input video signal using an FIR filter (up-conversion filter shown in FIG. 2) independently in the vertical direction. The signal is converted and output to the difference signal generator 204.

The difference signal generator 204 outputs the difference signal between the input video signal and the up-converted video signal output from the second resolution converter 203 to the second high-efficiency encoder 205.

The second high-efficiency encoder 205 encodes the difference signal into a predetermined high-efficiency code (here, MPEG2 compression).
Compressed bit stream (Enhancement
(Layer compressed bit stream) to a second high-efficiency decoder.

It should be noted that, as in the second embodiment, the hierarchical scalar encoding is MPEG2 Spatial Scalab.
le profile, the differential signal generator 2
04 and the second high-efficiency encoder 205 into one,
It is also possible to configure a high-efficiency encoder that receives an input video signal and an up-converted video signal output from the second resolution converter 203 as inputs.

Next, the configuration and operation of the hierarchical decoding device will be described. In FIG. 2, 101 is a first high-efficiency decoder, 102 is a second high-efficiency decoder, 206
Is a third resolution converter, and 104 is an adder.

FIR of third resolution converter 206
The filter coefficient of the filter is adjusted so as to have a filter characteristic having a frequency band in which the power is raised as shown in FIG. 6C. Therefore, the output of the third resolution converter 206 has many frequency bands in which a sense of resolution can be subjectively obtained.

The second high-efficiency decoder 102 applies a second high-efficiency encoder to the compressed bit stream of the enhancement layer output from the second high-efficiency encoder 205 of the hierarchical encoder. A predetermined high-efficiency decoding, which is an inverse transform of the high-efficiency coding performed in 205, is performed, and a decoded signal is output to the adder 104.

The first high-efficiency decoder 101 converts the low-resolution video signal compressed bit stream output from the first high-efficiency encoder 202 of the hierarchical encoder into a first bit stream.
Performs a predetermined high-efficiency decoding, which is an inverse transform of the high-efficiency encoding performed by the high-efficiency encoder 202, and converts the low-resolution video signal that is the decoded video signal into a third
Output to

The third resolution converter 206 operates in the horizontal direction,
Using an FIR filter (a filter having a combination of an up-conversion filter and an emphasis filter as shown in FIG. 2) independently in the vertical direction,
The decoded video signal of the low-resolution video signal output from the first high-efficiency decoder 101 is output to the second high-efficiency decoder 1.
02 is up-converted to the same resolution as the decoded signal that is the output of the output signal 02 and output to the adder 104.

The adder 104 is the second high-efficiency decoder 1
02 and the output of the third resolution converter 20
6 to output a decoded video signal obtained by adding the up-converted video signal.

It should be noted that the hierarchical coding performed in the hierarchical coding apparatus as in the second embodiment is MPEG
2 Spatial Scalable Profile
In the case of e, the second high-efficiency decoder 102 and the adder 104 are integrated into one, and the Enhancement L
It is also possible to configure a high-efficiency decoder that receives the compressed bit stream of the ayer and the video signal output from the third resolution converter 206 as inputs.

As described above, the two compressed bit streams, which are the outputs of the hierarchical encoder, are transmitted using the predetermined transmission protocol, and after being received, the video signal is decoded by the hierarchical decoder. Can be transmitted.

(Embodiment 3) In the following, FIG.
The configuration and operation of the hierarchical encoding device, the hierarchical decoding device, and the video signal transmission system including the same in Embodiment 3 will be described with reference to FIG.

First, the configuration and operation of the hierarchical coding apparatus according to the third embodiment will be described.

In FIG. 3, reference numeral 301 denotes a second resolution converter. The second resolution converter 301 according to the third embodiment uses an FIR filter whose filter coefficient is adjusted so as to cancel noise. Have.

That is, the filter coefficients of the FIR filter included in the second resolution converter 301 are adjusted so as to have the filter characteristics shown in FIG. 7B. FIG. 7B shows the FIR in the horizontal and vertical directions.
It is a figure which shows the pass band of a filter, a horizontal axis shows a frequency and a vertical axis | shaft shows the passing power of a signal.

FIG. 7A shows a low resolution video signal and Enha.
It shows the passband of the element layer, but as already mentioned, it is not possible for an actual filter to do the ideal band splitting that completely separates them. However, as shown in FIG. 7B, the filter included in the second resolution converter 301 in the video signal encoding device is a filter in the low-resolution video signal in the first high-efficiency encoder 202. It has a characteristic of substantially cutting frequency components. Since the noise that degrades the image quality is generated by the high-frequency component of the low-resolution video signal that includes such a large amount of compression-coding distortion, the second resolution converter 301 has the above-described filter, and thus the noise cancellation. The effect is exhibited.

