Non-binary occupancy maps for video-based point cloud coding

Abstract

A method and apparatus for encoding a video stream encoded using video point cloud coding includes the steps of obtaining a source point cloud; generating an occupancy map based on the source point cloud, the occupancy map including one or more pixels, wherein an occupancy value associated with each pixel is a non-binary value; encoding the occupancy map to generate an encoded occupancy map, wherein a block of the encoded occupancy map corresponds to one or more pixels of the occupancy map; selecting an occupancy value for the block based on the one or more pixels; and generating an encoded video stream based on the selected occupancy value.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 197,274, filed June 4, 2021, and U.S. Patent Application No. 17 / 496,270, filed October 7, 2021, the disclosures of which are incorporated by reference in their entireties herein.

[0002] This disclosure relates to a set of advanced video coding techniques, and more specifically, to video-based point cloud compression involving non-binary occupancy map representations. [Background technology]

[0003] Advanced three-dimensional (3D) world representations are enabling more immersive forms of interaction and communication. They are also enabling machines to understand, interpret, and navigate the world we live in. Point clouds are widely used as 3D representations of the world. For example, they can be used in autonomous vehicles for object detection and localization, in geographic information systems (GIS) for mapping, and in cultural traditions for visualizing and archiving cultural objects and collections. Several use cases related to point cloud data have been identified, and several corresponding requirements for point cloud representation and compression have been developed.

[0004] Point clouds include a set of high-dimensional (e.g., three-dimensional) points, each containing 3D location information and additional attributes such as color, reflectance, etc. These point clouds can be captured using multiple cameras and depth sensors, or lidar, in various configurations, and may consist of thousands up to billions of points to realistically represent the original scene.

[0005] Compression techniques are needed to reduce the amount of data needed to represent a point cloud, either for faster data transmission or reduced storage. ISO / IEC MPEG (JTC 1 / SC 29 / WG 11) has created an ad-hoc group (MPEG-PCC) to standardize compression techniques for static or dynamic clouds. Summary of the Invention [Means for solving the problem]

[0006] In an embodiment, a method for encoding an encoded video stream using video point cloud coding is executed by at least one processor and includes the steps of obtaining a source point cloud; generating an occupancy map comprising one or more pixels based on the source point cloud, where an occupancy value associated with each pixel is a non-binary value; encoding the occupancy map to generate an encoded occupancy map, where a block of the encoded occupancy map corresponds to one or more pixels of the occupancy map; selecting an occupancy value for the block based on the one or more pixels; and generating an encoded video stream based on the selected occupancy value.

[0007] In an embodiment, an apparatus for encoding a video stream using video point cloud coding comprises at least one memory configured to store program code; and at least one processor configured to read the program code and operate as instructed by the program code, the program code including: a first acquisition code configured to cause the at least one processor to acquire a source point cloud; a first generation code configured to cause the at least one processor to generate an occupancy map comprising one or more pixels based on the source point cloud, where an occupancy value associated with each pixel is a non-binary value; an encoding code configured to cause the at least one processor to encode the occupancy map to generate an encoded occupancy map, where a block of the encoded occupancy map corresponds to one or more pixels of the occupancy map; a selection code configured to cause the at least one processor to select an occupancy value for the block based on the one or more pixels; and a second generation code configured to cause the at least one processor to generate an encoded video stream based on the selected occupancy value.

[0008] In an embodiment, a non-transitory computer-readable medium storing computer instructions that, when executed by at least one processor, encode a video stream using video point cloud coding to cause the at least one processor to obtain a source point cloud, generate an occupancy map based on the source point cloud including one or more pixels, where an occupancy value associated with each pixel is a non-binary value, encode the occupancy map to generate an encoded occupancy map, where a block of the encoded occupancy map corresponds to one or more pixels of the occupancy map, select an occupancy value for the block based on the one or more pixels, and generate an encoded video stream based on the selected occupancy value.

