Sun Patent Trust

Panasonic Intellectual Property Corporation of America

Velos Media, LLC

Semih Esenlik

Matthias Narroschke

Thomas Wedi

Anand Meher Kotra

Steffen Kamp

An image decoding method for decoding a bitstream including a coded signal resulting from coding tiles and slices into which an image is partitioned, the method including decoding the coded signal, wherein each of the slices is either a normal slice having, in a header, information used for an other slice or a dependent slice which is decoded using information included in a slice header of another slice, and when the normal slice starts from a position other than a beginning of a first tile, a second tile coded next to the first tile does not start from the dependent slice.

Image decoding method, image coding method, image decoding apparatus, image coding apparatus, and image coding and decoding apparatus

An image includes a plurality of rows of largest coding units (LCUs). Encoding the image includes determining whether or not wavefront parallel processing is enabled, and partitioning the plurality of rows of LCUs to comprise a normal slice and a group of dependent slices. The normal slice includes at least one LCU, and the group of dependent slices includes at least one LCU and consists of every dependent slice that uses information from a slice header of the normal slice for encoding. Based on the determination that wavefront parallel processing is enabled, the partitioning of the plurality of rows of LCUs is restricted such that a last LCU in the group of dependent slices belongs in a same row as a first LCU of the normal slice when the first LCU of the normal slice is not a first LCU of the row.

The present disclosure relates to deblocking filtering which is applicable to smoothing the block boundaries in an image or video coding and decoding. In particular, the deblocking filtering is either strong or weak, wherein the clipping is performed differently in the strong filtering and the weak filtering.

Efficient rounding for deblocking

A dependency indication is signaled within the beginning of a packet, that is, within the adjacent of a slice header to be parsed or a parameter set. This is achieved, for example, by including the dependency indication at the beginning of the slice header, preferably after a syntax element identifying the parameter set and before the slice address, by including the dependency indication before the slice address, by providing the dependency indication to a NALU header using a separate message, or by using a special NALU type for NALUs carrying dependent slices.

Image coding method, image decoding method, image coding apparatus, image decoding apparatus, and image coding and decoding apparatus

The present disclosure relates to deblocking filtering, which may be advantageously applied for block-wise encoding and decoding of images or video signals. In particular, the present disclosure relates to an improved memory management in an automated decision on whether to apply or skip deblocking filtering for a block and to selection of the deblocking filter. The decision is performed on the basis of a segmentation of blocks in such a manner that memory usage is optimized. Preferably, the selection of appropriate deblocking filters is improved so as to reduce computational expense.

Low complex deblocking filter decisions

An image includes a first row of largest coding units (LCUs) and a second row of LCUs that is after the first row of LCUs. Encoding the image includes determining that wavefront parallel processing is enabled, and partitioning the first row of LCUs and the second row of LCUs so as to comprise a normal slice and a group of dependent slices. The normal slice is at a position on the first row of LCUs that is not at the beginning of the first row of LCUs. The group of dependent slices includes every dependent slice that uses information from the normal slice for encoding. Based on the determination that wavefront parallel processing is enabled and the normal slice being at a position that is other than the beginning of the first row of LCUs, the partitioning of the first row of LCUs and the second row of LCUs is performed such that an entirety of the group of dependent slices is included in the first row of LCUs.

The present invention provides an improved video encoding and decoding method, which maintains the advantages of LCU-based filter parameter signaling as compared to frame-based filter parameter signaling, but considerably reduces signaling overhead. Therefore, signaling syntax is modified by grouping LCUs (Largest Coding Units) together for signaling employing a mapping function. Consequently, filter parameters no longer need to be signaled for each single LCU, but for a group of several LCUs. The syntax structure of the invention avoids redundancies present in the state of the art as far as possible and thus increases the information content of the syntax elements. At the decoder side, the mapping function is applied to infer information about the filter parameters to be applied to a current LCU from information encoded in different syntax structures.

Growing community of inventors

Nazilli, Turkey

Semih Esenlik