clip2.c
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- /* ***** BEGIN LICENSE BLOCK *****
- * Source last modified: $Id: clip2.c,v 1.1.1.1.42.1 2004/07/09 01:56:22 hubbe Exp $
- *
- * Portions Copyright (c) 1995-2004 RealNetworks, Inc. All Rights Reserved.
- *
- * The contents of this file, and the files included with this file,
- * are subject to the current version of the RealNetworks Public
- * Source License (the "RPSL") available at
- * http://www.helixcommunity.org/content/rpsl unless you have licensed
- * the file under the current version of the RealNetworks Community
- * Source License (the "RCSL") available at
- * http://www.helixcommunity.org/content/rcsl, in which case the RCSL
- * will apply. You may also obtain the license terms directly from
- * RealNetworks. You may not use this file except in compliance with
- * the RPSL or, if you have a valid RCSL with RealNetworks applicable
- * to this file, the RCSL. Please see the applicable RPSL or RCSL for
- * the rights, obligations and limitations governing use of the
- * contents of the file.
- *
- * Alternatively, the contents of this file may be used under the
- * terms of the GNU General Public License Version 2 or later (the
- * "GPL") in which case the provisions of the GPL are applicable
- * instead of those above. If you wish to allow use of your version of
- * this file only under the terms of the GPL, and not to allow others
- * to use your version of this file under the terms of either the RPSL
- * or RCSL, indicate your decision by deleting the provisions above
- * and replace them with the notice and other provisions required by
- * the GPL. If you do not delete the provisions above, a recipient may
- * use your version of this file under the terms of any one of the
- * RPSL, the RCSL or the GPL.
- *
- * This file is part of the Helix DNA Technology. RealNetworks is the
- * developer of the Original Code and owns the copyrights in the
- * portions it created.
- *
- * This file, and the files included with this file, is distributed
- * and made available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY
- * KIND, EITHER EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS
- * ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES
- * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET
- * ENJOYMENT OR NON-INFRINGEMENT.
- *
- * Technology Compatibility Kit Test Suite(s) Location:
- * http://www.helixcommunity.org/content/tck
- *
- * Contributor(s):
- *
- * ***** END LICENSE BLOCK ***** */
- //#include <math.h>
- #include "dllindex.h"
- #include "h261defs.h"
- #include "h261func.h"
- #include "clip.h"
- #define FRACBITS 6 /* Fractional bits in IDCT computation */
- #define PIXEL_MIN 0
- #define PIXEL_MAX 255
- #define CLIPMARGIN 300
- #define CLIPMIN (PIXEL_MIN - CLIPMARGIN)
- #define CLIPMAX (PIXEL_MAX + CLIPMARGIN)
- extern PIXEL clip[(CLIPMAX-CLIPMIN+1)];
- extern void idct2sum_clip(PIXEL x[], int xdim, S32 idct_out[8][4], int idct_class)