[0009] Further features, nature and various advantages of the subject matter of the present disclosure will become more apparent from the following detailed description and the accompanying drawings. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic diagram of a simplified block diagram of a communication system according to one embodiment. [Diagram 2] FIG. 1 is a schematic diagram of a simplified block diagram of a streaming system according to one embodiment. [Diagram 3] FIG. 2 is a schematic diagram of a simplified block diagram of a video encoder according to one embodiment. [Figure 4] FIG. 2 is a schematic diagram of a simplified block diagram of a video decoder according to one embodiment. [Diagram 5] FIG. 2 illustrates an example of a B×B partially occupied block, according to one embodiment. [Figure 6] FIG. 2 illustrates an example of a 16-bit occupancy representation of a 4×4 block according to one embodiment. [Figure 7] FIG. 2 illustrates an example of an 8-bit occupancy representation of a 4×4 block according to one embodiment. [Figure 8] FIG. 2 illustrates an example of a 4-bit occupancy representation of a 4×4 block according to one embodiment. [Figure 9] 1 is a flow diagram illustrating a process performed by one embodiment. [Figure 10] FIG. 1 illustrates an apparatus according to one embodiment. [Figure 11] FIG. 1 illustrates a computer system suitable for implementing embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The consideration behind video-based point cloud compression (V-PCC) is to leverage existing video codecs to compress the shape, occupancy, and texture of a dynamic point cloud as three separate video sequences. The extra metadata required for the interpretation of the three video sequences may be compressed separately. A small portion of the overall bitstream is the metadata, which can be efficiently encoded / decoded using software implementations. A large amount of information can be handled by the video codec.

[0012] Embodiments of the present disclosure relate to annealing iterative shape smoothing to avoid over-smoothing in an iterative smoothing framework.Embodiments of the present disclosure relate to deriving reference points using a combination of mean and median statistics with the goal of reducing the computational complexity of using pure medians.

[0013] 1 to 4, an embodiment of the present disclosure is described for implementing the encoding and decoding structure of the present disclosure. The encoding and decoding structure of the present disclosure may implement the above-mentioned V-PCC aspect.

[0014] 1 illustrates a simplified block diagram of a communication system 100 according to one embodiment of the present disclosure. The system 100 may include at least two terminals 110, 120 interconnected via a network 150. In the case of unidirectional transmission of data, the first terminal 110 may code video data at a local location for transmission to the other terminal 120 via the network 150. The second terminal 120 may receive the coded video data of the other terminal from the network 150, decode the coded data, and display the recovered video data. Unidirectional data transmission may be common in media serving applications, etc.

[0015] 1 shows a second pair of terminals 130, 140 provided to support bidirectional transmission of coded video, such as may occur during a video conference. For bidirectional transmission of data, each terminal 130, 140 may code video data captured at a local location for transmission to the other terminal over network 150. Each terminal 130, 140 may also receive coded video data transmitted by the other terminal, decode the coded data, and display the recovered video data on a local display device.

[0016] In FIG. 1, terminals 110-140 may be, for example, servers, personal computers, and smartphones, and / or any other type of terminal. For example, terminals (110-140) may be laptop computers, tablet computers, media players, and / or dedicated video conferencing equipment. Network 150 represents any number of networks that convey coded video data between terminals 110-140, including, for example, wired and / or wireless communication networks. Communication network 150 may exchange data over circuit-switched and / or packet-switched channels. Representative networks include telecommunications networks, local area networks, wide area networks, and / or the Internet. For purposes of this discussion, the architecture and topology of network 150 may not be important to the operation of the present disclosure unless described herein below.

[0017] 2 shows an arrangement of video encoders and decoders in a streaming environment as an example of an application of the disclosed subject matter. The disclosed subject matter may be used in other video-enabled applications including, for example, video conferencing, digital TV, storage of compressed video on digital media including CDs, DVDs, memory sticks, etc.

[0018] 2, the streaming system 200 may include a capture subsystem 213 including a video source 201 and an encoder 203. The streaming system 200 may further include at least one streaming server 205 and / or at least one streaming client 206.

[0019] The video source 201 may generate a stream 202 including a 3D point cloud corresponding to a 3D video, for example. The video source 201 may include, for example, a 3D sensor (e.g., a depth sensor) or a 3D imaging technique (e.g., a digital camera) and a computing device configured to generate a 3D point cloud using data received from the 3D sensor or the 3D imaging technique. The sample stream 202, which may have a large data volume compared to an encoded video bitstream, may be processed by an encoder 203 coupled to the video source 201. As described in more detail below, the encoder 203 may include hardware, software, or a combination thereof to enable or implement aspects of the disclosed subject matter. The encoder 203 may further generate an encoded video bitstream 204. The encoded video bitstream 204, which may have a small data volume compared to the uncompressed stream 202, may be stored in a streaming server 205 for later use. One or more streaming clients 206 may access the streaming server 205 to obtain a video bitstream 209, which may be a copy of the encoded video bitstream 204.

