Questions tagged [lossless-compression]
Lossless data compression is a class of data compression algorithms that allows the original data to be perfectly reconstructed from the compressed data.
lossless-compression
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Compress GIF image and append in formdata
In one of my .Net project, I want to compress image (jpg, jpeg, png, gif...) by javascript. Except GIF, compress is working fine. I tried different ways. But gif compress not working. Some process is ...
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can a random byte-array be decompressed? What algorithm would be used?
I can insert any byte-array into a compression-algorithm like Lempel-Ziv and i will get a lossless compressed byte-array back. I can decompress this again.
But is there an algorithm that can ...
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Compressing a list of low bit integers (2, 3, 4 bits)
I have a relatively long list of low bit integers by size 16*10^6.
The sparsity level of this list is about 40%, so applying any sparse matrix does not work.
The first step I tried Run-length encoding,...
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Save compressed DICOM image without having to temporally save uncompressed DICOM
I have a DicomInterface class that inherits from DcmDataset class. After setting the DICOM tags, I want to save the DICOM image with JPEG Process 14 transfer syntax. If I first save the DICOM file ...
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How does a decompressor know the huffman tree that was used by the compressor?
From what i understood Deflate is LZ77 and Huffman encoding but i have been looking at the structure of .zip file but i haven't seen where to extract information about Huffman tree that was used in ...
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What is the difference between 7-zip Deflate and zlib.compress()?
Helo everyone
I am trying to understand Deflate compression but from what i have seen i think i have misunderstood or done something wrong.
So i grabbed a source code for 7zip so i might understand ...
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Shifting a 1 bit into high and 0 bit into low in arithmetic compression
I'm trying to write my own arithmetic compressor. I'm cheating a little bit by referencing the implementation I found in https://marknelson.us/posts/2014/10/19/data-compression-with-arithmetic-coding....
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Questions about the frequency table in arithmetic encoding compression
I have a high level idea of how arithmetic coding works, but in the sources I've read (https://neptune.ai/blog/lossless-data-compression-using-arithmetic-encoding-in-python-and-its-applications-in-...
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How do I set up CloudLab for a Simple Experiment?
I am trying to test compression/decompression algorithms on GPU and CPU machines. I am very new to CloudLab and I have almost 0 idea of how to set it up and use it. I was hoping to get some help on ...
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Compression of Database using FP trees
I have a dataset of around 200 MB, containing only integers. My goal is to use FP-trees to compress this dataset and reduce the final output file size. This is for academic purposes so I can't use ...
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Is there any way to to compress large size pdf file using only python library no external .exe
I have 100mb pdf file of single page with color full text of different font multiple image. Is there a way to compress this pdf to minimum size and then decompress it back to original size with same ...
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Compute the compression ratio by using Huffman encoding
I am trying to compute the compression ratio in this way
1- compute the original size in byte:
int size= sizeof(inputarr)/sizeof(inputarr[0]);
originalsize = size *(sizeof(int))
2-Compute the ...
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Compute the compression ratio for Huffman algorithm
I used this code HuffmanCodeto compress this text
...
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combining two seperate numbers into a single byte and being able to uncombine them later
I'm not sure this is possible, but perhaps there's something I'm not thinking about. I have two numbers that I want to combine together into a single byte (8 bits). The first number can have 80 ...
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Compressing multi-spectral image
I need to compress multispectral images in a lossless way, all the classical compression algorithms (Zip,Rar,Gzip,Deflate etc...) don't give very good results, with compression rates of approximately ...
