lpc: use function pointers, in preparation for asm

Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

libavcodec/lpc.c

@@ -212,7 +212,7 @@ int ff_lpc_calc_coefs(LPCContext *s,
 
                 if(pass){
                     double eval, inv, rinv;
-                    eval= avpriv_evaluate_lls(&m[(pass-1)&1], var+1, max_order-1);
+                    eval= m[(pass-1)&1].evaluate_lls(&m[(pass-1)&1], var+1, max_order-1);
                     eval= (512>>pass) + fabs(eval - var[0]);
                     inv = 1/eval;
                     rinv = sqrt(inv);
@@ -222,7 +222,7 @@ int ff_lpc_calc_coefs(LPCContext *s,
                 }else
                     weight++;
 
-                avpriv_update_lls(&m[pass&1], var);
+                m[pass&1].update_lls(&m[pass&1], var);
             }
             avpriv_solve_lls(&m[pass&1], 0.001, 0);
         }

libavutil/lls.c

@@ -32,13 +32,7 @@
 #include "version.h"
 #include "lls.h"
 
-av_cold void avpriv_init_lls(LLSModel *m, int indep_count)
+static void update_lls(LLSModel *m, double *var)
-{
-    memset(m, 0, sizeof(LLSModel));
-    m->indep_count = indep_count;
-}
-
-void avpriv_update_lls(LLSModel *m, double *var)
 {
     int i, j;
 
@@ -106,7 +100,7 @@ void avpriv_solve_lls(LLSModel *m, double threshold, unsigned short min_order)
     }
 }
 
-double avpriv_evaluate_lls(LLSModel *m, double *param, int order)
+static double evaluate_lls(LLSModel *m, double *param, int order)
 {
     int i;
     double out = 0;
@@ -117,6 +111,14 @@ double avpriv_evaluate_lls(LLSModel *m, double *param, int order)
     return out;
 }
 
+av_cold void avpriv_init_lls(LLSModel *m, int indep_count)
+{
+    memset(m, 0, sizeof(LLSModel));
+    m->indep_count = indep_count;
+    m->update_lls = update_lls;
+    m->evaluate_lls = evaluate_lls;
+}
+
 #if FF_API_LLS_PRIVATE
 av_cold void av_init_lls(LLSModel *m, int indep_count)
 {
@@ -124,7 +126,7 @@ av_cold void av_init_lls(LLSModel *m, int indep_count)
 }
 void av_update_lls(LLSModel *m, double *param, double decay)
 {
-    avpriv_update_lls(m, param);
+    m->update_lls(m, param);
 }
 void av_solve_lls(LLSModel *m, double threshold, int min_order)
 {
@@ -132,7 +134,7 @@ void av_solve_lls(LLSModel *m, double threshold, int min_order)
 }
 double av_evaluate_lls(LLSModel *m, double *param, int order)
 {
-    return avpriv_evaluate_lls(m, param, order);
+    return m->evaluate_lls(m, param, order);
 }
 #endif /* FF_API_LLS_PRIVATE */
 
@@ -159,10 +161,10 @@ int main(void)
         var[1] = var[0] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
         var[2] = var[1] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
         var[3] = var[2] + av_lfg_get(&lfg) / (double) UINT_MAX - 0.5;
-        avpriv_update_lls(&m, var);
+        m.update_lls(&m, var);
         avpriv_solve_lls(&m, 0.001, 0);
         for (order = 0; order < 3; order++) {
-            eval = avpriv_evaluate_lls(&m, var + 1, order);
+            eval = m.evaluate_lls(&m, var + 1, order);
             printf("real:%9f order:%d pred:%9f var:%f coeffs:%f %9f %9f\n",
                    var[0], order, eval, sqrt(m.variance[order] / (i + 1)),
                    m.coeff[order][0], m.coeff[order][1],

libavutil/lls.h

@@ -37,12 +37,23 @@ typedef struct LLSModel {
     double coeff[MAX_VARS][MAX_VARS];
     double variance[MAX_VARS];
     int indep_count;
+    /**
+     * Take the outer-product of var[] with itself, and add to the covariance matrix.
+     * @param m this context
+     * @param var training samples, starting with the value to be predicted
+     */
+    void (*update_lls)(struct LLSModel *m, double *var);
+    /**
+     * Inner product of var[] and the LPC coefs.
+     * @param m this context
+     * @param var training samples, excluding the value to be predicted
+     * @param order lpc order
+     */
+    double (*evaluate_lls)(struct LLSModel *m, double *var, int order);
 } LLSModel;
 
 void avpriv_init_lls(LLSModel *m, int indep_count);
-void avpriv_update_lls(LLSModel *m, double *param);
 void avpriv_solve_lls(LLSModel *m, double threshold, unsigned short min_order);
-double avpriv_evaluate_lls(LLSModel *m, double *param, int order);
 
 #if FF_API_LLS_PRIVATE
 void av_init_lls(LLSModel *m, int indep_count);