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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Deflate - Inflate errors. Causing "incorrect header check" errors
I am working on implementing a SAMLSLO through HTTP-REDIRECT binding mechanism. Using deflate-inflate tools gives me a DataFormatException with incorrect header check.
I tried this as a stand-alone. ...
CommunityBot
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how to correctly decode data when bits are read from right to left?
I have had my fair share of understanding compression so with major discoveries that i will later post on github but i am still unable to manually decode few byte sequence accordingly.
here is the ...
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How to DEFLATE with a command line tool to extract a git object?
I'm looking for a command line wrapper for the DEFLATE algorithm.
I have a file (git blob) that is compressed using DEFLATE, and I want to uncompress it. The gzip command does not seem to have an ...
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Storing NTFS File Attributes in a Zip Archive
I have recently written a DEFLATE compressor and decompressor. As far as I understand the fstream Windows gives you does not include NTFS attributes as these are found in the $MFT. I need to go over ...
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how to decompress the DEFLATE compressed data
I wanted to create the internet trend BadApple in c++ console. By extracting every frame from the BadApple video using ffmpeg in .png format and reading RGB pixel data from it. I already have a boiler ...
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zlib inflate failing with errors like invalid distance too far back/ invalid block type/ invalid stored block lengths
Background: I am trying to deflate an in-memory buffer into a file and inflate it later for debugging.
In this case when the logs are flowing at a faster rate (about every millisecond) I see failures ...
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Time complexity of optimal DEFLATE compression
The DEFLATE algorithm is specified in RFC 1951. However, the encoder can choose freely whether to insert a literal byte, or a sub-match from output buffer for each input byte. Assuming that everything ...
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C++ zlib deflate/inflate and z_stream parameters
After I understood (with some help...) how work the compress and uncompress functions of the zlib library, I'm now trying to understand how deflate and inflate work. As far as I understand, compress ...
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Deflated file is larger than original and still valid
Inside a zip, I found this deflated file. It's around 1MB, but when inflated (pako.inflateRaw), the original is just 50kb. How is this possible? What happens to the rest of the data when inflated? I'...
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okhttp 3: how to decompress gzip/deflate response manually using Java/Android
I know that okhttp3 library by default it adds the header Accept-Encoding: gzip and decodes the response automatically for us.
The problem I'm dealing with a host that only accepts a header like: ...
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Why do i get more 256 false positive in PKZIP Decryption key verification?
I have been trying to brute force Key2 of ZipCrypto with first byte of CRC and last byte of encryption header to see how long would it take but i got more than 2000 valid keys.
From the APPNOTE, Key2 ...
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How to decompress the contents of a var to another var?
I'm trying to uncompress what's inside of a var into the same var or onto another.
I created a .gz file using gzip -k filename. It generated a filename.gz while keeping the original. I uploaded this ...
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What is the actual structure of a dynamic huffman block?
According to RFC1951:
3.2.7. Compression with dynamic Huffman codes (BTYPE=10)
The Huffman codes for the two alphabets appear in the block
immediately after the header bits and before the ...
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Is the DEFLATE compression algorithm in ZIP and GZip formats based on LZ77 or LZSS?
Wikipedia states that the DEFLATE algorithm (used among others by the ZIP and the GZip compression formats, but also by the PNG image format) is based on the LZ77 algorithm :
Deflate is a lossless ...
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How does one make a Zip bomb?
This question about zip bombs naturally led me to the Wikipedia page on the topic. The article mentions an example of a 45.1 kb zip file that decompresses to 1.3 exabytes.
What are the principles/...
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