JPH10215449A - Signal processing unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize the digital moving image compressor with high image quality and a small delay. SOLUTION: An interlace image signal is given to a compression unit configuration means 201 from a terminal 211, in which a compression unit in response to coding whether depending on a field structure or a frame structure is configured. In the case of the frame structure, a changeover means 214 switches a signal in the frame or field compression unit stored and configured in an image storage means 212 and gives to a macro block configuration means 215. In the case that the compression unit is fixed to a field structure, the changeover means 214 selects an interlace image signal from the input terminal 211 and gives directly the signal to the macro block configuration means 215. Thus, in this case, almost no delay is produced. The macro block configuration means 215 rearranges information for each macro block and the result is outputted from a terminal 216, the information is compression-coded by a compression means and converted into a bit stream at a prescribed rate by a smoothing means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing apparatus for encoding digital video signals with high efficiency, and more particularly to a signal processing apparatus for performing compression and decompression with low delay (that is, with a small delay time). .

[0002]

2. Description of the Related Art As a conventional example of means for compressing a moving image, for example, "ITU-T White Book, Audiovisual / Multimedia-Related (H Series) Recommendations" (Japan ITU Association, February 1995) The moving image compression standard H.262 (commonly referred to as MPE) defined in pp. 375-595 (hereinafter referred to as Document 1)
G2 method).

In the MPEG2 system, a moving image signal of an interlace system, which is a moving image transmission and display system widely used at present, is also assumed to be compressed, and high-efficiency compression is performed in units of frames or fields which are image constituent units. It is made possible.

[0004] An interlaced moving image signal is composed of a field image input at a constant period (for example, 1/60 second). The field images are arranged such that the scanning line positions are shifted from each other in a cycle of two images, and all the scanning lines are covered by two fields. A combination of these two fields is called a frame. In an interlaced moving image signal, images are sequentially transmitted in field units.

FIG. 37 shows an example of the scanning order of the frame, that is, the transmission order of the pixel information constituting the frame. As shown in FIG. When the scanning is performed as indicated by the solid arrow at 1, the scanning is performed at the field 2 as indicated by the dashed arrow following the scanning of the field 1. Therefore, in the frame in which these fields 1 and 2 are combined, if the scan indicated by the solid arrow is performed on the field 1, then the scan on the field 2 is performed during the scan of the field 1 as indicated by the broken arrow. Will be. Then, the image information of the frame is also transmitted in this order.

[0006] In the MPEG2 system, p. As described in “I.4.1.2 Encoding Interlaced (Interlaced Scanning) Images” at 379, both field-based compression coding and frame-based compression coding are possible, It is also possible to mix both in one stream.

Next, a general procedure of moving picture compression by the MPEG2 system will be described.

First, an image compression unit consisting of a frame or a field is formed from an input interlaced image signal. An image serving as an image compression unit (hereinafter referred to as a compression unit image) is a field or frame image,
These unit images are divided into blocks (that is, macroblocks) of 16 × 16 pixels in the horizontal and vertical directions, and processing is sequentially performed in the horizontal direction from the macroblock at the upper left corner of the screen in the same manner as in the above scanning order.

An interlaced image which is an input moving image is
As described with reference to FIG. 37, first, pixel information of field 1 is sequentially input by one line (one horizontal scanning period) from the upper left corner of the screen, and then pixel information of field 2 is sequentially input by one line from the upper left corner of the screen. Is entered. When a frame is used as an image compression unit, pixel information of field 1 is stored, and when pixel information of the first eight lines of field 2 is input, first 16 × 16 pixel information of the eight lines is input. And the first 16 × of the first 8 lines of field 1
The first macroblock is composed of 16 pixel information.

For this reason, there is a delay corresponding to approximately one field period plus eight lines from the start of input of an interlaced image signal to the formation of the first macroblock of a frame which is a unit of image compression. Even when the unit image is a field image and it is not necessary to form a frame, a method of forming a unit image with a delay of one field is employed in order to match the image compression and signal processing timing in frame units. .

[0011] Next, for a field macroblock or a frame macroblock as a compression unit, MP
Processing is performed so as to be a signal defined in the EG2 system, and image compression is performed. In the MPEG2 system, digital moving image information is compressed by using the redundancy of moving image information and human visual characteristics and deleting redundant information and information that is not important for human visual characteristics. The code amount of digital information (bit stream) obtained as a result of compression greatly varies depending on the characteristics of an input image, for example, the correlation between frames or fields and the amount of high spatial frequency components even under the same compression conditions. Therefore, the code amount obtained as a result of compression changes every moment during one frame period or one field period which is a compression unit. In general, a target of the code amount is determined for each frame or field that is a compression unit, and the compression parameter is controlled so that the code amount matches the target.

In order to transmit such a stream via a transmission line having a constant data transfer rate, during a period in which the code amount is large, codes exceeding the transmission capacity are stored in a buffer to limit the transmission amount. During the period when the amount is small, it is necessary to take out the code from the buffer and transmit it at a predetermined data transfer rate. Such a process is called a smoothing process. In order to perform such a smoothing process, a certain amount of information is stored in advance on the transmission side, and transmission can be performed at a constant speed even if the generated code amount changes. Further, it is necessary to prepare a buffer on the receiving side so that decoding can be continued even if the code amount required for decoding changes. By providing one or more pictures of the delay time by the buffer, it is possible to cope with a case where the code amount distribution is largely biased within a picture or between pictures.

Further, in the MPEG2 system, as described in “Image Buffer Verifier” of pp. 531 to 535 of Document 1, low delay is realized even if an image having a large code amount exists. As a technique for performing the encoding, it is possible to skip and encode several images subsequent to the image having a large code amount, and to compress the subsequent images so that the delay amount is reduced. Hereinafter, this processing is referred to as a picture skip, and an image having a large code amount that causes the picture skip is referred to as a large image.

For example, if there is an image compressed to a code amount twice as large as the code amount of a standard image derived from the transfer rate, to transmit the code of this image,
It requires transmission time for an image. Therefore, even if a subsequent image is compressed to a code amount that matches the transfer rate, the transmission time is delayed by one image time. In order to solve this problem, an image immediately after an image having a large code amount is skipped and compression is performed to prevent a long delay from continuing.

[0015]

The MPEG2 system is also expected to be used for digital television broadcasting and video conferences. In these applications, the transfer rate of the transmission path is fixed, and the time required from the input of the moving image signal on the transmitting side to the output of the reproduced signal on the receiving side (hereinafter referred to as compression / decompression delay) is short. Is more desirable. Therefore, compression,
It is desired that the processing delay is small even during the extension process.
The compression process has the following problems.

As described in the above prior art, MPEG
In the two methods, since a frame image is formed from an interlaced image that is an input moving image, a delay time corresponding to one field time is generated. This delay causes an increase in the compression / decompression delay.

A first object of the present invention is to provide a signal processing device capable of reducing a delay time when forming a frame image.

