int ff_log2(uint32_t value);
/**
- * \brief Calculates sum of array elements multiplications
- * \param speech array with input data
- * \param length number elements to proceed
- * \param offset offset for calculation sum of s[i]*s[i+offset]
+ * \brief Calculates sum of array element multiplications
+ * \param speech input data array
+ * \param length number of elements
+ * \param offset offset for calculation of sum of s[i]*s[i+offset]
* \param shift right shift by this value will be done before multiplication
*
* \return sum of multiplications
*/
/**
- * \brief keep distance between LSFs.
+ * \brief ensure a minimum distance between LSFs
* \param lsfq [in/out] LSF to check and adjust
* \param lsfq_min_distance minimum distance between LSFs
* \param lsfq_min minimum allowed LSF value
* \param lsp [out] LSP coefficients (-0x8000 <= (0.15) < 0x8000)
* \param lsf normalized LSF coefficients (0 <= (2.13) < 0x2000 * PI)
*
- * \remark It is safe to pass the same array in lsf and lsp parameters
+ * \remark It is safe to pass the same array into the lsf and lsp parameters.
*/
void ff_acelp_lsf2lsp(int16_t *lsp, const int16_t *lsf);
/**
* \brief Interpolate LSP for the first subframe and convert LSP -> LP for both subframes (3.2.5 and 3.2.6 of G.729)
- * \param lp_1st [out] decoded LP coefficients for 1st subframe (-0x8000 <= (3.12) < 0x8000)
+ * \param lp_1st [out] decoded LP coefficients for first subframe (-0x8000 <= (3.12) < 0x8000)
* \param lp_2nd [out] decoded LP coefficients for second subframe (-0x8000 <= (3.12) < 0x8000)
* \param lsp_2nd LSP coefficients of the second subframe (-0x8000 <= (0.15) < 0x8000)
- * \param lsp_prev past LSP coefficients (-0x8000 <= (0.15) < 0x8000)
+ * \param lsp_prev LSP coefficients from the second subframe of the previous frame (-0x8000 <= (0.15) < 0x8000)
*/
void ff_acelp_lp_decode(int16_t* lp_1st, int16_t* lp_2nd, const int16_t* lsp_2nd, const int16_t* lsp_prev);