Aug 20 (Reuters) - Chinese search engine giant Baidu ( BIDU )

fell short of market estimates for quarterly

revenue on Wednesday, signaling persistent weakness in the

advertising market amid prolonged economic uncertainty.

The company reported total revenue of 32.71 billion yuan

($4.56 billion) during the second quarter, compared with

analysts' average estimate of 32.76 billion yuan, according to

data compiled by LSEG.

($1 = 7.1784 Chinese yuan renminbi)