- {
- int i, temp;
- #ifdef LITTLE_ENDIAN
- int hi_clip0, hi_clip1, hi_clip2, hi_clip3;
- int lo_clip0, lo_clip1, lo_clip2, lo_clip3;
- switch (idct_class)
- // DC only case
- {
- case DC_ONLY:
- {
- temp = idct_out[0][0];
- lo_clip0 = -CLIPMIN + ((temp << 16) >> (FRACBITS + 16));
- hi_clip0 = -CLIPMIN + (temp >> (FRACBITS + 16));
- for (i = 0; i < 8; i++)
- {
- x[i*xdim] = clip[x[i*xdim]+lo_clip0];
- x[i*xdim+1] = clip[x[i*xdim+1]+hi_clip0];
- x[i*xdim+2] = clip[x[i*xdim+2]+lo_clip0];
- x[i*xdim+3] = clip[x[i*xdim+3]+hi_clip0];
- x[i*xdim+7] = clip[x[i*xdim+7]+lo_clip0];
- x[i*xdim+6] = clip[x[i*xdim+6]+hi_clip0];
- x[i*xdim+5] = clip[x[i*xdim+5]+lo_clip0];
- x[i*xdim+4] = clip[x[i*xdim+4]+hi_clip0];
- }
- }
- break;
- // DC + 1 horizontal AC case
- case DC_AC_H:
- {
- temp = idct_out[0][0];
- lo_clip0 = -CLIPMIN + ((temp << 16) >> (FRACBITS + 16));
- hi_clip0 = -CLIPMIN + (temp >> (FRACBITS + 16));
- temp = idct_out[0][1];
- lo_clip1 = -CLIPMIN + ((temp << 16) >> (FRACBITS + 16));
- hi_clip1 = -CLIPMIN + (temp >> (FRACBITS + 16));
- temp = idct_out[0][2];
- lo_clip2 = -CLIPMIN + ((temp << 16) >> (FRACBITS + 16));
- hi_clip2 = -CLIPMIN + (temp >> (FRACBITS + 16));
- temp = idct_out[0][3];
- lo_clip3 = -CLIPMIN + ((temp << 16) >> (FRACBITS + 16));
- hi_clip3 = -CLIPMIN + (temp >> (FRACBITS + 16));
- for (i = 0; i < 8; i++)
- {
- x[i*xdim] = clip[x[i*xdim]+lo_clip0];
- x[i*xdim+1] = clip[x[i*xdim+1]+hi_clip0];
- x[i*xdim+2] = clip[x[i*xdim+2]+lo_clip1];
- x[i*xdim+3] = clip[x[i*xdim+3]+hi_clip1];
- x[i*xdim+7] = clip[x[i*xdim+7]+lo_clip2];
- x[i*xdim+6] = clip[x[i*xdim+6]+hi_clip2];
- x[i*xdim+5] = clip[x[i*xdim+5]+lo_clip3];
- x[i*xdim+4] = clip[x[i*xdim+4]+hi_clip3];
- }
- }
- break;
-
- case GENERAL:
- {
- for (i = 0; i < 8; i++)
- {
- temp = idct_out[i][0];
- x[i*xdim] = clip[x[i*xdim] -CLIPMIN + ((temp << 16) >> (FRACBITS + 16))];
- x[i*xdim+1] = clip[x[i*xdim+1] -CLIPMIN + (temp >> (FRACBITS + 16))];
- temp = idct_out[i][1];
- x[i*xdim+2] = clip[x[i*xdim+2] -CLIPMIN + ((temp << 16) >> (FRACBITS + 16))];
- x[i*xdim+3] = clip[x[i*xdim+3] -CLIPMIN + (temp >> (FRACBITS + 16))];
- temp = idct_out[i][2];
- x[i*xdim+7] = clip[x[i*xdim+7] -CLIPMIN + ((temp << 16) >> (FRACBITS + 16))];
- x[i*xdim+6] = clip[x[i*xdim+6] -CLIPMIN + (temp >> (FRACBITS + 16))];
- temp = idct_out[i][3];
- x[i*xdim+5] = clip[x[i*xdim+5] -CLIPMIN + ((temp << 16) >> (FRACBITS + 16))];
- x[i*xdim+4] = clip[x[i*xdim+4] -CLIPMIN + (temp >> (FRACBITS + 16))];
- }
- }
- break;
-
- default:
- break;
- }
- #else
- for (i = 0; i < 8; i++)
- {
- int j;
- // Notice the funky casts of idct_out, which needs to be treated
- // as an S16 [8][8].
- for (j = 0; j < 4; j++) {
- temp = ((S16 (*)[8]) idct_out)[i][j] >> FRACBITS;
- x[i*xdim+j] = clip[x[i*xdim+j] -CLIPMIN + temp];
- temp = ((S16 (*)[8]) idct_out)[i][j+4] >> FRACBITS;
- x[i*xdim+7-j] = clip[x[i*xdim+7-j] -CLIPMIN + temp];
- }
- }
- #endif
- }