Merge commit '14f031d7ecfabba0ef02776d4516aa3dcb7c40d8'

* commit '14f031d7ecfabba0ef02776d4516aa3dcb7c40d8':
  dv: use AVStream.index instead of abusing AVStream.id
  lavfi: add ashowinfo filter
  avcodec: Add a RFC 3389 comfort noise codec
  lpc: Add a function for calculating reflection coefficients from samples
  lpc: Add a function for calculating reflection coefficients from autocorrelation coefficients
  lavr: document upper bound on number of output samples.
  lavr: add general API usage doxy
  indeo3: remove duplicate capabilities line.
  fate: ac3: Add dependencies

Conflicts:
	Changelog
	doc/filters.texi
	libavcodec/Makefile
	libavcodec/allcodecs.c
	libavcodec/avcodec.h
	libavcodec/codec_desc.c
	libavcodec/version.h
	libavfilter/Makefile
	libavfilter/af_ashowinfo.c
	libavfilter/allfilters.c
	libavfilter/version.h
	libavutil/avutil.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 34 insertions, 0 deletions

diff --git a/libavcodec/lpc.h b/libavcodec/lpc.h
index b9c35bd303..24f776a244 100644
--- a/libavcodec/lpc.h
+++ b/libavcodec/lpc.h
@@ -93,6 +93,9 @@ int ff_lpc_calc_coefs(LPCContext *s,
                       enum FFLPCType lpc_type, int lpc_passes,
                       int omethod, int max_shift, int zero_shift);
 
+int ff_lpc_calc_ref_coefs(LPCContext *s,
+                          const int32_t *samples, int order, double *ref);
+
 /**
  * Initialize LPCContext.
  */
@@ -112,6 +115,37 @@ void ff_lpc_end(LPCContext *s);
 #endif
 
 /**
+ * Schur recursion.
+ * Produces reflection coefficients from autocorrelation data.
+ */
+static inline void compute_ref_coefs(const LPC_TYPE *autoc, int max_order,
+                                     LPC_TYPE *ref, LPC_TYPE *error)
+{
+    int i, j;
+    LPC_TYPE err;
+    LPC_TYPE gen0[MAX_LPC_ORDER], gen1[MAX_LPC_ORDER];
+
+    for (i = 0; i < max_order; i++)
+        gen0[i] = gen1[i] = autoc[i + 1];
+
+    err    = autoc[0];
+    ref[0] = -gen1[0] / err;
+    err   +=  gen1[0] * ref[0];
+    if (error)
+        error[0] = err;
+    for (i = 1; i < max_order; i++) {
+        for (j = 0; j < max_order - i; j++) {
+            gen1[j] = gen1[j + 1] + ref[i - 1] * gen0[j];
+            gen0[j] = gen1[j + 1] * ref[i - 1] + gen0[j];
+        }
+        ref[i] = -gen1[0] / err;
+        err   +=  gen1[0] * ref[i];
+        if (error)
+            error[i] = err;
+    }
+}
+
+/**
  * Levinson-Durbin recursion.
  * Produce LPC coefficients from autocorrelation data.
  */