JP2008029695A - Ultrasonic diagnostic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide ultrasonic diagnostic equipment which carries out digital-recording of a moving image without a drastic deterioration in image quality even when a display content is changed greatly during video recording. <P>SOLUTION: The ultrasonic diagnostic equipment is equipped with an image recording function for compressing and recording ultrasonic moving images generated successively through ultrasonic scanning by a probe in MPEG 2 format. When an operation accompanying great changes in a display content, such as a change of display mode, enlargement or reduction of an image or the like, is carried out (S12), the ultrasonic diagnostic equipment sends a signal showing the timing of display change (S13) to an encode section and generates an I picture according to the timing (S14). With such a configuration, a deterioration in image quality is suppressed by synchronizing the timings of the great display change and the generation of the I picture and distortion of images is prevented even when the recorded images are reproduced by frame reproduction or the like. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an ultrasonic diagnostic apparatus, and more particularly to an ultrasonic diagnostic apparatus that includes means for digitally recording an ultrasonic moving image generated from an echo signal.

  An ultrasonic diagnostic apparatus is an apparatus for imaging information inside a subject using ultrasonic transmission / reception waves, and generates an ultrasonic image from echo signals acquired by a probe in contact with the subject. The image can be displayed on the monitor. In such an ultrasonic diagnostic apparatus, it is generally possible to capture an ultrasonic moving image by repeatedly performing ultrasonic scanning and image generation at predetermined intervals, and further, a VCR (Video Casette Recorder). For example, those having a function of recording the moving image by the above-described method are known.

  Furthermore, in recent years, an ultrasonic diagnostic apparatus having a function of digitally recording the ultrasonic moving image on a hard disk or a DVD has been widely used (see, for example, Patent Document 1). At the time of digital recording of such an ultrasonic moving image, image data is compressed in order to reduce the amount of data. At this time, in the MPEG2 system, the spatial redundancy of the image is reduced (that is, compression within the frame). In addition, temporal redundancy is reduced (ie, inter-frame compression).

  Such compression / decompression of moving images is usually performed with a set of a plurality of frames called GOP (Group Of Pictures) as a unit. In general, a GOP is composed of three types of frames called an I picture (Intra Picture), a P picture (Predictive Picture), and a B picture (Bi-directionally predictive Picture). An I picture is a frame that has been subjected only to intra-frame compression, and serves as a reference frame when performing the inter-frame compression. A P picture is a frame that has been subjected to inter-frame compression by forward prediction based on a difference from a past I picture or P picture in addition to intra-frame compression, and a B picture This is a frame that has been subjected to inter-frame compression by bi-directional prediction using the difference between the preceding and subsequent I-pictures or P-pictures. In the case of MPEG-2 for DVD-Video, the configuration of each GOP is generally 15 frames as a unit and “P picture distance” is 3 frames as in “IBBPBBPBBPBBPBB”.

JP 2004-267301 A ([0002] to [0004])

  As described above, the P picture is generated based on the past I picture or P picture, and the B picture is generated based on the past and future I pictures or P pictures. Accordingly, when an operation accompanied by a large change in display content such as a change of the image display mode or enlargement / reduction of the display image is performed during the recording of the ultrasonic moving image, the timing of the display change by the operation and the I picture If the timings for generating are not matched, inter-frame compression is performed between frames with extremely low correlation. For this reason, the image quality of the portion deteriorates, and the image may be disturbed when frame-by-frame playback is performed for detailed observation.

  The present invention has been made to solve such a problem, and an object of the present invention is an ultrasonic apparatus having a function of digitally recording an ultrasonic moving image, which is large during recording of a moving image. It is an object of the present invention to provide an ultrasonic diagnostic apparatus that does not cause a significant deterioration in image quality even when display contents are changed.

