This disclosure also teaches a system and method for scanning a specimen into a focus-stacked scan. In one embodiment, a method for scanning the specimen into a focus-stacked scan can comprise illuminating the specimen with a light. The specimen can comprise a topography. The depths of the topography can be variable along a z-axis. The method can also comprise dividing the specimen into a plurality of regions. Each of the regions can comprise a regional peak in the topography. Additionally, the method can comprise sampling each of the regions at a plurality of focal planes orthogonal to the z-axis by capturing, at each focal plane, an image of the region. The image can be focused on the focal plane. Lastly, the method can comprise focus-stacking, for each of the region the images within the region, into a focus-stacked image, and stitching together the focus-stacked images.

A method of encoding a video image includes, for each one of blocks of the video image, calculating virtual gradient values in the block depending on neighboring gradient values computed in a causal neighborhood of the block and acquiring one prediction direction or non-directional intra prediction mode based on the virtual gradient values; and determining a coding mode by comparing different predictions for the block, acquiring a predicted block by applying the determined “coding mode”, acquiring a residual error between the predicted block and the current block and encoding a difference between the determined coding mode and the prediction direction or non-directional intra prediction mode. The calculating includes, for each prediction direction, propagating the neighboring gradient values along the prediction direction to estimate the virtual gradient values in the block.

Embodiments of the present invention provide video signal processing methods. A video signal encoding method according to an embodiment of the present invention comprises checking a transform block including residual samples except a prediction sample from a picture of the video signal, generating transform coefficients through a transform for the residual samples of the transform block based on a size of the transform block, and performing quantization and entropy coding the transform coefficients, wherein generating the transform coefficients includes, applying a forward primary transform to each of a horizontal direction and vertical direction of the transform block including the residual samples, and not applying a forward non-separable secondary transform to the transform block to which the primary transform has been applied when the size of the transform block is smaller than or equal to 4×4, and applying the forward non-separable secondary transform to the transform block when the size of the transform block is greater than 4×4.

A method for intra prediction comprises determining a first MPM candidate corresponding to a left-side candidate block on the basis of a position of the left-side candidate block adjacent to a left side of a current block; determining a second MPM candidate corresponding to an upper-end candidate block on the basis of a position of the upper-end candidate block adjacent to an upper end of the current block; generating an MPM candidate list including a plurality of MPM candidates, on the basis of the first MPM candidate and the second MPM candidate; and determining one MPM candidate of the plurality of the MPM candidates that constitute the MPM candidate list as an intra prediction mode of the current block, and performing intra prediction for the current block on the basis of the determined intra prediction mode to generate a prediction block corresponding to the current block.

Method for coding or recognizing of surveillance videos is provided to improve compressing efficiency and recognizing accuracy of surveillance videos. The method for coding surveillance videos includes: establishing a background database and a foreground object database; wherein, the background database includes a set of background images; the foreground object database includes a set of foreground objects; coding a surveillance image by referring to a background image in the background database and a foreground object in the foreground object database.

An apparatus configured to code video information in a bitstream includes a memory and a processor in communication with the memory. The memory is configured to store video information associated with a video layer having a current picture. The processor is configured to: determine whether a slice segment header extension associated with the current picture is present in the bitstream; and determine that one or more most significant bits (MSBs) of a picture order count (POC) value associated with the current picture are not present in the bitstream in response to a determination that the slice segment header extension associated with the current picture is not present in the bitstream. The processor may encode or decode the video information in the bitstream.

An apparatus for coding video information according to certain aspects includes a memory unit and a processor in communication with the memory unit. The memory unit stores video information of a reference layer. The processor determines a value of a video unit based at least in part on a prediction value and an adjusted residual prediction value associated with the reference layer. The adjusted residual prediction value is equal to a residual prediction from the reference layer multiplied by a weighting factor that is different from 1.

A method for video processing is described. The method comprises: making a decision, for a conversion between a current video block of a video picture of a video and a coded representation of the video, regarding a size of a reference region of the video picture from which reference samples are used for predicting the current video block, based on a size of a virtual pipeline data unit (VPDU), a size of a coding tree block (CTB), or a size of a coding tree unit (CTU); and performing the conversion based on the decision.

An example apparatus includes a first frame buffer configured to store video data; a second frame buffer configured to store video data; and one or more processors configured to: reconstruct samples of a first block of a current picture of video data; store, in parallel, a compressed version of the samples of the first block of video data in the first frame buffer and an uncompressed version of the samples of the first block of video data in the second frame buffer; and responsive to determining to reconstruct a second block of the current picture of video data using intra block copy: obtain, from the second frame buffer, samples of a predictor block located in the current picture of video data, the predictor block at least partially overlapping the first block of video data; and predict, based on the obtained samples of the predictor block, samples of the second block.

An image decoding method according to the present document may include the steps of: deriving the position of the final significant coefficient in the current block and transform coefficients for the current block on the basis of residual information; determining whether the index of a sub-block including the final significant coefficient is 0 and whether the position of the final significant coefficient in the sub-block is greater than 0; determining whether a significant coefficient exists in a second area excluding a first area at the upper left end of the current block; and parsing an LFNST index from a bitstream when the position of the final significant coefficient is determined to be greater than 0 in the sub-block in which the index is 0, and the significant coefficient does not exist in the second area.