flacdsp: move lpc encoding from FLAC encoder to FLACDSPContext

Also, templatize the functions for 16-bit and 32-bit sample range. This will
be used for 24-bit FLAC encoding.

1 files changed, 141 insertions, 0 deletions

diff --git a/libavcodec/flacdsp_lpc_template.c b/libavcodec/flacdsp_lpc_template.c
new file mode 100644
index 0000000000..269e64b3a8
--- /dev/null
+++ b/libavcodec/flacdsp_lpc_template.c
@@ -0,0 +1,141 @@
+/*
+ * This file is part of Libav.
+ *
+ * Libav is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * Libav is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with Libav; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <stdint.h>
+#include "libavutil/avutil.h"
+#include "mathops.h"
+
+#undef FUNC
+#undef sum_type
+#undef MUL
+#undef CLIP
+#undef FSUF
+
+#define FUNC(n) AV_JOIN(n ## _, SAMPLE_SIZE)
+
+#if SAMPLE_SIZE == 32
+#   define sum_type  int64_t
+#   define MUL(a, b) MUL64(a, b)
+#   define CLIP(x) av_clipl_int32(x)
+#else
+#   define sum_type  int32_t
+#   define MUL(a, b) ((a) * (b))
+#   define CLIP(x) (x)
+#endif
+
+#define LPC1(x) {           \
+    int c = coefs[(x)-1];   \
+    p0   += MUL(c, s);      \
+    s     = smp[i-(x)+1];   \
+    p1   += MUL(c, s);      \
+}
+
+static av_always_inline void FUNC(lpc_encode_unrolled)(int32_t *res,
+                                  const int32_t *smp, int len, int order,
+                                  const int32_t *coefs, int shift, int big)
+{
+    int i;
+    for (i = order; i < len; i += 2) {
+        int s  = smp[i-order];
+        sum_type p0 = 0, p1 = 0;
+        if (big) {
+            switch (order) {
+            case 32: LPC1(32)
+            case 31: LPC1(31)
+            case 30: LPC1(30)
+            case 29: LPC1(29)
+            case 28: LPC1(28)
+            case 27: LPC1(27)
+            case 26: LPC1(26)
+            case 25: LPC1(25)
+            case 24: LPC1(24)
+            case 23: LPC1(23)
+            case 22: LPC1(22)
+            case 21: LPC1(21)
+            case 20: LPC1(20)
+            case 19: LPC1(19)
+            case 18: LPC1(18)
+            case 17: LPC1(17)
+            case 16: LPC1(16)
+            case 15: LPC1(15)
+            case 14: LPC1(14)
+            case 13: LPC1(13)
+            case 12: LPC1(12)
+            case 11: LPC1(11)
+            case 10: LPC1(10)
+            case  9: LPC1( 9)
+                     LPC1( 8)
+                     LPC1( 7)
+                     LPC1( 6)
+                     LPC1( 5)
+                     LPC1( 4)
+                     LPC1( 3)
+                     LPC1( 2)
+                     LPC1( 1)
+            }
+        } else {
+            switch (order) {
+            case  8: LPC1( 8)
+            case  7: LPC1( 7)
+            case  6: LPC1( 6)
+            case  5: LPC1( 5)
+            case  4: LPC1( 4)
+            case  3: LPC1( 3)
+            case  2: LPC1( 2)
+            case  1: LPC1( 1)
+            }
+        }
+        res[i  ] = smp[i  ] - CLIP(p0 >> shift);
+        res[i+1] = smp[i+1] - CLIP(p1 >> shift);
+    }
+}
+
+static void FUNC(flac_lpc_encode_c)(int32_t *res, const int32_t *smp, int len,
+                                    int order, const int32_t *coefs, int shift)
+{
+    int i;
+    for (i = 0; i < order; i++)
+        res[i] = smp[i];
+#if CONFIG_SMALL
+    for (i = order; i < len; i += 2) {
+        int j;
+        int s  = smp[i];
+        sum_type p0 = 0, p1 = 0;
+        for (j = 0; j < order; j++) {
+            int c = coefs[j];
+            p1   += MUL(c, s);
+            s     = smp[i-j-1];
+            p0   += MUL(c, s);
+        }
+        res[i  ] = smp[i  ] - CLIP(p0 >> shift);
+        res[i+1] = smp[i+1] - CLIP(p1 >> shift);
+    }
+#else
+    switch (order) {
+    case  1: FUNC(lpc_encode_unrolled)(res, smp, len,     1, coefs, shift, 0); break;
+    case  2: FUNC(lpc_encode_unrolled)(res, smp, len,     2, coefs, shift, 0); break;
+    case  3: FUNC(lpc_encode_unrolled)(res, smp, len,     3, coefs, shift, 0); break;
+    case  4: FUNC(lpc_encode_unrolled)(res, smp, len,     4, coefs, shift, 0); break;
+    case  5: FUNC(lpc_encode_unrolled)(res, smp, len,     5, coefs, shift, 0); break;
+    case  6: FUNC(lpc_encode_unrolled)(res, smp, len,     6, coefs, shift, 0); break;
+    case  7: FUNC(lpc_encode_unrolled)(res, smp, len,     7, coefs, shift, 0); break;
+    case  8: FUNC(lpc_encode_unrolled)(res, smp, len,     8, coefs, shift, 0); break;
+    default: FUNC(lpc_encode_unrolled)(res, smp, len, order, coefs, shift, 1); break;
+    }
+#endif
+}