Lossless compression algorithms

Lossless compression algorithms. Example: Text, medical imaging, satellite imaging, etc. Maintaining quality of data reconstructed at high compression rate is a very difficult part of the data compression technique. In computer science and information theory, a Huffman code is a particular type of optimal prefix code that is commonly used for lossless data compression. Find out which file types use lossless compression and how to apply it to your photos. [17] Mar 18, 2022 · For the 1 MB batch size, 315 compression and decompression operations are performed. Run-length encoded (RLE), low-ratio JPEG and the more recent JPEG lossless compression standard (JPEG-LS) algorithms are examples of lossless Mar 25, 2024 · Standard lossless compression algorithms include Huffman coding, arithmetic encoding, and run-length encoding. The opposite would be a lossy compression algorithm. org are unblocked. It is based on a variation of the low complexity lossless compression method (LOCO-I) , and Run-length encoding (RLE) is a form of lossless data compression in which runs of data (consecutive occurrences of the same data value) are stored as a single occurrence of that data value and a count of its consecutive occurrences, rather than as the original run. The encoder examines the input sequence through a sliding window as shown in Figure 9. In lossless compression algorithms, there is no loss of information, i. Images are now employed as data in a variety of applications, including medical imaging, remote sensing, pattern recognition, and video processing. Lossless compression is generally used to compress text. It means that lossless compression algorithms can accurately reconstruct the original data from the compressed data. 1) • B0–number of bits before compression • B1–number of bits after compression Li, Drew, Liu 3 0 1 B compressionratio B = Jan 15, 2022 · Lossless is the preferred compression algorithm for visual arts: photography, graphic design, digital art, and more. A lossless compression algorithm compresses data such that it can be decompressed to achieve exactly what was given before compression. The Alpha Jul 16, 2022 · Classical lossless compression algorithm highly relies on artificially designed encoding and quantification strategies for general purposes. BMP, . Karam, in Handbook of Image and Video Processing (Second Edition), 2005 1 Introduction. We propose an efficient deep lossless compression algorithm, which uses arithmetic coding Huffman coding is an entropy-based coding method and it provides lossless compression. Novel digital photo cameras are able to sample the light field. Feb 7, 2023 · The bitmap will likely gain the greatest compression ratio, the PNG a very small compression ratio (especially if it is a PNG of the bitmap), and the executable will most likely be "stored" rather than compressed at all. Our method encodes the mesh connectivity data based Feb 1, 2021 · A lossless compression algorithm for point and gridded wind plant data is developed and analyzed in (Louie and Miguel, 2012). LZSS (Lempel-Ziv-Storer-Szymanski) Algorithm. Why Should You Use Lossless Compression? As we mentioned earlier, lossless compression uses an algorithm to compress images and other file types. Although each algorithm is an independent in its In the world of dictionary coding and probability based encoding, the floating point weirdness that is arithmetic coding is a refreshing and surprisingly efficient lossless compression algorithm. Compression algorithms can be classified as two broad classes: lossless and lossy compressions. The various compression algorithms can be broadly classified into two categories –lossless compression algorithms and lossy compression algorithms. These techniques ensure that the original data can be perfectly reconstructed from the compressed data, making them particularly important for applications in signal and image processing, where maintaining quality and accuracy is crucial. org and *. The next several chapters deal with lossy compression algorithms as they are commonly used for image, video, and audio compression. The dictionary is a portion of the previously encoded sequence. Jul 22, 2024 · LZ4, a widely used cross-platform open-source compression algorithm known for its speed and efficiency, has just reached version 1. , worse) compression ratio than the similar LZO algorithm, which in turn is worse than algorithms like DEFLATE. What you need here is a lossless compression algorithm. Algorithm Example Shortcomings Variations: The Concept. the reconstructed data is exactly same as original data. , the original and decompressed are perfectly correlated). Huffman while he was a Sc. This makes it a great option