avcodec/dsd_tablegen: Merge header into dsd.c

Since b492fbcc6e87094804fdf71308dc500976c6b165, the DSD tables are
always initialized at runtime, so merge the dsd_tablegen.h header
into dsd.c.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

1 files changed, 43 insertions, 1 deletions

diff --git a/libavcodec/dsd.c b/libavcodec/dsd.c
index 95aab61ea4..c18e20436a 100644
--- a/libavcodec/dsd.c
+++ b/libavcodec/dsd.c
@@ -25,9 +25,51 @@
 #include "libavcodec/internal.h"
 #include "libavcodec/mathops.h"
 #include "avcodec.h"
-#include "dsd_tablegen.h"
 #include "dsd.h"
 
+#define CTABLES ((HTAPS + 7) / 8) /** number of "8 MACs" lookup tables */
+
+/*
+ * Properties of this 96-tap lowpass filter when applied on a signal
+ * with sampling rate of 44100*64 Hz:
+ *
+ * () has a delay of 17 microseconds.
+ *
+ * () flat response up to 48 kHz
+ *
+ * () if you downsample afterwards by a factor of 8, the
+ *    spectrum below 70 kHz is practically alias-free.
+ *
+ * () stopband rejection is about 160 dB
+ *
+ * The coefficient tables ("ctables") take only 6 Kibi Bytes and
+ * should fit into a modern processor's fast cache.
+ */
+
+/**
+ * The 2nd half (48 coeffs) of a 96-tap symmetric lowpass filter
+ */
+static const double htaps[HTAPS] = {
+     0.09950731974056658,    0.09562845727714668,    0.08819647126516944,
+     0.07782552527068175,    0.06534876523171299,    0.05172629311427257,
+     0.0379429484910187,     0.02490921351762261,    0.0133774746265897,
+     0.003883043418804416,  -0.003284703416210726,  -0.008080250212687497,
+    -0.01067241812471033,   -0.01139427235000863,   -0.0106813877974587,
+    -0.009007905078766049,  -0.006828859761015335,  -0.004535184322001496,
+    -0.002425035959059578,  -0.0006922187080790708,  0.0005700762133516592,
+     0.001353838005269448,   0.001713709169690937,   0.001742046839472948,
+     0.001545601648013235,   0.001226696225277855,   0.0008704322683580222,
+     0.0005381636200535649,  0.000266446345425276,   7.002968738383528e-05,
+    -5.279407053811266e-05, -0.0001140625650874684, -0.0001304796361231895,
+    -0.0001189970287491285, -9.396247155265073e-05, -6.577634378272832e-05,
+    -4.07492895872535e-05,  -2.17407957554587e-05,  -9.163058931391722e-06,
+    -2.017460145032201e-06,  1.249721855219005e-06,  2.166655190537392e-06,
+     1.930520892991082e-06,  1.319400334374195e-06,  7.410039764949091e-07,
+     3.423230509967409e-07,  1.244182214744588e-07,  3.130441005359396e-08
+};
+
+static float ctables[CTABLES][256];
+
 static av_cold void dsd_ctables_tableinit(void)
 {
     int t, e, m, sign;