<camera class="camera" style="height: calc( 85vh - {{statusHeight}}px);" wx:if="{{!show}}" device-position="{{ devicePosition ? 'black' : 'front'}}" flash="off" binderror="error">
<view class="id_m" style="height: calc( 85vh - {{statusHeight}}px);">
<image class="img" src="{{ imageBaseUrl + 'certification/human_face.png'}}" mode="aspectFill"> </image>
</view>
</camera>
这好像应该是back