• Title/Summary/Keyword: integer DCT

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A Study on the H.263 Encoder using Integer DCT (정수 DCT를 이용한 H.263 부호기에 관한 연구)

  • 김용욱;허도근
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.2072-2075
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    • 2003
  • This paper is studied the high speed processing moving picture encodec to compress and encode a moving picture by real time. This is used the new motion vector search algorithm with smallest search point in H.263 encodec, and is applied the integer DCT for the encodec by converting a moving picture. The integer DCT behaves DCT by the addition operation of the integer using WHT and a integer lifting than conventional DCT that needs the multiplication operation of a floating point number. Therefore, the integer DCT can reduce the operation amount than basis DCT with having an equal PSNR because the multiplication operation of a floating point number does not need.

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A study on the Encoding Method for High Performance Moving Picture Encoder (고속 동영상 부호기를 위한 부호화 방법에 관한 연구)

  • 김용욱;허도근
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.8 no.2
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    • pp.352-358
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    • 2004
  • This paper is studied the improvement of performance for moving picture encoder using H.263. This is used the new motion vector search algorithm using a relation with neighborhood search point and is applied the integer DCT for the encoder. The integer DCT behaves DCT by the addition operation of the integer using WHT and a integer lifting than conventional DCT that needs the multiplication operation of a floating point number. Therefore, the integer Dn can reduce the operation amount than basis DCT with having an equal PSNR. The new motion vector search algorithm is showed almost similar PSNR as reducing the operation amount than the conventional motion vector search algorithm. To experiment a compatibility of the integer DCT and the conventional DCT, according to result compare case that uses a method only and case that uses the alternate two methods of the integer DCT or the conventional DCT to H.263 encoder and decoder, case that uses the alternate two methods is showed doing not deteriorate PSNR-and being each other compatible visually than case that uses an equal method only.

A method for intra-prediction in the Integer DCT domain of H.264 (H.264의 integer DCT 영역에서의 Intra-prediction 기법)

  • Ahn, Hyeong-Jin;Oh, Hyung-Suk;Kim, Won-Ha
    • Proceedings of the KIEE Conference
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    • 2008.04a
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    • pp.91-92
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    • 2008
  • 본 논문에서는 기존의 H.264/AVC의 spatial 영역에서 Intra prediction 기법과 달리 H.264/AVC에서 사용하는 Integer DCT 영역에서 Intra prediction 기법을 제안한다. 이를 위하여 Integer DCT 영역에서 Intra prediction을 수행하는 모든 과정을 matrix multiplication으로 표현하여 Intra prediction을 수행하는 matrix를 유도한다. Intra prediction을 수행하는 matrix를 각 모드에 알맞게 설계하고, 이 matrix를 Integer DCT 영역에서 사용할 수 있도록 orthogonal한 Integer matrix를 설계한다. 실험을 통하여 제안한 Integer DCT 영역에서 Intra prediction 기법이 기존의 H.264/AVC의 spatial 영역에서 intra prediction 기법과 성능이 동일하면서 어떻게 matrix multiplication에 연산들을 포함시켜서 단순화 할 수 있는지를 보여주겠다. 또한 H.264/AVC에서 제공하는 intra prediction 각 모드에 대해 계산상 복잡도를 분석하였다.

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An Integer DCT Algorithm for Lossless Audio Coding (무손실 음향부호화를 위한 정수 DCT실현기법)

  • Shin, Jae-Ho;Park, Se-Hyoung
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
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    • v.5 no.1
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    • pp.1-11
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    • 2006
  • Lifting scheme based integer transforms provides very useful properties on the multimedia coding. An integer transform outputs the integer form when the input has integer value. This doesn't produce quantization errors on coding, so integer transforms are adequate to lossless coding, In this paper, we present an integer DCT algorithm which is able to transform audio signal with longer length. Also the proposed method can be easily implemented recursively even though input is long time. We present the method to overcome the poor approximation which is produced by recursive lifting step. And we have applied the proposed integer DCT to lossless audio coding.

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Development of Integer DCT for VLSI Implementation (VLSI 구현을 위한 정수화 DCT 개발)

  • 곽훈성;이종하
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.12
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    • pp.1928-1934
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    • 1993
  • This paper presents a fast algorithm of integer discrete cosine transform(IDCT) allowing VLSI implementation by integer arithmetic. The proposed fast algorithm has been developed using Chen`s matrix decomposition in DCT, and requires less number of arithmetic operations compared to the IDCT. In the presented algorithm, the number of addition number is the same as the one of Chen`s algorithm if DCT, and the number of multiplication if the same as that in DCT at N=8 but drastically decreasing when N is above 8. In addition, the drawbacks of DCT such as performance degradation at the finite length arithmetic could be overcome by the IDCT.

