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author | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2006-08-19 03:12:28 +0000 |
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committer | giraffedata <giraffedata@9d0c8265-081b-0410-96cb-a4ca84ce46f8> | 2006-08-19 03:12:28 +0000 |
commit | 1fd361a1ea06e44286c213ca1f814f49306fdc43 (patch) | |
tree | 64c8c96cf54d8718847339a403e5e67b922e8c3f /converter/ppm/ppmtompeg/headers/dct.h | |
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Create Subversion repository
git-svn-id: http://svn.code.sf.net/p/netpbm/code/trunk@1 9d0c8265-081b-0410-96cb-a4ca84ce46f8
Diffstat (limited to 'converter/ppm/ppmtompeg/headers/dct.h')
-rw-r--r-- | converter/ppm/ppmtompeg/headers/dct.h | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/converter/ppm/ppmtompeg/headers/dct.h b/converter/ppm/ppmtompeg/headers/dct.h new file mode 100644 index 00000000..e024b6c1 --- /dev/null +++ b/converter/ppm/ppmtompeg/headers/dct.h @@ -0,0 +1,79 @@ +/*===========================================================================* + * dct.h * + * * + * DCT procedures * + * * + *===========================================================================*/ + +/* + * Copyright (c) 1995 The Regents of the University of California. + * All rights reserved. + * + * Permission to use, copy, modify, and distribute this software and its + * documentation for any purpose, without fee, and without written agreement is + * hereby granted, provided that the above copyright notice and the following + * two paragraphs appear in all copies of this software. + * + * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR + * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT + * OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF + * CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, + * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS + * ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO + * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. + */ + + +#ifndef DCT_INCLUDED +#define DCT_INCLUDED + + +#include "ansi.h" + + + +#define DCTSIZE 8 /* you really don't want to change this */ +#define DCTSIZE_SQ 64 /* you really don't want to change this */ + +#define DCTSIZE2 64 +typedef short DCTELEM; +typedef DCTELEM DCTBLOCK[DCTSIZE2]; +typedef DCTELEM DCTBLOCK_2D[DCTSIZE][DCTSIZE]; + + +/* + * from mfwddct.c: + */ +extern void mp_fwd_dct_block2 _ANSI_ARGS_((DCTBLOCK_2D src, DCTBLOCK_2D dest)); + +/* jrevdct.c */ +extern void init_pre_idct _ANSI_ARGS_((void )); +extern void mpeg_jrevdct _ANSI_ARGS_((DCTBLOCK data )); + + +/* We assume that right shift corresponds to signed division by 2 with + * rounding towards minus infinity. This is correct for typical "arithmetic + * shift" instructions that shift in copies of the sign bit. But some + * C compilers implement >> with an unsigned shift. For these machines you + * must define RIGHT_SHIFT_IS_UNSIGNED. + * RIGHT_SHIFT provides a proper signed right shift of an int32 quantity. + * It is only applied with constant shift counts. SHIFT_TEMPS must be + * included in the variables of any routine using RIGHT_SHIFT. + */ + +#ifdef RIGHT_SHIFT_IS_UNSIGNED +#define SHIFT_TEMPS int32 shift_temp; +#define RIGHT_SHIFT(x,shft) \ + ((shift_temp = (x)) < 0 ? \ + (shift_temp >> (shft)) | ((~((int32) 0)) << (32-(shft))) : \ + (shift_temp >> (shft))) +#else +#define SHIFT_TEMPS +#define RIGHT_SHIFT(x,shft) ((x) >> (shft)) +#endif + + +#endif /* DCT_INCLUDED */ |