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OpenCV IO Mat #473

Open junxnone opened 3 months ago

junxnone commented 3 months ago

OpenCV Mat

elemSize

元素大小
元素指 CV_8UC1/CV_8UC3/CV_32FC1/...
elemSize1 : elemSize 一个通道 size

TYPE	elemSize	elemSize1
CV_8UC1	1	1
CV_8UC3	3	1
CV_16UC1	2	2
CV_16UC3	6	2
CV_32FC1	4	4
CV_32FC4	16	4
`...`	`...`	`...`

step(stride)

存储着各个维度占用的内存块的大小
step[0] = cols * elemSize
step[1] = elemSize
step1: 以 elemSize1 为单位

`.at`

访问元素
img.at(y, x)

`.ptr`

访问矩阵某行, 返回指向矩阵某行开始的地址
img->ptr(n)

Reference

OpenCV:Mat中的step、elemSize和任意内存访问