The first resolution converter 201 converts the input video signal into a low-resolution video signal and outputs it.

The first high-efficiency encoder 202 performs predetermined high-efficiency encoding (here, MPE) on the low-resolution video signal.
G2 compression), and outputs a compressed bit stream (a compressed bit stream of a low-resolution video signal) and a video signal obtained by locally decoding out the compressed bit stream.

The second resolution converter 301 operates in the horizontal direction,
Locally decoded out from the first high-efficiency encoder 202 using an FIR filter (a filter having a combination of an up-conversion filter and a noise cancellation filter as shown in FIG. 3) independently in the vertical direction. The video signal is up-converted to the same resolution as the input video signal.

The difference signal generator 204 outputs a difference signal between the input video signal and the up-converted video signal output from the second resolution converter 301, and the second high efficiency encoder 205 outputs the difference signal. A compressed bit stream (En) in which a signal is encoded at a predetermined high efficiency (here, MPEG2 compression)
output the compressed bit stream of the H.Hancement Layer.

It should be noted that, as in the third embodiment, the hierarchical scalar coding of MPEG2
le profile, the differential signal generator 2
04 and the second high-efficiency encoder 205 into one,
It is also possible to configure a high-efficiency encoder that receives an input video signal and an up-converted video signal output from the second resolution converter 301 as inputs.

Next, the configuration and operation of the hierarchical decoding apparatus according to the third embodiment will be described.

In FIG. 3, reference numeral 102 denotes a second high-efficiency decoder, and reference numeral 302 denotes a third resolution converter.

FIR of Third Resolution Converter 302
The filter coefficient of the filter is adjusted so as to have the filter characteristic shown in FIG. FIG. 7C shows the FIR of the third resolution converter 302.
FIG. 4 is a diagram illustrating filter characteristics of a filter, wherein the horizontal axis represents frequency and the vertical axis represents signal passing power. As shown in FIG. 7 (c), the FIR filter of the third resolution converter 302 has an enhancement layer.
Since the frequency components corresponding to the low-frequency components are not cut, a frequency band in which the power rises as described later can be obtained.

The second high-efficiency decoder 102 outputs the Enhanceme output from the second high-efficiency encoder 205.
For the compressed bit stream of the nt Layer, the second
The high-efficiency encoder 205 performs predetermined high-efficiency decoding, which is an inverse transform of the high-efficiency encoding performed by the high-efficiency encoder 205, and outputs a decoded signal to the adder 104.

The first high-efficiency decoder 101 applies the first high-efficiency encoder 2 to the compressed bit stream of the low-resolution video signal output from the first high-efficiency encoder 202.
A predetermined high-efficiency decoding, which is an inverse transform of the high-efficiency coding performed in step S 02, is performed, and a low-resolution video signal that is a decoded video signal is output to the third resolution converter 302.

The third resolution converter 302 operates in the horizontal direction,
The FIR filter (the up-conversion filter shown in FIG. 3) is used independently of each other in the vertical direction to convert the decoded video signal of the low-resolution video signal into a second high-efficiency decoder 1.
02 is up-converted to the same resolution as the decoded signal that is the output of the output signal 02 and output to the adder 104.

The adder 104 is the second high-efficiency decoder 1
02 and the third resolution converter 30
2 to output a decoded video signal obtained by adding the up-converted video signal.

Here, the decoded signal output from the second high-efficiency decoder 102 has the same frequency component as the difference signal for the enhancement layer output from the difference signal generator 204, that is, It has a frequency component obtained by removing the frequency component output from the second resolution converter 301 from the frequency component of the video signal. Therefore,
The output of the decoded video signal, which is the output of the adder 104, has characteristics as shown in FIG.

The frequency band in which the power is raised in FIG. 7D is a frequency band in which a sense of resolution can be subjectively obtained. As already described, since the edge for improving the subjective image quality exists in the frequency band where the power is raised as shown in FIG. 7D, the edge existing in the frequency band where the power is raised in this way is emphasized. Obtainable.

