• Title/Summary/Keyword: Intra-motion

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Efficient Rate Control by Lagrange Multiplier Using Adaptive Mode Selection in Video Coding (비디오 코팅시 Lagrage 승수를 조정하여 적응 모드 선택에 따른 비트율의 제어)

  • Ryu, Chul;Kim, Seung P.
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.1B
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    • pp.77-88
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    • 2000
  • This paper presents an approach for rate control by adaptively selecting macroblock modes in video coding.The problem of rate control has been investigated by many authors where quantizer level is adjustedbased on the buffer fullness. The proposed approach is different fron the previous ones [4] id that it finds the optimal decision curve rather than finding a set of the modes. Proposed algorithm extends the coding decision options for rate control to motion/no-motion compensation as well as inter/intra decisions. Instead of having a fixed motion/no-notion compensation or inter/intra decision curve, one can utilize an adaptive decision curvebased on the characteristics of input frames so that the PSNR at a given bit rate is maximized. Therefore, the proposed approach provides better rate control than simple quantizer feedback approach interns of visual quality. The curve is obtained by utilizing simulated annealing optimization technique. Thealgorithm is implemented and simulations are compared with other approaches within H.261 video codec.

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Changes in Range of Motion after Intra-Articular Corticosteroid Injection in Frozen Shoulder: A Retrospective 3-Month Follow-Up Study (동결견 환자에서 관절강내 스테로이드 주사 후 관절가동범위의 변화)

  • Cho, Hyoung Jun;Yoon, Seung-Hyun;Kim, Minchul;Kim, Dae Hwan
    • Clinical Pain
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    • v.18 no.2
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    • pp.76-81
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    • 2019
  • Objective: To examine (1) the degree of reduction of passive range of motion (PROM) on the affected side compared to that on the unaffected side and (2) the degree of increase in PROM following intra-articular corticosteroid injection (IACI) in patients with frozen shoulder. Method: The medical records of 120 patients with frozen shoulder were retrospectively reviewed. PROM of the unaffected and affected shoulder (flexion, extension, abduction, internal rotation, external rotation) was compared, and changes in PROM of the affected shoulder after a single IACI (triamcinolone 20 mg) were evaluated after 12 weeks. Results: At the time of diagnosis, PROM of the affected shoulder was most limited in external rotation, followed by internal rotation, abduction, extension, and flexion, compared to that of the unaffected shoulder. Compared to before IACI, PROM of external rotation demonstrated the greatest increase compared to all the other movements after IACI. Conclusion: Limitation in PROM of the frozen shoulder at the time of diagnosis was greatest for external rotation. Moreover, external rotation experienced the greatest improvement after IACI. Our findings should help to further clarify the clinical characteristics of frozen shoulder, aid in its diagnosis, and allow the prediction of the effects of IACI.

Analgesia After Subacromial Arthroscopy: Prospective Double-blind Study of Continuous Mixed Intra-bursal Infusion with Morphine and Bupivacaine and placebo (견봉하 관절경 수술 후 진통 작용: 모르핀과 국소마취제 혼합제와 위약의 점액낭 내 지속 주입에 대한 전향적 이중 맹검 연구)

  • Park Jin-Young;Lee Kwan-Woo;Kim Yun;Yoo Moon-Jib
    • Clinics in Shoulder and Elbow
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    • v.3 no.2
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    • pp.102-108
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    • 2000
  • The aim of this study is to determine if intra-bursal morphine and Bupivacaine mixed infusion provided useful analgesia after subacromial arthroscopic operation. At the end of the subacromial arthroscopy, continuous intra-bursal infusion catheter was inserted. In a double-blind randomized trial, Sixty patients were allocated to one of two groups: placebo group(n=30) received continuous saline infusion. Study group received mixed 5㎖ of 0.5% Bupivacaine, 2㎎ of morphine and 0.05㎖ of 1/1000 epinephrine as bolus and mixed solution of 40㎖ of 0.5% Bupivacaine and 8㎎ of morphine as maintenance dose with continuous infusion pump(0.5㎖ hourly). In the placebo group, two patients were discontinued due to leakage and catheter coming out each. Intensity of pain was evaluated preoperatively and postoperatively for 3 days by 10 graded visual analogue scale. Night pain, pain on motion, sleep disturbance, lying on painful shoulder and amounts of intramuscular pain killer were recorded. Analgesic effect for pain was cleared at 1st and 2nd postoperative day and there was less sleep disturbance for 3 days postoperatively in study group. There was no difference in pain on motion postoperatively. In study group, less pain killers were used in the first 48 hours postoperatively. The continuous intra-bursal infusion decreased perception of pain at resting stage and reduced supplemental analgesic requirement for 2 days postoperatively.