Further, a buffer for smoothing the data transfer rate also causes an increase in the compression / decompression delay. Since the code amount of the compressed data is often controlled by setting the target of the code amount for each field or frame which is the compression unit, the distribution of the bit amount in the compression unit is determined by the input image. It depends greatly on. Even if codes are concentrated at the end of an image, it is necessary to store data for one compression unit image in a buffer before sending it to the transmission path in order to continue stream output without interruption. There was a delay of more than a unit.

As a conventional example of reducing the buffer delay,
For example, JP-A-5-316498 (hereinafter referred to as Document 2)
It is known that encoding is performed by deciding a code amount distribution within a compressed unit image so that a code amount generated from the image compressed unit image does not deviate from a target value. However, this conventional example merely realizes that the code amount of one compression unit image is contained within a predetermined value with a small error, and the delay caused by the smoothing buffer is reduced by one.
It is not assumed to be shorter than the compression unit.

Accordingly, a second object of the present invention is to provide a signal processing device capable of further reducing the delay caused by such smoothing.

Further, the picture skip function used as a method for preventing an increase in delay in the MPEG2 system has a problem that the image quality immediately after skipping is deteriorated.
A large image that causes a skip picture is likely to occur in an I picture defined by the MPEG2 system. However, in the field structure of the MPEG2 system (a field image is a picture), when a field image in the first half of a frame configuration is compressed as an I picture, The latter half of the field is I
The picture is restricted to a P picture that refers to only an I picture that has been compressed immediately before.

Further, the MPEG2 system specifies that a skip picture must be skipped for a time corresponding to a multiple of two fields. That is, the picture immediately after the skip is temporally separated from the picture immediately before the skip, and has a different scan line position. Therefore, if the I picture is a large image in the field structure and the next image to be encoded is a P picture that refers only to this, the P picture uses a temporally distant image as a reference image, and Since the reference image and the scanning line position are different, there is a high possibility that the difference between the reference image and the reference image is large, and there is a high possibility that the compression efficiency and the image quality will decrease.

Accordingly, a third object of the present invention is to provide a signal processing device capable of preventing such compression efficiency and image quality deterioration.

In the extension process, there are the following problems. In the MPEG2 system, compression in a frame structure is also possible. In order to output an image obtained by expanding compressed information compressed as a frame structure as an interlace image, it is necessary to convert the frame image into an interlace image. Yes, this process results in a processing delay of approximately one field. Even in the case of the field structure, it is necessary to match the processing delay in order to obtain a continuous reproduced image from the image decompressed from the frame structure, which also requires a delay of one field.

Accordingly, a fourth object of the present invention is to provide a signal processing device capable of reducing such a delay.

Since the code amount distribution for each macroblock in a frame or field, which is a compression unit, is arbitrary, when compressing compressed information transferred at a constant rate, the data constituting the compression unit is compressed. It is necessary to start the decompression processing after receiving all of them. For this reason, there is a delay corresponding to the transfer time of the compression unit from the reception of the head data of the compression unit to the start of the decompression process.

Accordingly, a fifth object of the present invention is to provide a signal processing device capable of reducing such a delay.

[0028]

As a means for solving these problems, the present invention has devised a method of controlling the processing timing associated with compression and smoothing by a unique method.

That is, in order to achieve the first object,
The present invention sets a mode in which the compression unit is limited to only the field image. In a conventional compression device based on the MPEG2 system, since the compression unit is allowed to be both a frame image and a field image, even if the compression unit is only a field image as a result, a frame image is formed. A delay time approximately equal to the time required for However, by performing compression while fixing the compression unit to the field image as in the present invention, when the compression unit is only the field image, it is possible to eliminate the delay time associated with forming the frame image. Become. As a result, before the last piece of the image information constituting the field image is input to the compression unit forming means, it is possible to output the head part of the image compression unit consisting of the field image from the compression unit forming means. .

In order to achieve the second object, the present invention provides a method for compressing a stream so that a stream can be output without interruption even if reading from a smoothing buffer is started before image input in a compression unit is completed. The compression is performed in consideration of the bit allocation in the unit. As a result, before the last piece of image information constituting the compression unit is input to the compression means, it is possible to output the head of data obtained as a result of compressing this image compression unit from the smoothing means, It is possible to reduce a delay of one compression unit or more due to the data transfer rate smoothing.

In order to achieve the third object, the present invention does not start skipping from the image immediately after the large image, but compresses one or more images immediately after the large image and skips subsequent images. I do. When a skip picture is caused by a large image, a temporal reference (temporal_reference: a number indicating the display order of pictures) in the compressed image immediately after the large image by the MPEG2 method.
Needs to be discontinuous with the large image, the temporal_reference of the image to be compressed immediately after the large image is appropriately replaced. Since the image compressed immediately after the large image set in this way is an image temporally close to the reference image, the deterioration of the image quality is reduced as compared with the conventional method. In addition, since the code of this image has a time margin from the input of the image to the output of the stream, it is possible to allocate an additional code associated with the skip to this image. As a result, it is possible to reduce image quality degradation of an image compressed immediately after a large image.

In order to achieve the fourth object, according to the present invention, at the time of compression, information indicating that a predetermined set of compression units is composed of only a field structure is added, and this information is added only to the field structure. , The processing delay associated with the conversion from the frame structure to the interlaced image is eliminated. By performing such processing, it is possible to reduce delay without causing discontinuity at the boundary between the field structure and the frame structure.

Alternatively, even if there is no information indicating that the frame structure is composed of only the field structure, the field structure is expanded by removing the delay caused by the conversion from the frame structure to the interlaced image. The decompression is performed by inserting a delay due to the conversion from an image into an interlaced image and an appropriate delay, and at the boundary between the two, a process of maintaining continuity by using image repetition or thinning is performed. By performing such processing, it is possible to perform decompression with a small delay in the field structure.

As described above, at the time of decompression, the delay of one field due to conversion from a frame structure to an interlaced image can be reduced.

To achieve the fifth object, according to the present invention, at the time of compression, information indicating the decompression start time of the compression unit is added according to the data transfer rate, and the compression unit is added based on the time information. The reproduction is started even before the reception of the last information. If the decompression is started from this decompression start time, the decompression process is performed without interruption because the compression is performed in consideration of the code distribution in the compression unit so that decompression can be performed continuously. it can. In this way, it is possible to reduce the delay at the time of decompression due to buffering of the compression unit.

[0036]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing a first embodiment of a signal processing apparatus having a moving image information compression function according to the present invention, wherein 101 is an input terminal of an image signal, 201 is a compression unit constituting unit, 301 is a compression unit, Reference numeral 401 denotes a smoothing unit; 501, an output terminal of a compressed signal; and 506, an output terminal of a flag (hereinafter, referred to as a field structure flag) indicating that all predetermined compression unit sets have a field structure.

In the first embodiment, the frame / field structure can be switched as a compression unit, and when the compression unit is fixed to the field structure, the compression unit can be configured with a smaller delay time. Is what makes it possible. If the field structure is fixed, a field structure flag can be inserted into the compressed information or output to the outside.

Next, the operation of the first embodiment will be described.

