OSS 视频封面

<video src="地址" poster="地址+ '?x-oss-process=video/snapshot,t_1000,f_jpg,w_800,h_600,m_fast'"></video>
?x-oss-process=video/snapshot,t_1000,f_jpg,w_800,h_600,m_fast

w_ 和 h_  是宽高。一般情况下不写。

?x-oss-process=video/snapshot,t_1000,f_jpg,m_fast

https://help.aliyun.com/document_detail/64555.html