[0020] The streaming client 206 can include a video decoder 210 and a display 212. The video decoder 210 can decode a video bitstream 209, which is, for example, an incoming copy of the encoded video bitstream 204, and generate an outgoing video sample stream 211 that can be rendered on a display 212 or another rendering device (not shown). In some streaming systems, the video bitstreams 204, 209 can be encoded according to some video coding / compression standards. Examples of such standards include, but are not limited to, ITU-T Recommendation H.265, Versatile Video Coding (VVC), and MPEG / V-PCC.

[0021] Several aspects of a V-PCC that may be performed by embodiments of the present disclosure are described below with reference to FIGS.

[0022] FIG. 3 is an exemplary functional block diagram of a video encoder 203 according to an embodiment of the present disclosure.

[0023] 3, the video encoder 203 may receive a point cloud frame 350 and generate a shape image 352, a texture image 356, and an occupancy map 334 based on the point cloud frame 350. The video encoder 203 may compress the shape image 352 into a compressed shape image 362, compress the texture image 356 into a compressed texture image 364, and compress the occupancy map 334 into a compressed occupancy map 372. The multiplexer 328 of the video encoder 203 may form a compressed bitstream 374 including the compressed shape image 362, the compressed texture image 364, and the compressed occupancy map 372.

[0024] More specifically, in an embodiment, the video encoder 203 may include a patch generation module 302 that divides the point cloud frame 350 into patches. A patch is a useful entity of the V-PCC. The patch generation process includes decomposing the point cloud frame 350 into a minimum number of patches with smooth boundaries, while further including minimizing the reconstruction error. The encoder of this disclosure may implement various methods to produce such a decomposition.

[0025] The video encoder 203 may include a patch packing module 304 that performs a packing process. The process of packing involves mapping the extracted patches to a 2D grid while minimizing unused space, and ensuring that every M×M (e.g., 16×16) block of the grid is associated with a unique patch. Efficient patch packing has a direct impact on compression efficiency by minimizing unused space or by ensuring temporal consistency. The patch packing module 304 may generate an occupancy map 334.

[0026] The video encoder 203 may include a shape image generation module 306 and a texture image generation module 308. To handle cases where multiple points are projected onto the same sample, each patch may be projected onto two images called layers. For example, the shape image generation module 306 and the texture image generation module 308 may use the 3D to 2D mapping calculated during the packing process of the patch packing module 304 to store the shape and texture of the point cloud as images (also called layers). The generated images / layers may be stored as video frames and compressed using a video codec (e.g., HM video codec) according to the configuration provided as a parameter.

[0027] In an embodiment, based on the input point cloud frame 350 and the occupancy map 334, the shape image generation module 306 forms a shape image 352 and the texture image generation module 308 generates a texture image 356. In one embodiment, the shape image 352 may be represented in YUV420-8 bit format as a monochromatic frame of WxH. In one embodiment, the occupancy map 334 image may be represented as a binary map indicating whether each cell of the grid belongs to the space or to the point cloud, and the texture image generation module 308 may use the reconstructed / smoothed shape 358 to calculate the color associated with the resampled points to generate the texture image 356.

[0028] The video encoder 203 may further include an image padding module 314 that pads the shape image 352 and an image padding module 316 that pads the texture image 356 to form a padded shape image 354 and a padded texture image 360. Image padding (also called background filling) simply fills the unused space of an image with redundant information. A good background fill is one that minimizes the bitrate increase while not introducing significant coding artifacts around the patch boundaries. The image padding module 314 and the image padding module 316 may use the occupancy map 334 to form the padded shape image 354 and the padded texture image 360, respectively. In one embodiment, the video encoder 203 may include a group expansion module 320 to form the padded texture image 360.

[0029] The video encoder 203 may include a video compression module 322 that compresses the padded shape image 354 into a compressed shape image 362, and a video compression module 324 that compresses the padded texture image 360 ​​into a compressed texture image 364.

[0030] The video encoder 203 may include an entropy compression module 318 for lossless encoding 366 of the occupancy map 334 and a video compression module 326 for lossy encoding 368 of the occupancy map 334 .