In FIG. 1, a moving image signal to be compressed is input from an input terminal 101 as an interlaced image signal. This interlaced image signal is subjected to predetermined processing by the compression unit forming means 201 to form a group of macroblocks defined by the MPEG2 system.

Here, a specific example of the compression unit constituting means 201 will be described with reference to FIG. 1, reference numeral 211 denotes an input terminal connected to the input terminal 101 in FIG. 1, reference numeral 212 denotes an image storage means, reference numeral 213 denotes an address generation means, reference numeral 214 denotes a low-delay / normal-delay switching means, and reference numeral 215
216 is a terminal connected to the compression means 301 in FIG. 1, 217 is an output terminal 5 in FIG.
06 is a terminal connected to this terminal.

As in the conventional case, in the case of a normal delay operation in which a frame structure and a field structure are arbitrarily selected and compression encoding is performed, the switching means 214 selects the output of the image storage means 212. The moving image information input as an interlaced image signal from the terminal 211 is stored in the image storage unit 212 in the order of field 1 and field 2.

When the moving image information is compressed in a frame structure, when the information necessary for forming the frame image is input, that is, the image input in the field 1 is completed and the image in the field 2 is input. The frames are sequentially output in frame order from the time when the input is started. Since one frame period is required until the output is completed, the output of the image of one frame is completed is almost equal to the time when the image input of the field 1 of the next frame is completed. On the other hand, since the signal must be continuous with the preceding and succeeding frames also in the compression period as the field structure, the image input of the field 1 is completed and the image input of the field 2 is started. And the image information of field 2 are output.

The image information rearranged in the frame or field structure in this manner is rearranged into information for each macroblock by the macroblock structuring unit 215 and sent from the terminal 216 to the compression unit 301 in FIG. ,
It is converted into a predetermined code defined by the MPEG2 system. At this time, if necessary, the field structure flag is set to M
It is inserted into the user data defined by the PEG2 system. Since 16 lines of information are required to construct a macroblock, the macroblock constructing means 215 (FIG. 2)
Is approximately equivalent to the time for 16 lines. However, this time is much shorter than the time corresponding to the field minutes.

FIG. 3 is a timing chart showing an example of input / output timing of the compression unit constituting means 201 (FIG. 2) in the normal delay state described above, where 801 is an input image signal from the terminal 211, and 802 is The macroblock signal output from the terminal 216 is shown for each field or frame. “Frm” represents a frame, and “Fld” represents a field.

In this example, the frame Frm3 is compressed as a field structure, and the frames 1, 2, 4 are compressed as a frame structure. In both the frame structure and the field structure, a delay of one field period or more occurs between the input image signal 801 and the output macroblock signal 802.

On the other hand, in FIG. 2, in the case of a low-delay operation in which the delay time is reduced by fixing the field structure, the switching means 214 selects the input image signal from the terminal 211. At this time, a field structure flag is output from the terminal 217 as necessary. In this state, a moving image signal input in the field order as an interlaced image signal is supplied to the macroblock forming means 215 as it is, and is converted into a macroblock having a field structure. This macro block signal is supplied from a terminal 216 to the compression means 3 in FIG.
01 and is converted into a predetermined code defined by the MPEG2 system. At this time, if necessary, a field structure flag is inserted into user data defined by the MPEG2 system.

FIG. 4 is a diagram showing an example of the input / output timing of the compression unit constituting means 201 in such a low delay state, and the signals corresponding to FIG. 3 are denoted by the same reference numerals.

In the figure, in the low delay state, all input images are compressed as a field structure. The processing delay time in this case is much smaller than one field time.

FIG. 5 is a block diagram showing a conventional example (hereinafter, referred to as a first conventional example) of a signal processing device having a moving image information compression function. Are assigned the same reference numerals. FIG. 6 is a block diagram showing the structure of the compression unit forming means 201 'in FIG. 5, and the same reference numerals are given to portions corresponding to FIG.

As is apparent from a comparison between FIGS. 1 and 2 and FIGS. 5 and 6, the first embodiment differs from the first conventional example in that the compression unit forming means 201 is different from the compression unit forming means 201 in FIG. 20
1 ′ is provided with a function of supplying an interlaced image signal directly input to the macroblock forming unit 215.

That is, the delay in the normal delay state of the first embodiment (FIG. 3) corresponds to the delay in the first conventional example.
As can be seen from a comparison between FIG. 4 and FIG. 3, in the case of the first conventional example (FIG. 3), the last information of each of the fields (field 1 or field 2 in frame 3) as the image compression unit is Before being input to the image unit composing unit 201, it is impossible to output from the compression unit composing unit 201 the head part of the signal in which each field is recomposed into the image compression unit. In the low-delay state in the embodiment (FIG. 4), before the last information of each field, which is an image compression unit, is input to the image unit composing unit 201, a signal in which each field is reconfigured into an image compression unit Can be output from the compression unit composing means 201. Therefore, in the first embodiment, it is possible to reduce the delay time corresponding to approximately one field as compared with the conventional method.

FIG. 7 is a block diagram showing a second embodiment of a signal processing apparatus having a moving image information decompression function according to the present invention. In FIG. 7, reference numeral 102 denotes an output terminal of an image signal; Decompression means, 402 is a data transfer rate conversion means, 502 is an input terminal for a compressed signal, and 507 is an input terminal for a field structure flag.

The second embodiment makes it possible to configure an interlaced image with a smaller delay time when the compression unit is only a field structure.

In FIG. 7, a moving picture compression code signal transferred at a predetermined transfer rate is input from a terminal 502 and is converted by a data transfer rate conversion means 4 until the data length becomes an extendable data length.
02. This signal is supplied to MP
The data is expanded by a decompression procedure specified in the EG2 system and converted into a macroblock signal. At this time, if the field structure flag is included in the user data of the code, it is also expanded and output. The interlaced image forming unit 202 forms an interlaced image from the macroblock signal.

FIG. 8 is a block diagram showing a specific example of the interlaced image forming means 202 in FIG.
Numeral 31 denotes a terminal for inputting a macroblock signal from the decompression means 302 in FIG. 7; 232, a scanning line forming means for forming a scanning line having a field or frame structure from the macroblock signal; 233, an image storage means; Read address generation means, 244 is a low delay / normal delay switching means, 235 is a terminal connected to the image output terminal 102 in FIG. 7, 241 is a terminal for inputting a field structure flag developed by the decompression means 302 in FIG. 7, Reference numeral 242 denotes a terminal for inputting a field structure flag input from the outside, 243 denotes a flag switching unit, 244 denotes a low delay / normal delay switching unit, and 245 denotes a frame number adjusting unit.

In the figure, the macroblock signal input from the terminal 231 is accumulated in the scanning line forming means 232 until the information of the scanning line is completed, and at the time when the information is completed, the frame order is determined according to the compressed structure. Or output in field order. This output signal is stored in the image storage means 233 in frame order or field order. When the compression unit has a frame structure, the image storage unit 233 changes the reading order so as to be in the field order of the interlaced image and outputs the image. At this time, since the frame image is converted into the field image, a delay of one field occurs. If the compression unit has a field structure, the data is output without changing the reading order. At this time, in order to enable continuous output with the frame image, output is performed with a delay of one field. An address is generated by the address generation means 234 so as to realize such reading / writing.

