JPS60117886A - Picture processing device - Google Patents

Abstract

PURPOSE:To emphasize or binary-code a minute change in a white level and a minute change in a black level of a video signal by comparing a content of a memory managing means sectioning a storage area of the 1st storage means storing video signal into plural blocks and a content of the 2nd storage means storing a slice level in response to each block. CONSTITUTION:A video signal S1 is stored in prescribed blocks I -IV of a picture memory 12 segmented by the memory managing section 14, the storage content of each block is compared with slice levels L0-L3 corresponding to the blocks at a comparator 17, and a comparison output S3 emphasized to be a intensity level ''0'' when the video signal S1 is a level L0 or below, an intensity level ''1'' when the signal is between the levels L0 and L1, an intensity level ''2'' when the signal is between the levels L1 and L2, an intensity level ''3'' when the signal is between the levels L2 and L3, and an intensity level ''4'' when the signal is the level L3 or over, appears. The comparison output S3 is stored in a video RAM18. An output of the video RAM18 is converted into an analog signal by a D/A converter 19 and extracted as a video signal S2.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Field of Industrial Application The present invention relates to an image processing device that detects changes in the intensity of a video signal and causes a display to display a desired display in accordance with the changes in intensity.

(B) Prior Art In the past, various image processing devices such as image enhancement devices and binarization devices have been proposed and implemented, which detect changes in the intensity of video signals and display desired images on a display according to the changes in intensity. ing.

FIG. 1 is an explanatory diagram showing, as an example, a case in which a conventional image processing apparatus is used for X-ray fluoroscopy.

In the same figure (al, 1 is an X-ray tube, 2 is a fluorescence multiplier tube,
3 is a lens system, 4 is a TV camera, 5 is a camera controller,
Reference numeral 6 indicates a monitor, and 7 indicates a material to be inspected, for example, a cast steel product.

This device attempts to detect defects such as blowholes, cavities 2, and sand pits in cast steel products 7 from changes in the intensity of video signals obtained by X-ray fluoroscopy.

(for the same figure) is a video signal obtained by X-ray fluoroscopy of the cast steel product 7 shown in FIG. 18+. The intensity of this video signal S1 changes from a black level to a white level in accordance with changes in the thickness of the cast steel product. Portions a and b in the video signal S1 have signal strengths that have changed due to defects A and B included in the S8 steel product.

Therefore, the minute intensity change portion of the video signal S1 is
It is compared in an analog manner with a plurality of preset slice levels LO to 1.3, and an emphasized video signal (when there is 11 slice levels, a binary signal) as shown in Figure tc) is generated.
is obtained.

However, as is clear from FIG. If this is emphasized, minute changes in the video signal in the black level area will not be emphasized.

Therefore, when detecting defects in the thick portion of the cast steel product 7, the slice level must be changed from the black level to the white level region. For example, in the case of a material to be inspected that has various wall thicknesses, such as a vehicle crankshaft, changing the slice level as described above is troublesome and causes a decrease in work efficiency.

(C) Objective An object of the present invention is to provide an image processing device that can simultaneously emphasize or binarize minute changes in the white level and minute changes in the black level of a video signal.

(D) Structure The 'mJ image processing apparatus according to the present invention is an image processing apparatus that detects a change in the intensity of a video signal and causes a display to display a desired display according to the change in intensity. a first storage means for storing slice levels; a memory management means for dividing a storage area of the first storage means into a plurality of blocks; a second storage means for storing a slice level corresponding to each block; It is characterized by comprising a comparison means for comparing the contents of the storage means and the second storage means.

(B) Embodiment FIG. 2 is a block diagram schematically showing the configuration of an embodiment of an image processing apparatus according to the present invention.

In the figure, Xl is an A/D converter that inputs the video signal SL, and 12 is a first converter that stores the digitally converted video signal.
This is an image memory that is a storage means for.

On the other hand, 13 is a synchronization separation circuit which inputs the video signal Sl and separates horizontal and vertical synchronization signals.

Reference numeral 14 denotes a memory management section serving as memory management means for dividing the storage area of the image memory 12 into a plurality of blocks. The memory management unit 14 includes, for example, a counting circuit that counts clock signals in synchronization with the synchronization signal of the video signal S1, a comparator that compares the counted value with a set value, a register that stores the set value, etc. Image memory 1 according to the setting value
By specifying an address within 2, the storage area can be divided arbitrarily.

