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.

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.

Disclosed are methods and apparatuses for image data encoding/decoding. A method for decoding a 360-degree image includes the steps of: receiving a bitstream obtained by encoding a 360-degree image; generating a prediction image by making reference to syntax information obtained from the received bitstream; adding the generated prediction image to a residual image obtained by dequantizing and inverse-transforming the bitstream, so as to obtain a decoded image; and reconstructing the decoded image into a 360-degree image according to a projection format. Therefore, the performance of image data compression can be improved.

Devices, systems and methods for sub-block based prediction are described. In a representative aspect, a method for video processing includes determining a block size constrain, making a determination, based on the block size constrain, about whether or not a merge affine mode and a non-merge affine mode are allowed for a video block in a video frame, and generating a bitstream representation of the video block based on the making the determination.

A method, apparatus and computer program products are provided for capturing omnidirectional video with one or more cameras, streaming the video over a network, and rendering the video on a Head Mounted Display (HMD) and more specifically to a method, apparatus, and computer program product for improving the visual quality of viewport-based omnidirectional video streaming. One example method includes selecting a primary viewport, encoding a first representation that covers the primary viewport, and encoding a second representation that provides a gradual picture quality change from a background viewport to the primary viewport.

The present invention relates to an image encoding and decoding technique for a high-definition video compression method and device for an omnidirectional security camera, and more specifically, to a method and a device whereby a differential motion vector is effectively transmitted, and an actual motion vector is calculated using the transmitted differential motion vector, and thus motion compensation is performed.

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.

As may be implemented with one or more embodiments, a video stream is divided into a key frame and subsequent chunks of frames including a key frame and Delta (D.sup.x) frames constructed from adjacent frames by dividing the frame into Motion Regions representing groups of pixels, determining a pixel group in an Earlier and later frame that is a best match for a pixel group in a Motion Region of a Current frame, and determining motion vectors for best matches for the Motion Regions and/or by intra-frame compression. A bitstream may be built such that as x increases, motion vector and other data relating to a combination of D.sup.x frames is represented by data that is less than all the data in the combination of D.sup.x frames and increases at a lower rate than the quantity of frames in D.sup.x compared to the quantity of frames in D.sup.x 1.

A method of decoding an image, includes obtaining at least one offset for a picture, deriving a variable for scaling for the picture based on the at least one offset, and performing inter prediction based on the variable for scaling for the picture. The at least one offset is defined with a direction of scaling.

The present invention relates to an image encoding and decoding technique for a high-definition video compression method and device for an omnidirectional security camera, and more specifically, to a method and a device whereby a differential motion vector is effectively transmitted, and an actual motion vector is calculated using the transmitted differential motion vector, and thus motion compensation is performed.