Intel® Integrated Performance Primitives (Intel® IPP) Developer Guide and Reference

ID 790148
Date 3/22/2024
Public

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Document Table of Contents

EncodeLZO

Compresses input data, returns the length of the compressed data.

Syntax

IppStatus ippsEncodeLZO_8u (const Ipp8u* pSrc, Ipp32u srcLen, Ipp8u* pDst, Ipp32u* pDstLen, IppLZOState_8u* pLZOState);

Include Files

ippdc.h

Domain Dependencies

Headers: ippcore.h, ippvm.h, ipps.h

Libraries: ippcore.lib, ippvm.lib, ipps.lib

Parameters

pSrc

Pointer to the source buffer.

srcLen

Length of the source buffer.

pDst

Pointer to the destination buffer.

pDstLen

Pointer to the length of the destination buffer.

pLZOState

Pointer to the LZO state structure.

Description

This function performs compression of the source data pSrc according to the method specified in the LZO state structure pLZOState. It must be previously initialized by the function ippsEncodeLZOInit.

Compressed data are stored in the pDst, the pointer pDstLen points to the number of elements in this buffer.

Code example shows how the Intel IPP functions for the LZO compression can be used.

Return Values

ippStsNoErr

Indicates no error.

ippStsNullPtrErr

Indicates an error if one of the specified pointers is NULL.

Example

/*******************************************************************************
* Copyright 2017 Intel Corporation.
*
*
* This software and the related documents are Intel copyrighted materials, and your use of them is governed by
* the express license under which they were provided to you ('License'). Unless the License provides otherwise,
* you may not use, modify, copy, publish, distribute, disclose or transmit this software or the related
* documents without Intel's prior written permission.
* This software and the related documents are provided as is, with no express or implied warranties, other than
* those that are expressly stated in the License.
*******************************************************************************/

/*
 The example below shows how to use the functions:
        ippsEncodeLZOGetSize
        ippsEncodeLZO_8u
        ippsEncodeLZOInit_8u
        ippsDecodeLZO_8u
        ippsDecodeLZOSafe_8u
*/

#include <stdio.h>
#include <string.h>

#include <ipp/ippdc.h>      /* Data compression functions       */
#include <ipp/ipps.h>       /* Malloc/vector initialization function   */

/* Next two defines are created to simplify code reading and understanding          */
#define EXIT_MAIN       exitLine:                              /* Label for Exit    */
#define check_sts(st)   if((st) != ippStsNoErr) goto exitLine; /* Go to Exit if Intel(R) Integrated Performance Primitives (Intel(R) IPP) function returned status different from ippStsNoErr */

#define TEST_SIZE (1024 * 4)
#define DECOMPR_MAX (TEST_SIZE + 64)

int main(void)
{
    Ipp8u           *srcBuf = NULL, *comprBuf = NULL, *decomprBuf = NULL;
    IppStatus       st;
    int             i;
    Ipp32u          stateSize;
    IppLZOState_8u  *lzoState = NULL;
    Ipp32u          comprLen, decomprLen;

    /* Allocate buffers */
    srcBuf      = ippsMalloc_8u(TEST_SIZE);
    decomprBuf  = ippsMalloc_8u(DECOMPR_MAX);    /* Extra 64 bytes may be required
                                                       for non-safe decompression       */
    comprBuf    = ippsMalloc_8u(TEST_SIZE + TEST_SIZE/10);
    /* Initialize source buffer */
    check_sts(  st = ippsVectorJaehne_8u(srcBuf, TEST_SIZE, IPP_MAX_8U)         )
    for(i = 0; i < TEST_SIZE; i++)
        srcBuf[i] >>= 6;                                /* Decrease source data entropy */
    /* Allocate and initialize LZO structure */
    check_sts(  st = ippsEncodeLZOGetSize(IppLZO1XST, TEST_SIZE, &stateSize)    )
    lzoState = (IppLZOState_8u*)ippsMalloc_8u(stateSize);
    check_sts(  st = ippsEncodeLZOInit_8u(IppLZO1XST, TEST_SIZE, lzoState)      )
    /* LZO compress, decompress and compare */
    comprLen = (TEST_SIZE + TEST_SIZE/10);
    check_sts(  st = ippsEncodeLZO_8u(srcBuf, TEST_SIZE, comprBuf, &comprLen, lzoState)   )
    printf("LZO compress: %d bytes compressed into %d bytes\n", TEST_SIZE, (int)comprLen);
    decomprLen = DECOMPR_MAX;
    check_sts(  st = ippsDecodeLZO_8u(comprBuf, comprLen, decomprBuf, &decomprLen)    )
    if(decomprLen != TEST_SIZE || memcmp(decomprBuf, srcBuf, TEST_SIZE) != 0)
    {
        printf("Non-safe decompress failed!\n");
        st = ippStsErr;
        goto exitLine;
    }
    else
        printf("Non-safe decompress verified.\n");
    /* Decompress using safe function */
    ippsZero_8u(decomprBuf, DECOMPR_MAX);
    decomprLen = TEST_SIZE;                         /* Can specify exact size */
    check_sts(  st = ippsDecodeLZOSafe_8u(comprBuf, comprLen, decomprBuf, &decomprLen)  )
    if(decomprLen != TEST_SIZE || memcmp(decomprBuf, srcBuf, TEST_SIZE) != 0)
    {
        printf("Safe decompress failed!\n");
        st = ippStsErr;
        goto exitLine;
    }
    else
        printf("Safe decompress verified.\n");

EXIT_MAIN
    ippsFree(srcBuf);
    ippsFree(decomprBuf);
    ippsFree(comprBuf);
    ippsFree(lzoState);
    return (int)st;
}