It should be noted that the hierarchical coding performed by the hierarchical coding apparatus as in the third embodiment is MPEG
2 Spatial Scalable Profile
In the case of e, the second high-efficiency decoder 102 and the adder 104 are integrated into one, and the Enhancement L
It is also possible to configure a high-efficiency decoder using the compressed bit stream of the ayer and the video signal output from the third resolution converter 302 as inputs.

As described above, the two compressed bit streams output from the hierarchical encoding device are transmitted using a predetermined transmission protocol, received, and then decoded by the hierarchical decoding device. Can be transmitted.

(Embodiment 4) In the following, mainly, FIG.
The configuration and operation of the hierarchical encoding device, the hierarchical decoding device, and the video signal transmission system including the same in Embodiment 4 will be described with reference to FIG.

First, the configuration and operation of the hierarchical coding apparatus according to Embodiment 4 will be described. In FIG. 4, reference numeral 401 denotes a second resolution converter.

The first resolution converter 201 converts the input video signal into a low-resolution video signal and outputs it.

The first high-efficiency encoder 202 applies a predetermined high-efficiency encoding (here, M
PEG2 compression) and outputs a compressed bit stream (a compressed bit stream of a low-resolution video signal).

The second resolution converter 401 operates in the horizontal direction,
The FIR filter having the filter characteristic shown in FIG. 6B (up-conversion filter shown in FIG. 4) is used independently of the FIR filter of the second resolution converter 203 independently in the vertical direction. The low-resolution video signal output from the first resolution converter 201 is up-converted to the same resolution as the input video signal.

As described above, the signal up-converted in the second resolution converter 401 is not a video signal locally decoded out from the first high-efficiency encoder 202, but a signal from the first resolution converter 201. Embodiment 4 is different from Embodiment 2 described above in that the output low-resolution video signal itself is used.

The difference signal generator 204 outputs a difference signal between the input video signal and the up-converted video signal output from the second resolution converter 401, and the second high-efficiency encoder 205 outputs the difference signal. A differential bit is output as a compressed bit stream (enhancement layer compressed bit stream) obtained by performing predetermined high-efficiency encoding (here, MPEG2 compression) on the differential signal.

Note that, as in the above-described fourth embodiment, the hierarchical coding is performed using the Spatial S of MPEG2.
In the case of the callable profile, the difference signal generator 204 and the second high-efficiency encoder 205 are combined into one, and the input video signal and the up-converted video signal output from the second resolution converter 401 are combined. Can be configured as a high-efficiency encoder that receives the input as the input.

The configuration and operation of the hierarchical decoding apparatus according to the fourth embodiment are the same as the configuration and operation of the hierarchical decoding apparatus according to the second embodiment, and a detailed description thereof will be omitted.

However, as described above, the signal up-converted in the second resolution converter 401 is
Instead of the video signal locally decoded out from the first high efficiency encoder 202, the first resolution converter 201
Since the low-resolution video signal is output from the second high-efficiency decoder 102, the Enhancem input from the second high-efficiency decoder 102
The compressed bit stream of the ent Layer is slightly different between the second embodiment and the fourth embodiment. However, the low-resolution video signal output from the first resolution converter 201 and the low-resolution video signal output from the first high-efficiency encoder 202 (local decode-out) are:
It has equivalent frequency components and does not differ significantly. Therefore, the decoded video signal output from the adder 104 provides a high-quality image with emphasized edges in any of the embodiments.

(Embodiment 5) In the following, mainly, FIG.
The configuration and operation of the hierarchical coding device, the hierarchical decoding device, and the video signal transmission system including the same in Embodiment 5 will be described with reference to FIG.

First, the configuration and operation of the hierarchical coding apparatus according to Embodiment 5 will be described. In FIG. 5, reference numeral 501 denotes a second resolution converter. As will be described later, the second resolution converter 501 in the fifth embodiment has a filter for canceling noise.

The first resolution converter 201 converts the input video signal into a low-resolution video signal and outputs it.

The first high-efficiency encoder 202 performs a predetermined high-efficiency encoding (here, M
PEG2 compression) and outputs a compressed bit stream (a compressed bit stream of a low-resolution video signal).

The second resolution converter 501 operates in the horizontal direction,
Independently in the vertical direction, an FIR filter having the same filter characteristics as the FIR filter of the second resolution converter 301 as shown in FIG. 7B (the up-converting filter and the noise canceling filter as shown in FIG. 5). Filter with the combined characteristics of the filters)
The low-resolution video signal output from the first resolution converter 201 is up-converted to the same resolution as the input video signal.

