With a JPG picture (file size 3 m), the same quality of compression quality.

On the front end using canvas. ToDataURL (imgType, quality); Compressed file size is 300 KB,

In c # using EncoderParameter (imgType, quality); Compressed file size is 500 KB,

The result shows that the quality is the same, but c # compressed file size is much larger,

If using this method in the c # for the other information of pictures,