1 files changed, 66 insertions, 0 deletions
diff --git a/include/xtract/xtract_stateful.h b/include/xtract/xtract_stateful.h
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+++ b/include/xtract/xtract_stateful.h
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+/*
+ * Copyright (C) 2012 Jamie Bullock
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+/** \file xtract_stateful.h: declares functions that extract features that require stateful data to be retained between frames */
+#ifndef XTRACT_STATEFUL_H
+#define XTRACT_STATEFUL_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+	
+/**
+ * \defgroup stateful feature extraction functions and data structures
+ *
+ * Functions that extract a feature over multiple frames
+ *
+ * @{
+ */
+
+    
+#include <stdint.h>
+#include <string.h>
+
+typedef struct xtract_last_n_state_ xtract_last_n_state;
+        
+xtract_last_n_state *xtract_last_n_state_new(size_t capacity);
+void xtract_last_n_state_delete(xtract_last_n_state *last_n_state);
+
+    
+/**
+ *  Write a vector of the last N input values to `result`
+ *
+ *  @param state  a pointer to an xtract_peak_picker_state struct as allocated by xtract_peak_picker_state_new()
+ *  @param data   a pointer to a double representing the current input value
+ *  @param N      an integer representing 'N' the number of values to be written to *result
+ *  @param argv   a pointer to NULL
+ *  @param result a pointer to an array of doubles representing the last N values, where the nth value is the current one. The array must have been allocated to size N elements and initialised by the caller
+ *
+ */
+int xtract_last_n(const xtract_last_n_state *state, const double *data, const int N, const void *argv, double *result);
+    
+#ifdef __cplusplus
+}
+#endif
+
+#endif