When the field structure flag exists in the bit stream or when an equivalent signal is input from the external terminal 507, the selecting means 2 shown in FIG.
43, the field structure flag to be used is selected. If this flag indicates that only the field structure is used, the switching unit 244 switches the scanning line configuration unit 2
Select 32 outputs. Therefore, since the signal output from the terminal 235 does not include the delay due to the interlacing, an image obtained by expanding the head of the same frame before the last compression unit belonging to the same field is input to this embodiment. The output can be made from the interlaced image forming means 202.

On the other hand, if these flags do not exist,
Alternatively, when it indicates that a frame structure is included, the switching unit 244 selects the output of the image storage unit 233. This output is delayed by one or more fields with respect to the input.

FIG. 9 is a block diagram showing a second conventional example of a signal processing apparatus having a moving picture information decompression function.
Reference numeral 2 'denotes an interlaced image forming means, and portions corresponding to those in FIG. 7 are denoted by the same reference numerals. FIG. 10 is a block diagram showing an example of the interlaced image forming means 202 'in FIG. 9, and portions corresponding to those in FIG.

As is apparent from a comparison of FIGS. 7 and 8 with FIGS. 9 and 10, the second embodiment differs from the second conventional example in that an This corresponds to a configuration in which the function of outputting the output from the scanning line forming unit 232 to the terminal 235 is provided to the image forming unit 202 ′.

FIG. 11 is a diagram showing an example of input / output timing in the interlaced image forming means 202 (FIG. 8) in the second embodiment, and FIG. 12 is a diagram showing the interlaced image forming means 202 in the second conventional example. '(Fig. 1
FIG. 3 is a diagram showing an example of input / output timing at 0). In the figure, reference numerals 851 and 853 denote macroblock signals input to the interlaced image forming means 202 for each field, and 852 and 854 denote interlaced image signals output from the interlaced image forming means 202 for each field. It is shown, and the notation conforms to FIG.

In this example, the macroblock signal 851 and the output interlaced image signal 852 have all compression units fixed in a field structure, and have reduced delay for conversion to an interlaced image signal. , The macroblock signal 853 and the output interlaced image signal 854 have a mixture of a frame structure and a field structure.

As can be seen from the comparison between FIG. 11 and FIG.
In the conventional example shown in FIG. 12, the last information of each of the fields (field 1 or field 2 of frame 3) as the image compression unit is the
Before input to 2 ′ (FIGS. 9 and 10), it is impossible to output from the interlaced image forming means 202 ′ the head of the image signal in which each of these fields is reconfigured in image compression units. On the other hand, in the low delay state (FIG. 11) of the second embodiment, the last information of each field which is a unit of image compression is input to the interlaced image forming means 202 (FIGS. 7 and 8). The interlaced image forming means 202 can output the head of the image signal in which each of these fields has been reconfigured in units of image compression before the image signal is compressed. Therefore, according to the second embodiment, it is possible to reduce the delay time corresponding to approximately one field as compared with the above-described conventional method.

In the second embodiment, even when there is no field structure flag or when it indicates that a frame structure is included, the frame number adjusting means 245 (FIG. 8) uses the field structure and the frame structure. In this case, the number of frames at the point of change is adjusted to convert the image into a continuous image, whereby an interlaced image signal having a low delay can be output in the field structure.

FIGS. 13 and 14 show examples of input and output of the interlaced image forming means 202 in this case.
Reference numeral 55 denotes a macroblock signal input to the interlaced image forming unit 202, and reference numeral 856 denotes an interlaced image signal output from the interlaced image forming unit 202 for each field.

FIG. 13 shows an example in which two fields are repeated when transitioning from the field structure to the frame structure, and two fields are skipped when transitioning from the frame structure to the field structure. In this example, in the field structure, the delay can be kept within one field, and the delay in the frame structure increases to two or more fields, but the field order is not disturbed even at the connection point of both. There is.

On the other hand, FIG. 14 shows an example in which one field is repeated when transitioning from the field structure to the frame structure, and one field is skipped when transitioning from the frame structure to the field structure. In this example, the delay in the field structure can be less than one field, and the delay in the frame structure is
Although increasing to one or more fields, this value is equivalent to the delay in the conventional method.

FIG. 15 is a block diagram showing a third embodiment of the signal processing apparatus having a moving picture information compression function according to the present invention. In FIG.
Numeral 601 denotes a control means, and portions corresponding to those in FIG.

In the third embodiment, FIG.
It has a function of controlling the amount of generated codes in the compression means 301 in consideration of the delay time from when the head of the compression unit is input to the compression means 301 to when the corresponding data is output from the smoothing means 401. Even if the delay time from when the head of the compression unit is input to the compression unit 301 to when the corresponding data is output from the smoothing unit 401 is less than one compression unit time, the bit stream is output without interruption. In addition, even if the receiving side starts decompression before the receiving side accumulates one compression unit of the bit stream output from the smoothing means 401 at a constant transfer rate, In addition to performing the code amount control so as to ensure that the decompression start time information is inserted into the data stream or output from the terminal 508, Characterized in that it.

FIG. 16 is a block diagram showing a specific example of the control means 601 in FIG. 15, wherein 611 is timing calculation means, 612 is macroblock code amount distribution calculation means, and 613 is macroblock coding parameter calculation means. is there.

FIG. 17 is a block diagram showing a third conventional example of a signal processing apparatus according to the third embodiment. In FIG. 17, reference numeral 601 'denotes control means, and portions corresponding to those in FIG. The sign is attached. FIG. 18 shows FIG.
FIG. 17 is a block diagram illustrating an example of a control unit 601 ′ in FIG. 7, and portions corresponding to FIG. 16 are denoted by the same reference numerals.

In the third embodiment, as shown in FIG. 15, the image information input from the input terminal 101 is converted by the compression unit forming means 201 into the macroblock order determined by the MPEG2 system, , And further converted by the smoothing means 401 into a data transfer rate conforming to the specifications of the transmission path, and output from the output terminal 501.

The timing at which the bit stream is output from the smoothing means 401 is managed by the control means 601. In FIG. 16, the control means 601 determines that the compression means 301 in FIG. The stream output timing calculating means 611 calculates the time at which the bit stream is output from the smoothing means 401 at a predetermined timing including the time before the information is input, and instructs the smoothing means 401.

Also, the control means 601
After the head of the compression unit is input to
The code amount distribution of the macroblock is calculated by the macroblock code distribution calculation means 612 in consideration of the delay time until the corresponding data is output from the macroblock. Calculated by the encoding parameter calculating means 613,
To instruct. Also, if necessary, continuous decompression can be guaranteed even if decompression is started on the reception side before the bit stream output at a constant transfer rate from the smoothing means 401 is accumulated on the reception side for one compression unit. Then, while controlling the code amount, decompression start possible time information is inserted into the bit stream or output from the terminal 508 to the outside.

Although these control methods will be described later, the macroblock coding parameters include the quantization count, the order of the DCT coefficient to be coded, and the filtering process.

