1.What are the requests of uploaded images?
2.How Many Ways Can I Upload Images?
3.What If It Says "The size of picture should be larger than 30*30px!"?
4.What If It Says "Upload Failed, Error Code: xxx"?
There could be two reasons:
a.The image you uploaded is other file format instead of JPG, JPEG, PNG, GIF, WBMP. So you can convert the format of the image with photo editors then upload it.
B. The picture you upload is too large.