[0031] In an embodiment, the video encoder 203 may include a smoothing module 310 that uses the reconstructed shape image 365 provided by the video compression module 322 and the patch information 332 to generate a smoothed shape 358. The smoothing procedure of the smoothing module 310 may aim to mitigate potential discontinuities that may occur at patch boundaries due to compression artifacts. The smoothed shape 358 may be used by the texture image generation module 308 to generate a texture image 356.

[0032] The video encoder 203 may further include an auxiliary patch information compression module 312 that forms compressed auxiliary patch information 370, which is provided as a compressed bitstream 374 by the multiplexer 328.

[0033] FIG. 4 is an example functional block diagram of a video decoder 210, according to an embodiment of the present disclosure.

[0034] As shown in FIG. 4, the video decoder 210 receives the coded bitstream 374 from the video encoder 203 and converts it into a compressed shape Image 362, compressed Texture The video decoder 210 may obtain the image 364, the compressed occupancy map 372, and the compressed auxiliary patch information 370. shape Image 362, compressed TextureThe image 364, the compressed occupancy map 372, and the compressed auxiliary patch information 370 may be decoded to obtain a reconstructed texture image 460, a reconstructed shape image 462, a reconstructed occupancy map 464, and a reconstructed auxiliary patch information 466, respectively. The video decoder 210 may then generate a reconstructed point cloud 474 based on the reconstructed texture image 460, the reconstructed shape image 462, the reconstructed occupancy map 464, and the reconstructed auxiliary patch information 466.

[0035] In an embodiment, the video decoder 210 extracts the compressed shape Image 362, compressed Texture It may also include a demultiplexer 402 that distributes the image 364 , the compressed occupancy map 372 , and the compressed auxiliary patch information 370 .

[0036] The video decoder 210 shape A video decompression module 404 that decodes the image 362, Texture It may include a video decompression module 406 for decoding the image 364 , an occupancy map decompression module 408 for decoding the compressed occupancy map 372 , and an auxiliary patch information decompression module 410 for decoding the compressed auxiliary patch information 370 .

[0037] The video decoder 210 may include a shape reconstruction module 412 that obtains a reconstructed (three-dimensional) shape 468 based on a reconstructed shape image 462, a reconstructed occupancy map 464, and a reconstructed auxiliary patch information 466.

[0038] The video decoder 210 may include a smoothing module 414 that smooths the reconstructed shape 468 to obtain a smoothed shape 470. The smoothing procedure may aim to mitigate potential discontinuities that may occur at patch boundaries due to compression artifacts.

[0039] The video decoder 210 may include a texture reconstruction module 416 that obtains a reconstructed texture 472 based on the restored texture image 460 and the smoothed shape 470.

[0040] The video decoder 210 may include a color smoothing module 418 that smooths colors of the reconstructed texture 472 to obtain a reconstructed point cloud 474. Patches that are not adjacent in 3D space are often packed adjacent to each other in 2D video. This means that pixel values ​​of non-adjacent patches may be mixed by block-based video codecs. The color smoothing of the color smoothing module 418 may aim to reduce visible artifacts that appear at patch boundaries. Occupancy Maps in Video-Based Point Cloud Compression (V-PCC)

[0041] In the MPEG PCC Test Model Category 2 (TMC2) model, which may correspond to V-PCC, the occupancy map may be a binary image, where each binary pixel in the image indicates whether or not there is at least one 3D point projected onto it.

[0042] The occupancy map can be encoded with a precision of B × B blocks, where B is a user-defined parameter. To achieve lossless encoding, B0 must be set to 1. In practice, B=2 or B=4 yield visually acceptable results while significantly reducing the number of bits required to encode the occupancy map.

[0043] If an occupancy map block is occupied, all points in the block are reconstructed during the decoding process, even if they are only partially occupied, and the occupancy precision is equal to 4, the number of reconstructed points per block is 16. In the most extreme case, a single occupied position is sufficient to mark the corresponding occupancy map block. As a result, during the decoding process, 16 points are generated instead of just one (assuming the occupancy precision is equal to 4).

[0044] In V-PCC, the occupancy map is constrained to be binary, which can cause shape distortions when the occupancy precision B is greater than 1. For example, in Fig. 5, if B=4, the block is partially occupied by pixels marked as "X". However, all 16 pixels in the reconstructed occupancy map are occupied.

