摘要:
Disclosed are improved constructions for power transformers and reactors having windings of tape-formed conductor material which tend to reduce additional losses in the windings. In the improved construction for a power transformer or reactor comprising a core containing magnetic material and having legs and a yoke and comprising windings including a tape-formed conductor material arranged concentrically around the core legs, the innermost of the windings has a first portion located nearest the core leg which has an axial length greater than the length of the portion of the winding located radially outside said first portion. The first portion thereby forms a cylindrical shield for controlling the magnetic leakage flux appearing outside the ends of the winding.
摘要:
A video data processing apparatus is provided comprising processing circuitry for performing video processing operations requiring access to video reference frames, and a memory management unit configured to translate virtual addresses into physical addresses. Translation circuitry is provided responsive to a memory access request for reference frame pixel data issued by the processing circuitry to perform a translation process on video reference frame information such that the set of input values for at least one hash function in the memory management unit comprises video reference frame identifier bits contained with the video reference frame information. This approach has been found to reduce the frequency of aliasing in the memory management unit when retrieving video reference frames.
摘要:
A video processing apparatus and method are provided, the video processing apparatus comprising first stage video processing circuitry and second stage video processing circuitry. The first stage video processing circuitry receives input video data and performs one or more processing operations on the input video data to generate an intermediate representation of the input video data. The intermediate representation comprises first and second separate data portions, with the first data portion containing transient data derived from the input video data and the second data portion containing long term data derived from the input video data. Transient data is only required for processing of a single video frame, while the long term data is required for processing of at least two video frames. The first stage video processing circuitry is arranged to output the first and second separate data portions for storing in a buffer, and the second stage video processing circuitry then retrieves the first and second data portions from the buffer and performs one or more further processing operations on those data portions in order to generate output video data. The transient data is compressed prior to being stored in the buffer, and then decompressed when retrieved from the buffer by the second stage video processing circuitry. Such an approach enables the operations of the second stage video processing circuitry to be decoupled from the operations of the first stage video processing circuitry, while reducing the storage capacity requirements of the buffer.
摘要:
The present invention provides filter circuitry for reducing noise in an input stream of image signals having luminance and chrominance components. Spatial filter circuitry is provided which, for a current image signal of the input stream, generates a spatially filtered internal signal from at least the luminance component of the current image signal. Comparison circuitry is configured to compare the current image signal with temporal data derived from multiple image signals of the input stream, and to generate a control signal dependent on the comparison. Combining circuitry is then used to combine, in a ratio determined by the control signal, the spatially filtered internal signal with at least a luminance component derived from the temporal data, in order to generate at least the luminance component of a current output image signal that forms a noise reduced version of the current image signal. Such a form of filter circuitry has been found to provide a filtered stream of image signals with significant noise suppression, and is particularly well suited to providing a filtered stream of image signals for input to video encoding circuitry, enabling significant improvements in the efficiency of the encoding circuitry by virtue of the manner in which the noise is suppressed.
摘要:
A data processing apparatus is provided comprising a plurality of master devices configured to issue memory access requests including virtual addresses. A memory management unit is configured to receive memory access requests and to translate a virtual address included in a memory access request from a requesting master device into a physical address indicating a storage location in memory. The memory management unit has an internal storage unit having a plurality of entries wherein indications of corresponding virtual address portions and physical address portions are stored. The memory management unit is configured to select an entry of the internal storage unit in dependence on the virtual address and an identifier of the requesting master device. Conflict between the master devices in their usage of the internal storage unit is thus avoided.
