多媒体编程

开发平台：
Visual C++

GSHash.cpp：源码内容
							/* 
 *	Copyright (C) 2003-2005 Gabest
 *	http://www.gabest.org
 *
 *  This Program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *   
 *  This Program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *  GNU General Public License for more details.
 *   
 *  You should have received a copy of the GNU General Public License
 *  along with GNU Make; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. 
 *  http://www.gnu.org/copyleft/gpl.html
 *
 */
#include "stdafx.h"
static const DWORD s_crctable[256] = 
{
	0x00000000l, 0x90910101l, 0x91210201l, 0x01b00300l,
	0x92410401l, 0x02d00500l, 0x03600600l, 0x93f10701l,
	0x94810801l, 0x04100900l, 0x05a00a00l, 0x95310b01l,
	0x06c00c00l, 0x96510d01l, 0x97e10e01l, 0x07700f00l,
	0x99011001l, 0x09901100l, 0x08201200l, 0x98b11301l,
	0x0b401400l, 0x9bd11501l, 0x9a611601l, 0x0af01700l,
	0x0d801800l, 0x9d111901l, 0x9ca11a01l, 0x0c301b00l,
	0x9fc11c01l, 0x0f501d00l, 0x0ee01e00l, 0x9e711f01l,
	0x82012001l, 0x12902100l, 0x13202200l, 0x83b12301l,
	0x10402400l, 0x80d12501l, 0x81612601l, 0x11f02700l,
	0x16802800l, 0x86112901l, 0x87a12a01l, 0x17302b00l,
	0x84c12c01l, 0x14502d00l, 0x15e02e00l, 0x85712f01l,
	0x1b003000l, 0x8b913101l, 0x8a213201l, 0x1ab03300l,
	0x89413401l, 0x19d03500l, 0x18603600l, 0x88f13701l,
	0x8f813801l, 0x1f103900l, 0x1ea03a00l, 0x8e313b01l,
	0x1dc03c00l, 0x8d513d01l, 0x8ce13e01l, 0x1c703f00l,
	0xb4014001l, 0x24904100l, 0x25204200l, 0xb5b14301l,
	0x26404400l, 0xb6d14501l, 0xb7614601l, 0x27f04700l,
	0x20804800l, 0xb0114901l, 0xb1a14a01l, 0x21304b00l,
	0xb2c14c01l, 0x22504d00l, 0x23e04e00l, 0xb3714f01l,
	0x2d005000l, 0xbd915101l, 0xbc215201l, 0x2cb05300l,
	0xbf415401l, 0x2fd05500l, 0x2e605600l, 0xbef15701l,
	0xb9815801l, 0x29105900l, 0x28a05a00l, 0xb8315b01l,
	0x2bc05c00l, 0xbb515d01l, 0xbae15e01l, 0x2a705f00l,
	0x36006000l, 0xa6916101l, 0xa7216201l, 0x37b06300l,
	0xa4416401l, 0x34d06500l, 0x35606600l, 0xa5f16701l,
	0xa2816801l, 0x32106900l, 0x33a06a00l, 0xa3316b01l,
	0x30c06c00l, 0xa0516d01l, 0xa1e16e01l, 0x31706f00l,
	0xaf017001l, 0x3f907100l, 0x3e207200l, 0xaeb17301l,
	0x3d407400l, 0xadd17501l, 0xac617601l, 0x3cf07700l,
	0x3b807800l, 0xab117901l, 0xaaa17a01l, 0x3a307b00l,
	0xa9c17c01l, 0x39507d00l, 0x38e07e00l, 0xa8717f01l,
	0xd8018001l, 0x48908100l, 0x49208200l, 0xd9b18301l,
	0x4a408400l, 0xdad18501l, 0xdb618601l, 0x4bf08700l,
	0x4c808800l, 0xdc118901l, 0xdda18a01l, 0x4d308b00l,
	0xdec18c01l, 0x4e508d00l, 0x4fe08e00l, 0xdf718f01l,
	0x41009000l, 0xd1919101l, 0xd0219201l, 0x40b09300l,
	0xd3419401l, 0x43d09500l, 0x42609600l, 0xd2f19701l,
	0xd5819801l, 0x45109900l, 0x44a09a00l, 0xd4319b01l,
	0x47c09c00l, 0xd7519d01l, 0xd6e19e01l, 0x46709f00l,
	0x5a00a000l, 0xca91a101l, 0xcb21a201l, 0x5bb0a300l,
	0xc841a401l, 0x58d0a500l, 0x5960a600l, 0xc9f1a701l,
	0xce81a801l, 0x5e10a900l, 0x5fa0aa00l, 0xcf31ab01l,
	0x5cc0ac00l, 0xcc51ad01l, 0xcde1ae01l, 0x5d70af00l,
	0xc301b001l, 0x5390b100l, 0x5220b200l, 0xc2b1b301l,
	0x5140b400l, 0xc1d1b501l, 0xc061b601l, 0x50f0b700l,
	0x5780b800l, 0xc711b901l, 0xc6a1ba01l, 0x5630bb00l,
	0xc5c1bc01l, 0x5550bd00l, 0x54e0be00l, 0xc471bf01l,
