MULTI-DIMENSIONAL THREADS

Each CUDA kernel is executed by a grid, which contains

  • a 3d thread blocks
  • a 3d threads

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Each thread executes the same program

  • on distinct data inputs
  • single program multipul data model (SPMD)

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like the operation system:

  • cooperation happens within a block.
  • threads in different block cooperate less

    MAPPING THREADS TO MULTIDIMENSIONAL DATA

    How to calculate the gird?

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    每个block中的thread 处理一个图片中的像素

    How to deal with the idle threads

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    如何计算当前thread对应在图像中的行数和列数

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    而当前的如果是灰度图，拿到的就是真实的下标，而RGB图片有三个通道，并且张量形式为（width,height,channels），每个像素都有三个分量，需要乘以3才是当前图像中像素的位置在张量中的下标
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