JPH0965200A - Signal processing apparatus and method thereof - Google Patents

Abstract

(57) Abstract: In a signal processing device for performing compression processing on image signal data, an image quality is improved by performing efficient image compression more suitable for an actual shooting situation. SOLUTION: A control signal, an information signal, etc. in a camera shake correction circuit 4 and an AE / AWB section 5 of a camera block 1 are
A signal path is formed so that it can be supplied to the motion detection 12 and the division coefficient setting unit 13 on the side of the compressed signal processing block 6, and these signals are used as discriminative elements for motion detection and division coefficient setting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing device for performing compression processing on image signal data, and more particularly to a signal processing device suitable for mounting on a video camera device or the like.

[0002]

2. Description of the Related Art In recent years, as a video camera device, there has been considered a digital video camera device which converts a picked-up image signal into a digital signal and records it on a recording medium such as a magnetic tape. In such a video camera device, generally, when a color video signal is directly converted to a digital signal and recording / reproducing is performed, the amount of data to be handled becomes enormous, so that it is converted into a digital signal. It has been considered to encode image data and audio data to compress the transmission data amount.

FIG. 8 is a block diagram showing a configuration example of a video camera device having a compression signal processing system for compressing image data as described above. The camera block 1 in this figure is provided with a camera 2 using, for example, a CCD element as an image pickup element. The image pickup signal taken by the camera 2 is supplied to the camera signal processing circuit 3. The camera signal processing circuit 3 performs required signal processing on the input image pickup signal and outputs the image pickup signal to the compressed signal processing block 6 as an image signal by a digital signal, for example. In this case, as shown in FIG. 8, the Y signal (luminance signal), the color difference signal Cr (RY) signal, and the component signal of the Cb (BY) signal are output as image signal data.

Further, in the camera block 1 in this case, a camera shake correction circuit 4 is provided so as to cancel the image shake caused by the camera shake of the photographer. In addition, AE (Automatic Exposure) / AWB (Auto
A matic white balance) section 5 is provided to automatically adjust the white balance appropriately according to the state of the image pickup signal supplied to the camera signal processing circuit 2, and variably control the aperture of the lens of the camera 2 and the shutter speed. Then, the exposure is controlled so that an appropriate exposure can be obtained.

Y and C output from the camera block 1 side
The image data signals of r and Cb are supplied to the blocking circuit 7 in the compressed signal processing block 6. In the blocking circuit 7, for example, an image signal supplied from the camera block 1 side is converted into (8 × 8) DCT block structure data. The (8 × 8) DCT block data output from the blocking circuit 7 is D
It is supplied to the CT circuit 8 and the motion detector 12. And
The DCT circuit 8 performs DCT (Discrete Cosine Transform) processing, which is a kind of orthogonal transformation, on the input data and outputs it as DCT coefficient data. The DCT circuit 8 has, for example, two types of operation modes, that is, an intra-frame DCT and an intra-field DCT. When the motion detection unit 12 detects a still image, the intra-frame DCT process is executed to detect the motion. If so, the in-field DCT processing is executed. It should be noted that the motion detection in the motion detection unit 12 in this case is determined based on a signal input from the blocking circuit 7 or the like in the compressed signal processing block 6, for example. Is omitted here. The scan unit 9 scans the data in a predetermined pattern, for example, zigzag scan, so as to obtain the data of the block pixel in the order from the low-frequency term to the high-frequency term for the data subjected to the DCT processing by the DCT circuit 8, and quantizes the data. Supply to the circuit 10.

The quantizing circuit 10 divides the AC data of the coefficient data supplied from the scanning section 9 based on the quantization step (corresponding to the division coefficient) set by the division coefficient setting section 13. , The remainder is rounded by a predetermined method and the quotient is converted into an integer. In this quantization, the division is performed by a quantization step having a large width as the coefficient data of the alternating current becomes a high frequency band. Although detailed description is omitted here, in the division coefficient setting unit 13, the quantization number determined by the data amount of the encoding circuit 11 described later, the quantization circuit 1
The division coefficient is determined based on the maximum absolute value of the coefficient data of the AC component quantized by 0, the distribution position of the coefficient data in the DCT block, and the like.