As described above, the signal up-converted in the second resolution converter 501 is not a video signal locally decoded out from the first high-efficiency encoder 202, but is a signal from the first resolution converter 201. Embodiment 5 is different from Embodiment 3 described above in that the output low-resolution video signal itself is used.

The difference signal generator 204 outputs a difference signal between the input video signal and the up-converted video signal output from the second resolution converter 401, and the second high-efficiency encoder 205 outputs the difference signal. A differential bit is output as a compressed bit stream (enhancement layer compressed bit stream) obtained by performing predetermined high-efficiency encoding (here, MPEG2 compression) on the differential signal.

Note that, as in the above-described fifth embodiment, the hierarchical coding of the MPEG-2 Spatial S
In the case of the callable profile, the difference signal generator 204 and the second high-efficiency encoder 205 are combined into one, and the input video signal and the video signal output from the second resolution converter 401 are input. A high efficiency encoder can also be configured.

The configuration and operation of the hierarchical decoding device according to the fifth embodiment are the same as the configuration and operation of the hierarchical decoding device according to the third embodiment, and a detailed description thereof will be omitted.

However, as described above, the signal up-converted by the second resolution converter 501 is
Instead of the video signal locally decoded out from the first high efficiency encoder 202, the first resolution converter 201
Since the low-resolution video signal is output from the second high-efficiency decoder 102, the Enhancem input from the second high-efficiency decoder 102
The compressed bit stream of the ent Layer is slightly different between the third embodiment and the fifth embodiment. However, the low-resolution video signal output from the first resolution converter 201 and the low-resolution video signal output from the first high-efficiency encoder 202 (local decode-out) are:
It has equivalent frequency components and does not differ significantly. Therefore, the decoded video signal output from the adder 104 provides a high-quality video with noise cancellation in any of the embodiments.

Note that the hierarchization in the present invention is performed in the above-described embodiment using MPEG2 (ISO / IEC138).
Spatial Scal specified in 18-2)
Although the encoding is performed by the “able Profile”, the encoding is not limited thereto, and may be performed by another hierarchical coding algorithm.

In the above-described embodiment, hierarchization is performed such that N = 2. However, the present invention is not limited to this. For example, N is an arbitrary integer of 2 or more. It may be performed.

The first resolution conversion means in the present invention corresponds to the first resolution converter in the above-described embodiment, but is not limited thereto. When the conversion is performed so as to be the above integer, for example, it may be composed of (N-1) resolution converters respectively corresponding to the (N-1) th layer from the lowest resolution layer.

Further, the second resolution converter in the present invention corresponds to the second resolution converter in the above-described embodiment, but is not limited thereto. When generating a compressed bit stream, any means may be used so long as the video signal output from the second resolution conversion means can be used based on a predetermined standard.

Further, in the above-described embodiment, the N encoding means according to the present invention is a combination of the first high-efficiency encoder, the second high-efficiency encoder and the difference signal generator. However, the present invention is not limited to this, and when the layering in the present invention is performed such that N is an integer of 2 or more, it may be composed of N encoding units.

In the above-described embodiment, the generation of the compressed bit stream by the encoding means according to the present invention is performed only in the second high-efficiency encoder, and the video signal output from the second resolution converter is output. However, the present invention is not limited to this. In short, the encoding means for encoding at least the highest hierarchical video signal out of the hierarchically arranged N video signals has the second configuration according to the present invention. The video signal output from the resolution conversion means may be used based on a predetermined reference.

Also, in the above-described embodiment, the N decoding means in the present invention are the same as the combination of the first high-efficiency decoder and the second high-efficiency decoder and adder. However, the present invention is not limited to this, and when the layering in the present invention is performed such that N is an integer of 2 or more, it may be constituted by N decoding means.

The third resolution converter according to the present invention corresponds to the third resolution converter in the above-described embodiment, but is not limited to this. In short, the third resolution converter according to the present invention comprises: When decoding the compressed bit stream, any means provided so as to be able to use the video signal output from the third resolution conversion means may be used.

In the above-described embodiment, the filters according to the present invention are independent FIR filters in the horizontal and vertical directions. However, the present invention is not limited to this. Is also good. However, since the FIR filters independent in the horizontal and vertical directions can independently select the frequency band to be enhanced and / or cut, more remarkable effects can be expected in edge enhancement and / or noise cancellation. . Further, when hierarchization is performed such that N is an arbitrary integer of 2 or more, a frequency band to be emphasized and / or cut in each hierarchy is selected by providing an independent filter in each hierarchy. can do.

