 #define DESCR_BINS_V1        8
 #define MAGNIFY_V1           3.0f
 #define DESCR_V1_NUM_THREADS 32
+// #define DESCR_V1_NUM_THREADS 16
+// #define DESCR_V1_NUM_THREADS 8
 #define RPI_V1               (4.0f / M_PI)
 #define EPS_V1               1E-15
 


    /* reduction here */
    for (int i = 0; i < 8; i++) {
        dpt[i] += __shfl_down( dpt[i], 16 );
        dpt[i] += __shfl_down( dpt[i], 8 );
        dpt[i] += __shfl_down( dpt[i], 4 );
        dpt[i] += __shfl_down( dpt[i], 2 );
        dpt[i] += __shfl_down( dpt[i], 1 );

                      oct_obj.getDescriptors( level ),
                      oct_obj.getData( level ) );

                block.x = 32;
                block.y = 1;
                block.z = 1;

