问LiteAVSDK_Professional中设置videoProcessDelegate不走回调？

TXLivePushConfig *config = [[TXLivePushConfig alloc] init];

config.customModeType |= CUSTOM_MODE_VIDEO_PREPROCESS;

TXLivePush *pusher = [[TXLivePush alloc] initWithConfig:config];

pusher.videoProcessDelegate = self;

发现没有进入- (GLuint)onPreProcessTexture:(GLuint)texture width:(CGFloat)width height:(CGFloat)height timestamp:(UInt64)timestamp这个方法，是需要配置别的东西吗