A method for encoding a video sequence in a scalable video encoder to generate a scalable bitstream is provided that includes encoding the video sequence in a first layer encoder of the scalable video encoder to generate a first sub-bitstream, encoding the video sequence in a second layer encoder of the scalable video encoder to generate a second sub-bitstream, wherein portions of the video sequence being encoded in the second layer encoder are predicted using reference portions of the video sequence encoded in the first layer encoder, combining the first sub-bitstream and the second sub-bitstream to generate the scalable bitstream, and signaling in the scalable bitstream an indication of a maximum decoded picture buffer (DPB) size needed for decoding the second sub-bitstream and the first sub-bitstream when the second sub-bitstream is a target sub-bitstream for decoding.

An original input content is subjected to multiple constant quality probe encodes for a defined set of resolutions. In one embodiment, probe encodes encode a few parts of the original source video, for example, 30 seconds from 5 different positions. Each probe encode delivers an average bitrate that is required to achieve the configured constant quality. The mean value of the average bitrate is taken per resolution. This results in a list of bitrates that map to a resolution that would achieve the best quality, a custom bitrate table. Based on the custom bitrate table, an optimized bitrate ladder is computed. The process starts with a configurable minimum bitrate and steps up by a bitrate step size that is between a configurable min and max bitrate step size until the bitrate of the highest resolution is reached.

An original input content is subjected to multiple constant quality probe encodes for a defined set of resolutions. In one embodiment, probe encodes encode a few parts of the original source video, for example, 30 seconds from 5 different positions. Each probe encode delivers an average bitrate that is required to achieve the configured constant quality. The mean value of the average bitrate is taken per resolution. This results in a list of bitrates that map to a resolution that would achieve the best quality, a custom bitrate table. Based on the custom bitrate table, an optimized bitrate ladder is computed. The process starts with a configurable minimum bitrate and steps up by a bitrate step size that is between a configurable min and max bitrate step size until the bitrate of the highest resolution is reached.

File format concepts for video files are described. It is proposed to that descriptive data of a file indicates whether a parameter set for a track of a file is forwarded when jointly decoding a sub-stream of the track and a further track, and/or that a file includes, for a sub-stream of a video stream signaled in the file, an alternative parameter set to a parameter set for fully decoding the track, the alternative parameter set being for decoding the sub-stream, so as to allow for switching between multiple tracks of a file, and/or that step-wise stream access pictures of a track of a file are marked as stream access point pictures for accessing the track, and/or that a temporal length within which a decoder refresh in case of a joint decoding of sub-streams distributed over multiple tracks is indicated in a file, and/or that a file provides information from which it is derivable whether a pixel aspect ratio varies.

File format concepts for video files are described. It is proposed to that descriptive data of a file indicates whether a parameter set for a track of a file is forwarded when jointly decoding a sub-stream of the track and a further track, and/or that a file includes, for a sub-stream of a video stream signaled in the file, an alternative parameter set to a parameter set for fully decoding the track, the alternative parameter set being for decoding the sub-stream, so as to allow for switching between multiple tracks of a file, and/or that step-wise stream access pictures of a track of a file are marked as stream access point pictures for accessing the track, and/or that a temporal length within which a decoder refresh in case of a joint decoding of sub-streams distributed over multiple tracks is indicated in a file, and/or that a file provides information from which it is derivable whether a pixel aspect ratio varies.

A file encapsulation method and apparatus, a file transmission method and apparatus, a file decoding method and apparatus, an electronic device, and a storage medium. The file encapsulation method includes: obtaining an encoded target video and temporal layer information of samples determined during encoding of the target video, encapsulating the encoded target video according to the temporal layer information of the samples to generate a first encapsulated file, the first encapsulated file including the temporal layer information of the samples, and transmitting the first encapsulated file to a first device.

A file encapsulation method and apparatus, a file transmission method and apparatus, a file decoding method and apparatus, an electronic device, and a storage medium. The file encapsulation method includes: obtaining an encoded target video and temporal layer information of samples determined during encoding of the target video, encapsulating the encoded target video according to the temporal layer information of the samples to generate a first encapsulated file, the first encapsulated file including the temporal layer information of the samples, and transmitting the first encapsulated file to a first device.

A transmission device of point cloud data and method performed by the transmission device, and a reception device and a method performed by the reception device are provided. A method performed by a reception device of point cloud data comprises acquiring geometry-based point cloud compression(G-PCC) file including the point cloud data, wherein the G-PCC file includes information on a sample group in which samples in the G-PCC file are grouped based on one or more temporal levels and wherein the G-PCC file further includes information on the temporal levels, and extracting one or more samples belonging to a target temporal level from the samples in the G-PCC file based on the information on the sample group and the information on the temporal levels.

A transmission device of point cloud data and method performed by the transmission device, and a reception device and a method performed by the reception device are provided. A method performed by a reception device of point cloud data comprises acquiring geometry-based point cloud compression(G-PCC) file including the point cloud data, wherein the G-PCC file includes information on a sample group in which samples in the G-PCC file are grouped based on one or more temporal levels and wherein the G-PCC file further includes information on the temporal levels, and extracting one or more samples belonging to a target temporal level from the samples in the G-PCC file based on the information on the sample group and the information on the temporal levels.

An image encoding/decoding method and apparatus is provided. The image decoding method comprises determining whether first information specifying a value of a picture order count (POC) most significant bit (MSB) cycle of a current picture is present in a picture header, determining a POC MSB of the current picture based on whether the first information is present in the picture header, and deriving a POC of the current picture based on the determined POC MSB. Based on the first information being not present in the picture header and the current picture being not a CLVSS (coded layer video sequence start) picture, a POC difference between the current picture and a previous picture preceding the current picture in decoding order may be less than half a maximum value of a POC least significant bit (LSB) of the current picture.