On the other hand, in the third conventional example shown in FIGS. 17 and 18, the macroblock code distribution calculating means 612 in the control means 601 'determines the code amount distribution without considering the output timing of the smoothing means 401. Compression means 301
Indicates the macroblock coding parameters.

Next, an example of control in the third embodiment and the third conventional example will be described with reference to FIG.

FIG. 19 shows a cumulative example of the code amount output from the compression means 301 in the third embodiment and the third conventional example,
5 shows a cumulative example of the code amount output from the smoothing means 401, in which the horizontal axis represents time and the vertical axis represents the cumulative amount of generated codes. Here, the unit of time represents the time of the compression unit (field or frame) as T, and the origin of the horizontal axis (time axis) is the time when the first compression unit is input to the compression unit 301. The delay associated with the compression process is negligible. In addition, the cumulative total of generated code amounts expresses an average allocated code amount per compression unit as B.

In the figure, the cumulative output 903 from the smoothing means 401 (FIG. 17) in the third conventional example is represented by a time T
The example which starts output from is shown. This condition is almost equivalent to starting the output from the smoothing means 401 when the input of the first compression unit to the compression means 301 is completed.

On the other hand, the cumulative output curve 904 from the smoothing means 401 (FIG. 15) in the third embodiment shows an example starting from time yT (where 0 ≦ y <1). This condition is satisfied before the image input to the compression unit 301 (FIG. 15) of the first compression unit is completed.
1 indicates that the output from 1 is started. The output cumulative example curve 904 can be expressed by the following equation.

B (t) = (t / T−y) B (1) where t> yT.

In FIG. 19, a curve 905 represents the total output from the smoothing means 401 when the possible decompression start time on the receiving side is set to 0. That is, the decompression start possible time means a time at which zT time has elapsed after the arrival of the code.

In FIG. 19, a curve 901 represents an example of the total code amount output from the compression means 301 (FIG. 17) in the third conventional example. In this example, 1
This is an example in which the code amount allocation is determined for each compression unit, and the code amount allocation within each compression unit is set irrespective of the bit stream output timing from the smoothing means 401 (FIG. 17). That is, in FIG. 19, (t, b) =
This is an example in which control is performed so as to pass through points (T, B), (2T, 2B),. The trajectory of the curve connecting these points varies depending on the characteristics of the input image.

The curve 901 is always above the curve 903, but is not always above the curve 904. This means that in the rate control according to the third conventional example, the output from the smoothing means 401 (FIG. 17) is started before the image input to the compression means 301 (FIG. 17) of the first compression unit is completed. Indicates that the smoothing buffer may cause underflow in the middle.

The curve 901 is not always below the curve 905. This means that if the decompression unit starts decompression at the time point of elapse of zT after receiving the head of this code, the code amount becomes insufficient during decompression. Even if the compression unit is divided into a plurality of blocks and the code amount is determined for each of the blocks as in the conventional example shown in the above-mentioned document 2, the code amount is determined based on the bit stream output timing yT from the smoothing buffer and the like. Unless the value reflects the compression unit expansion start possible time zT, there is a possibility that underflow of the smoothing buffer or insufficient data on the receiving side may occur.

On the other hand, a curve 902 in FIG. 19 shows an example of the total code amount output from the compression means 301 (FIG. 15) in the third embodiment. In this example, the code amount allocation is determined for each compression unit, and the lower limit of the generated code amount transition in each compression unit is smoothed by the smoothing means 401 (FIG. 1).
This is an example in which code amount control is performed in consideration of the output timing from 5) and the possible compression unit expansion start time on the expansion unit side.

In this example, the generated code amount is controlled so that the code amount of each compression unit satisfies the following expression. b (t)> (t / T−y) B (2) b (t) <(t / T + z) B (3)

By performing such control, the curve 902 is controlled within an area represented by a mesh in FIG. In this region, it is always above the curve 904,
And it is guaranteed that it is always below the curve 905.
Therefore, in the bit stream generated by performing such code amount control, the head of the compression unit is
After yT time from the input to (FIG. 15), the output from the smoothing buffer can be started. This means that even if the information of the compression unit is output from the smoothing buffer before the end of the compression unit is input to the compression unit 301, the bit stream can be continuously output without interruption. Is shown. On the decompressor side, the decompression process can be started after the elapse of zT time after receiving the head of the compression unit.

FIG. 20 is a diagram showing the input / output timing of each block of the third embodiment derived from FIG. 19, where 811 is an input image signal of the compression means 301 (FIG. 15), and 812 is a smoothing signal. It is an output bit stream of the means 401 (FIG. 15), and the notation in the figure is equivalent to the example of FIG.

In the third embodiment, in the third embodiment, the delay from the start of the input of the image signal 811 in the compression unit 301 to the start of the output of the bit stream 812 from the smoothing unit 401 is expressed by the above equation. 2, which is a delay time shorter than the compression unit time T.

On the other hand, FIG. 21 is a diagram showing the input / output timing of each block of the third conventional example derived from FIG. 19, and the notation in the figure is the same as that in the examples of FIGS. .

In this figure, in the third conventional example, the bit stream 812 is started to be output from the smoothing means 401 (FIG. 17) after the input of the image signal 811 by the compression means 301 (FIG. 17) is started. Is a delay time longer than the compression unit time T.

FIG. 22 is a block diagram showing a fourth embodiment of a signal processing apparatus having a moving picture information decompression function according to the present invention, wherein 431 is a code storage means, 432 is an address generation means, and 433 is a decompression startable. Time information restoring means 43
Reference numeral 4 denotes a selection means, and 509, an input terminal for decompression startable time information. Portions corresponding to those in FIG. 7 are denoted by the same reference numerals, and redundant description is omitted.

In the fourth embodiment, the decompression process is started with a smaller delay time than before, based on the information on the possible compression unit decompression start time input from the outside or included in the bit stream. This is what made it possible.

In FIG. 22, a moving image compression code signal transferred at a predetermined transfer rate is input from an input terminal 502 and stored in a code storage means 431 in a data transfer rate conversion means 402. This signal is output from the decompression means 3 after a lapse of a predetermined time from the start of the compression unit.
In step 02, the image data is decompressed by a decompression procedure specified in the MPEG2 system, is formed into an interlaced image by the interlaced image forming means 202, and is output from the output terminal 102.

The timing at which the head data of the compression unit is read from the code storage means 431 is determined based on the decompression start possible time information included in the bit stream. This information is compression unit decompression start possible time information generated by the signal processing device of the third embodiment described with reference to FIGS. 15 to 19, and corresponds to zT in Expression 3 above.

If this information is included in the user data in the bit stream, it is restored by the compression unit decompression startable time information restoring means 433, and when it is input from outside, it is input from the input terminal 509. Use what is entered. Selection means 434 selects appropriate information from both.
And supplies it to the address generation means 432. The address generating means 432 sends the head data of the compression unit to the decompression means 302 when zT time has elapsed since the input of the head data of the compression unit.
In 02, an address is generated so that only the required data is sent. Since this zT time can be shorter than T, the result obtained by expanding the image compression unit before the last information of the information obtained by compressing the image compression unit is input to the transfer rate conversion unit 402. The head of the image information to be output can be output from the decompression means 302.

