Scalable Object-Based Indexing of HD Videos: A JPEG2000- Oriented solution

Video indexing technique is crucial in multimedia applications. In the case of HD (High Definition) Video, the principle of scalability is of great importance. The wavelet decomposition used in the JPEG2000 standard provides this property. In this paper, we propose a scalable descriptor based on objects. First, a scalable moving object extraction method is constructed. Using the wavelet data, it relies on the combination of a robust global motion estimation with a morphological color segmentation at a low spatial resolution. It is then refined using the scalable order of data. Second, a descriptor is built only on the objects found at the previous step. This descriptor is based on multiscale histograms of wavelet coefficients of moving object

Fast In-Band motion Estimation with Variable Size Block Matching

none4D. Maestroni; A. Sarti; M. Tagliasacchi; S. TubaroMaestroni, Davide; Sarti, Augusto; Tagliasacchi, Marco; Tubaro, Stefan

FAST IN-BAND MOTION ESTIMATION WITH VARIABLE SIZE BLOCK MATCHING

In this paper we propose a fast motion estimation technique that works in the wavelet domain. The computational cost of the algorithm turns out to be proportional to the linear size of the search window instead of its area. We complete our proposal with a variable-size block-matching scheme in the wavelet domain. We integrated the motion estimation algorithm in a fully-scalable wavelet in-band prediction coder inspired by the IB-MCTF (In-Band Motion Compensation Temporal Filtering) proposed in [1]. Comparative tests prove that our coder provides the same quality level than IB-MCTF at a very reduced computational cost. Moreover, although our method turns out to match the performance of MCTF-EZBC [2] in terms of PSNR, it clearly outperforms it in terms of perceptual quality, as it is completely free from blocking artifacts. 1