Also, for example, the filter of the second resolution converter 203 of the hierarchical coding apparatus according to the second embodiment or the filter of the second resolution converter 401 of the hierarchical coding apparatus according to the second embodiment is standardized. And the third resolution converter 2 of the hierarchical decoding apparatus according to the second or fourth embodiment.
The frequency band emphasized in 06 may be freely selected.

For example, in the third or fifth embodiment,
, The third resolution converter 302 of the hierarchical decoding device in
And the frequency band to be cut by the second resolution converter 301 of the hierarchical encoding device in the third embodiment or the hierarchical resolution device 501 in the fifth embodiment is switched by a video signal. Is also good.

Further, the hierarchical coding apparatus and the hierarchical decoding apparatus of the present invention, in the above-described embodiment,
The hierarchical decoding device has a filter having a filter characteristic set to emphasize a predetermined frequency band of the video signal, or the hierarchical encoding device cancels noise included in the video signal. , But the present invention is not limited to this, and the hierarchical decoding device may be configured to enhance a predetermined frequency band of the video signal by a filter. The hierarchical encoding device may include a filter having a filter characteristic and having a filter characteristic set to cancel noise included in the video signal. For example, the hierarchical decoding device having the third resolution converter 206 according to the second or fourth embodiment, and the second resolution converter 301 according to the third embodiment
A video signal transmission system simultaneously provided with the hierarchical coding device having the above configuration can also be implemented.

Further, by creating a medium for carrying a program and / or data for causing a computer to execute all or a part of the functions of all or a part of the above-described embodiment, and utilizing the medium, The read program and / or data may execute the same operation as described above in cooperation with the computer.

Further, an information aggregate characterized by being a program and / or data for causing a computer to execute all or a part of the functions of all or a part of the above-described embodiment is prepared. By utilizing, the read program and / or data structure may cooperate with a computer to perform the same operation as described above.

Here, the data includes a data structure, a data format, a type of data, and the like. Further, the medium includes a recording medium such as a ROM, a transmission medium such as the Internet, and a transmission medium such as light, radio waves, and sound waves. The carried medium includes, for example, a recording medium on which a program and / or data is recorded, a transmission medium for transmitting the program and / or data, and the like. In addition, to be able to be processed by a computer means that, for example, in the case of a recording medium such as a ROM, it can be read by a computer, and in the case of a transmission medium, a program and / or data to be transmitted is Including that it can be handled by a computer as a result of the transmission. The information aggregate includes, for example, software such as a program and / or data.

Therefore, in the video signal layered coded transmission apparatus according to the first embodiment, the filter used for the resolution converter 103 is set with a filter coefficient such that the filter characteristic includes an edge emphasis (emphasis) effect. Thus, the functions of edge detection and edge enhancement can be realized without adding hardware.

Further, the video signal transmission system using the hierarchical coding device and the hierarchical decoding device according to the second embodiment
The filter used in the third resolution converter 206 has filter coefficients set so that the filter characteristics include an edge enhancement (emphasis) effect, thereby realizing the functions of edge detection and edge enhancement without adding hardware. can do.

Further, in the video signal transmission system using the hierarchical coding apparatus and the hierarchical decoding apparatus according to the third embodiment of the present invention, the filter used for the second resolution Since the filter coefficient is set so as to include the noise canceling effect, the functions of edge detection and edge enhancement can be realized without adding hardware.

Further, in the video signal transmission system using the hierarchical coding apparatus and the hierarchical decoding apparatus according to the fourth embodiment of the present invention, the filter used for the third resolution converter 206 has a filter characteristic. , Edge enhancement (emphasis)
By setting the filter coefficient so as to include the effect, the functions of edge detection and edge enhancement can be realized without adding hardware.

Also, in the video signal transmission system using the hierarchical coding device and the hierarchical decoding device according to the fifth embodiment of the present invention, the filter used for the second resolution Since the filter coefficient is set so as to include the noise canceling effect, the functions of edge detection and edge enhancement can be realized without adding hardware.

As described above, the hierarchical decoding apparatus of the present invention encodes an input video signal by layering it into N (N is an integer of 2 or more) hierarchal in resolution in the spatial axis direction. A hierarchical decoding device for a hierarchical encoding device that outputs a compressed bit stream by decoding, wherein N compressed video bit streams output from the hierarchical encoding device are decoded for each layer. It has a signal layer type decoding unit, and has (N-1) number of resolution converters for adjusting resolution between layers, and the resolution converters use FIR filters independently in the horizontal and vertical directions. The filter characteristic includes a band emphasis effect.

