Image captured by opencv is not good as normal.
I have captured two images, one by opencv
another one by these command lines,
v4l2-ctl --set-fmt-video=width=640,height=480,pixelformat=3
v4l2-ctl --stream-mmap=3 --stream-count=1 --stream-to=somefile.jpg
As the result, image captured by opencv is not good as the remaining. The size of image captured by opencv is just 50kB and the remaining size is 110kb. Why are they different?
How can I set the setting of VideoCapture to get the good image? Please help me, thanks.
I think that size (in byte) are different because Jpeg compression quality is not the same
But the quality image captured by VideoCapture before using imwrite, it is also like that. It is not good at the one captured by v4l2-ctl.
May be an answer is ithis post