bits.c

Zoran V966 DVD 解码 Soc芯片的源程序

/*
// $Header: /I76/I76_Common/I76_Reference/Playcore/Nav_Clips/AviDrm/libDrmDecrypt/Bits.c 2     2/15/04 7:41p Lotan $
// Copyright (c) DivXNetworks, Inc. http://www.divxnetworks.com
// All rights reserved.
//
// This software is the confidential and proprietary information of DivxNetworks
// Inc. ("Confidential Information").  You shall not disclose such Confidential
// Information and shall use it only in accordance with the terms of the license
// agreement you entered into with DivXNetworks, Inc.
*/
#include "Playcore\Nav_Clips\AviDrm\libDrmDecrypt\Bits.h"

#ifdef AVI_DRM_SUPPORT

#include <stdio.h>  /* sprintf */
#include <string.h> /* strcpy */
#include <limits.h> /* CHAR_BIT */
#include <stdlib.h> /* atoi */

void assign(uint8_t *a, uint8_t *b, uint8_t direction) /* Used to make packLogic generic. */
{
    if (direction == A_BECOMES_B)
    {
        a[0] = b[0];
    }
    if (direction == B_BECOMES_A)
    {
        b[0] = a[0];
    }
}

void quarterByteSwap(uint8_t *a, uint8_t *b, uint8_t position)
{
	
	uint8_t mask;

	switch (position)
	{
	case 0:
		mask = 0x3F;
		break;
	case 1:
		mask = 0xCF;
		break;
	case 2:
		mask = 0xF3;
		break;
	case 3:
		mask = 0xFC;
		break;
	default:
		mask = 0x3F;

	}

	maskSwap(a, b, mask);
}

void halfByteSwap(uint8_t *a, uint8_t *b, uint8_t position)
{
	
	uint8_t mask;

	switch (position)
	{
	case 0:
		mask = 0x0F;
		break;
	case 1:
		mask = 0xF0;
		break;
	default:
		mask = 0x0F;

	}

	maskSwap(a, b, mask);
}

void maskSwap(uint8_t *a, uint8_t *b, uint8_t mask)
{
	uint8_t aResult;
	uint8_t bResult;

	aResult = (*a & mask) | (*b & ~mask);
	bResult = (*b & mask) | (*a & ~mask);

    *a = aResult;
	*b = bResult;
}

uint16_t pack(uint8_t low, uint8_t hi)
{
    uint16_t result = hi;
    result = (result << 8) | low;
    return result;
}

void unpack(uint16_t whole, uint8_t *hi, uint8_t *low)
{
    *hi = (whole & 0xff00) >> 8;
    *low = whole & 0xff;
}

uint8_t getByteLoopSizeFromBits(uint8_t sizeInBits)
{
    uint8_t result;
    
    result = sizeInBits / CHAR_BIT;
    if ((sizeInBits % CHAR_BIT) > 0)
    {
        result++;
    }
    
    return result;
}


#endif // AVI_DRM_SUPPORT