An ultrasonic diagnostic apparatus according to the present invention, which has been made to solve the above-described problems, generates an ultrasonic moving image using ultrasonic transmission / reception waves, and has the function of digitally recording the moving image. In the diagnostic device,
a) an ultrasonic moving image generating means for generating an ultrasonic moving image signal from an echo signal acquired by performing ultrasonic transmission / reception on a subject at a predetermined interval;
b) Processing the ultrasonic moving image signal to generate a compressed moving image signal composed of a plurality of frame groups including a reference frame subjected to only intra-frame compression and a prediction frame subjected to intra-frame compression and inter-frame compression. Encoding means,
c) a recording means for recording the compressed video signal;
d) input means for receiving instructions from the user;
e) When a predetermined display change instruction is input from the input means, a control means for instructing the encoding means to use the first frame generated after the display change by the instruction as the reference frame;
It is characterized by having.

  Here, the predetermined display change instruction is an operation accompanied by a large image change, for example, a display mode change instruction such as a change from B (Brightness) mode display to B (Brightness) / D (Doppler) mode display, An instruction for enlarging / reducing an image can be given, but is not limited thereto. Further, the encoding means may use any compression format as long as it uses both intra-frame compression and inter-frame compression in addition to the above-mentioned MPEG2 format compression.

  According to the ultrasonic diagnostic apparatus of the present invention having the above-described configuration, when an instruction for changing the image display size, changing the display mode, or the like is given from the user during recording of an ultrasonic moving image, the instruction is based on the instruction. The timing of the display change is transmitted to the encoding means, and the moving image is compressed so that the frame corresponding to the timing becomes the reference frame for inter-frame compression (I picture in MPEG2). In this way, by synchronizing the significant change of the display contents and the generation timing of the reference frame, only the image that continuously changes from the reference frame to the next reference frame is configured. For this reason, original image data can be compressed and recorded without causing major deterioration, and image disturbance can be prevented during frame-by-frame playback and the like.

  Hereinafter, the best mode for carrying out an ultrasonic diagnostic apparatus according to the present invention will be described based on examples.

  FIG. 1 shows a main configuration of an ultrasonic diagnostic apparatus 10 according to the present embodiment. The probe 11 is in contact with the body surface of the subject and transmits and receives ultrasonic waves. The transmission / reception unit 12 controls the transmission and reception of ultrasonic waves by the probe 11. The echo signal received by the probe 11 is sent to the beamformer 14 via the transmission / reception unit 12 and the A / D conversion unit 13. In the beam former 14, echo signals received by the ultrasonic transducers in the probe 11 are combined into a single beam signal. The beam signal is subjected to logarithmic compression and detection in the vector image processing unit 15, and further, coordinate conversion and interpolation processing are performed in a digital scan converter (“DSC” in the drawing) 17. The image signal generated as described above is stored in the image memory 19, sequentially read out to the D / A converter 20, and displayed on the screen of the monitor 21. By repeatedly executing the above steps, the image on the monitor 21 is updated at a predetermined time interval and visually recognized as a moving image.

  When the ultrasonic moving image is recorded, the output of the image memory 19 is sent to the encoding unit 24, and after the intra-frame compression and the inter-frame compression are performed in the encoding unit 24, a hard disk (HDD) or an optical disk (DVD) is recorded. ) And the like. Further, when the moving image is reproduced, the compressed moving image signal recorded in the recording unit 25 is expanded by the decoding unit 26. The expanded moving image signal is input to the image memory 19 and sent to the monitor 21 via the D / A converter 20. The operation of each unit is controlled by the control unit 22, and further, an instruction from the user is input by the input unit 23 connected to the control unit 22.

  Hereafter, the operation | movement at the time of the moving image recording in the ultrasonic diagnosing device 10 of a present Example is demonstrated using the flowchart of FIG. First, when an instruction to start recording is given by a user performing a predetermined operation from the input unit 23 during ultrasonic scanning, the control unit 22 instructs the image memory 19 to output an image signal to the encoding unit 24. At the same time, the encoder 24 is instructed to compress the image signal. Upon receiving the instruction, the encoding unit 24 performs intra-frame compression, or intra-frame compression and inter-frame compression, on the image signal output from the image memory 19, and outputs the processed signal to the recording unit 25 (step). S11). At this time, the compression of the moving image is performed with 15 frames as one unit (GOP), and each GOP is composed of a combination of “IBBPBBPBBPBBPBB” having one I picture at the head (FIG. 3A). As described above, an I picture is a frame that has been subjected to spatial compression only by intra-frame compression, and is used as a reference frame for temporal compression. The P picture and the B picture are frames subjected to temporal compression by inter-frame compression in addition to the spatial compression. P picture is subjected to inter-frame compression by forward prediction using past I picture or P picture, and B picture is subjected to inter frame compression by bi-directional prediction using past and future I picture or P picture. Is done.