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Optimized Integer Cosine Transform (최적화 정수형 여현 변환)

  • 이종하;김혜숙;송인준;곽훈성
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.9
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    • pp.1207-1214
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    • 1995
  • We present an optimized integer cosine transform(OICT) as an alternative approach to the conventional discrete cosine transform(DCT), and its fast computational algorithm. In the actual implementation of the OICT, we have used the techniques similar to those of the orthogonal integer transform(OIT). The normalization factors are approximated to single one while keeping the reconstruction error at the best tolerable level. By obtaining a single normalization factor, both forward and inverse transform are performed using only the integers. However, there are so many sets of integers that are selected in the above manner, the best OICT matrix obtained through value minimizing the Hibert-Schmidt norm and achieving fast computational algorithm. Using matrix decomposing, a fast algorithm for efficient computation of the order-8 OICT is developed, which is minimized to 20 integer multiplications. This enables us to implement a high performance 2-D DCT processor by replacing the floating point operations by the integer number operations. We have also run the simulation to test the performance of the order-8 OICT with the transform efficiency, maximum reducible bits, and mean square error for the Wiener filter. When the results are compared to those of the DCT and OIT, the OICT has out-performed them all. Furthermore, when the conventional DCT coefficients are reduced to 7-bit as those of the OICT, the resulting reconstructed images were critically impaired losing the orthogonal property of the original DCT. However, the 7-bit OICT maintains a zero mean square reconstruction error.

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Image Compression Using Integer Lapped Orthogonal Transform (정수 직교 겹침 변환을 이용한 이미지 압축)

  • Lee, Sang-Ho;Jang, Jun-Ho;Kim, Young-Seop;Lim, Sang-Min
    • Journal of the Semiconductor & Display Technology
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    • v.8 no.3
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    • pp.45-50
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    • 2009
  • Recently, block-based transforms, like discrete cosine transform (DCT), have been widely used in image and video coding standards, but block-based transforms have a weak point with blocking effect. However, the integer lapped orthogonal transform (ILOT) is a tool for block-based coding with bases functions that overlap near blocks, so it has a strong point against blocking effect. Although it has slightly higher arithmetic complexity than the DCT, the coding gain is significantly higher with much less blocking artifacts. This paper introduces the integer lapped orthogonal transforms and discrete cosine transform. And we compare the performance of DCT with ILOT which is proposed a new efficient method for image coding applications.

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A Study on the Fast Computational Algorithm for the Discrete Cosine Transform(DCT) via Lifting Scheme (리프팅 구조를 경유한 고속의 DCT 계산 알고리즘에 관한 연구)

  • Inn-Ho Jee
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.23 no.6
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    • pp.75-80
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    • 2023
  • We show the design of fast invertible block transforms that can replace the DCT in future wireless and portable computing application. This is called binDCT. In binDCT, both the forward and the inverse transforms can be implemented using only binary shift and addition operation. And the binDCT inherits all desirable DCT characteristics such as high coding gain, no DC leakage, symmetric basis functions, and recursive construction. The binDCT also inherits all lifting properties such as fast implementations, invertible integer-to-integer mapping, in-place computation. Thus, this method has advantage of fast implementation for complex DCT calculations. In this paper, we present computation costs and performance analysis between DCT and binDCT using Shapiro's EZW.

Lossless Audio Coding using Integer DCT

  • Kang MinHo;Lee Sung Woo;Park Se Hyoung;Shin Jaeho
    • Proceedings of the IEEK Conference
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    • summer
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    • pp.114-117
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    • 2004
  • This paper proposes a novel algorithm for hybrid lossless audio coding, which employs integer discrete cosine transform. The proposed algorithm divides the input signal into frames of a proper length, decorrelates the framed data using the integer DCT and finally entropy-codes the frame data. In particular, the adaptive Golomb-Rice coding method used for the entropy coding selects an optimal option which gives the best compression efficiency. Since the proposed algorithm uses integer operations, it significantly improves the computation speed in comparison with an algorithm using real or floating-point operations. When the coding algorithm is implemented in hardware, the system complexity as well as the power consumption is remarkably reduced. Finally, because each frame is independently coded and is byte-aligned with respect to the frame header, it is convenient to move, search, and edit the coded data.

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Orthogonal Integer Transform (직교 정수형 변환)

  • 이종하;곽훈성
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.1
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    • pp.64-71
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    • 1994
  • In this paper, we propose orthogonal integer transform(OIT) with general form. Considering the orthogonality and magnitude value order of the DCT Matrix whose performance is found to be close to that of the KLT, known to be optimal. The proposed OIT matrix is composed of values minimizing Hibert-Schmidt norm among integer values which satisfy the condition of orthogonality and the relative magnitudes of the DCT matrix. Comparing the OIT with the DCT, CMT, and ICT in error characteristics, transform efficiency, and maximum reducible bit, it is shown that the performance of the OIT compares more closely to that of the KLT relative to the performances of the DCT, CMT, and ICT when N=8.

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