Compressed LZO File Format - Revision history

Lou Montana: Text replacement - "\[\[Category:BIS( |_)File( |_)Formats\]\]" to "Category:Real Virtuality File Formats"

2025-05-08T11:27:10Z

Text replacement - "\[\[Category:BIS( |_)File( |_)Formats\]\]" to "Category:Real Virtuality File Formats"

← Older revision		Revision as of 13:27, 8 May 2025
Line 225:		Line 225:


	[[Category:~~BIS~~ File Formats]]		[[Category:Real Virtuality File Formats]]
	{{GameCategory\|arma1\|File Formats}}		{{GameCategory\|arma1\|File Formats}}

Lou Montana: Text replacement - "y[ _]\|[ _](arma[0-9]+)[ _]*\|[ _]+" to "y|$1|"

2021-06-22T12:11:35Z

Text replacement - "y[ _]*\|[ _]*(arma[0-9]+)[ _]*\|[ _]+" to "y|$1|"

← Older revision		Revision as of 14:11, 22 June 2021
Line 226:		Line 226:

	[[Category:BIS File Formats]]		[[Category:BIS File Formats]]
	{{GameCategory\|arma1\| File Formats}}		{{GameCategory\|arma1\|File Formats}}

Lou Montana: Text replacement - "{{unsupported-doc}}" to "{{Feature|UnsupportedDoc}}"

2021-02-01T13:57:30Z

Text replacement - "{{unsupported-doc}}" to "{{Feature|UnsupportedDoc}}"

← Older revision		Revision as of 15:57, 1 February 2021
Line 1:		Line 1:
	{{~~unsupported-doc~~}}		{{Feature\|UnsupportedDoc}}
	This is LZO as defined by oberhumer - http://www.oberhumer.com/opensource/lzo/		This is LZO as defined by oberhumer - http://www.oberhumer.com/opensource/lzo/

Lou Montana: Text replacement - "\[\[[Cc]ategory:ArmA:[ _]?([^|]+)\]\]" to "{{GameCategory|arma1|$1}}"

2021-01-06T13:00:09Z

Text replacement - "\[\[[Cc]ategory:ArmA:[ _]?([^|]+)\]\]" to "{{GameCategory|arma1|$1}}"

← Older revision		Revision as of 15:00, 6 January 2021
Line 226:		Line 226:

	[[Category:BIS File Formats]]		[[Category:BIS File Formats]]
	~~[[Category:ArmA:~~ File Formats]]		{{GameCategory\|arma1\| File Formats}}

Lou Montana: Some wiki formatting

2020-06-01T11:29:57Z

Some wiki formatting

Show changes

Mikero at 09:14, 9 May 2010

2010-05-09T09:14:52Z

← Older revision		Revision as of 11:14, 9 May 2010
Line 1:		Line 1:
			{{unsupported-doc}}
	===LZO===		===LZO===
	This is LZO as defined by oberhumer		This is LZO as defined by oberhumer

Mikero at 09:12, 9 May 2010

2010-05-09T09:12:58Z

New page

===LZO===
This is LZO as defined by oberhumer

http://www.oberhumer.com/opensource/lzo/

there are 3 sources to the lzo code

minilzo (on above site)
lzo version 2 (ditto)
lzo version 1 http://sourceforge.net/project/showfiles.php?group_id=102072&package_id=110218&release_id=221836

<pre><nowiki>

// some of the includes are for compression only (not listed here)

int lzo::lzo1x_decompress_safe ( const byte* in , byte* out, unsigned OutLen)

// returns length of consumed input bytes ,or, negative status
// Outlen is the desired output 'block size' this function will return neg status if the output buffer is not completely filled

// example call

byte Array=(byte)malloc(Outlen); // no zero clearing is necessary
int status_or_len=lzo->lzo1x_decompress_safe (input, Array,OutLen);#include "minilzo.h"

#include <limits.h>
#include <stddef.h>
#include <limits.h>
#include <stddef.h>
#include <string.h>
#include <malloc.h>

#define assert(val) if (!(val)) return LZO_E_ERROR
#define M2_MAX_OFFSET 0x0800

#define NEED_OP(x) if ((unsigned)(op_end - op) < (unsigned)(x)) return LZO_E_OUTPUT_OVERRUN;
#define TEST_LB() if (m_pos < out || m_pos >= op) return LZO_E_LOOKBEHIND_OVERRUN;

