AV_MATRIX_ENCODING_NB   71 libavresample/options.c     { "matrix_encoding",        "Matrixed Stereo Encoding", OFFSET(matrix_encoding),        AV_OPT_TYPE_INT,    {.i64 =  AV_MATRIX_ENCODING_NONE}, AV_MATRIX_ENCODING_NONE,     AV_MATRIX_ENCODING_NB-1, PARAM, "matrix_encoding" },
AV_MATRIX_ENCODING_NB  114 libswresample/options.c { "matrix_encoding"     , "set matrixed stereo encoding" , OFFSET(matrix_encoding), AV_OPT_TYPE_INT   ,{.i64 = AV_MATRIX_ENCODING_NONE}, AV_MATRIX_ENCODING_NONE,     AV_MATRIX_ENCODING_NB-1, PARAM, "matrix_encoding" },