摘要:
Video coding systems incorporate techniques for deriving scalars W and/or O for use in weighted prediction. W represents a scaling factor and O represents an offset value. Given a frame of input video to be coded, a prediction match may be established one or more reference frames. The input frame may be parsed into a plurality of regions. Thereafter the scaling factor W and/or offset value O may be derived by developing a system of equations relating a predicted pixel to the pixel in the frame by the scaling factor W and/or offset value O. Equations within the system may be prioritized according to priority among regions, and scaling factor W and/or offset value O may be solved for. The scaling factor W and/or offset value O may be used during weighted prediction of the input frame.
摘要:
Video coders may perform perspective transformation of reference frames during coding in a manner that conserves processing resources. When a new input frame is available for coding, a camera position for the input frame may be estimated. A video coder may search for reference pictures having similar camera positions as the position of the input frame and, for each reference picture identified, the video coder may perform a prediction search to identify a reference picture that is the best prediction match for the input frame. Once the video coder identifies a reference picture to serve as a prediction source for the input frame, the video coder may derive a transform to match the reference frame data to the input frame data and may transform the reference picture accordingly. The video coder may code the input frame using the transformed reference picture as a prediction reference and may transmit coded frame data and the camera position of the input frame to a decoder. Thus, the video coder may perform derivation and execution of transforms on a limited basis which conserves system resources.
摘要:
In a video coding/decoding system, reference picture caches in a video coder and decoder may be partitioned dynamically based on camera and background motion can lead to improved coding efficiency and coding quality. When a camera is fixed and therefore exhibits low motion, a system may allocate larger portions of the reference picture cache to storage of long term reference frames. In this case, foreground elements of an image (for example, a person) may move in front of a relatively fixed background. Increasing the number of long term reference frames can increase the chances that, no matter where the foreground elements are within a frame currently being coded, the reference picture cache will contain at least one frame that provides an adequate prediction match to background elements within the new frame. Thus the background elements uncovered in the current frame can be coded at high quality with a low number of bits. When a camera exhibits high motion, the system may allocate larger portions of the reference picture cache to storage of short term reference frames.
摘要:
A system and method for efficiently performing motion estimation during temporal prediction for coding. When a new frame is presented for coding, an encoder may identify a limited number of pixel blocks within the input frame that are complex. The encoder may perform motion estimation searches to find reference frame(s) that are adequate prediction references for the complex pixel blocks. The encoder may search for prediction references for the remaining pixel blocks of the new frame, confining the search to the reference frame(s) that were selected as prediction references of the complex pixel blocks.
摘要:
In a video coding/decoding system, reference picture caches in a video coder and decoder may be partitioned dynamically based on camera and background motion can lead to improved coding efficiency and coding quality. When a camera is fixed and therefore exhibits low motion, a system may allocate larger portions of the reference picture cache to storage of long term reference frames. In this case, foreground elements of an image (for example, a person) may move in front of a relatively fixed background. Increasing the number of long term reference frames can increase the chances that, no matter where the foreground elements are within a frame currently being coded, the reference picture cache will contain at least one frame that provides an adequate prediction match to background elements within the new frame. Thus the background elements uncovered in the current frame can be coded at high quality with a low number of bits. When a camera exhibits high motion, the system may allocate larger portions of the reference picture cache to storage of short term reference frames.
摘要:
A system and method for efficiently performing motion estimation during temporal prediction for coding. When a new frame is presented for coding, an encoder may identify a limited number of pixel blocks within the input frame that are complex. The encoder may perform motion estimation searches to find reference frame(s) that are adequate prediction references for the complex pixel blocks. The encoder may search for prediction references for the remaining pixel blocks of the new frame, confining the search to the reference frame(s) that were selected as prediction references of the complex pixel blocks.
摘要:
Selecting a coding mode for coding video data by measuring a distortion sensitivity threshold for a pixel block, calculating a distortion threshold representative of the maximum distortion that may be effectively masked by the brightness and texture of the pixel block, estimating the distortion induced by coding the pixel block according to skip mode and coding the source pixel block with a predictive coding technique if the estimated distortion value exceeds the distortion threshold. The distortion sensitivity threshold may include, for example, a brightness value or a texture value. The contrast between the pixel block and the surrounding pixel blocks may also be considered such that if the contrast exceeds a contrast threshold calculated based on the measurement of brightness and texture, the source pixel block may be coded with a predictive coding technique even if the estimated distortion value does not exceed the distortion threshold.
摘要:
A heat-dissipation method comprises providing a heat-transfer module and a heat-dissipation module, wherein the heat-transfer module is disposed in a portable electronic device, and the heat-dissipation module is disposed in a battery charger. The heat-dissipation module then contacts the heat-transfer module to remove heat from the electronic device via conduction. Finally, the heat-dissipation module dissipates heat via conduction or convection.
摘要:
A transmission device of a handheld electronic device including a housing having an inlet and an outlet, a fan installed within the housing for generating airflow from the inlet to the outlet and a guide tube installed on the housing having a first opening and a second opening, the first opening is located at the outlet side, the second opening is coupled to an opening of the handheld electronic device in a detachable manner to allow airflow generated by the fan into the handheld electronic device, the guide tube can improve cooling effect of the transmission device and the transmission device is capable of cooling the handheld electronic device to solve the heating problem while the handheld electronic device is being utilized.
摘要:
A compatible connector for first and second joints having different pin quantities is disclosed. The connector includes a base, at least one first pin, and at least one second pin. The base includes a first connecting surface and a second connecting surface. The first pins are disposed on the first connecting surface and the quantity of the first pins is the same as the pin quantity of the first joint. In addition, the second pins are disposed on the second connecting surface and the total quantity of the second pins and the first pins is the same as the pin quantity of the second joint.