The output of the quantizing circuit 10 is the encoding circuit 1.
1 is supplied. The coding circuit 11 performs, for example, run length coding, Huffman coding, etc. as variable length coding. In this way, the image data processed by the compression processing signal block 6 compresses the image data captured by the camera block 1.

Then, the compressed image data output from the compression processing signal block 6 is supplied to the recording processing block 14 and processed so as to have a data structure and a recording form suitable for the recording medium 15. For example, if the recording medium 15 is a magnetic tape and recording is performed by a rotary head, the recording processing block 14 performs error correction encoding, data framing, etc., and then performs recording from the channel encoding circuit. A recording signal is supplied to the rotary head via an amplifier, and magnetic recording is performed on the magnetic tape.

Further, the reproduction processing block 16 reads the data recorded on the recording medium 15, performs a required decoding process on the read data, and finally outputs it as a video signal.

[0010]

By the way, in the compressed signal processing block 6 as described above, the motion detecting unit 12 determines whether the motion is still or motion in accordance with the conditions such as the motion of the image or the pattern of the image. In the division coefficient setting unit 13, the quantization step in the quantization circuit 10 is made variable so that compression suitable for the image state is performed. For example, in terms of reproduced image quality after decoding, For example, it is preferable that the accuracy of motion detection in the motion detection unit 12 be improved. For example, various methods of motion detection have been considered, from a method of detecting by a simple correlation between fields to a detection method using a relatively advanced prediction technique, but a compressed signal as shown in FIG. 8 is used. Considering a case where a video camera device including the processing block 6 is provided for consumer use, it is possible to reduce the cost by using a simple structure for the motion detection unit 12. Naturally conceivable. However, such simple motion detection also lowers the detection accuracy, which also affects the image quality.

The quantization step (division coefficient) is
Based on a table preset in the division coefficient setting unit 13, if a “class number” is given by classifying the absolute value of the AC component of the DCT block data, the rest of the predetermined area division of the DCT block data Although it is uniquely determined by the assigned area number and the quantization number, for example, if the quantization step can be variably set more flexibly according to the state of the actual captured image, the image data It is preferable because the efficiency of compression is improved and a higher quality image can be obtained.

[0012]

Therefore, in order to solve the above-mentioned problems, the present invention performs necessary processing on input image signal data to perform data compression, and at the same time, an image pickup device and this image pickup device. A signal processing device is input so as to input information for required operation control or signal processing control in an imaging unit including an image processing unit that performs required processing on a captured image and use the information for operation control of a predetermined functional circuit unit. I decided to configure it. In addition, as a signal processing method, an image pickup unit including an image pickup apparatus and an image processing section that performs a necessary process on a picked-up image of the image pickup apparatus while performing necessary processing on input image signal data The information for the required operation control or signal processing control in (3) is input and used for the operation control of a predetermined function.

According to the above arrangement, not only the information obtained in the compressed signal processing circuit system but also the camera including the video camera and the image pickup signal processing unit thereof is used as a judgment element for the motion detection or the coefficient setting of the quantization. Including AE (Automatic Exposure) and AWB (AutomaticW) including detection information and control signals for camera shake correction in the signal processing system
It is possible to use control signals and information signals related to hite balance).

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a signal processing device of the present invention will be described below. In this case, description will be made assuming that the signal processing device of the present embodiment is mounted on the video camera device. FIG. 1 is a block diagram schematically showing a main part of a video camera device provided with the signal processing device according to the present embodiment. In the camera block 1 of this figure, as an image pickup device, for example, a lens block and a CCD
A camera 2 including an image pickup device such as a device is provided. For example, the image pickup signal input from the camera 2 is supplied to the camera signal processing circuit 3 where the required processing is performed. In this case, finally, the Y signal (luminance signal), the Cr (RY) signal, and the C
The image signal is output to the compressed signal processing block 6 as an image signal of a component signal including the color difference signal of b (BY).