[0045] The embodiments disclosed herein may be used separately or combined in any order. Furthermore, each embodiment, e.g., the encoder and decoder, may be implemented by a processing circuit (e.g., one or more processors or one or more integrated circuits). In one example, the one or more processors execute a program stored in a non-transitory computer-readable medium.

[0046] In an embodiment, the occupancy map may be non-binary, i.e. its pixel values ​​may be greater than 1. For example, if the occupancy map is represented in 8 bits, its values ​​may be 0, 1, 2, ..., 255.

[0047] Every value in the non-binary occupancy map can represent a particular pattern of occupancy states of the corresponding B×B block. The bit depth of the occupancy map can be signaled in the high-level syntax of the bitstream. The mapping strategy of the non-binary occupancy values ​​to the occupancy states can also be signaled in the high-level syntax of the bitstream.

[0048] In one embodiment, B=4, and 16 bits can be used to represent all combinations of the occupancy patterns of a 4×4 block. As an example, the most significant bit (MSB) of 16 bits can be used to represent the occupancy status of the top-left pixel in the block, the least significant bit (LSB) of 16 bits can be used to represent the occupancy status of the bottom-right pixel in the block, and the bits between the MSB and LSB can be used to represent the occupancy status of the remaining pixels in raster scan order. As shown in FIG. 6, some examples of 16-bit occupancy representations and corresponding patterns are visualized. However, in the embodiment, any mapping strategy can be used.

[0049] In another embodiment, B=4, and only 8 bits can represent the occupation pattern of a 4×4 block. This is therefore a representation of a subset of all occupation patterns. For example, each bit can be used to represent the occupation state of every two pixels. For example, if a bit is equal to 1, this can indicate that the two pixels corresponding to the bit are both occupied. Otherwise, the two pixels are both empty. An example is shown in FIG. 7. However, any mapping strategy can be used in the embodiment.

[0050] In another embodiment, B=4, and only 4 bits can represent the occupation pattern of a 4×4 block. This is therefore a representation of a subset of all occupation patterns. For example, each bit can be used to represent the occupation state of every fourth pixel. For example, if the bit is equal to 1, this can indicate that all four pixels are occupied. Otherwise, all four pixels are empty. An example is shown in FIG. 8. However, any mapping strategy can be used in the embodiment.

[0051] In an embodiment, the non-binary occupancy map may be coded by lossy or lossless coding.

[0052] Figure 9 shows ,direction9 is a flowchart of method 900. In some implementations, one or more process blocks of FIG. 9 may be performed by encoder 203. In some implementations, one or more process blocks of FIG. 9 may be performed by another device or group of devices that is separate from or includes encoder 203, such as decoder 210.

[0053] As shown in FIG. 9, in operation 910, the method 900 may include obtaining a source point cloud.

[0054] At operation 920, the method 900 may include generating an occupancy map based on the source point cloud, the occupancy map including one or more pixels. In an embodiment, the occupancy value associated with each pixel may be a non-binary value.

[0055] In operation 930, the method 900 may include encoding the occupancy map to generate an encoded occupancy map, where a block of the encoded occupancy map corresponds to one or more pixels of the occupancy map.

[0056] In operation 940, the method 900 may include selecting an occupancy value for the block based on the one or more pixels.

[0057] At operation 950, the method 900 may include generating an encoded video stream based on the selected occupancy values.

[0058] In an embodiment, the number of the one or more pixels may be 16 and the occupancy value may be a 16-bit value.

[0059] In an embodiment, each bit of the 16-bit value may be used to signal a corresponding pixel occupancy of one or more pixels.

[0060] In an embodiment, the most significant bit of the occupancy value may be used to signal the occupancy of a top-left pixel of one or more pixels, the least significant bit of the occupancy value may be used to signal the occupancy of a bottom-right pixel of one or more pixels, and the remaining bits of the occupancy value may be used to signal the remaining pixels of the one or more pixels in raster scan order.

[0061] In an embodiment, the number of the one or more pixels may be 16 and the occupancy value may be an 8-bit value.

[0062] In an embodiment, each bit of an 8-bit value may be used to signal the occupancy of two corresponding pixels of one or more pixels.

[0063] In an embodiment, the number of the one or more pixels may be 16 and the occupancy value may be a 4-bit value.

[0064] In an embodiment, each bit of the 4-bit value may be used to signal the occupancy of four corresponding pixels of one or more pixels.