  During recording of such a moving image, the presence / absence of a predetermined display change operation is always monitored (step S12), and the user instructs the input unit 23 to change the display mode and to enlarge / reduce the image. In the case (“Y” in step S12), the control unit 22 controls the transmission / reception unit 12, the vector image processing unit 15, the DSC 17 and the like according to the instruction, and indicates the timing at which the instruction is reflected in the generated image. A signal (hereinafter referred to as “timing signal”) is sent to the encoding unit 24 (step S13). Upon receiving the timing signal, the encoding unit 24 sets the first frame generated after the display change based on the timing as an I picture, and performs only spatial compression by intra-frame compression on the frame to the recording unit 25. Recording is performed (step S14). Therefore, in the GOP composed of the 15 frames as described above, in addition to the top frame, the frame corresponding to the display change is the I picture (FIG. 3B). Thereafter, steps S11 to S14 are repeatedly executed until an instruction to end recording is given from the user (that is, until “Y” is determined in step S15).

  The moving image recorded as described above is composed only of images that continuously change from the I picture to the next I picture, and there is no significant image change. It is possible to prevent the image quality from deteriorating and to prevent the image from being disturbed during frame-by-frame playback. Note that such moving image recording is performed in the case where an image generated while performing ultrasonic scanning is recorded almost in real time, and an image signal stored in the vector cine memory 16 or the video cine memory 18 is used as the image memory 19. The present invention can be similarly applied to the case of sequentially reading and recording.

  The ultrasonic diagnostic apparatus according to the present invention has a configuration in which the encoding unit 24, the decoding unit 26, and the recording unit 25 are built in the ultrasonic diagnostic apparatus 10 as described above, and a moving image is recorded on the recording apparatus 30 provided outside. May be recorded. An example of such an ultrasonic diagnostic apparatus is shown in FIG. In addition, the same code | symbol is attached | subjected about the structure similar to FIG. 1, and description is abbreviate | omitted suitably.

  The ultrasonic diagnostic apparatus 10 of this embodiment has an analog video output function, and can transmit and receive image signals and control signals to and from external devices via the interface units 27 and 31. The control signal output from the control unit 22 is input to the recording control unit 32 in the recording device 30 via the interface units 27 and 31, and the encoding unit 33 and the recording unit 34 provided in the recording device 30 according to the instruction. The operation of the decoding unit 35 is controlled. Further, the ultrasonic moving image signal output from the image memory 19 is analog-converted by the D / A conversion unit 20 and then sent to the recording device 30 via the interface units 27 and 31. The moving image signal input to the recording device 30 is digitally converted by an A / D conversion unit (not shown), then compressed by the encoding unit 33, and the compressed moving image signal is recorded in the recording unit 34. Further, when reproducing the moving image, the compressed moving image signal recorded in the recording unit 34 is read out and decompressed by the decoding unit 35, and ultrasonic waves are transmitted from the interface unit 31 through a D / A conversion unit (not shown). It is output to the diagnostic device 10.

