Grammar fixes and improvements for the new ACELP code

Originally committed as revision 13000 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/acelp_math.h

@@ -49,10 +49,10 @@ int ff_exp2(uint16_t power);
 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

libavcodec/lsp.h

@@ -27,7 +27,7 @@
 */
 
 /**
- * \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
@@ -40,7 +40,7 @@ void ff_acelp_reorder_lsf(int16_t* lsfq, int lsfq_min_distance, int lsqf_min, in
  * \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);
 
@@ -53,10 +53,10 @@ void ff_acelp_lsp2lpc(int16_t* lp, const int16_t* lsp);
 
 /**
  * \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);