Further, in this case, the camera block 1 is provided with the camera shake correction circuit 4 so that the camera shake of the image due to the camera shake of the photographer can be canceled. As a method for camera shake correction by the camera shake correction circuit 4, first, an image shake detection unit that detects information about image shake in the camera shake correction circuit 4 is provided. As such an image shake detection unit, for example, a configuration for detecting horizontal / vertical vibration of the video camera apparatus main body by an angular velocity sensor or the like, or a motion vector of an image from an image signal sequentially input from the camera signal processing circuit 3 is detected. It is conceivable that the detection is performed. Then, the camera shake correction circuit 4 sets the amount of movement in the horizontal / vertical direction for image shake correction based on the detection information of the image shake detector. Then, based on this horizontal / vertical movement amount data, the camera 2
By performing the variable control of the read position of the CCD element and the variable control of the write position of the image memory provided in the camera signal processing circuit 3, the image shake due to the hand shake is canceled. Alternatively,
A method of driving the variable apex prism provided in the camera 2 based on the data of the amount of movement in the horizontal / vertical directions to cancel the image shake may be adopted.

In the camera block 1, the AE
(Automatic Exposure) / AWB (Automatic White Ba
lance) section 5 is provided. This AE / AWB part 5
Automatically adjusts the white balance appropriately according to the state of the image pickup signal of the subject supplied to the camera signal processing circuit 3 and variably controls the lens aperture of the camera 2 and the shutter speed to obtain an appropriate exposure. The control is performed so as to be controlled. For example, in the case of the present embodiment, a sport mode in which an exposure condition suitable for shooting a very fast moving subject is set, or a close-up shooting of a relatively small moving subject is performed. Various shooting modes such as a portrait mode in which a suitable exposure condition is set are provided, and by switching such a mode, an image suitable for an actual shooting situation can be obtained.

In the present embodiment, the AE / AW
The B section 5 is also configured so as to be able to cancel flicker appearing in an image in a room or the like taken by lighting such as a fluorescent lamp in an area where the power supply frequency is 50 Hz, for example, the camera signal processing circuit 3 The interfering modulation component due to flicker is extracted from the video signal and the inverse modulation is performed based on this to remove the flicker from the video signal. Further, in the present embodiment, various information signals and control signals related to the operations of the camera shake correction circuit 4 and the AE / AWB unit 5 are transmitted to the motion detection unit 12 and the division coefficient setting unit 13 of the compressed signal processing block 6 described later. To the line L
It is supplied via ₁ and L ₂ and is used as discrimination information for motion detection and a judgment element for setting a division coefficient at the time of quantization, which will be described later.

Y, C output from the camera block 1 side
The image data signals of r and Cb are supplied to the compressed signal processing block 6 side and first supplied to the blocking circuit 7 in the compressed signal processing block 6. Blocking circuit 7
In, the image data in the interlace scanning order input from the camera block 1 side is converted into the data of the structure of the DCT block of (8 × 8). That is, two (4 × 8) blocks at the same spatial position in the first and second fields that are temporally continuous are combined to form an (8 × 8) DCT block. In the (8 × 8) block thus obtained, the pixel data on the odd-numbered lines are included in the first field, and the pixel data on the even-numbered lines are included in the second field. .

In addition, in the blocking circuit 7, after performing the above-described blocking, shuffling is performed to make the spatial position different from the original image in units of a plurality of macroblocks in one frame. This makes it possible to improve the data compression efficiency.

By the way, the above-mentioned macroblock is formed by a plurality of (8 × 8) DCT blocks. For example, the data processed by the video camera device of the present embodiment is in a 525/60 system such as NTSC. If the image data is of a format corresponding to the component system (Y: Cr: Cb = 4: 1: 1), as shown in FIG.
A total of 6 blocks, each of which is one Y block and one Cr block and Cb block, constitutes one macro block. If the image data is in a format corresponding to the component system (Y: Cr: Cb = 4: 2: 0) in the 525/60 system, the image data shown in FIG.
As shown in (4), four Y blocks at the same position in one frame, one Cr block and one Cb block, for a total of 6 blocks, form one macro block.

