Abstract: Technologies are described herein for enhancing a user presence status determination. Visual data may be received from a depth camera configured to be arranged within a three-dimensional space. A current user presence status of a user in the three-dimensional space may be determined based on the visual data. A previous user presence status of the user may be transformed to the current user presence status, responsive to determining the current user presence status of the user.

Abstract: Technologies are described herein for enhancing a user presence status determination. Visual data may be received from a depth camera configured to be arranged within a three-dimensional space. A current user presence status of a user in the three-dimensional space may be determined based on the visual data. A previous user presence status of the user may be transformed to the current user presence status, responsive to determining the current user presence status of the user.

Abstract: Technologies are described herein for enhancing a user presence status determination. Visual data may be received from a depth camera configured to be arranged within a three-dimensional space. A current user presence status of a user in the three-dimensional space may be determined based on the visual data. A previous user presence status of the user may be transformed to the current user presence status, responsive to determining the current user presence status of the user.

Abstract: A state client is configured to allow a user to specify a meeting-specific state, such as that the user is running late for a meeting, checked in to the meeting, or unable to attend the meeting. A state service stores data identifying the user's meeting-specific state. The state service also responds to requests for the state of the user. In one implementation, when such a request is received, the state service determines whether the user is an invitee to the same meeting as the user requesting the state. If not, the state service returns a general-purpose state indicator for the user. If both users are invitees to the same meeting, the state service returns the meeting-specific state indicator, which may then be displayed by a state client.

Abstract: A video encoder identifies a current smooth region of a current picture in a sequence and performs temporal analysis by determining whether a corresponding region in at least one previous and/or future picture is smooth. Based at least in part on the temporal analysis, the encoder adjusts quantization in the current smooth region. An encoder determines a differential quantization interval for a sequence, the interval comprising an interval number. The interval constrains the encoder to skip differential quantization for at least the interval number of predicted pictures after a predicted differentially quantized picture. An encoder analyzes texture in a current picture and sets a smoothness threshold. The encoder compares texture data with the smoothness threshold and adjusts differential quantization for at least part of the current picture based on a finding of at least one smooth region in the current picture according to the smoothness threshold.

Abstract: Technologies are described herein for enhancing a user presence status determination. Visual data may be received from a depth camera configured to be arranged within a three-dimensional space. A current user presence status of a user in the three-dimensional space may be determined based on the visual data. A previous user presence status of the user may be transformed to the current user presence status, responsive to determining the current user presence status of the user.

Abstract: Quality settings established by an encoder are adjusted based on information associated with regions of interest (“ROIs”). For example, quantization step sizes can be reduced (to improve quality) or increased (to reduce bit rate). ROIs can be identified and quality settings can be adjusted based on input received from a user interface. An overlap setting can be determined for a portion of a picture that corresponds to an ROI overlap area. For example, an overlap setting is chosen from step sizes corresponding to a first overlapping ROI and a second overlapping ROI, or from relative reductions in step size corresponding to the first ROI and the second ROI. ROIs can be parameterized by information (e.g., using data structures) that indicates spatial dimensions of the ROIs and quality adjustment information (e.g., dead zone information, step size information, and quantization mode information).

Abstract: A video encoder identifies one or more portions of a video picture that contain DC shift blocks and adjusts quantization (e.g., by selecting a smaller quantization step size) to reduce contouring artifacts when the picture is reconstructed. The encoder can identify the portion(s) of the picture that contain DC shift blocks by identifying one or more gradient slope regions in the picture and analyzing quantization effects on DC coefficients in the gradient slope region(s). The encoder can select a coarser quantization step size for a high-texture picture portion.

Abstract: Techniques and tools are described for encoding animation video. In some embodiments, a video encoder designates animation video for encoding as animation content, which typically involves changing one or more encoder settings or rules to improve encoding performance for the animation content. When the encoder encodes the animation video, the encoder detects edges in the animation video using texture and changes settings for areas that include detected edges so as to improve encoding quality for the areas. In some embodiments, a video encoder adjusts differential quantization rules and quantizes animation video according to the adjusted differential quantization rules.

Abstract: Quality settings established by an encoder are adjusted based on information associated with regions of interest (“ROIs”). For example, quantization step sizes can be reduced (to improve quality) or increased (to reduce bit rate). ROIs can be identified and quality settings can be adjusted based on input received from a user interface. An overlap setting can be determined for a portion of a picture that corresponds to an ROI overlap area. For example, an overlap setting is chosen from step sizes corresponding to a first overlapping ROI and a second overlapping ROI, or from relative reductions in step size corresponding to the first ROI and the second ROI. ROIs can be parameterized by information (e.g., using data structures) that indicates spatial dimensions of the ROIs and quality adjustment information (e.g., dead zone information, step size information, and quantization mode information).

Abstract: Quality settings established by an encoder are adjusted based on information associated with regions of interest (“ROIs”). For example, quantization step sizes can be reduced (to improve quality) or increased (to reduce bit rate). ROIs can be identified and quality settings can be adjusted based on input received from a user interface. An overlap setting can be determined for a portion of a picture that corresponds to an ROI overlap area. For example, an overlap setting is chosen from step sizes corresponding to a first overlapping ROI and a second overlapping ROI, or from relative reductions in step size corresponding to the first ROI and the second ROI. ROIs can be parameterized by information (e.g., using data structures) that indicates spatial dimensions of the ROIs and quality adjustment information (e.g., dead zone information, step size information, and quantization mode information).

