The effect of the collection is as follows:
Here we see that the size of the collected image is 2592X1944 = 5038848 which is about 500W pixels. It looks very clear ~ really satisfied! !
Here are the relevant parameters of the raspistill command and the specific effect of the experiment:
-v: debug information view
-w: image width
-h: image height
-rot: image rotation angle, only supports 0, 90, 180, 270 degrees (explain here, the test found that the input of other angles will be converted to these four Angles)
-o: image output address, such as image.jpg, if the file name is "-", send the output to the standard output device
-t: wait time before obtaining the image, the default is 5000, which is 5 seconds
-tl : How often to perform image capture
Execute the following instructions:
raspistill -o image%d.jpg -rot 180 -w 1024 -h 768 -t 20000 -tl 5000 -v
Then the following will output a series of captured information,
Like the size of the picture 
,
The total capture time of the picture 
,
Whether the image is rotated,
Whether to reverse horizontally and vertically:
Here is the result of the final capture:
Note: Here we explain the correlation between the number of pictures collected and the -t parameter and -tl parameter: N_Picture = -t (wait time before acquiring image) / -tl (how often to perform capture time) + 1. So there are 20,000 / 5000 + 1 = 5 pictures