The image data which has been subjected to the above-mentioned processing by the blocking circuit 7 is supplied to the DCT circuit 8. This DCT
The circuit 8 performs DCT conversion on the data input as the (8 × 8) block to generate coefficient data (DC component data and AC component data) of the (8 × 8) block. By the way, in this case, in response to the fact that the captured image is a moving image, the DCT circuit 8 relates to the DCT processing in the intra-frame DCT mode and the intra-field DCT.
Two processing modes of T mode are provided. In other words, generally, in the case of a block without motion, the correlation between fields is high. Therefore, when the intra-frame DCT process is performed, the coefficients are concentrated in the low range, but in the block with motion, the correlation between the even field and the odd field is high. Becomes low, and for example, when the intra-frame DCT processing is performed, a large value appears in the high-frequency coefficient, so that the word length of the data after variable-length coding by the coding circuit described later increases. Therefore, in this case, performing the DCT process within the field improves the compression efficiency.

Therefore, in this case, the motion detection unit 12 detects the motion of the (8 × 8) block to be processed by the DCT circuit 8, and when it is detected as the still block, the DCT circuit 8 is detected. In-frame DCT
And if it is detected that the block is in motion, the intra-field DCT is performed.

As a motion detecting method of the motion detecting section 12,
For example, the difference between the fields of the image data supplied to the compressed signal processing block 6 is used to determine the stillness / motion for each (8 × 8) block, or the (8 × 8) block data is A method of making a determination based on coefficient data in the vertical direction when the Hadamard transform is performed is known. In the present embodiment, any detection method may be adopted according to the conditions of actual use, etc., but a detection circuit having a relatively simple configuration may be used. And
In the present embodiment, in addition to such a basic method, various control signals used when the camera shake correction circuit 4 and the AE / AWB section 5 in the camera block 1 perform various operations as described above are transmitted through the lines L ₁ and L. It is configured such that it can be input to the motion detection unit 12 via ₂ and used as a discriminant element for motion detection, which will be described later.

As described above, the DCT circuit 8
The coefficient data of the (8 × 8) block obtained by the conversion processing is supplied to the scanning unit 9. The scanning unit 9 scans and outputs the AC components of the coefficient data in the order of low to high frequencies.

For example, as shown in FIG. 3, so-called zigzag scanning is performed on the coefficient data of the (8 × 8) block subjected to the intra-frame DCT processing in the DCT circuit 8 to reduce the AC component of the coefficient data. The coefficient data is transmitted in order from the frequency term to the high frequency term. DCT
When performing the DCT processing in the field in the circuit 8,
DCT processing is performed for every two (4 × 8) blocks in the same position in the first and second fields. In this case, as shown in FIG. 4, it corresponds to the first field (4
(4 ×) corresponding to the block of (× 8) and the second field
It is assumed that the block of 8) is arranged vertically and is combined and is treated as an array of (8 × 8) blocks. In this case, the DC data DC1 is included in the coefficient data of the first field, and the DC component DC2 is included in the coefficient data of the second field. However, when the coefficient data of each field is treated individually, It is necessary to separate the processing of (1), and the circuit scale increases. Therefore, in the case of the present embodiment, as shown in FIG. 4, instead of the DC component DC2 of the second field, the differential DC component ΔDC2 (= DC
1-DC2). It should be noted that it is obtained by the DCT processing in the field in this way (8 × 8)
Although detailed description is omitted when the coefficient data of the block array of FIG.
By performing a scan of a predetermined pattern different from the zigzag scan described above, the AC component coefficient data is output in order from the low frequency term to the high frequency term.

The coefficient data of the DCT block scanned by the scanning unit 9 as described above is quantized by the quantization circuit 10.
Is supplied to. In the quantization circuit 10, the AC component of the coefficient data is divided based on the set of quantization steps (division coefficients) set by the division coefficient setting unit 13. Here, an outline of coefficient setting for the quantization circuit 10 by the division coefficient setting unit 13 will be described with reference to FIG.