#define COPY4(dst,src) * (unsigned *)(dst) = * (const unsigned *)(src)

int lzo::lzo1x_decompress_safe ( const byte* in , byte* out, unsigned OutLen)
{
register byte* op;
register const byte* ip;
register size_t t;
register const byte* m_pos;

byte* const op_end = out + OutLen;

OutLen = 0;
op = out;
ip = in;

if (*ip > 17)
{
t = *ip++ - 17;
if (t < 4) goto match_next;
assert(t > 0);// return LZO_E_ERROR;
NEED_OP(t);
do *op++ = *ip++; while (--t > 0);
goto first_literal_run;
}

while (1 )
{
t = *ip++;
if (t >= 16) goto match;
if (t == 0)
{
while (*ip == 0)
{
t += 255;
ip++;
}
t += 15 + *ip++;
}
assert(t > 0); NEED_OP(t+3);

COPY4(op,ip);
op += 4; ip += 4;
if (--t > 0)
{
if (t >= 4)
{
do {
COPY4(op,ip);
op += 4; ip += 4; t -= 4;
} while (t >= 4);
if (t > 0) do *op++ = *ip++; while (--t > 0);
}
else
do *op++ = *ip++; while (--t > 0);
}

first_literal_run:

t = *ip++;
if (t >= 16) goto match;

m_pos = op - (1 + M2_MAX_OFFSET);
m_pos -= t >> 2;
m_pos -= *ip++ << 2;

TEST_LB();
NEED_OP(3);
*op++ = *m_pos++; *op++ = *m_pos++; *op++ = *m_pos;

goto match_done;

do {
match:
if (t >= 64)
{

m_pos = op - 1;
m_pos -= (t >> 2) & 7;
m_pos -= *ip++ << 3;
t = (t >> 5) - 1;
TEST_LB(); assert(t > 0); NEED_OP(t+3-1);
goto copy_match;
}
else if (t >= 32)
{
t &= 31;
if (t == 0)
{
while (*ip == 0)
{
t += 255;
ip++;
}
t += 31 + *ip++;
}

m_pos = op - 1;
m_pos -= (ip[0] >> 2) + (ip[1] << 6);

ip += 2;
}
else if (t >= 16)
{

m_pos = op;
m_pos -= (t & 8) << 11;

t &= 7;
if (t == 0)
{
while (*ip == 0)
{
t += 255;
ip++;
}
t += 7 + *ip++;
}

m_pos -= (ip[0] >> 2) + (ip[1] << 6);

ip += 2;
////// done
if (m_pos == op)
{
assert(t==1);
if (m_pos!=op_end)
return LZO_E_LOOKBEHIND_UNDERRUN;
return ip-in;
}
m_pos -= 0x4000;
}
else
{
m_pos = op - 1;
m_pos -= t >> 2;
m_pos -= *ip++ << 2;

TEST_LB();
NEED_OP(2);
*op++ = *m_pos++; *op++ = *m_pos;
goto match_done;
}

TEST_LB();
assert(t > 0);
NEED_OP(t+3-1);

if (t >= 2 * 4 - (3 - 1) && (op - m_pos) >= 4)
{
COPY4(op,m_pos);
op += 4; m_pos += 4; t -= 4 - (3 - 1);
do {
COPY4(op,m_pos);
op += 4; m_pos += 4; t -= 4;
} while (t >= 4);
if (t > 0) do *op++ = *m_pos++; while (--t > 0);
}
else
{
copy_match:
*op++ = *m_pos++; *op++ = *m_pos++;

do *op++ = *m_pos++; while (--t > 0);

}
match_done:

t = ip[-2] & 3;
if (t == 0) break;
match_next:
assert(t > 0); assert(t < 4); NEED_OP(t);
*op++ = *ip++;
if (t > 1) { *op++ = *ip++; if (t > 2) { *op++ = *ip++; } }

t = *ip++;
} while (1 );
}
// return LZO_E_EOF_NOT_FOUND;/never gets here

}

</nowiki></pre>

=Related Page(s)=

[[BIS_File_Formats#3D_Model_File_Formats|Model File Formats]]
[[Category:BIS_File_Formats]]
[[Category:ArmA: File Formats]]