diff options
Diffstat (limited to 'libavcodec/lsp.h')
| -rw-r--r-- | libavcodec/lsp.h | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/libavcodec/lsp.h b/libavcodec/lsp.h index 0fa585016a..9aee5fad7d 100644 --- a/libavcodec/lsp.h +++ b/libavcodec/lsp.h @@ -40,6 +40,19 @@ void ff_acelp_reorder_lsf(int16_t* lsfq, int lsfq_min_distance, int lsfq_min, int lsfq_max, int lp_order); /** + * Adjust the quantized LSFs so they are increasing and not too close. + * + * This step is not mentioned in the AMR spec but is in the reference C decoder. + * Omitting this step creates audible distortion on the sinusoidal sweep + * test vectors in 3GPP TS 26.074. + * + * @param[in,out] lsf LSFs in Hertz + * @param min_spacing minimum distance between two consecutive lsf values + * @param size size of the lsf vector + */ +void ff_set_min_dist_lsf(float *lsf, float min_spacing, int order); + +/** * \brief Convert LSF to LSP * \param lsp [out] LSP coefficients (-0x8000 <= (0.15) < 0x8000) * \param lsf normalized LSF coefficients (0 <= (2.13) < 0x2000 * PI) |