FIG. 5A shows an example of a classification table for setting the quantization step (division coefficient). For example, in FIG. 5A, the maximum absolute values of coefficient data are 0 to 11, 12 to 23, 24 to 35,
It is divided into four ranges of 36 or more, and a class number is assigned to each type of coefficient data of Y, Cr (RY), and Cb (BY) signal components corresponding to this range division. That is, the weighting of quantization is different for each signal component of Y, Cr, and Cb. Referring to this figure, for example, the maximum absolute value of the coefficient data of a certain Y signal component input to the quantization circuit 10 is “20”.
, The class number is assigned “1”,
If the maximum absolute value of the coefficient data of the Cr signal component is "30", the class number "3" will be assigned.

Further, FIGS. 5B and 5C show an example of area number allocation to coefficient data of AC in the block form of (8 × 8), and the intra-frame DCT
In this case, area numbers 0, 1, 2, and 3 are assigned in accordance with the low-range term and the high-range term as shown in FIG. In the case of the intra-field DCT, the areas are divided into upper and lower (4 × 8) blocks as shown in FIG.
Is assigned. This area number setting is fixed based on the format.

The quantization step for certain coefficient data is determined based on the quantization number in addition to the class number and area number described above. Quantization number is 0 to 15
It is assumed that each of the area numbers represents a set of quantization steps, and
The set of quantization steps set for the quantization numbers 0 to 15 are set to different weights depending on the class number. It should be noted that this quantization number corresponds to the encoding circuit 1 described later.
Based on the amount of data in a predetermined unit that is encoded by 0,
It is defined by the format so that it is uniquely determined.

FIG. 5D shows a chart for setting the quantization step based on the class number, the area number and the quantization number. As a way of referring to this figure, for example, if the maximum absolute value of the coefficient data of a certain Y signal component input to the quantization circuit 10 is “20”,
As shown in FIG. 5A, "1" is assigned as the class number. The quantization number at this time is the encoding circuit 1
It is assumed that “10” is determined based on the amount of data to be encoded by 0. Then, in FIG. 5D, the row of the quantization number 10 in the column of the class number 1 shown by the hatched portion A (hatched portion B) is referred to, and therefore the hatched portion is based on this quantization number. The quantization step (1
・ The set of 1 ・ 2 ・ 2) will be selected. And
Assuming that the coefficient data of the Y signal component is the data located in the portion corresponding to the area number “2” described in FIG. 5B, for example, the set of quantization steps (1.1.2.2) Of these, "2" (indicated by the halftone dot area E) is selected as the quantization step corresponding to the area number "2" indicated by the shaded area D.

The division coefficient setting unit 13 determines the quantization step, that is, the division coefficient by referring to the tables shown in FIGS. 5A, 5B and 5C as described above. Then, in the quantization circuit 10, division is performed on the coefficient data of the AC component based on the quantized coefficient determined by the division coefficient setting unit 13. For example, if the coefficient data of the Y signal component described above is used, The quantization circuit 10 will perform division on this data by the quantization step “2”.

In this way, by setting the quantization step as described with reference to FIG. 5, (8 × 8)
It is understood that, in principle, the AC component coefficient data of the DCT block is quantized so as to become coarser from the low frequency region to the high frequency region, and the coefficient setting is made according to the image pattern (saturation). To be done.

In the division coefficient setting unit 13 of the present embodiment, the control signals and information signals from the camera shake correction circuit 4, the AE / AWB unit 5, etc. supplied from the camera block 1 are supplied to the lines L ₁ and L _2. It is possible to supply via. Then, these signals are used as a judgment element for determining the division coefficient, which will be described later.

The output of the quantizing circuit 10 shown in FIG. 1 is supplied to the encoding circuit 11. As the variable length coding, the coding circuit 11 performs, for example, run length coding, Huffman coding, etc. on the input data and outputs the data.
As described above, the compression processing signal block 6
In, the image data captured by the camera block 1 is compressed.