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The Effects of Combined Exercise Program to Intra-City Bus Driver With Chronic Neck Pain : Case Report (만성 경부통을 가진 시내버스 운전기사에게 복합 운동프로그램의 효과 : 사례연구)

  • Ahn, Seung-won;Jung, Young-june
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.21 no.1
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    • pp.49-56
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    • 2015
  • Background: Although many of those who drive for a living are exposed to repetitive and awkward posture and whole body vibration which cause them cumulative trauma disorder, therapeutic studies related to the problems from the transport unit are still somewhat inadequate. The purpose of this case report is to identify the effect of combined exercise program on patients suffering chronic neck pain caused by long hour of intra-city bus driving. Method: A total of 4 subjects are selected as patients, all of whom have more than 10 years of experience in intra-city bus transportation services. These people have suffered from neck pain for years. We ran the combined exercise program 3 times a week for 4 weeks and respectively evaluated the results after the 2nd and 4th week. We implemented conventional physiotherapy for 40 minutes, another 40 minutes of combined exercise program, and then educated the patients to enable themselves to do active stretching program as a home program. The combined exercise program contained 3 different stages. 1st stage: active stretching program, 2nd stage combined stabilization exercise and strengthening exercise, 3rd stage: proprioceptive exercise Result: After 4 weeks of intervention, there was enhance in the range of motion. $12^{\circ}$ increase in flexion, $10^{\circ}$ in extension, $6^{\circ}$ in lateral flexion respectively, and $10^{\circ}$ in rotation on average. VAS(visual analgue scale) decreased by 33% on average, NDI(neck diability index) by 28% and fatigability by 23%. Conclusion: There were improved results in the range of motion, NDI, VAS, and in fatigability after applying combined exercise program to intra-city bus drivers exposed to whole body vibration and cumulative trauma disorder.

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An Analysis of Intra-Fractional Movement during Image-Guided Frameless Radiosurgery for Brain Tumor Using CyberKnife (사이버나이프를 이용한 무고정틀 두개 방사선 수술 중 발생한 환자의 치료 중 움직임 분석)

  • Kang, Ki Mun;Chai, Gyu Young;Jeong, Bae Gwon;Ha, In-Bong;Park, Kyung Bum;Jung, Jin-Myung;Lim, Young Kyung;Jeong, Hojin
    • Progress in Medical Physics
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    • v.23 no.3
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    • pp.169-176
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    • 2012
  • Frameless method in brain radiosurgery has advantages relative to rigid head-frame method in terms of patient friendly and flexible application of multi-fractionation. However, it has also disadvantages and the most negative point is that it cannot control the patient motion during treatment as lowly as the level of the frame-based radiosurgery, which could affect to the treatment accuracy. In the present study, we analyzed the geometric uncertainty of the intra-fraction motion using the actual treatment records of 294-CyberKnife treatments for brain tumors. Based on the analysis, we statistically presented the magnitude of intra-fraction motion in frameless radiosurgy. The result could provide the quantitative information to determine the adequate treatment margins to compensate the intra-fraction movements.

Inter-Intra Motion Estimation in Wavelet based Codec (웨이블릿 코덱에서의 Inter-Intra 움직임 예측 기법)

