FFTComplex         53 3rdparty/include/ffmpeg_/libavcodec/avfft.h void av_fft_permute(FFTContext *s, FFTComplex *z);
FFTComplex         59 3rdparty/include/ffmpeg_/libavcodec/avfft.h void av_fft_calc(FFTContext *s, FFTComplex *z);