Same-parity fields are used to improve the accuracy of motion estimation. It estimates the motion by comparing the sum of absolute block difference(SAD) between 4 fields with the threshold of motion.

运动估计通过比较同极性场的像素块绝对值差和（SAD）与运动阈值实现运动估计，并且利用前一场的运动信息进行鲁棒性处理，提高运动检测的精度。

youdao

As one would expect, once block size gets large, it makes no difference whether block-level compression is used.

正如预期的那样，一旦块大小变大，是否使用块级别压缩并没有区别。

youdao

I was surprised to see that block size makes very little difference to the running times of any of the examined transformations.

块大小对所有被检查转换的运行时间产生如此小的影响使我觉得很奇怪。

youdao

For one, they usually have dirt, grease and oil stuck under their fingernails, and they know the difference between a small block and a cinder block.

FORBES: Magazine Article

It suggests that London set Scottish rates at 10p less than those for Britain as a whole, and cut its block grant by the amount that the difference in rates might be expected to raise.

ECONOMIST: Devolution finances

Guys are getting in lanes to block shots, and it certainly made the difference.

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