;* ======================================================================== *;
;* TEXAS INSTRUMENTS, INC. *;
;* *;
;* DSPLIB DSP Signal Processing Library *;
;* *;
;* Release: Version 1.02 *;
;* CVS Revision: 1.3 Fri Mar 22 01:53:40 2002 (UTC) *;
;* Snapshot date: 18-Apr-2002 *;
;* *;
;* This library contains proprietary intellectual property of Texas *;
;* Instruments, Inc. The library and its source code are protected by *;
;* various copyrights, and portions may also be protected by patents or *;
;* other legal protections. *;
;* *;
;* This software is licensed for use with Texas Instruments TMS320 *;
;* family DSPs. This license was provided to you prior to installing *;
;* the software. You may review this license by consulting the file *;
;* TI_license.PDF which accompanies the files in this library. *;
;* ------------------------------------------------------------------------ *;
;* Copyright (C) 2002 Texas Instruments, Incorporated. *;
;* All Rights Reserved. *;
;* ======================================================================== *;
* ========================================================================= *
* *
* TEXAS INSTRUMENTS, INC. *
* *
* NAME *
* DSP_mat_trans *
* *
* REVISION DATE *
* 27-Jul-2001 *
* *
* USAGE *
* This routine is C-callable and can be called as: *
* *
* void DSP_mat_trans *
* ( *
* const short *restrict x, *
* short rows, *
* short columns, *
* short *restrict r *
* ); *
* *
* x[rows*columns] : Pointer to input matrix. In-place *
* processing not allowed. *
* rows : Number of rows in input matrix *
* columns : Number of columns in input matrix *
* r[columns*rows] : Pointer to output matrix. *
* *
* DESCRIPTION *
* The program transposes a matrix of 16-bit values with dimension *
* rows x columns, i.e. the value of an element in the output matrix *
* is equal to the value of the element from the input matrix with *
* switched coordinates. *
* *
* C CODE *
* void DSP_mat_trans(short *x, short rows, short columns, short *r) *
* { *
* short i,j; *
* *
* for(i = 0; i < columns; i++) *
* for(j = 0; j < rows; j++) *
* r[i * rows + j] = x[i + columns * j]; *
* } *
* *
* TECHNIQUES *
* The kernel of the code combines two loops in one. As the program *
* goes accross the input matrix (always just incrementing pointer), *
* it must go down the output matrix (addition to pointer). After *
* each write it checks to see if the output pointer has reached the *
* end of the column. If so, it redirects the output pointer to the *
* beginning of the next column. This technique is good for most size *
* matrices, but for very large matrices, a more efficient technique *
* would use two loops so that the inner one could accomodate *
* more elements per cycle. *
* *
* ASSUMPTIONS *
* Matrices have 16-bit elements *
* *
* MEMORY NOTE *
* This code is ENDIAN NEUTRAL. *
* No memory bank hits occur. *
* *
* CYCLES *
* 6 * floor[rows * columns / 3] + 11 *
* *
* For rows = 69, columns = 17: 2357 cycles *
* *
* CODESIZE *
* 192 bytes *
* *
* ------------------------------------------------------------------------- *
* Copyright (c) 2002 Texas Instruments, Incorporated. *
* All Rights Reserved. *
* ========================================================================= *
.global _DSP_mat_trans
* ========================================================================= *
* End of file: dsp_mat_trans.h62 *
* ------------------------------------------------------------------------- *
* Copyright (c) 2002 Texas Instruments, Incorporated. *
* All Rights Reserved. *
* ========================================================================= *