FIG. 23 is a block diagram showing a fourth conventional example of a signal processing device having a moving picture information decompression function according to the fourth embodiment. Reference numeral 402 'denotes data transfer rate conversion means. Are assigned the same reference numerals.

In the fourth embodiment, the transfer rate converting means 402 determines the decompression start time based on the compression unit decompression startable time information with respect to the fourth conventional example. This is a signal processing device with added functions.

As shown in FIG. 23, the fourth conventional example does not have a function of calculating the compression unit expansion start time from the compression unit expansion start possible time information. The information is transferred to the transfer rate converter 40.
Decompression processing must be started at the time of input to 2 ',
The head of the image information obtained as a result of expanding the image compression unit cannot be output to the expansion means 302 '. That is, in the fourth embodiment, the compressed data can be expanded with a lower delay than in the fourth conventional example.

FIG. 24 is a diagram showing the input / output timing in each block of the fourth embodiment. Reference numeral 871 denotes input compression information of the data transfer rate conversion means 402 (FIG. 22), and reference numeral 872 denotes output. The notation in the figure is equivalent to the example in FIG.

In the figure, in the fourth embodiment,
After the input of the compression information 871 to the data transfer rate conversion means 402 is started, the data transfer rate conversion means 4
02 to the start of output of the compression information 872 is the time zT in the above equation 3, and the compression unit time T
It is possible to have a shorter delay time. As is clear from FIG. 19, even in this delay time, the code amount in the compression unit is controlled so that data can be expanded without data shortage during expansion.

On the other hand, FIG. 25 is a diagram showing the input / output timing in each block of the fourth conventional example, and the notation in the figure is the same as that in the examples of FIGS.

In this fourth conventional example, after the input of the compression information 871 to the data transfer rate conversion means 402 '(FIG. 23) is started, the compression information 872 is transmitted from the data transfer rate conversion means 402'. The delay before output starts is the compression unit time. The delay time is longer than T.

FIG. 26 is a block diagram of a fifth embodiment of a signal processing apparatus having a moving picture information compression function according to the present invention. Omitted. FIG. 27 is a block diagram showing a specific example of the compression means 301 in FIG.
311 is a main compression unit, 321 is a temporal reference (temporal reference) counting unit, and 322 is a temporal reference unit.
Reference instructing means 323 is a skip means, and 324 is a code amount counting means.

In the fifth embodiment, when a skip picture defined by the MPEG2 system occurs, the surplus code amount secured by skip can be optimally distributed between pictures.

In the fifth embodiment, the input terminal 101
The image information input from is converted by the compression unit configuration means 201 into the order of macroblocks defined by the MPEG2 system, and the compression means 301 is converted into codes defined by the MPEG2 system,
Further, the data is converted into a data transfer rate according to the specifications of the transmission path by the smoothing means 401 and output from the output terminal 501.

In the MPEG2 system, "temp"
The compression information is generated by adding a frame number called “oral reference”. Therefore, as shown in FIG.
Is set, and the temporal reference counted here is
The main compression means 311 through the al reference indicating means 322
To communicate. In a normal operation, the temporal reference instruction means 322 transmits the value of the temporal reference counting means 321 to the main compression means 311 as it is. Compression means 30
The code amount obtained as a result of the compression by
At 24, when it is determined that a large image determined by the MPEG2 system has occurred, a skip instruction unit 323 determines a picture to be skipped and instructs the main compression unit 311. Also, several frames of te after the large image
temp to set the mporal reference as needed
A predetermined instruction is given to the oral reference instruction means 322.

The method of setting the temporal reference of several frames after the large image in the fifth embodiment will be described later.

FIG. 28 shows a compression means 30 according to a fifth conventional example having a moving picture information compression function for the fifth embodiment.
FIG. 28 is a block diagram showing the configuration of 1 ', where the same reference numerals are given to portions corresponding to FIG.

In this figure, in the fifth conventional example, the code amount obtained as a result of compression by the compression means 301 'is counted by the code amount counting means 324, and it is determined that a large image defined by the MPEG2 system has occurred. In this case, the skip instructing unit 323 determines to skip the required number of fields following the large image, and instructs the main compressing unit 311.

In the fifth prior art example, even after a large image, a temporal reference is established as defined by the MPEG2 system.
The value of the temporal reference counting means 321 is used as it is.

FIG. 29 is a diagram showing an example of input / output and processing timing of each block of the fifth embodiment shown in FIGS. 26 and 27. FIG. 30 is a diagram showing each block of the fifth conventional example. FIG. 3 is a diagram showing an example of input / output and processing timing of the present invention. In these drawings, the number following "Frm" represents the frame number, the number following Fld represents the field number, and the number following "Ref" is the tempo defined by the MPEG2 system.
Represents ral reference. Note that the temporal reference increases in frame units. Reference numeral 821 denotes the timing of the macroblock signal sent from the compression unit forming unit 201 to the compression units 301 and 301 'in units of fields. Reference numeral 822 denotes a compression process performed by the compression units 301 and 301' and the The timing at which the bit stream is sent is represented on a field basis, 823 represents the timing at which the bit stream is output from the smoothing means 401 on a field basis, and 824 represents the surplus transfer period caused by picture skipping.

Here, the combined use with the third embodiment described above is not performed, and the output 823 of the smoothing means 401 is
An example in which only the bit stream of the field for which the output 822 of the compression means 301, 301 'is completed is output will be described. The field Fld1 in the frame Frm1 is a large image, and this field occupies a longer time in the output 823 of the smoothing means 401 than other fields.

FIG. 31 is a diagram schematically showing a time interval and a scanning line position shift between the reference image at the time of compression and the reproduction at the time of the operation shown in FIG. 29 of the fifth embodiment, and FIG. FIG. 31 is a diagram schematically showing a time interval and a scanning line position shift between the reference image at the time of compression and the reproduction at the time of the operation shown in FIG. 30 of the conventional example, in which each circle represents a field; The horizontal axis represents the time interval between the fields, and the vertical axis represents the scanning line position shift between the fields.
“Ref”, “Frm”, and “Fld” are shown in FIG. 29 and FIG.
Corresponding to the same code of 0, "Skip" indicates a field not subjected to compression processing, "repeat" indicates a reproduction position of a field missing by Skip, and an arrow in the figure indicates a forward prediction in the MPEG2 system. It represents a reference relationship for The repeat field is defined to repeatedly output the previous reproduced image on the same field side.

In the operation of the fifth conventional example shown in FIG.
The image immediately after the large image (field Fld1 in frame Frm1) is divided into two fields (field Fld in frame Frm1).
2 and the field Fld1 in the frame Frm2) skipped and the subsequent image (the field Fld in the frame Frm2)
The compression process is restarted from 2). In the MPEG2 system, skipping is performed in units of two fields, except in special cases.