摘要:
The present invention provides filter circuitry for reducing noise in an input stream of image signals having luminance and chrominance components. Spatial filter circuitry is provided which, for a current image signal of the input stream, generates a spatially filtered internal signal from at least the luminance component of the current image signal. Comparison circuitry is configured to compare the current image signal with temporal data derived from multiple image signals of the input stream, and to generate a control signal dependent on the comparison. Combining circuitry is then used to combine, in a ratio determined by the control signal, the spatially filtered internal signal with at least a luminance component derived from the temporal data, in order to generate at least the luminance component of a current output image signal that forms a noise reduced version of the current image signal. Such a form of filter circuitry has been found to provide a filtered stream of image signals with significant noise suppression, and is particularly well suited to providing a filtered stream of image signals for input to video encoding circuitry, enabling significant improvements in the efficiency of the encoding circuitry by virtue of the manner in which the noise is suppressed.
摘要:
A data processing apparatus and method are provided for performing a predetermined rearrangement operation. The data processing apparatus comprises a vector register bank having a plurality of vector registers, with each vector register comprising a plurality of storage cells such that the plurality of vector registers provide a matrix of storage cells. Each storage cell is arranged to store a data element. A vector processing unit is provided for executing a sequence of vector instructions in order to apply operations to the data elements held in the vector register bank. Responsive to a vector matrix rearrangement instruction specifying a predetermined rearrangement operation to be performed on the data elements in the matrix of storage cells, the vector processing unit is arranged to issue a set rearrangement enable signal to the vector register bank. The write interface of the vector register bank is modified to provide not only a first input for receiving the data elements generated by the vector processing unit during normal execution, but also has a second input coupled via a data rearrangement path to the matrix of storage cells via which the data elements currently stored in the matrix of storage cells are provided to the write interface in a rearranged form representing the arrangement of data elements that would be obtained by performance of the predetermined rearrangement operation. When the rearrangement enable signal is set, the write interface then performs a write operation to the storage cells of the matrix using the data elements received at the second input. This enables the predetermined rearrangement operation to be performed at high speed and with significantly less complexity than in prior art systems.
摘要:
An industrial robot has a position controller for each one of the axes of the robot and a computer for control of the robot. The computer continuously determines, with the aid of a mathematical model set up in advance, in dependence on the robot configuration and load in question, the mass moment of inertia of the axes, the coupled mass moment of inertia, and the moment caused by gravity. From the relationships between acceleration/deceleration and the drive motor torque for the different axes, the maximum available acceleration/deceleration for the axis is determined while assuming that maximum motor torque prevails for each axis. For each axis this value is compared with the maximum acceleration/deceleration value that may be allowed from the point of view of stability. On the basis of the lower of these values, optimum gain is determined and set in the position controller and/or a path planning parameter.
摘要:
A data processing apparatus is provided comprising a plurality of master devices configured to issue memory access requests including virtual addresses. A memory management unit is configured to receive memory access requests and to translate a virtual address included in a memory access request from a requesting master device into a physical address indicating a storage location in memory. The memory management unit has an internal storage unit having a plurality of entries wherein indications of corresponding virtual address portions and physical address portions are stored. The memory management unit is configured to select an entry of the internal storage unit in dependence on the virtual address and an identifier of the requesting master device. Conflict between the master devices in their usage of the internal storage unit is thus avoided.
摘要:
A data processing apparatus and method and provided for handling vector instructions. The data processing apparatus has a register data store with a plurality of registers arranged to store data elements. A vector processing unit is then used to execute a sequence of vector instructions, with the vector processing unit having a plurality of lanes of parallel processing and having access to the register data store in order to read data elements from, and write data elements to, the register data store during the execution of the sequence of vector instructions. A skip indication storage maintains a skip indicator for each of the lanes of parallel processing. The vector processing unit is responsive to a vector skip instruction to perform an update operation to set within the skip indication storage the skip indicator for a determined one or more lanes. The vector processing unit is responsive to a vector operation instruction to perform an operation in parallel on data elements input to the plurality of lanes of parallel processing, but to exclude from the performance of the operation any lane whose associated skip indicator is set. This allows the operation specified by vector instructions to be performed conditionally within each of the lanes of parallel processing without any modification to the vector instructions that are specifying those operations.