Further, the video signal transmission system using the hierarchical encoding device and the hierarchical decoding device of the present invention converts, for example, an input video signal to a low resolution in the spatial axis direction and outputs it ( N-1) types of first resolution converters, N types of high-efficiency encoders for performing a predetermined high-efficiency encoding on each of the N hierarchical signals to generate a compressed bit stream, and the minimum resolution (N
-1) a (N-1) second resolution converter for converting a signal encoded and decoded by a high-efficiency encoder of one layer to a higher resolution of one layer and outputting the same; A layered encoding device that outputs a layered compressed bit stream;
N types of high-efficiency decoding that perform high-efficiency decoding, which is the inverse transform of the high-efficiency encoding performed by the hierarchical encoding device, for each of the N-layer compressed bit streams output from the hierarchical encoding device From the lowest resolution layer (N-
1) a third resolution converter of (N-1) type which converts a signal output from the high-efficiency decoder of a hierarchy to a higher resolution by one hierarchy and outputs the converted signal; And a (N-1) th type of third resolution converter, selectively using the output signal of the third resolution converter to output an N-level decoded video signal. Using a predetermined transmission protocol to transmit a compressed bit stream of N layers, wherein the (N-1) third resolution converters provided in the hierarchical decoding device are: , FIR independently in horizontal and vertical directions
A filter is used, and the filter characteristic includes a band emphasis effect.

Further, the video signal transmission system using the hierarchical coding device and the hierarchical decoding device of the present invention converts, for example, an input video signal to a low resolution in the spatial axis direction and outputs it ( N-1) types of first resolution converters, N types of high-efficiency encoders for performing a predetermined high-efficiency encoding on each of the N hierarchical signals to generate a compressed bit stream, and the minimum resolution From the hierarchy of (N-
1) The signal encoded and decoded by the high-efficiency encoder of the hierarchy is resolution-converted to a higher resolution by one hierarchy and output (N
-1) a hierarchical encoder having a second type of second resolution converter and outputting a compressed bit stream of N layers, and a compressed bit stream of N layers output from the hierarchical encoder, N types of high-efficiency decoders for performing high-efficiency decoding, which is an inverse transform of high-efficiency coding performed by the hierarchical coding device, and (N-1)
A (N-1) third type of signal that outputs a signal output from a high-efficiency decoder of a hierarchy to a higher resolution by one hierarchy and outputs the converted signal.
, And selectively using the output signal of the highest resolution among the high-efficiency decoders and the output signal of the (N-1) third resolution converter. And a hierarchical decoding device that outputs a decoded video signal of
A system for transmitting a layered compressed bit stream using a predetermined transmission protocol, wherein said (N-1) second resolution converters provided in said layered encoding device are arranged in horizontal and vertical directions. An FIR filter is used independently for each direction, and the filter characteristics include a noise canceling effect.

Also, the video signal transmission system using the hierarchical coding device and the hierarchical decoding device of the present invention converts, for example, an input video signal to a low resolution in the spatial axis direction and outputs it ( (N-1) types of first resolution converters, N types of high efficiency encoders for performing a predetermined high efficiency coding on each of the N hierarchical signals to generate a compressed bit stream, (N-1) types of second resolution converters for converting the video signals generated by the (-1) types of first resolution converters to a higher resolution by one layer and outputting the same, and having N layers A hierarchical coding device that outputs a compressed bit stream, and inverse conversion of high-efficiency coding performed by the hierarchical coding device on each of the N-layer compressed bit streams output from the hierarchical coding device. N for efficient decoding And a signal which is an output of the high-efficiency decoder of the (N-1) th hierarchy from the lowest-resolution hierarchy and the resolution of the (N-1) th hierarchy is converted to a higher resolution by one hierarchy and outputted (N-1). A third resolution converter of the type, and selectively using an output signal of the highest resolution among the high-efficiency decoders and an output signal of the (N-1) third resolution converter. A system for transmitting a compressed bit stream of N layers using a predetermined transmission protocol by using a hierarchical decoding device that outputs a decoded video signal of N layers. (N-
1) A third type of resolution converter uses an FIR filter independently in the horizontal and vertical directions, and the filter characteristic includes a band emphasis effect.