	0x6c00c000l, 0xfc91c101l, 0xfd21c201l, 0x6db0c300l,
	0xfe41c401l, 0x6ed0c500l, 0x6f60c600l, 0xfff1c701l,
	0xf881c801l, 0x6810c900l, 0x69a0ca00l, 0xf931cb01l,
	0x6ac0cc00l, 0xfa51cd01l, 0xfbe1ce01l, 0x6b70cf00l,
	0xf501d001l, 0x6590d100l, 0x6420d200l, 0xf4b1d301l,
	0x6740d400l, 0xf7d1d501l, 0xf661d601l, 0x66f0d700l,
	0x6180d800l, 0xf111d901l, 0xf0a1da01l, 0x6030db00l,
	0xf3c1dc01l, 0x6350dd00l, 0x62e0de00l, 0xf271df01l,
	0xee01e001l, 0x7e90e100l, 0x7f20e200l, 0xefb1e301l,
	0x7c40e400l, 0xecd1e501l, 0xed61e601l, 0x7df0e700l,
	0x7a80e800l, 0xea11e901l, 0xeba1ea01l, 0x7b30eb00l,
	0xe8c1ec01l, 0x7850ed00l, 0x79e0ee00l, 0xe971ef01l,
	0x7700f000l, 0xe791f101l, 0xe621f201l, 0x76b0f300l,
	0xe541f401l, 0x75d0f500l, 0x7460f600l, 0xe4f1f701l,
	0xe381f801l, 0x7310f900l, 0x72a0fa00l, 0xe231fb01l,
	0x71c0fc00l, 0xe151fd01l, 0xe0e1fe01l, 0x7070ff00l
};
DWORD hash_crc(const CRect& r, int pitch, BYTE* p)
{
	if(r.Width() == 0) {ASSERT(0); return 0;}
	DWORD hash = ~0;
	for(int j = r.top; j < r.bottom; j++, p += pitch)
	{
		for(int i = r.left, x = 0; i < r.right; i++, x += 4)
		{
			hash = s_crctable[(hash ^ p[x+0]) & 0xff] ^ (hash >> 8); 
			hash = s_crctable[(hash ^ p[x+1]) & 0xff] ^ (hash >> 8); 
			hash = s_crctable[(hash ^ p[x+2]) & 0xff] ^ (hash >> 8); 
			hash = s_crctable[(hash ^ p[x+3]) & 0xff] ^ (hash >> 8); 
		}
	}
	return hash;
}
#define MOD_ADLER 65521
DWORD hash_adler(const CRect& r, int pitch, BYTE* p)
{
	if(r.Width() == 0) {ASSERT(0); return 0;}
	DWORD a = 1, b = 0;
	for(int j = r.top; j < r.bottom; j++, p += pitch)
	{
		for(int i = r.left, x = 0; i < r.right; i++, x += 4)
		{
			a += p[x+0]; b += a;
			a += p[x+1]; b += a;
			a += p[x+2]; b += a;
			a += p[x+3]; b += a;
		}
		a = (a & 0xffff) + (a >> 16) * (65536 - MOD_ADLER);
		b = (b & 0xffff) + (b >> 16) * (65536 - MOD_ADLER);
	}
	// a = (a & 0xffff) + (a >> 16) * (65536 - MOD_ADLER);
	if(a >= MOD_ADLER) a -= MOD_ADLER;
	b = (b & 0xffff) + (b >> 16) * (65536 - MOD_ADLER);
	if(b >= MOD_ADLER) b -= MOD_ADLER;
	return b << 16 | a;
}
DWORD hash_checksum(const CRect& r, int pitch, BYTE* p)
{
	if(r.Width() == 0) {ASSERT(0); return 0;}
	DWORD hash = 0;
#if defined(_M_AMD64) || _M_IX86_FP >= 2
	if(r.Width() >= 4 && !((DWORD_PTR)p & 0xf) && !(pitch & 0xf))
	{
		__m128i hash128 = _mm_setzero_si128();
		for(int j = r.top; j < r.bottom; j++, p += pitch)
		{
			hash128 = _mm_add_epi32(hash128, _mm_set1_epi32(j));
			for(int i = r.left, x = 0; i < r.right; i += 4, x++)
			{
				hash128 = _mm_shuffle_epi32(hash128, 0x93);
				////hash128 = _mm_shufflelo_epi16(hash128, 0x93);
				//hash128 = _mm_shufflehi_epi16(hash128, 0x93);
				hash128 = _mm_add_epi32(hash128, _mm_load_si128(&((__m128i*)p)[x]));
			}
		}
		hash128 = _mm_add_epi32(hash128, _mm_srli_si128(hash128, 8));
		hash128 = _mm_add_epi32(hash128, _mm_srli_si128(hash128, 4));
		hash += _mm_cvtsi128_si32(hash128);
	}
	else 
#endif
	{
		for(int j = r.top; j < r.bottom; j++, p += pitch)
		{
			hash += j;
			for(int i = r.left, x = 0; i < r.right; i++, x++)
			{
				hash += ((DWORD*)p)[x];
			}
		}
	}
	return hash;
}

						