[0065] In an embodiment, the encoded occupancy map may be encoded using lossy or lossless coding.

[0066] Although Figure 9 illustrates example blocks of method 900, in some implementations, method 900 may include additional, fewer, different, or differently arranged blocks than those illustrated in Figure 9. Additionally or alternatively, two or more of the blocks of method 900 may be performed in parallel.

[0067] 10 is a diagram of an apparatus 1000 for encoding a video stream using video point cloud coding according to an embodiment. As shown in FIG. 10, the apparatus 800 comprises a first acquisition code 1010, a first generation code 1020, an encoding code 1030, a selection code 1040, and a second generation code 1050.

[0068] The first acquisition code 1010 may be configured to cause at least one processor to acquire a source point cloud.

[0069] The first generation code 1020 may be configured to cause the at least one processor to generate an occupancy map including one or more pixels based on the source point cloud. In an embodiment, an occupancy value associated with each pixel may be a non-binary value.

[0070] The encoding code 1030 may be configured to cause at least one processor to encode the occupancy map to generate an encoded occupancy map, where a block of the encoded occupancy map corresponds to one or more pixels of the occupancy map.

[0071] The selection code 1040 may be configured to cause the at least one processor to select an occupancy value for the block based on one or more pixels.

[0072] The second generating code 1050 may be configured to cause the at least one processor to generate an encoded video stream based on the selected occupancy value.

[0073] The techniques described above may be implemented using computer readable instructions and as computer software physically stored on one or more computer readable media. For example, FIG. 11 illustrates a computer system 1100 suitable for implementing certain embodiments of the present disclosure.

[0074] The computer software may be coded using any suitable machine code or computer language that may be subjected to mechanisms such as assembly, compilation, linking, etc. to produce code containing instructions that can be executed by a computer central processing unit (CPU), graphics processing unit (GPU), etc. directly, or via interpretation, microcode execution, etc.

[0075] The instructions may be executed on various types of computers or components thereof, including, for example, personal computers, tablet computers, servers, smartphones, gaming devices, Internet of Things devices, and the like.

[0076] 11 for computer system 1100 are examples and are not intended to suggest any limitation as to the scope of use or functionality of the computer software implementing embodiments of the present disclosure. The arrangement of components should not be interpreted as having a dependency or requirement regarding any one or combination of components illustrated in the non-limiting embodiment of computer system 1100.

[0077] The computer system 1100 may include certain human interface input devices. Such human interface input devices may respond to input by one or more human users, for example, via tactile input (such as keystrokes, swipes, data glove movements), audio input (such as voice, clapping), visual input (such as gestures), or olfactory input (not depicted). Human interface devices may also be used to capture certain media not necessarily directly associated with conscious human input, such as audio (such as voice, music, ambient sounds), images (such as scanned images, photographic images obtained from still image cameras), and video (such as two-dimensional video, three-dimensional video including stereoscopic video, etc.).

[0078] The input human interface devices may include one or more of a keyboard 1101, a mouse 1102, a trackpad 1103, a touch screen 1110, a data glove, a joystick 1105, a microphone 1106, a scanner 1107, a camera 1108 (only one of each is shown).

[0079] The computer system 1100 may also include certain human interface output devices. Such human interface output devices may stimulate one or more human user senses, for example, through haptic output, sound, light, and smell / taste. Such human interface output devices may include haptic output devices (e.g., haptic feedback via touch screen 1110, data gloves, or joystick 1105, although there may also be haptic feedback devices that do not function as input devices). For example, such devices may be audio output devices (such as speakers 1109, headphones (not depicted)), visual output devices (such as screens 1110, including CRT screens, LCD screens, plasma screens, OLED screens, each with or without touch screen input capabilities, each with or without haptic feedback capabilities, some of which may be capable of outputting two-dimensional visual output or three-dimensional or higher output via means such as stereographic output, virtual reality glasses (not depicted), holographic displays, and smoke tanks (not depicted)), and printers (not depicted).

[0080] The computer system 1100 may also include human accessible storage devices and their associated media, such as optical media including CD / DVD ROM / RW 1120 having media 1121 such as CDs / DVDs, thumb drives 1122, removable hard drives or solid state drives 1123, legacy magnetic media such as tapes and floppy disks (not shown), dedicated ROM / ASIC / PLD based devices such as security dongles (not shown).