The compressed image data output from the compression processing signal block 6 is supplied to the recording processing block 14,
Processing is performed so that the data structure and the recording form are suitable for the recording medium 15. In the present embodiment, for example, the recording medium 15 is a magnetic tape and recording is performed by the rotary head. In the recording processing block 14, error correction coding, data framing, etc. are performed.
A recording signal is supplied from a channel encoding circuit to a rotary head via a recording amplifier to perform magnetic recording on a magnetic tape.

The reproduction processing block 16 reads the data recorded on the recording medium 15, performs a decoding process on the read data, and finally outputs it as a video signal, but a detailed description thereof is omitted here.

For example, conventionally, the decision element for the motion detection of the motion detection section 12 in the compressed signal processing block 6 and the decision element for the division coefficient setting of the division coefficient setting section 13 are in the compression signal processing block 6. However, in the present embodiment, the control signal and the information signal in the camera shake correction circuit 4 and the AE / AWB section 5 of the camera block 1 are also used in the motion detection section 12 and the division. The coefficient setting unit 13 is configured to be used as a determination element. Therefore, in the present embodiment, as described above, the camera shake correction circuit 4 operates in the line L ₁
Is connected to the motion detection unit 12 and the division coefficient setting unit 13, and the AE / AWB unit 5 is connected to the motion detection unit 12 and the division coefficient setting unit 13 by a line L ₂ . This makes it possible to improve the accuracy of motion detection and set the division coefficient according to the condition of the image that changes due to the situation of the actual shooting site, and as a result, the video camera device of the present embodiment can be set. Efficient compression processing, which is more suitable for the state of the image to be captured, is performed, and a better reproduced image quality after decoding can be obtained.

FIG. 6 is a block diagram showing the DCT circuit 8 and the motion detection circuit 12 shown in FIG.
As shown in this figure, the CDT circuit 8 performs a DCT process in the horizontal direction on the data of the (8 × 8) block supplied from the blocking circuit 7 in the first stage block 20.
A RAM 24 for accumulating the data output from the first-stage block 20 and a second-stage block 25 for subjecting the data output from the RAM 24 to vertical DCT processing. Also, the first stage block 20
Is a horizontal DCT circuit 22 that executes DCT processing in the horizontal direction.
In addition, a pre-signal processing unit 21 and a post-signal processing unit 23 that perform required processing in the preceding and subsequent stages are provided. The second-stage processing block 25 is provided with a vertical DCT circuit 27 that executes a DCT process in the vertical direction, a pre-signal processing unit 26 that performs required processing in the preceding and subsequent stages, and a post-signal processing unit 28. Then, in the present embodiment, the output data from the blocking circuit 7, the camera shake correction circuit 4, and the AE / AWB unit 5 are input to the motion detection unit 12.
The signal from is input as a determination element for motion detection.

For example, in the motion detector 12, for each pixel data of the (8 × 8) block input from the blocking circuit 7, P (ij) (i: vertical coordinate, (i = 0 ... 7),
j: horizontal coordinate, (j = 0 ... 7)), and the threshold level is T,

[Equation 1] The calculation is performed as shown in. That is, for each column of (8 × 8) block data, the even rows are added and the odd rows are subtracted. Then, when the sum of the absolute values of the calculation results of each column is equal to or higher than the threshold level T, it is determined to be a motion block, and when it is lower than the threshold level T, it is determined to be a still block. Has been Then, as shown in FIG. 6, either the intra-frame DCT processing or the intra-field DCT processing in the second stage processing block 25 is selected based on the determination result.