Further, the video signal transmission system using the hierarchical coding apparatus and the hierarchical decoding apparatus of the present invention converts, for example, an input video signal to a low resolution in the spatial axis direction and outputs it ( (N-1) types of first resolution converters, N types of high efficiency encoders for performing a predetermined high efficiency coding on each of the N hierarchical signals to generate a compressed bit stream, (N-1) types of second resolution converters for converting the video signals generated by the (-1) types of first resolution converters to a higher resolution by one layer and outputting the same, and having N layers A hierarchical coding device that outputs a compressed bit stream, and inverse conversion of high-efficiency coding performed by the hierarchical coding device on each of the N-layer compressed bit streams output from the hierarchical coding device. N for efficient decoding And a signal which is an output of the high-efficiency decoder of the (N-1) th hierarchy from the lowest-resolution hierarchy and the resolution of the (N-1) th hierarchy is converted to a higher resolution by one hierarchy and outputted (N-1). A third resolution converter of the type, and selectively using an output signal of the highest resolution among the high-efficiency decoders and an output signal of the (N-1) third resolution converter. A system for transmitting a compressed bit stream of N layers using a predetermined transmission protocol by using a hierarchical decoding device that outputs a decoded video signal of N layers. (N-
1) A type of second resolution converter uses an FIR filter independently in the horizontal and vertical directions, and the filter characteristic includes a noise canceling effect.

The filter used for encoding and the filter used for decoding emphasize the reproducibility of the signal.
It is common sense to use the same, but the inventor
By changing the idea, by using these two filters with different characteristics,
The inventors of the present invention have invented a hierarchical coding apparatus and a hierarchical decoding apparatus that have a remarkable effect as described above and are easy to implement.

[0123]

According to the present invention, a hierarchical coding apparatus, a hierarchical decoding apparatus, a video signal transmission system, and a medium are characterized in that noise cancellation for improving subjective image quality can be performed without adding hardware. , And an information aggregate.

According to the present invention, a hierarchical coding apparatus, a hierarchical decoding apparatus, a video signal transmission system, a medium, and a medium are characterized in that edge enhancement for improving subjective image quality can be performed without adding hardware. An information aggregate can be provided.

[Brief description of the drawings]

FIG. 1 is a block diagram of a video signal hierarchical decoding transmission apparatus according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a video signal transmission system using a hierarchical encoding device and a hierarchical decoding device according to Embodiment 2 of the present invention.

FIG. 3 is a block diagram of a video signal transmission system using a hierarchical encoding device and a hierarchical decoding device according to a third embodiment of the present invention.

FIG. 4 is a block diagram of a video signal transmission system using a hierarchical encoding device and a hierarchical decoding device according to Embodiment 4 of the present invention.

FIG. 5 is a block diagram of a video signal transmission system using a hierarchical encoding device and a hierarchical decoding device according to a fifth embodiment of the present invention.

FIG. 6 shows a low-resolution video signal and enhancement.
Explanatory drawing of the passband of the layer (FIG. 6A), FIG.
The filter characteristics of the FIR filter of the second resolution converter 401 and the filter characteristics of the second resolution converter 401 (FIG. 6)
(B)) Filter characteristics of the FIR filter of the resolution converter 103 and the FIR filter of the third resolution converter 206 (FIG. 6C)

FIG. 7 shows a low-resolution video signal and enhancement.
Explanatory drawing of the passband of the layer (FIG. 7A), FIG.
FIG. 7B shows the filter characteristics of the FIR filter included in the resolution converter 301 and the FIR filter included in the second resolution converter 501, and the third resolution converter 302.
FIG. 7 shows the filter characteristics of the FIR filter included in FIG.
(C)), a characteristic diagram of the decoded video signal output from the adder 104 (FIG. 7 (d))

FIG. 8 is a block diagram of a video signal transmission system using a conventional hierarchical coding device and a hierarchical decoding device.

