lavr: resampling: add support for s32p, fltp, and dblp internal sample formats

Based partially on implementation by Michael Niedermayer <michaelni@gmx.at> in
libswresample in FFmpeg. See commits:
7f1ae79d38c4edba9dbd31d7bf797e525298ac55
24ab1abfb6d55bf330022df4b10d7aec80b3f116

1 files changed, 102 insertions, 0 deletions

diff --git a/libavresample/resample_template.c b/libavresample/resample_template.c
new file mode 100644
index 0000000000..5b0fbecdf5
--- /dev/null
+++ b/libavresample/resample_template.c
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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
+ */
+
+#if defined(CONFIG_RESAMPLE_DBL)
+#define SET_TYPE(func)  func ## _dbl
+#define FELEM         double
+#define FELEM2        double
+#define FELEML        double
+#define OUT(d, v) d = v
+#define DBL_TO_FELEM(d, v) d = v
+#elif defined(CONFIG_RESAMPLE_FLT)
+#define SET_TYPE(func)  func ## _flt
+#define FELEM         float
+#define FELEM2        float
+#define FELEML        float
+#define OUT(d, v) d = v
+#define DBL_TO_FELEM(d, v) d = v
+#elif defined(CONFIG_RESAMPLE_S32)
+#define SET_TYPE(func)  func ## _s32
+#define FELEM         int32_t
+#define FELEM2        int64_t
+#define FELEML        int64_t
+#define OUT(d, v) d = av_clipl_int32((v + (1 << 29)) >> 30)
+#define DBL_TO_FELEM(d, v) d = av_clipl_int32(llrint(v * (1 << 30)));
+#else
+#define SET_TYPE(func)  func ## _s16
+#define FELEM         int16_t
+#define FELEM2        int32_t
+#define FELEML        int64_t
+#define OUT(d, v) d = av_clip_int16((v + (1 << 14)) >> 15)
+#define DBL_TO_FELEM(d, v) d = av_clip_int16(lrint(v * (1 << 15)))
+#endif
+
+static void SET_TYPE(resample_one)(ResampleContext *c, int no_filter,
+                                   void *dst0, int dst_index, const void *src0,
+                                   int src_size, int index, int frac)
+{
+    FELEM *dst = dst0;
+    const FELEM *src = src0;
+
+    if (no_filter) {
+        dst[dst_index] = src[index];
+    } else {
+        int i;
+        int sample_index = index >> c->phase_shift;
+        FELEM2 val = 0;
+        FELEM *filter = ((FELEM *)c->filter_bank) +
+                        c->filter_length * (index & c->phase_mask);
+
+        if (sample_index < 0) {
+            for (i = 0; i < c->filter_length; i++)
+                val += src[FFABS(sample_index + i) % src_size] *
+                       (FELEM2)filter[i];
+        } else if (c->linear) {
+            FELEM2 v2 = 0;
+            for (i = 0; i < c->filter_length; i++) {
+                val += src[abs(sample_index + i)] * (FELEM2)filter[i];
+                v2  += src[abs(sample_index + i)] * (FELEM2)filter[i + c->filter_length];
+            }
+            val += (v2 - val) * (FELEML)frac / c->src_incr;
+        } else {
+            for (i = 0; i < c->filter_length; i++)
+                val += src[sample_index + i] * (FELEM2)filter[i];
+        }
+
+        OUT(dst[dst_index], val);
+    }
+}
+
+static void SET_TYPE(set_filter)(void *filter0, double *tab, int phase,
+                                 int tap_count)
+{
+    int i;
+    FELEM *filter = ((FELEM *)filter0) + phase * tap_count;
+    for (i = 0; i < tap_count; i++) {
+        DBL_TO_FELEM(filter[i], tab[i]);
+    }
+}
+
+#undef SET_TYPE
+#undef FELEM
+#undef FELEM2
+#undef FELEML
+#undef OUT
+#undef DBL_TO_FELEM