SwsFilter        2190 libswscale/swscale.c     SwsFilter dummyFilter= {NULL, NULL, NULL, NULL};
SwsFilter        2829 libswscale/swscale.c SwsFilter *sws_getDefaultFilter(float lumaGBlur, float chromaGBlur,
SwsFilter        2834 libswscale/swscale.c     SwsFilter *filter= av_malloc(sizeof(SwsFilter));