[Explanation of symbols]

101,806 First high-efficiency decoder 102,807 Second high-efficiency decoder 103 Resolution converter 104,809 Adder 201,801 First resolution converter 202,802 First high-efficiency encoding Devices 203, 301, 401, 501, 803 second resolution converters 204, 804 difference signal generators 205, 805 second high-efficiency encoders 206, 302, 808 third resolution converter 810 edge detector 811 Edge enhancer

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H04N 7/081 F-term (Reference) 5C021 PA31 PA38 YA01 YC08 5C059 KK01 MA00 MA32 PP00 RB00 SS11 SS20 UA02 UA05 UA11 UA39 5C063 AB03 AB05 CA12 CA21 5J064 AA02 BB07 BC02 BC08 BC11 BD02 BD03

Claims (9)

[Claims] A first resolution conversion unit that hierarchizes an input video signal into N (N is an integer equal to or greater than 2) resolutions; N encoding means for generating and outputting a plurality of compressed bit streams, respectively, and a filter for converting the resolution of the hierarchized video signal using indirectly or directly, and outputting a video signal And a filter characteristic of the filter is set so as to cancel noise included in the video signal subjected to the resolution conversion, and the N video signals hierarchized are provided. Encoding means for encoding the video signal of at least the highest layer, when generating the compressed bit stream, the output from the second resolution conversion means A video signal, the hierarchical coding apparatus characterized by the use on the basis of a predetermined criterion. 2. The encoding means decodes the generated compressed bit stream by encoding the hierarchized video signal, and converts a video signal obtained by the decoding into a second video signal. The resolution conversion using the hierarchized video signal indirectly means that the resolution of the video signal obtained by the decoding of the compressed bit stream is converted. 2. The hierarchical coding apparatus according to claim 1, wherein: 3. The resolution conversion of the hierarchized video signal directly means that the hierarchized video signal itself is resolution-converted by the first resolution conversion means. The hierarchical encoding device according to claim 1. 4. An input from an hierarchical encoding device that outputs N compressed bit streams by layering and encoding an input video signal into N (N is an integer of 2 or more) resolutions. A decoding apparatus for receiving the N compressed bit streams and decoding each of the layers, and a video signal decoded for each of the layers Has a filter for adjusting the resolution between the layers (N-
1) third resolution conversion means, wherein the filter characteristics of the filter are set so as to emphasize a predetermined frequency band of the video signal decoded for each layer. Hierarchical decoding device. 5. A layered encoding device that outputs N compressed bit streams by layering and encoding an input video signal into N (N is an integer of 2 or more) resolutions, and (N) decoding means for inputting the compressed bit stream of each layer and decoding each layer, and a filter for adjusting the resolution between the layers of the video signal decoded for each layer ( N-
1) third resolution converting means, wherein filter characteristics of the filter are set so as to emphasize a predetermined frequency band of the video signal decoded for each layer. A video signal transmission system, comprising: a device; 6. A first resolution conversion means for layering an input video signal into N layers (N is an integer of 2 or more) with respect to resolution; N encoding means for generating and outputting a plurality of compressed bit streams, respectively, and a filter for converting the resolution of the hierarchized video signal using directly or indirectly and outputting a video signal And a filter characteristic of the filter is set so as to cancel noise included in the video signal subjected to the resolution conversion, and the N video signals hierarchized are provided. Encoding means for encoding the video signal of at least the highest layer, when generating the compressed bit stream, the output from the second resolution conversion means A hierarchical coding device that uses a video signal based on a predetermined criterion, N decoding units that receive the N compressed bit streams and decode each of the layers, It has a filter for adjusting the resolution of the decoded video signal between layers (N-
1) a hierarchical decoding device having three third resolution conversion means; and a video signal transmission system comprising: 7. A first resolution conversion means for hierarchizing an input video signal into N (N is an integer of 2 or more) resolutions, and encoding the hierarchized video signal to obtain N N encoding means for generating and outputting a plurality of compressed bit streams, respectively, and a filter for converting the resolution of the hierarchized video signal using directly or indirectly and outputting a video signal And a filter characteristic of the filter is set so as to cancel noise included in the video signal to be resolution-converted, and the N number of hierarchical video signals are provided. Encoding means for encoding the video signal of at least the highest layer, when the compressed bit stream is generated, the output from the second resolution conversion means A video signal, a hierarchical coding apparatus that uses the video signal based on a predetermined criterion, N decoding means for inputting the N compressed bit streams and decoding each of the layers, It has a filter for adjusting the resolution of the decoded video signal between layers (N-
1) third resolution conversion means, wherein the filter characteristics of the filter are set so as to emphasize a predetermined frequency band of the video signal decoded for each layer. A video signal transmission system, comprising: a device; 8. A medium carrying a program and / or data for causing a computer to execute all or a part of the functions of all or part of the present invention according to any one of claims 1 to 7. A medium which can be processed by a computer. 9. A program and / or data for causing a computer to execute all or a part of the functions of all or a part of the present invention according to any one of claims 1 to 7. Information aggregate to do.