Add openmax dl routines for review. MUST NOT BE LANDED

third_party/openmax_dl/dl/sp/src/omxSP_FFTGetBufSize_C_SC16.c

+/*
+ *  Copyright (c) 2013 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ *
+ *  This file was originally licensed as follows. It has been
+ *  relicensed with permission from the copyright holders.
+ */
+
+/**
+ * 
+ * File Name:  omxSP_FFTGetBufSize_C_SC16.c
+ * OpenMAX DL: v1.0.2
+ * Last Modified Revision:   9468
+ * Last Modified Date:       Thu, 03 Jan 2008
+ * 
+ * (c) Copyright 2007-2008 ARM Limited. All Rights Reserved.
+ * 
+ * 
+ * Description:
+ * Compute the size of the specification structure required
+ */
+
+#include "dl/api/armOMX.h"
+#include "dl/api/omxtypes.h"
+#include "dl/sp/api/armSP.h"
+#include "dl/sp/api/omxSP.h"
+
+
+/**
+ * Function:  omxSP_FFTGetBufSize_C_SC16   (2.2.4.1.6)
+ *
+ * Description:
+ * These functions compute the size of the specification structure 
+ * required for the length 2^order complex FFT and IFFT functions. The function 
+ * <FFTGetBufSize_C_SC16> is used in conjunction with the 16-bit functions 
+ * <FFTFwd_CToC_SC16_Sfs> and <FFTInv_CToC_SC16_Sfs>. 
+ *
+ * Input Arguments:
+ *   
+ *   order - base-2 logarithm of the desired block length; valid in the range 
+ *            [0,12] 
+ *
+ * Output Arguments:
+ *   
+ *   pSize - pointer to the number of bytes required for the specification 
+ *            structure 
+ *
+ * Return Value:
+ *    
+ *    OMX_Sts_NoErr - no error 
+ *    
+ *
+ */
+
+
+
+OMXResult omxSP_FFTGetBufSize_C_SC16(
+     OMX_INT order,
+     OMX_INT *pSize)
+{
+    
+    OMX_INT     N,twiddleSize;
+    
+    /* Check for order zero */
+    if (order == 0)
+    {
+        *pSize = sizeof(ARMsFFTSpec_SC16);   
+        return OMX_Sts_NoErr;
+    }
+
+    
+    N = 1 << order;
+    
+    /*The max size of the twiddle table needed is 3N/4 for a radix-4 stage*/
+    twiddleSize = 3*N/4;
+
+    /* 2 pointers to store bitreversed array and twiddle factor array */
+    *pSize = sizeof(ARMsFFTSpec_SC16)
+        /* Twiddle factors  */
+           + sizeof(OMX_SC16) * twiddleSize
+        /* Ping Pong buffer   */   
+           + sizeof(OMX_SC16) * N
+           + 62 ;  /* Extra bytes to get 32 byte alignment of ptwiddle and pBuf */
+        
+    return OMX_Sts_NoErr;
+}
+
+/*****************************************************************************
+ *                              END OF FILE
+ *****************************************************************************/
+