Questions tagged [deflate]
deflate is a lossless data compression format, and also refers to implementations that compress to the deflate format. The deflate format was created by Phil Katz of PKWare for the PKZip (.zip) archive format. Public domain software provides deflate and inflate functionality in the gzip utility and the zlib library.
deflate
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How to decompress IDAT compressed data
i wrote some python code to extract each chunk of a PNG image , i've tried with 3 different images and it works perfectly , it also matches perfectly what's displayed in https://rameshvarun.github.io/...
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Compression Discrepancy in BMEcat XML Files Generated via Talend vs. eprocat
Hello Stack Overflow community,
I am currently working on a project where I generate a BMEcat XML catalog (version 1.2) using Talend Studio. I have encountered a peculiar issue related to file ...
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.net DeflateStream fails to decode a PDF stream object content
I created a PDF using the export function of Word 2019.
I'm parsing the PDF as a text and I capture the content of the stream object:
4 0 obj
<</Filter/FlateDecode/Length 344>>
stream
...
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Iterate through all possible code length distributions for canonical Huffman
Given the constraints imposed by Deflate (as used in zlib), I want to iterate through all possible code length distributions to find extreme cases which might break my assumptions.
Deflate assigns the ...
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(Deflate) Is using a code of 284 for a distance pair with a length of 258 allowed in a Huffman compressed Deflate block?
I've been working on a program which aims to optimise deflate compressed files through trying possibly more efficient ways of representing the compressed data, and I recently found a file which uses ...
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1
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Valid gzip file contains a large block of NULL bytes - why?
I have a tar.gz file which contains large blocks of NULL bytes (>1kb). The archive seems to be valid (checked via gzip -t <file-name>) and extraction works properly without issues.
The NULL ...
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zlib.js Error code: "Z_DATA_ERROR" errno: -3
When i try to extract one file using node.js with package node-stream-zip its getting error like
code: "Z_DATA_ERROR"
errno: -3
message: "too many length or distance symbols"
stack:...
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Heuristics to improve brute forcing the location of a DEFLATE block
I work in the data recovery industry. Sometimes a document (.docx) has the beginning overwritten but most of the file might still be intact. A 'docx' is really just a zip file, and the primary ...
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Compression Gzip/7Zip [closed]
When I calculate the entropy values of files compressed with Gzip, PKZIP, 7ZIP and Winrar, I find that the compression rate of Gzip is higher than the others. The entropy value is higher (indicating ...
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Maximum size of compressed data using Python's zlib
I'm writing a Python library that makes ZIP files in a streaming way. If the uncompressed or compressed data of a member of the zip is 4GiB or bigger, then it has to use a particular extension to the ...
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zlib difference in size for level=0 between Python 3.9 and 3.10
In this code that uses zlib to encode some data, but with level=0 so it's not actually compressed:
import zlib
print('zlib.ZLIB_VERSION', zlib.ZLIB_VERSION)
total = 0
print('Total 1', total)
...
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Test that a ZIP doesn't require zip64 support
I'm looking to test some Python code makes zip files that dynamically chooses zip32 or zip64, and I would like to assert that in certain cases it really does create valid zip32 files by opening it in ...
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How to properly decode a deflate compressed string in C#? [duplicate]
I want to decode a string that I have as
content-encoding: deflate
It is deflate only, it does not have any other compression algorithm.
x?uO?
?0►??§!g§?↨¶?ho??6]?@6←??P??,?¶??????♂?=?♦??►?h☼????,?R☻...
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After decrypting a TLS record, how do I know what decompression to apply, if any?
I successfully implemented TLS 1.3 decryption for specific records, but I am having a hard time figuring out how to go get readable plain text (assume it is compressed).
The TLS record does not ...
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Malformed PNG pixel data from deflate "unknown edge cases"
For the past 2 months, I've been implementing a png/deflate decoder, (for various reasons but mainly for learning purposes) but only returns the correct expected data in some cases.
Here in this table,...
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