[0081] Those skilled in the art should also understand that the term "computer-readable medium" as used in connection with the presently disclosed subject matter does not encompass transmission media, carrier waves, or other transitory signals.

[0082] The computer system 1100 may also include interfaces to one or more communication networks. The networks may be, for example, wireless, wired, optical. The networks may further be local, wide area, metropolitan, vehicular and industrial, real-time, delay tolerant, etc. Examples of networks include local area networks such as Ethernet, wireless LAN, cellular networks including GSM, 3G, 4G, 5G, LTE, etc., TV wired or wireless wide area digital networks including cable TV, satellite TV, and terrestrial broadcast TV, vehicular and industrial including CANBus, etc. Certain networks generally require an external network interface adapter connected to a particular general-purpose data port or peripheral bus 1149 (e.g., a USB port on the computer system 1100, etc.), while others are generally integrated into the core of the computer system 1100 by connecting to a system bus as described below (e.g., an Ethernet interface to a PC computer system or a cellular network interface to a smartphone computer system). Using any of these networks, the computer system 1100 may communicate with other entities. Such communications may be one-way receive only (e.g., broadcast TV), one-way transmit only (e.g., CANbus to a particular CANbus device), or two-way with other computer systems using, for example, local or wide area digital networks. Such communications may include communications to a cloud computing environment 1155. Particular protocols and protocol stacks may be used in each of those networks and network interfaces, as described above.

[0083] The aforementioned human interface devices, human accessible storage, and network interface 1154 may be attached to the core 1140 of the computer system 1100 .

[0084] The core 1140 may include specialized programmable processing devices in the form of one or more central processing units (CPUs) 1141, graphics processing units (GPUs) 1142, field programmable gate areas (FPGAs) 1143, hardware accelerators for certain tasks 1144, etc. These devices may be connected via a system bus 1148 along with read only memory (ROM) 1145, random access memory 1146, internal mass storage devices 1147 such as internal hard drives, SSDs, etc. that are not accessible to the user. In some computer systems, the system bus 1148 may be accessible in the form of one or more physical plugs to allow expansion with additional CPUs, GPUs, etc. Peripheral devices may be attached directly to the core's system bus 1148 or via a peripheral bus 1149. Peripheral bus architectures include PCI, USB, etc. A graphics adapter 1150 may be included in the core 1140.

[0085] The CPU 1141, GPU 1142, FPGA 1143, and accelerator 1144 can execute certain instructions that, in combination, can constitute the aforementioned computer code. The computer code can be stored in ROM 1145 or RAM 1146. Temporary data can be stored in RAM 1146 as well, while persistent data can be stored in, for example, internal mass storage device 1147. The use of cache memory allows for quick storage and retrieval in any memory device, which can be closely associated with one or more of the CPU 1141, GPU 1142, mass storage device 1147, ROM 1145, RAM 1146, etc.

[0086] The computer-readable medium can bear computer code for performing various computer-implemented operations. The medium and computer code may be those specially designed and constructed for the purposes of the present disclosure, or they may be of the available kind well known to those skilled in the computer software arts.

[0087] By way of example and not limitation, a computer system having the architecture 1100, and in particular the core 1140, can provide functionality as a result of one or more processors (including CPUs, GPUs, FPGAs, accelerators, etc.) executing software embodied in one or more tangible computer-readable media. Such computer-readable media can be the user-accessible mass storage devices introduced above, as well as media associated with specific storage devices of the core 1140 that are non-transitory in nature, such as the core internal mass storage device 1147 and the ROM 1145. Software implementing various embodiments of the present disclosure can be stored in such devices and executed by the core 1140. The computer-readable media can include one or more memory devices or chips, depending on the particular needs. The software can cause the core 1140, and in particular the processors therein (including CPUs, GPUs, FPGAs, etc.) to perform certain processes or certain portions of certain processes described herein, including the definition of data structures stored in the RAM 1146 and modifying such data structures according to the software-defined processes. Additionally or alternatively, the computer system may provide functionality as a result of logic hardwired or otherwise embedded in circuitry (e.g., accelerator 1144) that may operate in place of or together with software to perform particular processes or particular portions of particular processes described herein. Where appropriate, references to software may encompass logic and vice versa. Where appropriate, references to computer-readable media may encompass circuitry (such as an integrated circuit (IC)) that stores software for execution, circuitry that embodies logic for execution, or both. The present disclosure encompasses any suitable combination of hardware and software.