Reference numeral 15 denotes a slice level register, which is a second storage means, in which slice levels, which are a plurality of threshold values, are arbitrarily set according to each divided block of the image memo January 2. The slice level register 15 includes a register that stores a base slice level serving as a reference and a register that stores other slice levels.

Reference numeral 16 denotes a setting device that provides setting values for dividing the image memory 12 to the memory management section 14 and each slice level to the slice level register 15 as digital values. For example, a IIIP switch or a keyboard is used as the setting device 16.

Reference numeral 17 is a comparator that digitally compares the contents of the image memory code and the contents of the Sliceley-Releso star.

18 is a video RAM that stores the output signal of the comparator 17;
It is. This video RAM 18i; 1 is controlled by the memory management section 14. However, if the response of signal processing such as an A/D converter is sufficiently fast, this video RAM 18 is not necessarily required.

19 is a D/A converter that converts the digital signal stored in the video RAM] 8 into an analog video signal s2.

Next, the operation of the embodiment having the above-described configuration will be explained.

FIG. 3 is an explanatory diagram of the operation of the embodiment shown in FIG. 2.

First, the image memory 12 is divided into appropriate blocks by the setting device 16. For example, assume that the block is divided into blocks I to ■ in the horizontal direction.

Also, for each block, the base slice level LO
and other slice levels L1 to L3 are respectively set. Since the thickness of the material to be inspected is known in advance, the base slice level LO is set to an appropriate level depending on the thickness of each portion. Slice levels Ll to L3 are
It is arbitrarily set depending on the degree of image enhancement or binarization.

Thus, the video signal S1 is stored in predetermined blocks I to (2) of the image memory 12 divided by the memory management section 14. Then, in the comparator 17, the storage contents of each block are determined at the slice level L corresponding to the block.
It is compared with O-L3. FIG. 3 fat shows the state of comparison between the video signal S1 and slice levels L, 0-L3 in each block. However, for convenience of explanation, the video signal S1 is shown in analog form.

When the video signal S1 is below level LO, the intensity level is set to 0; when it is between levels I, 0 and LL, it is set to intensity level 1; when it is between levels L1 and L2, it is set to intensity level 2;
A comparison output S3 is displayed which is emphasized so that the intensity level is 3 when the level is between L2 and L3, and the intensity level is 4 when the level is above 3. This comparison output S3 is stored in the video RAM 18.

The output of the video RAM 1B is converted into an analog signal by the D/A converter 19 and taken out as an enhanced video signal S2 as shown in FIG. 3(b).

Above, we have explained the case where image memo January 2 is divided horizontally, but of course image memo January 2 can also be arbitrarily divided vertically, and the operation in this case is the same as described above. be.

In the above embodiment, since the video signal and the slice level are compared digitally, the slice level setting,
Changes, and furthermore, gamma correction of visibility, etc., can be easily performed. However, the present invention is not limited to digital comparison, but also includes analog comparison.

(F) Effect This invention stores video signals in a storage means having a plurality of arbitrarily divided blocks, and compares the stored contents of each block with a slice level set in advance for each block. This is for image enhancement or binarization.

Therefore, according to the image processing apparatus according to the present invention, it is possible to simultaneously perform image enhancement on slight changes in the video signal in the white level and the black level, so that work related to image processing can be performed very easily.

Further, according to the present invention, since the slice level can be varied depending on each part of the screen where the image is displayed, it is also possible to correct the shading of the image pickup tube.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram illustrating a case in which a conventional image processing device is used for X-ray fluoroscopy, and FIG. 7 and 3 are explanatory diagrams of the operation of the embodiment shown in FIG. 2. 11... A/D converter, 12... Image memory, 14
. . . memory management unit, 15 . . . slice level register, 17 . . . comparator, 19 . . . D/A converter. Patent applicant Shimadzu Corporation Representative Patent attorney Takaharu Ohnishi

Claims (1)

[Claims] (1) An image processing device that detects a change in the intensity of a video signal and causes a display to display a desired display according to the change in intensity, comprising: a first storage means for storing the video signal; and the first storage means. a memory management means that divides the storage area into a plurality of blocks; a second storage means that stores slice levels corresponding to each block; and a comparison between the contents of the first storage means and the second storage means. An image processing device comprising: comparison means.