Moving picture coding system for digital storage media using hybrid coding

Nagata, Atsushi; Inoue, Ikuo; Tanaka, Akiyoshi; Takeguchi, Nobuyasu

doi:10.1016/0923-5965(90)90014-9

Cited by 5 publications

(3 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this case, it is better to apply the motion-estimation algorithm on the input pictures despite not being optimum in reducing the bit rate [21]. Recently this approach has found a wide acceptance in motioncompensated interframe coding for a variety of applications ranging from storage media to HDTV [22]- [23]. Our experiments show that cell interpolation gives better results when motion vectors are calculated directly from the input frames rather than from the prediction frame.…”

Section: Extraction Of the Motion Vectorsmentioning

confidence: 81%

Cell-loss concealment in ATM video codecs

Ghanbari

Seferidis

1993

IEEE Trans. Circuits Syst. Video Technol.

144

View full text Add to dashboard Cite

In this paper methods for the interpolation of lost cells in asynchronous-transfer-mode (ATMI networks are studied. It is shown that use of motion-compensated previous frames gives the best results. The quality of the interpolated pictures improves if the motion vectors truly represent the actual motion in the scene. This is only possible with a two-layer coding scheme, where the motion vectors can be delivered to the decoder through the base-layer guaranteed channel. In derivation of the motion vectors at the encoder, use of uncoded input picture frames outperforms the conventional method of motion extraction from the previous coded pictures, despite the lower bit rate of the latter to the former. Depending on the quality of the base layer and the scene activity, the signal-to-noise ratio (SNR) in the cell-loss-interpolated areas can be improved by up to 10 dB.

show abstract

Section: Extraction Of the Motion Vectorsmentioning

confidence: 81%

Cell-loss concealment in ATM video codecs

Ghanbari

Seferidis

1993

IEEE Trans. Circuits Syst. Video Technol.

144

View full text Add to dashboard Cite

show abstract

“…(8). is reflected in the error function, and, therefore, it is rea- (6) sonable to adaptively select the number of discontinuity planes as the minimal k value such that S(N,k) <Emax. The algorithm for optimal discontinuity detection is given in Fig.…”

Section: Integration Of Block-based Still Image Codersmentioning

confidence: 99%

“…For bit rates of 64 kb/s and up to about 2 Mb/s, the main focus has been on hybrid predictive schemes. [1][2][3][4][5][6][7] The prediction is performed along the time axis and the resulting prediction error signal is coded in the spatial domain using the discrete cosine transform (DCT) 8h1 This is in most cases supplemented by motion compensation for the purpose of improving the prediction part of the coder. Examples of this general scheme can be found in the Consultative Committee on International Telephony and Telegraphy (CCITT) standard H.261 for visual telephony3 at p X 64 kb/s and also in the documents of the Motion Picture Expert Group (MPEG) working on standardization for digital storage of TV-quality images5 at about 1 Mb/s.…”

Section: Introductionmentioning

confidence: 99%

Adaptive temporal decimation for video compression algorithms

Olstad¹

1993

J. Electron. Imaging

View full text Add to dashboard Cite

A new technique for temporally decimating an image soquence is presented where the amount of decimation in the time direction varies with the local temporal activity. The technique is used to reduce the average frame rate ofan image sequence before compression to achieve high-compression ratios. One trivial form of achieving temporal decimation is by periodically dropping whole frames from the image sequence. However, dropping whole frames from the image sequence may cause objectionable temporal aliasing artifacts, especially in regions where temporal activity is high.Hence, to avoid the temporal allasing artifacts, we propose to adaptively adjust the amount of decimation in the time direction depending on the local activity. The temporal decimation procedure can be combined with several strategies for reduction of spatial redundancy. We have utilized subband coding and block-based transform coding for still image compression in our experiments. The proposed International Standards Organization (ISO) standards, the Consultative Committee on International Telephony and Telegraphy (CCITT) H.261, and the Motion Picture Expert Group (MPEG) proposed standard are described, and we illustrate how our contribution fits into these frameworks. The algorithm is demonstrated for a wide range of compression ratios. The examples include CCITT video sequences and medical ultrasound.

show abstract

Global motion estimation for image sequence coding applications

Eisips

Malah

17th Convention of Electrical and Electronics Engineers in Israel

View full text Add to dashboard Cite

This paper describes two algorithms for the estimation of global motion in image sequences. Global motion compensation improves the image prediction while adding only a small amount of side-information in an image sequence coder, thus saving bitrate and/or improving quality. A 3-parameter model is considered for global motion representation, including zoom ratio and horizontal and vertical pan. Both algorithms are based on block displacement estimates and take into account superimposed local motion. The first algorithm selects a set of most reliable block displacements and applies a Least Squares (LS) scheme to obtain an initial estimate of the model parameters out of these displacements. Then a Verification Stage is used to discard blocks whose displacements are not compatible to this estimate. Finally a LS scheme, using only the verified block displacements, is applied to obtain a finer estimate of the model parameters. The second algorithm uses a Hough Transform to separate background blocks whose block displacements are processed by a LS scheme to obtain the model parameters. Simulation results are given for the " Table-Tennis" image sequence containing zooming and show a rate reductkm of over 20% for this sequence.

show abstract

Moving picture coding system for digital storage media using hybrid coding

Cited by 5 publications

References 1 publication

Cell-loss concealment in ATM video codecs

Cell-loss concealment in ATM video codecs

Adaptive temporal decimation for video compression algorithms

Global motion estimation for image sequence coding applications

Contact Info

Product

Resources

About