The field Fld1 in the frame Frm1 is the first half field in this frame, and
This is an I picture defined by the EG2 system, and is a frame Frm2
If the middle field Fld2 is a P-picture defined by the MPEG2 system in the latter half of this frame, it is specified that the field Fld2 in the frame Frm2 refers only to the field Fld1 in the frame Frm1.

According to this, the field Fld2 in the frame Frm2 is temporally distant from the field Fld1 in the frame Frm1 and has a different scanning line position, so that the difference from the reference image is often large. for that reason,
Compression efficiency is reduced, and image quality may be degraded with the same code amount distribution.

However, when the compression processing of the field Fld2 in the frame Frm2 ends, the surplus transfer section due to skipping ends, so that the surplus transfer section cannot be allocated to the field Fld2 in the frame Frm2. Therefore, field F in frame Frm2
The image quality of ld2 is degraded, and the image quality of the subsequent image that refers to this is also degraded.

On the other hand, in the operation of the fifth embodiment shown in FIG. 29, in the large image (field Fld in frame Frm1)
1) Immediately after one field (field Fld2 in frame Frm1), compression is performed without skipping,
The field (the field Fld1 in the frame Frm2, the field Fld2 in the frame Frm2) is skipped, and the compression processing is restarted from the subsequent image (the field Fld1 in the frame Frm3). However, in the MPEG2 system, temp
In order to indicate the existence of a large image by discontinuity of the oral reference, temp for the field Fld2 in the frame Frm1
The oral reference is 2.

The field Fld1 in the frame Frm1 is the first half field of the frame, which is an I picture defined by the MPEG2 system, and the field Fld1 in the frame Frm1 is
If ld2 is the latter half field in this frame and is a P picture defined by the MPEG2 system, the field Fld2 in the frame Frm1 is replaced by the field Fld in the frame Frm1.
It is stipulated that only one is referred to. In the fifth embodiment, the field Fld2 in the frame Frm1 transmitted after the skip is the field Fld2 in the frame Frm1.
Since the temporal distance is not far from ld1, the reference error is smaller than in the case of the fifth conventional example, and the compression efficiency is improved.

The field Fld in the frame Frm1
Since there is a time margin between the end of the compression processing of No. 2 and the start of the bit stream output, the surplus period caused by the skip is assigned not only to the field Fld1 in the frame Frm1 but also to the field Fld2 in the frame Frm1. It is possible to obtain a reproduced image with little deterioration in image quality by optimizing the code amount distribution between the two.

The field Fld1 and the frame Frm3 in the frame Frm3 in the fifth embodiment shown in FIG.
The middle field Fld2 has a longer time distance from the reference image than the fifth conventional example shown in FIG. 32, but since these images can use two images as the reference image,
Field Fld2 in frame Frm2 in the fifth conventional example
Reference can be performed more efficiently.

FIG. 33 shows another example of input / output and processing timing of each block of the fifth embodiment, and FIG.
29 is a diagram showing another example of input / output and processing timing of each block of the fifth conventional example, and the notations in these diagrams are equivalent to those in FIG. 29 and FIG.

FIG. 35 is a diagram schematically showing a time interval and a scanning line position shift from a reference image at the time of compression and reproduction according to the fifth embodiment, and FIG. 36 is a diagram of the fifth conventional example. FIG. 9 is a diagram schematically illustrating a time interval and a scanning line position shift between a reference image at the time of compression and reproduction corresponding to FIG.
The notation in these is equivalent to FIGS. 31 and 32.

In this example, both the field Fld1 in the frame Frm1 and the field Fld2 in the frame Frm2 are large images, resulting in a skip picture. In this example, the field Fld1 in the frame Frm1 and the field Fld2 in the frame Frm2 are compressed as an I picture, and the other images are compressed as P pictures.

In the fifth conventional example, as shown in FIGS. 34 and 36, a skip occurs after each of the field Fld1 in the frame Frm1 and the field Fld2 in the frame Frm2. As a result, the image after skipping (the field Fld1 in the frame Frm4) is a frame Frm2 in which the scanning line position two frames before is different from the field Fld1 in the frame Frm1 which is the image three frames before.
It is necessary to refer to the middle field Fld2, and the compression efficiency is reduced. Moreover, since the surplus transfer section due to skipping ends when the compression processing of the field Fld1 in the frame Frm4 ends, the surplus transfer section cannot be assigned to the field Fld1 in the frame Frm4. Field Fld1
The image quality of the image is deteriorated, and the subsequent pictures that refer to this image also deteriorate in image quality.

On the other hand, in the fifth embodiment, as shown in FIGS. 33 and 35, two fields immediately after the field Fld1 in the frame Frm1 are skipped, but the field Fld1 in the frame Frm2 is skipped. For the field Fld2, compression is performed without skipping the immediately succeeding field (field Fld1 in Frm3),
The fields (field Fld2 in frame Frm3 and field Fld1 in frame Frm4) are skipped, and the compression process is restarted from the subsequent image (field Fld2 in frame Frm4). However, in the MPEG2 system, temp
In order to indicate the presence of a large image by discontinuity of the oral reference, temp for the field Fld1 in the frame Frm3
The oral reference is 4.

By adopting such a configuration, the reference three frames before, which occurs in the conventional example, does not occur, and the reference efficiency is improved.

The embodiments of the present invention have been described above, but these embodiments are not mutually exclusive,
It is also possible to configure a signal processing device with less delay and image quality degradation by combining the respective components.

[0131]

As described above, according to the present invention,
The compression unit is limited to the field image only, the delay time associated with the frame configuration is eliminated, and before the last information of the field image information, which is the compression unit, is input to the compression unit configuration means, the image compression unit consisting of this field is Since the head part can be output from the compression unit structuring means, it is possible to reduce the delay time involved in forming the compression unit.

Further, according to the present invention, even if reading from the smoothing buffer is started before the input of the image in the compression unit is completed, the bit allocation within the compression unit can be output without interruption. Therefore, before the last information of the image information constituting the compression unit is input to the compression means, the head of the data obtained as a result of compressing this image compression unit is smoothed. It is possible to output from the means, and it is possible to reduce the delay of one or more compression units due to the smoothing of the data transfer rate.

Further, according to the present invention, one or more images immediately after the large image are compressed, the subsequent images are skipped, and a time for transmitting the code in which the large image has occurred is prepared. The image compressed immediately after the large image set as described above is an image that is temporally close to the reference image, so that the image quality is less deteriorated than in the conventional example. In addition, since the code of this image has a time margin from the input of the image to the output of the bit stream, it is possible to allocate an additional code to the image due to skipping. It is possible to reduce the deterioration of the image quality of the image compressed immediately after.

Further, according to the present invention, a flag indicating that all the predetermined sets of compression units have a field structure is output in the bit stream or as an external output. Can perform interlace conversion without delay, so that the delay caused by converting the frame structure into an interlace image at the time of decompression can be reduced. Even when a frame structure is included, the delay due to interlace conversion is reduced in the field structure section, the delay due to interlace conversion is added in the frame structure period, and field repetition or thinning is appropriately performed at the boundary between the two. By doing so, it is possible to reduce the delay in the field structure section.

