EncodeLZO
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 isNULL.
Example
/*******************************************************************************
* Copyright 2017-2021 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 <ippdc.h> /* Data compression functions */
#include <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 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;
}