1 files changed, 22 insertions, 0 deletions
diff --git a/libavcodec/celp_filters.h b/libavcodec/celp_filters.h
index d33aafd229..4a9eb1c49b 100644
--- a/libavcodec/celp_filters.h
+++ b/libavcodec/celp_filters.h
@@ -91,4 +91,26 @@ void ff_celp_lp_synthesis_filterf(
         int buffer_length,
         int filter_length);
 
+/**
+ * LP zero synthesis filter.
+ * @param out [out] pointer to output buffer
+ * @param filter_coeffs filter coefficients.
+ * @param in input signal
+ *        - the array in[-filter_length, -1] must
+ *        contain the previous input of this filter
+ * @param buffer_length amount of data to process
+ * @param filter_length filter length (10 for 10th order LP filter)
+ *
+ * @note Output buffer must contain filter_length samples of past
+ *       speech data before pointer.
+ *
+ * Routine applies A(z) filter to given speech data.
+ */
+void ff_celp_lp_zero_synthesis_filterf(
+        float *out,
+        const float* filter_coeffs,
+        const float* in,
+        int buffer_length,
+        int filter_length);
+
 #endif /* AVCODEC_CELP_FILTERS_H */