SIMD-friendly variant of SBC encoder analysis filter

Added SIMD-friendly C implementation of SBC analysis filter (the
structure of code had to be changed a bit and constants in the
tables reordered). This code can be used as a reference for
developing platform specific SIMD optimizations. These functions
are put into a new file 'sbc_primitives.c', which is going to
contain all the basic stuff for SBC codec.

1 files changed, 52 insertions, 0 deletions

diff --git a/sbc/sbc_primitives.h b/sbc/sbc_primitives.h
new file mode 100644
index 00000000..ca1ec277
--- /dev/null
+++ b/sbc/sbc_primitives.h
@@ -0,0 +1,52 @@
+/*
+ *
+ *  Bluetooth low-complexity, subband codec (SBC) library
+ *
+ *  Copyright (C) 2004-2009  Marcel Holtmann <marcel@holtmann.org>
+ *  Copyright (C) 2004-2005  Henryk Ploetz <henryk@ploetzli.ch>
+ *  Copyright (C) 2005-2006  Brad Midgley <bmidgley@xmission.com>
+ *
+ *
+ *  This library 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.
+ *
+ *  This library 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 this library; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ */
+
+#ifndef __SBC_PRIMITIVES_H
+#define __SBC_PRIMITIVES_H
+
+#define SCALE_OUT_BITS 15
+
+struct sbc_encoder_state {
+	int subbands;
+	int position[2];
+	int16_t X[2][256];
+	/* Polyphase analysis filter for 4 subbands configuration,
+	   it handles 4 blocks at once */
+	void (*sbc_analyze_4b_4s)(int16_t *pcm, int16_t *x,
+				  int32_t *out, int out_stride);
+	/* Polyphase analysis filter for 8 subbands configuration,
+	   it handles 4 blocks at once */
+	void (*sbc_analyze_4b_8s)(int16_t *pcm, int16_t *x,
+				  int32_t *out, int out_stride);
+};
+
+/*
+ * Initialize pointers to the functions which are the basic "building bricks"
+ * of SBC codec. Best implementation is selected based on target CPU
+ * capabilities.
+ */
+void sbc_init_primitives(struct sbc_encoder_state *encoder_state);
+
+#endif