  As described above, even when the moving image signal is output to the recording device 30 provided outside the ultrasonic diagnostic apparatus 10, the moving image is recorded in the same procedure as in the flowchart. That is, when the user performs a predetermined operation with the input unit 23 during ultrasonic scanning with the probe 11, the control unit 22 instructs the image memory 19 to output an image to the recording device 30, and further, the interface unit A control signal instructing compression and recording of the image is sent to the recording control unit 32 via 27 and 31. Thereafter, when the user gives an instruction to change the display mode or enlarge / reduce the image while recording the ultrasonic moving image, the control unit 22 instructs the transmission / reception unit 12, the vector image processing unit 15, the DSC 17, or the like. , And a signal (timing signal) indicating the timing of image change due thereto is sent to the recording control unit 32 via the interface units 27 and 31. The recording control unit 32 that has received the timing signal controls the encoding unit 33 based on the timing signal to compress and record the frame corresponding to the image change as an I picture.

  The best mode for carrying out the present invention has been described above based on the embodiments. However, the present invention is not limited to the above embodiments, and appropriate modifications are allowed within the scope of the gist of the present invention. Is. For example, in the above embodiment, the operation for changing the display mode and the operation for enlarging / reducing the image are given as the operations for generating the I picture, but other operations may be used for generating the I picture. It is also possible to adopt a configuration in which the user can freely add / delete such an operation for generating an I picture.

The block diagram which shows the principal part structure of the ultrasonic diagnosing device which concerns on the 1st Example of this invention. 6 is a flowchart showing an operation at the time of moving image recording in the ultrasonic diagnostic apparatus of the embodiment. It is a figure which shows the structure of GOP in the ultrasonic diagnosing device of the Example, Comprising: (a) shows the structure of GOP at the time of normal compression, (b) is the structure of GOP when a display change process is performed Indicates. The block diagram which shows the principal part structure of the ultrasonic diagnosing device which concerns on the 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Ultrasonic diagnostic apparatus 11 ... Probe 12 ... Transmission / reception part 13 ... A / D conversion part 14 ... Beam former 15 ... Vector image processing part 16 ... Vector cine memory 17 ... DSC
18 ... Video cine memory 19 ... Image memory 20 ... D / A conversion unit 21 ... Monitor 22 ... Control unit 23 ... Input unit 24, 33 ... Encoding unit 25, 34 ... Recording unit 26, 35 ... Decoding unit 30 ... Recording device 27 31 ... Interface unit 32 ... Recording control unit

Claims (2)

In an ultrasonic diagnostic apparatus having a function of generating an ultrasonic moving image using transmission and reception of ultrasonic waves and digitally recording the moving image,
a) an ultrasonic moving image generating means for generating an ultrasonic moving image signal from an echo signal acquired by performing ultrasonic transmission / reception on a subject at a predetermined interval;
b) Processing the ultrasonic moving image signal to generate a compressed moving image signal composed of a plurality of frame groups including a reference frame subjected to only intra-frame compression and a prediction frame subjected to intra-frame compression and inter-frame compression. Encoding means,
c) a recording means for recording the compressed video signal;
d) input means for receiving instructions from the user;
e) When a predetermined display change instruction is input from the input means, a control means for instructing the encoding means to use the first frame generated after the display change by the instruction as the reference frame;
An ultrasonic diagnostic apparatus comprising: In an ultrasonic diagnostic apparatus having a function of generating an ultrasonic moving image using transmission and reception of ultrasonic waves, outputting the moving image to a moving image recording apparatus provided outside, and performing digital recording,
a) an ultrasonic moving image generating means for generating an ultrasonic moving image signal from an echo signal acquired by performing ultrasonic transmission / reception on a subject at a predetermined interval;
b) recording device control means for generating a control signal for controlling the moving image recording device;
c) output means for outputting the ultrasonic moving image signal and the control signal to the moving image recording apparatus;
d) input means for receiving instructions from the user;
Have
The moving image recording apparatus is a compressed moving image including a plurality of frame groups including a reference frame obtained by processing the ultrasonic moving image signal and performing only intra-frame compression and a predicted frame subjected to intra-frame compression and inter-frame compression. Comprising: an encoding means for generating an image signal; and a recording means for recording the compressed moving image signal,
When a predetermined display change instruction is input from the input means, the recording apparatus control means instructs the encoding means to use the first frame generated after the display change by the instruction as the reference frame. A characteristic ultrasonic diagnostic apparatus.

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