For example, in the prior art, the threshold level T has been set to a fixed value by obtaining a value such that an appropriate motion detection result can be obtained on average in response to various shooting situations. On the other hand, in the present embodiment, the threshold level T is variably set based on the control signals from the image stabilization circuit 4 and the AE / AWB section 5, etc. It becomes possible to perform more accurate motion detection. Specifically, for example, when the AE mode is set to the sports mode for shooting a fast-moving subject as the operation of the AE / AWB unit 5, it is estimated that the movement between fields is large. Further, even when the electronic shutter speed of the CCD element of the camera 2 is high, there is a high possibility that the movement between fields will become large. Therefore, when a signal corresponding to such information is input to the motion detection unit 12, if the threshold level T is variably set lower than a certain reference value so that the sensitivity of motion detection is increased,
It becomes possible to obtain the accuracy of motion detection according to the actual shooting situation. Further, if a signal indicating that the electronic shutter speed is very slow is input to the motion detection unit 12, it is highly possible that the subject is stationary. Therefore, the threshold level T is set to a high value to set the stationary state. It is conceivable that the motion detection is performed with a sensitivity suitable for a close captured image. In addition, although a specific example is not given, it is conceivable to use the camera shake detection information or the control information in the camera shake correction circuit 4 for the motion detection.

By performing the motion detection in this manner, for example, even if the cost is suppressed by using a circuit having a simple structure using a relatively simple detection method in the motion detecting unit 12 itself, the motion with high accuracy can be obtained. This makes it possible to perform detection, which is advantageous in, for example, consumer appliances. Further, even when the motion detection unit 12 is configured as a highly accurate one including a microcomputer, a memory, etc., if the information on the camera block 1 side is used for motion detection as in the present embodiment, Further, highly accurate detection can be realized.

Further, also in the division coefficient setting unit 13,
By making it possible to change the quantization number to be selected (the number representing the set of quantization coefficients corresponding to the area number) based on the control signals from the image stabilization circuit 4 and the AE / AWB unit 5, etc., It is possible to make the quantization more suitable for the actual image state.

It is assumed that the selection of the quantization number and the determination of the quantization step based on the selection are basically performed as described above with reference to FIG. 5, based on the format. ) Is not defined in the format regarding the maximum value of the absolute value of the AC component in the quantization division classification table shown in FIG. However, conventionally, only one type of pattern table as shown in, for example, FIG. 5A is used as the pattern for dividing the maximum value of the absolute value of the AC component, and this pattern allows the image data under various shooting conditions to be used. Also, the quantization step was determined so as to fit on average. Therefore, in the present embodiment, as shown in, for example, FIGS. 7A, 7B and 7C, the division coefficient setting unit 13 is provided with a data table for dividing the maximum value of the absolute value of the AC component of the plurality of patterns. To do so. Then, based on the control signals and the like from the camera shake correction circuit 4 and the AE / AWB unit 5, FIG.
The class number is determined by selecting the pattern table of any one of (a), (b) and (c).

For example, when the processing of the camera block 1 is set to the mode for canceling the above-mentioned flicker, it is presumed that the image is taken indoors and under the illumination of a fluorescent lamp or the like. Therefore, if the quantization step is determined by setting the class number based on the range division pattern table of the maximum value of the absolute value of the AC component that matches the captured image under such conditions, the image quality can be significantly improved. You can In addition, as a mode state of the AE / AWB section 5, a table suitable for the above-mentioned sports mode and portrait mode is provided for classifying, and AE / AW
It is also possible to switch the classification table according to the control state of the aperture value by the B unit 5. In particular, when the aperture value changes in response to changes in various shooting modes, etc., the saturation of the background of the captured image changes, so switching the classification table according to this change enables efficient quantum Will be realized.

In the motion detection unit 12 and the division coefficient setting unit 13, which content of the control signal is used as the determination element in the camera shake correction circuit 4 and the AE / AWB unit 5 is not limited to the above. It is not optional and is subject to change according to actual usage conditions. Further, the configuration of each part shown as the above embodiment may be changed within the scope of the gist of the present invention. For example, although the above embodiment has been described as being applicable to the tape-shaped recording medium, it is needless to say that the present invention is applicable to the case where it is applicable to other media such as a disk-shaped recording medium. Further, the above embodiment shows an application example in which the signal processing device of the present invention is mounted on a video camera device. For example, the compressed signal processing block 6 shown in the above embodiment is a single compressed signal processing device. It is also possible to configure as.

