image compression algorithms
ZXNet echo conference «code.zx»
Hello, All
Are there any available form (source/pseudocode) of the Spectrum algorithms?
programs for packing/unpacking pictures?
Hello,Hrumer
Hru> Bystrov described the format of the packed data in Infernoguide
Hru> different packers, you can look there...
just in case, unpacking lc 4.0 and lc 5.2 in c/c++
File: lc4-5.zip http://zx.pk.ru/attachment.php?attachmentid=1833
Hello, BlastOff
Bystrov once described in Infernoguide the format of packed data of different
packers, you can look there...
Hello, psb
psb> hmm.. are there any console hrusts for PC?
Well, why not... I don’t remember where I found it, it’s possible that somewhere here, on
forum
File: wloadsp.rar http://zx.pk.ru/attachment.php?attachmentid=1835
Hello elf/2
hmm.. are there any console hrusts for PC?
Hello elf/2
wow :))) thank you very much! :)))
Hello, psb
Are there any hrum/hrust console unpackers (with sorts)?
Hello, BlastOff
There are both packers and unpackers. You need to contact elf/2.
there is also my version in C++ (in fact, classes are used only for the sake of
namespaces). IMHO my version will be more readable.
If necessary, I’ll drop it off when I get home.
Hello Sinus
Yes, you should, throw it in! :)
Hello, BlastOff
In short, who needs crunching and de-crunching in classes, catch it.
For good measure, of course, I should have made the methods static, but I was screwed.
File: hrust-src.zip http://zx.pk.ru/attachment.php?attachmentid=1995
Hello Sinus
Sin> what is megalz?
Packer written by fyrex from mayhem.
Hello Sinus
Sin> in short, who needs crunching and de-crunching in classes, catch it.
Sin> for good measure, of course, it was necessary to make the methods static, but I
Sin> broken.
I wonder how optimally (within the packed data format) it packs
this "crunch in the classrooms"? What is "spd 0-3"? On 1 file it bypassed a little, on
friend lost a little to megalz. And since megalz's depacker is only 112 bytes,
then in this case there is a crunch in flight =)
Hello,Hrumer
Hru> lvd, I wonder if megalz uses any special ones
Hru> algorithms for improving compression quality (i.e. more optimal
Hru> selection of coded pairs) or is everything encoded “head-on”?
I don’t know, I didn’t write or break the packer. Depacker can be seen in later (than
later, the more likely it is that the latest depacker) mayhem releases. By
If you have any questions, please contact fyrex, he wrote it.
By the way, is there a depacker source for this packer, preferably moveable (LDIR)
and non-stacked? =)
Hello, lvd
"crunch in classes" - 1:1 port from Spekov's crunch. on this for all questions
regarding optimal/non-optimal packaging is not for me ^_~
what is megaz?
Hello, lvd
lvd, I wonder if megalz uses any special algorithms for
improving compression quality (i.e. more optimal selection of encoded pairs) or
Is everything encoded head-on?
Hello Sinus
Hello!
Has anyone tried to screw up the OLZH algorithm?
Hello, lvd
where can I get it?
Hello fyrex
well, don't worry about it ;)
let me test it
Hello, lvd
where can I get it?
Hello, lvd
I would like to see this packer. for if it packs better crunch with
depacker of 112 bytes, then this is at least interesting.
Hello Sinus
Sin> where can I get it?
I think I said where the depacker is, but the packer is only for internal use. By
If you have any questions, please contact fyrex, it is in the users here, if necessary, I’ll tell you in
PM.
Hello Sinus
What is better is of course unlikely...
but the fact that the unpacker is faster and smaller on a comparable
compression quality - yes.
2hrumer - unfortunately doesn’t use it, I wanted to work with it at one time
this approach to compression, but there was never much need - the limit
some can already be said to have been achieved (in this class of crunchers)
Hello,Hrumer
fyrex: oppa. I haven't seen a depacker from megalz. What I thought was called
bitbuster and RNC_ProPack... If it's not too much trouble, give me the text of the unpacker.
Hello jtn
jtn> yes, please post these 112 bytes as text directly to the forum
I'll drop it off from home. There's no here. By the way, fureh allowed to give the packer to individuals
- I’ll send it out too =)).
Hello,Hrumer
yes, please post these 112 bytes as text directly to the forum
Hello Sinus
fyrex: No way. I estimate the gain in terms of volume to be somewhere around 1..15%. Or maybe higher.
If Pavlov in his 7zip for the zip format indicates a gain of up to 8..10%, then with
Using "static codes" the gain will be much greater.
Hello axor
axo> Why only individual ones? What is the secret? It's better to post it here.
axo> Spectrumists will be grateful. What if they support him in some
axo> new commander (for example, QC).
The question is not for me - for fureh.
Hello, lvd
Депакер megalz v4
┌─- code ───
DEC40
;HL - from
;DE - to
LD A,#80
EX AF,AF'
MS LDI
M0 LD BC,#2FF
M1 EX AF,AF'
M1X ADD A,A
JR NZ,M2
LD A,(HL)
INC HL
RLA
M2 RL C
JR NC,M1X
EX AF,AF'
DJNZ X2
LD A,2
SRA C
JR C,N1
INC A
INC C
JR Z,N2
LD BC,#33F
JR M1
X2 DJNZ X3
SRL C
JR C,MS
INC B
JR M1
X6
ADD A,C
N2
LD BC,#4FF
JR M1
N1
INC C
JR NZ,M4
EX AF,AF'
INC B
N5 RR C
RET C
RL B
ADD A,A
JR NZ,N6
LD A,(HL)
INC HL
RLA
N6 JR NC,N5
EX AF,AF'
ADD A,B
LD B,6
JR M1
X3
DJNZ X4
LD A,1
JR M3
X4 DJNZ X5
INC C
JR NZ,M4
LD BC,#51F
JR M1
X5
DJNZ X6
LD B,C
M4 LD C,(HL)
INC HL
M3 DEC B
PUSH HL
LD L,C
LD H,B
ADD HL,DE
LD C,A LD B,0
LDIR
POP HL
JR M0
└── code ───
Hello, lvd
lvd> By the way, fureh allowed to give the packer to individuals - I will also send it out
lvd> =)).
Why only separate ones? What is the secret? It's better to post it here.
Spectrumists will be grateful. What if they support him in some new
commander (eg QC).
Hello fyrex
fyr> 2hrumer - Yes, it was 7z that opened my eyes to optimal compression
fyr> when the usual zip method achieves significantly greater compression...
fyr> But you have to take into account that the files on the spec are usually small, so
fyr> percentage gain is a few bytes! And suffer with the packer
fyr> will have to
fyr> long =)
I'll repeat the question. Is it possible to throw a packer here?
Hello,Hrumer
2hrumer - Yes, it was 7z that opened my eyes to optimal compression when
The usual zip method achieves significantly greater compression...
But you have to take into account that the files on the spec are usually small, so
winning in percentage is a few bytes! And you will have to suffer with the packer
long =)