Furthermore, according to the present invention, the information indicating the decompression start possible time is transmitted from the compression device to the decompression device, and the decompression process is started at the time indicated by this information. Can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of a signal processing device having a moving image information compression function according to the present invention.

FIG. 2 is a block diagram showing a specific example of a compression unit constituting unit in FIG. 1;

FIG. 3 is a timing chart showing an operation in the first conventional example.

FIG. 4 is a timing chart showing an operation of the first embodiment shown in FIG. 1;

FIG. 5 is a block diagram showing a first conventional example of the first embodiment shown in FIG. 1;

FIG. 6 is a block diagram illustrating an example of a compression unit configuration unit in FIG. 5;

FIG. 7 is a block diagram showing a second embodiment of a signal processing device having a moving picture information decompression function according to the present invention.

FIG. 8 is a block diagram showing a specific example of an interlaced image forming unit in FIG. 7;

FIG. 9 is a block diagram showing a second conventional example for the second embodiment shown in FIG. 7;

FIG. 10 is a block diagram illustrating an example of an interlaced image forming unit in FIG. 9;

FIG. 11 is a timing chart showing an operation of the second embodiment shown in FIG. 7;

12 is a timing chart showing an operation of the second conventional example shown in FIG.

FIG. 13 is a timing chart showing another operation of the second embodiment shown in FIG. 7;

FIG. 14 is a timing chart showing still another operation of the second embodiment shown in FIG. 7;

FIG. 15 is a block diagram showing a third embodiment of the signal processing device having the moving image information compression function according to the present invention.

FIG. 16 is a block diagram showing a specific example of a control unit in FIG.

FIG. 17 shows a third embodiment corresponding to the third embodiment shown in FIG. 15;
FIG. 6 is a block diagram showing a conventional example of FIG.

18 is a block diagram illustrating an example of a control unit in FIG.

FIG. 19 is a diagram showing a code amount transition by control in the third embodiment shown in FIG. 15 and the third conventional example shown in FIG. 17;

FIG. 20 is a timing chart showing an operation of the third embodiment shown in FIG.

FIG. 21 is a timing chart showing an operation of the third conventional example shown in FIG. 17;

FIG. 22 is a block diagram showing a fourth embodiment of the signal processing device having the moving picture information decompression function according to the present invention.

FIG. 23 is a block diagram showing a fourth conventional example corresponding to the fourth embodiment shown in FIG.

FIG. 24 is a timing chart showing an operation of the fourth embodiment shown in FIG. 22;

FIG. 25 is a timing chart showing an operation of the fourth conventional example shown in FIG. 23;

FIG. 26 is a block diagram of a fifth embodiment of a signal processing device having a moving image information compression function according to the present invention.

FIG. 27 is a block diagram showing a specific example of a compression unit in FIG. 26;

FIG. 28 is a block diagram showing a fifth conventional compression means corresponding to the fifth embodiment shown in FIG. 27;

FIG. 29 is a timing chart showing an operation of the fifth embodiment shown in FIG. 26;

FIG. 30 is a timing chart showing an operation of the fifth conventional example shown in FIG. 28;

FIG. 31 is a diagram showing a picture reference relationship according to the fifth embodiment shown in FIG. 26;

FIG. 32 is a diagram showing a picture reference relationship in the fifth conventional example shown in FIG. 28;

FIG. 33 is a timing chart showing another operation of the fifth embodiment shown in FIG. 26;

FIG. 34 is a timing chart showing another operation of the fifth conventional example shown in FIG. 28;

FIG. 35 is a diagram illustrating another picture reference relationship according to the fifth embodiment illustrated in FIG. 26;

FIG. 36 is a diagram showing another picture reference relationship of the fifth conventional example shown in FIG. 28;

FIG. 37 is a diagram illustrating a pixel transfer order of an interlaced image.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Input terminal of moving image signal 102 Output terminal of image signal 201 Compression unit forming means 202 Interlace image forming means 301 Compressing means 302 Decompressing means 401 Smoothing means 402 Data transfer rate converting means 501 Output terminal of compressed signal 502 Input of compressed signal Terminal 506 Output terminal of field structure flag 507 Input terminal of field structure flag 508 Output terminal of decompression startable time information 509 Input terminal of decompression startable time information 601 Control means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masaru Takahashi 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Pref. Multimedia System Development Division, Hitachi, Ltd.

Claims (9)

[Claims] 1. A signal processing apparatus having a compression unit constituting means for composing a moving image signal into information for each frame or field which is a unit for image compression, and image information constituting a field which is a unit for image compression. A signal processing device for outputting the head of the image compression unit consisting of the field from the compression unit configuration unit before the last information of the compression unit configuration unit is input to the compression unit configuration unit. 2. A signal processing apparatus comprising a compression unit constituting means for composing a moving picture signal into information for each frame or field as an image compression unit, and a compression means, wherein a predetermined set of compression units has a field structure. A signal processing device which includes information indicating presence in compressed information or outputs the information to the outside. 3. A signal processing apparatus comprising: compression means for compressing a moving image signal for each frame or field as an image compression unit; and smoothing means for smoothing a data transfer rate of the compressed signal. Before the last information of the image information constituting the frame or field as a unit is input to the compression means, it is necessary to output from the smoothing means the head of the data obtained as a result of compressing the image compression unit. Characteristic signal processing device. 4. The method according to claim 3, wherein the amount of data obtained as a result of the compression from the start of output of the head of the data to the completion of compression of the last information of the image information is reduced by the smoothing. A signal processing device which controls according to an amount of data output from a smoothing unit or a remaining buffer amount of the smoothing unit. 5. A signal processing apparatus having a compression means for compressing a moving image signal for each frame or field as an image compression unit, wherein information relating to a decompression start start time is included in the compressed information or is externally provided. A signal processing device for outputting. 6. A signal processing apparatus having a compression means for compressing a moving image signal for each frame or field as an image compression unit, wherein a large image whose data amount obtained as a result of compression exceeds a predetermined value exists. A signal processing apparatus, wherein one or more image compression units are thinned out as necessary from one or more image compression units subsequent to the next image of the large image in the input order and compressed. 7. The information processing apparatus according to claim 6, wherein information indicating a temporal arrangement of information obtained by compressing an image subsequent to the large image is discontinuous with information indicating a temporal arrangement of the large image. A signal processing device for creating compression information. 8. A signal processing apparatus comprising: decompression means for decompressing moving image information compressed for each frame or field as a compression unit; and interlaced image forming means for generating an interlaced image from the decompressed information. Before the last information of the information obtained by expanding the image compression unit having the structure is input to the interlace image forming means, the head of the interlaced image information obtained as a result of expanding the compression unit is output from the interlace image forming means. A signal processing device comprising: 9. A signal processing apparatus comprising: a transfer rate conversion means for converting a transfer rate of moving image information compressed for each frame or field as a compression unit; and a decompression means for expanding an output of the transfer rate conversion means. In the method, before the last information of the information obtained by compressing the image compression unit is input to the transfer rate conversion means, the head of the image information obtained as a result of expanding the image compression unit is output from the expansion means. Characteristic signal processing device.