static inline int find_min_book(float maxval, int sf)
{
    float Q = ff_aac_pow2sf_tab[POW_SF2_ZERO - sf + SCALE_ONE_POS - SCALE_DIV_512];
    float Q34 = sqrtf(Q * sqrtf(Q));
    int qmaxval, cb;
    qmaxval = maxval * Q34 + C_QUANT;
    if (qmaxval >= (FF_ARRAY_ELEMS(aac_maxval_cb)))
        cb = 11;
    else
        cb = aac_maxval_cb[qmaxval];
    return cb;
}