From 25accf93ad7b0ad3e2a17718e689c05fbc5b5698 Mon Sep 17 00:00:00 2001
From: Mans Rullgard <mans@mansr.com>
Date: Mon, 2 Jul 2012 13:51:04 +0100
Subject: [PATCH] flacdec: move lpc filter to flacdsp

Signed-off-by: Mans Rullgard <mans@mansr.com>
---
 libavcodec/flacdec.c | 35 ++--------------------------------
 libavcodec/flacdsp.c | 45 ++++++++++++++++++++++++++++++++++++++++++++
 libavcodec/flacdsp.h |  2 ++
 3 files changed, 49 insertions(+), 33 deletions(-)

diff --git a/libavcodec/flacdec.c b/libavcodec/flacdec.c
index daa5bd8daf..7295e2e1ce 100644
--- a/libavcodec/flacdec.c
+++ b/libavcodec/flacdec.c
@@ -360,7 +360,7 @@ static int decode_subframe_fixed(FLACContext *s, int channel, int pred_order,
 static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order,
                                int bps)
 {
-    int i, j;
+    int i;
     int coeff_prec, qlevel;
     int coeffs[32];
     int32_t *decoded = s->decoded[channel];
@@ -389,38 +389,7 @@ static int decode_subframe_lpc(FLACContext *s, int channel, int pred_order,
     if (decode_residuals(s, channel, pred_order) < 0)
         return -1;
 
-    if (s->bps > 16) {
-        int64_t sum;
-        for (i = pred_order; i < s->blocksize; i++) {
-            sum = 0;
-            for (j = 0; j < pred_order; j++)
-                sum += (int64_t)coeffs[j] * decoded[i-j-1];
-            decoded[i] += sum >> qlevel;
-        }
-    } else {
-        for (i = pred_order; i < s->blocksize-1; i += 2) {
-            int c;
-            int d = decoded[i-pred_order];
-            int s0 = 0, s1 = 0;
-            for (j = pred_order-1; j > 0; j--) {
-                c = coeffs[j];
-                s0 += c*d;
-                d = decoded[i-j];
-                s1 += c*d;
-            }
-            c = coeffs[0];
-            s0 += c*d;
-            d = decoded[i] += s0 >> qlevel;
-            s1 += c*d;
-            decoded[i+1] += s1 >> qlevel;
-        }
-        if (i < s->blocksize) {
-            int sum = 0;
-            for (j = 0; j < pred_order; j++)
-                sum += coeffs[j] * decoded[i-j-1];
-            decoded[i] += sum >> qlevel;
-        }
-    }
+    s->dsp.lpc(decoded, coeffs, pred_order, qlevel, s->blocksize);
 
     return 0;
 }
diff --git a/libavcodec/flacdsp.c b/libavcodec/flacdsp.c
index b7e074644e..fcee8e44c7 100644
--- a/libavcodec/flacdsp.c
+++ b/libavcodec/flacdsp.c
@@ -29,6 +29,49 @@
 #define SAMPLE_SIZE 32
 #include "flacdsp_template.c"
 
+static void flac_lpc_16_c(int32_t *decoded, const int coeffs[32],
+                          int pred_order, int qlevel, int len)
+{
+    int i, j;
+
+    for (i = pred_order; i < len - 1; i += 2) {
+        int c;
+        int d = decoded[i-pred_order];
+        int s0 = 0, s1 = 0;
+        for (j = pred_order-1; j > 0; j--) {
+            c = coeffs[j];
+            s0 += c*d;
+            d = decoded[i-j];
+            s1 += c*d;
+        }
+        c = coeffs[0];
+        s0 += c*d;
+        d = decoded[i] += s0 >> qlevel;
+        s1 += c*d;
+        decoded[i+1] += s1 >> qlevel;
+    }
+    if (i < len) {
+        int sum = 0;
+        for (j = 0; j < pred_order; j++)
+            sum += coeffs[j] * decoded[i-j-1];
+        decoded[i] += sum >> qlevel;
+    }
+}
+
+static void flac_lpc_32_c(int32_t *decoded, const int coeffs[32],
+                          int pred_order, int qlevel, int len)
+{
+    int i, j;
+
+    for (i = pred_order; i < len; i++) {
+        int64_t sum = 0;
+        for (j = 0; j < pred_order; j++)
+            sum += (int64_t)coeffs[j] * decoded[i-j-1];
+        decoded[i] += sum >> qlevel;
+    }
+
+}
+
 av_cold void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt)
 {
     switch (fmt) {
@@ -37,6 +80,7 @@ av_cold void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt)
         c->decorrelate[1] = flac_decorrelate_ls_c_32;
         c->decorrelate[2] = flac_decorrelate_rs_c_32;
         c->decorrelate[3] = flac_decorrelate_ms_c_32;
+        c->lpc            = flac_lpc_32_c;
         break;
 
     case AV_SAMPLE_FMT_S16:
@@ -44,6 +88,7 @@ av_cold void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt)
         c->decorrelate[1] = flac_decorrelate_ls_c_16;
         c->decorrelate[2] = flac_decorrelate_rs_c_16;
         c->decorrelate[3] = flac_decorrelate_ms_c_16;
+        c->lpc            = flac_lpc_16_c;
         break;
     }
 }
diff --git a/libavcodec/flacdsp.h b/libavcodec/flacdsp.h
index bb289eea13..fe5ca53177 100644
--- a/libavcodec/flacdsp.h
+++ b/libavcodec/flacdsp.h
@@ -25,6 +25,8 @@
 typedef struct FLACDSPContext {
     void (*decorrelate[4])(uint8_t **out, int32_t **in, int channels,
                            int len, int shift);
+    void (*lpc)(int32_t *samples, const int coeffs[32], int order,
+                int qlevel, int len);
 } FLACDSPContext;
 
 void ff_flacdsp_init(FLACDSPContext *c, enum AVSampleFormat fmt);