Based　on　the　characteristics　that　the　farmlands　and　ponds　have　significant　corners　in　high-resolution　image,　the　extraction　of　farmlands　and　ponds　is　achieved　accurately　in　this　paper.　During　the　corner　extraction　procedure,　according　to　the　sensitivity　of　the　corner　direction　change,　traditional　algorithm　was　improved　with　bidirectional　analysis　technology　and　more　robust　bidirectional　TK　(Tomasi-Kanade)　corner　detector　was　proposed.　COVPEX　(Corner　validation　based　on　corner　property　extraction)　was　used　to　validate　result　of　corner　detection.　Authors　found　not　only　the　pseudo-corners　which　were　almost　useless　for　image　analysis　but　also　the　corner-clusters　were　presented　in　the　validation　result.　The　pseudo-corners　reduce　rationality　of　the　results,　and　the　corner-clusters　destroy　the　uniqueness　of　corner.　To　solve　the　problems,　COVPEX　algorithm　was　improved　by　associating　with　multi-scale　analysis　technology,　multi-scale　COVPEX　algorithm　and　the　＇removal　corner-cluster＇　operation　were　proposed.　The　results　showed　that　the　accuracy　and　rationality　of　corner　extraction　were　significantly　improved.