[0088] While this disclosure describes several non-limiting embodiments, there are modifications, permutations, and various substitute equivalents that are within the scope of this disclosure. Thus, it will be appreciated that those skilled in the art will be able to devise numerous systems and methods that, although not explicitly shown or described herein, embody the principles of the present disclosure and are therefore within its spirit and scope. [Explanation of symbols]

[0089] 100 Communication Systems 110 First Terminal 120 Second Terminal 130 terminals 140 terminals 150 Network 200 Streaming System 201 Video Sources 202 Stream 203 Video Encoder 204 Encoded Video Bitstream 205 Streaming Server 206 Streaming Client 209 Video Bitstream 210 Video Decoder 211 outgoing video sample stream 212 Display 213 Capture Subsystem 302 Patch Generation Module 304 Patch Packing Module 306 Shape Image Generation Module 308 Texture Image Generation Module 310 Smoothing Module 312 Auxiliary patch information compression module 314 Image Padding Module 316 Image Padding Module 318 Entropy Compression Module 320 Group Expansion Module 322 Video Compression Module 324 Video Compression Module 326 Video Compression Module 328 Multiplexer 332 Patch Information 334 Occupied Map 350 point cloud frames 352 Shape Images 354 padded shape images 356 Texture Images 358 Reconstructed / Smoothed Shape 360 padded texture images 362 Compressed Shape Images 364 Compressed Texture Image 365 Reconstructed Shape Images 366 lossless encoding 368 Lossy Encoding 370 Compressed Supplemental Patch Information 372 Compressed Occupancy Map 374 Compressed Bitstream 402 Demultiplexer 404 Video Recovery Module 406 Video Recovery Module 408 Occupancy Map Restoration Module 410 Auxiliary patch information restoration module 412 Shape Reconstruction Module 414 Smoothing Module 416 Texture Reconstruction Module 418 Color Smoothing Module 460 Recovered Texture Images 462 Reconstructed Shape Images 464 Reconstructed Occupancy Map 466 Restored auxiliary patch information 468 Reconstructed Shape 470 Smoothed Shape 472 Reconstructed Textures 474 Reconstructed Point Cloud 800 equipment 900 ways 1000 devices 1010 First acquisition code 1020 First generated code 1030 encoding code 1040 Selection Code 1050 Second generated code 1100 Computer Systems 1101 Keyboard 1102 Mouse 1103 Trackpad 1105 Joystick 1106 Microphone 1107 Scanner 1108 Camera 1109 Speaker 1110 Touch Screen 1121 Medium 1122 Thumb Drive 1123 Solid State Drive 1140 cores 1143 Field Programmable Gate Area (FPGA) 1144 Hardware Accelerator 1145 Read-Only Memory (ROM) 1146 Random Access Memory 1147 Mass storage 1148 System Bus 1149 Surrounding bus 1150 Graphics Adapter 1154 Network Interface 1155 Cloud Computing Environment

Claims

1. 1. A method for encoding a video stream encoded using video point cloud coding, the method being executed by at least one processor and comprising: obtaining a source point cloud; generating an occupancy map based on the source point cloud, the occupancy map comprising a plurality of pixels; encoding the occupancy map to generate an encoded occupancy map, a block of the encoded occupancy map corresponding to a number of pixels of the occupancy map; selecting an occupancy value for the block based on the plurality of pixels, the occupancy value being a non-binary value, each bit of the occupancy value representing an occupancy pattern of the block of two or more corresponding subsets of the plurality of pixels, the number of pixels being 16, and each bit of the non-binary value corresponding to an occupancy state of a non-square subset of two pixels; generating an encoded video stream based on the selected occupancy values.

2. the most significant bit of the occupancy value is used to signal the occupancy of a top left pixel of the plurality of pixels; the least significant bit of the occupancy value is used to signal the occupancy of a bottom right pixel of the plurality of pixels; The method of claim 1 , wherein remaining bits of the occupancy value are used to signal remaining pixels of the plurality of pixels in raster scan order.

3. The method of claim 1 , wherein the encoded occupancy map is encoded using lossy coding.

4. Apparatus configured to perform the method according to any one of claims 1 to 3.

5. A computer program for encoding a video stream using video point cloud coding, which, when executed by at least one processor, causes the at least one processor to perform the method of any one of claims 1 to 3.

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