Abstract: A state client is configured to allow a user to specify a meeting-specific state, such as that the user is running late for a meeting, checked in to the meeting, or unable to attend the meeting. A state service stores data identifying the user's meeting-specific state. The state service also responds to requests for the state of the user. In one implementation, when such a request is received, the state service determines whether the user is an invitee to the same meeting as the user requesting the state. If not, the state service returns a general-purpose state indicator for the user. If both users are invitees to the same meeting, the state service returns the meeting-specific state indicator, which may then be displayed by a state client.

Abstract: A meeting lifecycle management service manages various aspects of a meeting lifecycle. An indication of a newly scheduled meeting is received at the meeting lifecycle management service, and information related to the meeting is managed, via the meeting lifecycle management service, prior to the meeting, during the meeting, and after the meeting.

Abstract: A video encoder identifies one or more AC coefficients of each of plural blocks in the picture. The encoder identifies a threshold quantization step size such that the identified AC coefficient(s) of each of the plural blocks are nonzero after quantization according to the threshold quantization step size. The threshold quantization step size is such that quantization according to the next higher quantization step size would result in at least one of the identified AC coefficient(s) of at least one of the plural blocks being zero. For example, identifying the threshold quantization step size comprises identifying n top AC coefficients in each of four blocks of a macroblock, determining the smallest AC coefficient among the identified n top AC coefficients of the four blocks, and iteratively evaluating the smallest AC coefficient with respect to candidate quantization step sizes until the threshold quantization step size is identified.

Abstract: A video encoder identifies a current smooth region of a current picture in a sequence and performs temporal analysis by determining whether a corresponding region in at least one previous and/or future picture is smooth. Based at least in part on the temporal analysis, the encoder adjusts quantization in the current smooth region. An encoder determines a differential quantization interval for a sequence, the interval comprising an interval number. The interval constrains the encoder to skip differential quantization for at least the interval number of predicted pictures after a predicted differentially quantized picture. An encoder analyzes texture in a current picture and sets a smoothness threshold. The encoder compares texture data with the smoothness threshold and adjusts differential quantization for at least part of the current picture based on a finding of at least one smooth region in the current picture according to the smoothness threshold.

Abstract: A video encoder identifies a current smooth region of a current picture in a sequence and performs temporal analysis by determining whether a corresponding region in at least one previous and/or future picture is smooth. Based at least in part on the temporal analysis, the encoder adjusts quantization in the current smooth region. An encoder determines a differential quantization interval for a sequence, the interval comprising an interval number. The interval constrains the encoder to skip differential quantization for at least the interval number of predicted pictures after a predicted differentially quantized picture. An encoder analyzes texture in a current picture and sets a smoothness threshold. The encoder compares texture data with the smoothness threshold and adjusts differential quantization for at least part of the current picture based on a finding of at least one smooth region in the current picture according to the smoothness threshold.

Abstract: Construction and use of forward error correction codes is provided. A systematic MDS FEC code is obtained having a property wherein any set of contiguous or non-contiguous r packets can be lost during a data transmission of k data packets and r encoded packets and the original k packets can be recovered unambiguously. The systematic MDS FEC code is transformed into a (k+r, k) systematic MDS FEC code that guarantees at least one of the encoded packets is a parity packet. The starting systematic MDS FEC code may be Cauchy-based, and the transformation code derived from the starting Cauchy-based MDS FEC code allows for very efficient initialization, encoding and decoding operations.

Abstract: Techniques and tools are described for encoding animation video. In some embodiments, a video encoder designates animation video for encoding as animation content, which typically involves changing one or more encoder settings or rules to improve encoding performance for the animation content. When the encoder encodes the animation video, the encoder detects edges in the animation video using texture and changes settings for areas that include detected edges so as to improve encoding quality for the areas. In some embodiments, a video encoder adjusts differential quantization rules and quantizes animation video according to the adjusted differential quantization rules.

Abstract: Quality settings established by an encoder are adjusted based on information associated with regions of interest (“ROIs”). For example, quantization step sizes can be reduced (to improve quality) or increased (to reduce bit rate). ROIs can be identified and quality settings can be adjusted based on input received from a user interface. An overlap setting can be determined for a portion of a picture that corresponds to an ROI overlap area. For example, an overlap setting is chosen from step sizes corresponding to a first overlapping ROI and a second overlapping ROI, or from relative reductions in step size corresponding to the first ROI and the second ROI. ROIs can be parameterized by information (e.g., using data structures) that indicates spatial dimensions of the ROIs and quality adjustment information (e.g., dead zone information, step size information, and quantization mode information).

Abstract: A video encoder identifies one or more portions of a video picture that contain DC shift blocks and adjusts quantization (e.g., by selecting a smaller quantization step size) to reduce contouring artifacts when the picture is reconstructed. The encoder can identify the portion(s) of the picture that contain DC shift blocks by identifying one or more gradient slope regions in the picture and analyzing quantization effects on DC coefficients in the gradient slope region(s). The encoder can select a coarser quantization step size for a high-texture picture portion.