[0046]

As described above, the present invention provides a signal processing device for compressing image signal data,
For example, not only the signal obtained in the signal processing device but also the image captured by the imaging device as a video signal may be used as a determination factor for the motion detection for switching the operation mode at the time of orthogonal transformation and the setting of the division coefficient at the time of quantization. As a signal related to operation control on the camera block side that is output as, for example, a control signal and an information signal for camera shake correction, automatic exposure, automatic white balance adjustment, flickerless control, etc., are also used as a determination element, a more actual shooting There is an effect that it is possible to perform highly accurate motion detection according to the situation and the image state and to set an appropriate quantization division coefficient. Therefore, more efficient data compression is performed, and the quality of the captured image is also improved. In particular, even when a motion detection circuit having a relatively simple configuration is adopted from the viewpoint of cost when configuring a consumer digital video camera device or the like,
If the control information on the camera block side is used as the determination element for motion detection as in the present invention, it is possible to realize motion detection with relatively high accuracy.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a video camera device including a signal processing device according to an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a macro block.

FIG. 3 is an explanatory diagram showing an example of a scanning operation of a scanning unit.

FIG. 4 is an explanatory diagram showing an example of in-field DCT processing.

FIG. 5 is an explanatory diagram showing an outline of quantization step determination.

FIG. 6 is a block diagram showing a DCT circuit and a motion detection circuit according to the present embodiment.

FIG. 7 is an explanatory diagram showing an example of a classification table of quantization steps according to the present embodiment.

FIG. 8 is a block diagram showing a configuration of a video camera device as a conventional example.

[Explanation of symbols]

 1 Camera Block 2 Camera 3 Camera Signal Processing Circuit 4 Image Stabilization Circuit 5 AE / AWB Section 6 Compressed Signal Processing Block 7 Blocking Circuit 8 DCT Circuit 9 Scan Section 10 Quantization Circuit 11 Encoding Circuit 12 Motion Detection Section 13 Division Coefficient Setting Section

Claims (6)

[Claims] 1. An image pickup means comprising: an image pickup device; and an image processing means for performing a necessary process on an image picked up by the image pickup device, while performing a required process on the input image signal data to perform data compression. A signal processing device, which is configured to input information for required operation control or signal processing control and use it for operation control of a predetermined functional circuit unit. 2. An orthogonal transform means for performing an orthogonal transform on the input image signal data, and a motion detecting means for switching the operation mode of the orthogonal transform means based on the result of detecting the motion of the input image signal data. And an quantizing means for dividing the output of the orthogonal transforming means to perform data compression, and an imaging means including an imaging device and an image processing means for performing required processing on an image captured by the imaging device. The signal processing device is configured so that the information for required operation control or signal processing control in (1) is input and used as information for motion detection in the motion detecting means. 3. An image pickup device and an image pickup device, which are provided with an orthogonal transform means for performing an orthogonal transform on input image signal data and a quantizing means for dividing an output of the orthogonal transform means to perform data compression. By inputting information for the required operation control or signal processing control in the image pickup means including the image processing means for performing the required processing on the image signal picked up by A signal processing device configured to be used as information. 4. An image pickup device comprising: an image pickup device; and an image processing device for performing a required process on an image picked up by the image pickup device, while performing a required process on the input image signal data to perform data compression. A signal processing method, wherein information for required operation control or signal processing control is input and used for operation control of a predetermined function. 5. The input image signal data is subjected to orthogonal transformation, and at the time of this orthogonal transformation, the arithmetic mode at the time of orthogonal transformation is switched based on the result of motion detection of the input image signal data. , Required operation control in image pickup means including an image pickup device and image processing means for performing required processing on a picked-up image of the image pickup device, while performing quantization by division on the orthogonally transformed data Alternatively, the signal processing method is characterized in that information for signal processing control is input and used as information for the motion detection. 6. The input image signal data is subjected to orthogonal transformation, and the output of the orthogonal transformation is quantized to perform quantization to perform data compression, and at the same time, the image pickup device and a picked-up image of the image pickup device are required. Information for required operation control or signal processing control in the image pickup means including the image processing means for performing processing is input and used as information for setting the division coefficient at the time of quantization. A characteristic signal processing method.