  • 이주경;김충길;강정구;정기동
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.04d
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    • pp.187-189
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    • 2003
  • 웨이블릿 변환에 기반한 동영상 코덱에서의 움직임 예측 기법은 OCT 기반 코덱과 유사하게 이전 프레임과의 움직임 예측을 통하여 수행된다. 그러나, 현재 프레임이 이전 프레임을 참조하므로 네트워크상의 전송시 이전 프레임에 발생한 오류가 전달되는 오류 전파의 문제도 발생하게 된다. 본 논문에서는 웨이블릿 변환된 프레임의 특성을 이용하여 최상위 레벨의 LL 부대역만 이전 프레임과의 움직임 예측을 수행하고, 나머지 부대역에 대하여 프레임 내의 상위레벨의 부대역이 하위 부대역을 창조하여 예측 및 보상을 수행하여 오류전파의 가능성을 최소화하는 Inter-Intra ME 동영상 코덱을 제안한다 제안된 움직임 예측을 사용하여 MAD(Mean-Absolute Differences)를 측정한 결과, 프레임간 변화가 심한 경우에는 제안된 기법과 이전 프레임의 부대역을 참조한 기법 사이의 압축율은 유사하게 나타났으며, 변화가 적은 경우에는 이전 프레임을 참조하는 것의 압축율이 높게 나타났다. 그러나, 네트워크 전송시 발생하는 오류전파에는 제안된 기법의 성능이 우수한 것으로 나타났다.

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Fast Intra Mode Selection Algorithm Based on Edge Activity in Transform Domain for H.264/AVC Video (변환영역에서의 에지활동도에 기반한 H.264/AVC 고속 인트라모드 선택 방법)

  • Seo, Jae-Sung;Kim, Dong-Hyung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.8C
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    • pp.790-800
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    • 2009
  • For the improvement of coding efficiency, the H.264/AYC standard uses new coding tools such as 1/4-pel-accurate motion estimation, multiple references, intra prediction, loop filter, variable block size etc. Using these coding tools, H.264/AYC has achieved significant improvements from rate-distortion point of view compared to existing standards. However, the encoder complexity was greatly increased due to these coding tools. We focus on the complexity reduction method of intra macroblock mode selection. The proposed algorithm for fast intra mode selection calculates the edge activity in transform domain, and performs fast encoding of intra frame in H.264/AYC through the fast prediction mode selection of intra4x4 and chrominance blocks. Simulation results show that the proposed method saves about 59.76% for QCIF sequences and 65.03% for CIF sequences of total encoding time, while bitrate increase and PSNR decrease are very small.

Scene Change Detection Algorithm on Compressed Video

  • Choi Kum-Su;Moon Young-Deuk
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.442-446
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    • 2004
  • This paper propose scene change detection algorithm using coefficient of forward prediction macro-block, backward prediction macro-block, and intra-coded macro-block on getting motion estimation. Proposed method detect scene change with correlation according picture type forward two picture or forward and backward two picture on video sequences. Proposed algorithm is high accuracy and can detect all scene change on video, and detect to occur scene change on P, B, I-picture.

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Rate-Distortion Oprimized Error-Resilient Intra Update in MPEG-4 Video Coding (MPEG-4 동영상 압축에서 비트율과 오류 내성을 고려한 인트라 업데이트)

  • Kim, Woo-Shik;Park, Rae-Hong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.39 no.6
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    • pp.591-601
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    • 2002
  • Motion compensation is a powerful method to compress an image sequence. Its main drawback is that once an error is occurred, the error propagates through the frames. Recently, the intra update method was proposed to stop the error propagation at the expense of reduction in compression efficiency. This paper proposes an intra update method based on a rate-distortion optimization in error prone environments. The rate and the distortion are estimated using the Lagrangian optimization to select the coding mode and the quantization step size. The proposed method is applied to MPEG-4 codec, and the experimental results show that it is robust to the error such as packet losses comparing with the conventional ones.

An Improvement in Intra-Slice Low Delay Video Coding for Digital TV Broadcasting (디지틀 TV 방송을 위한 저지연 intra-slice 영상 부호화 방식의 개선 방법)

  • 권순각;김재균
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.12
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    • pp.2376-2385
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    • 1994
  • In receiving the digital TV signal, both decoding delay and the channel hopping delay are very critical factors in applications. The intra-slice coding in the MPEG-2 SIMPLE PROFLE of No B-picture is one of the primary methods for short delay time in video decoding. It has the advantage of short decoding delay, but has the drawback of long channel hopping delay time. In this paper, we propose a method to reduce the channel delay with negligible loss in SNR performance. It is shown that dividing pictures into several regions of slices and adding some restriction in motion vector search for inter-frame coding. hence the random acess points are effectively increased. and the channel hopping delay is reduced.

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