for compressing sensitive data or important files. What would be the best algorithm to compress this? I tried the deflate algorithm but that gives me only 50% compression. [] proposed an algorithm for compressing data sequentially. LCA achieves a better compression ratio than that of existing DNA-oriented compression algorithms, when compared to GenCompress, DNACompress, and DNAPack. Multimed. The LOCO-I lossless image compression algorithm: Principles and standardization into JPEG-LS. When you expand it again, the file contains everything needed to restore the original data. The Huffman Coding algorithm [] uses the probability distribution of the alphabet to develop codes for symbols based on a binary tree. Thus, with looking at the importance of data compression, lossless compression methods are recommended for various DNA file formats such as FASTA and FASTQ file formats. In lossless data compression algorithms first the redundant information is removed from the data and then the data is compressed at the source end. The second step is to start with the smallest source and trace back to the original source. Unix’s ‘compress’ command, among other uses. LZAV is a fast general-purpose in-memory data compression algorithm based on now-classic LZ77 lossless data compression method. Lossless Coding. To overcome Nov 23, 2021 · Despite extensive progress on image generation, common deep generative model architectures are not easily applied to lossless compression. Most of these algorithms are using prediction-based compression algorithms, where each value is predicted and the residual between the prediction and true Explanation: In lossless compression the data upon decompression doesn’t lose its detail. Also if you can point me to the java implementation of such algorithm that would be great. Jun 26, 2024 · Diagrams: (a) is the LZ77 lossless compression algorithm, (b) is the PPMd lossless compression algorithm, (c) is the proposed BPPMd lossless compression algorithm, and (d) represents the byte encoding module. Jan 1, 2015 · A second class of compression algorithms is based on a predictive coding approach. Figure 3a: Compression throughputs for various batch sizes operating on a 314 MB file. Since its introduction in 1977, the LZ77 has been improved and many variants appeared, such as the LZSS (Lempel Ziv Storer Szymanski) and the LZMA (Lempel Ziv Markov chain algorithm). At a 400 MB batch size, a single compression and decompression operation is performed. BPPMd integrates the byte encoding module into the design space and implementation of the PPMd algorithm. Upon decoding audio compressed with a lossless codec such as FLAC or ALAC , the result is identical in every way to the original sound, down to the bit. Because codes take up less space, the overall size of the data is reduced. LOCO-I (LOw COmplexity LOssless COmpression for Images) is the algorithm at the core of the new ISO/ITU standard for lossless and near-lossless compression of continuous-tone images, JPEG-LS. Lempel–Ziv–Welch (LZW) is a lossless compression algorithm developed by Abraham Lempel, Jacob Ziv and Terry Welch in 1984. The file formats like RAW, BMP, GIF, and PNG can all benefit from lossless-image-compression algorithms. " 1 day ago · Based on the optimized algorithm, a high-throughput flexible lossless compression and decompression architecture (HFCD) is proposed, which achieves higher pixel per clock (PPC) with less hardware cost. In near-lossless compression, a certain measure of quality loss is accepted without losing remarkable information. For example, VAEs suffer from a compression cost overhead due to their latent variables. Nov 30, 2021 · [Dominic Szablewski] was tinkering around with compressing RGB images, when he stumbled upon idea of how to make a simple lossless compression algorithm, resulting in the Quite OK Image Format, whi… Feb 22, 2021 · arithmetic coding. [2] They are also known as LZ1 and LZ2 respectively. Existing 3D mesh methods usually require complex data structures and time-consuming processing. There are many good reasons to study compression algorithms. Lossy compression can remove data from a file. May 7, 2024 · 3. [1] By contrast, lossy compression permits reconstruction only of an approximation of The Lempel–Ziv–Markov chain algorithm (LZMA) is an algorithm used to perform lossless data compression. The algorithm takes the form of two stages, the first stage translates a string into a floating point range and the second stage translates this into Lecture 6: Lossless Compression Lecturer: Tsachy Weissman Scribe: Seungmin Lee, Brian Do, Cody Peterson 1 Variable Length Lossless Compression (Ch. Scientific computing produces, transfers, and stores massive amounts of single- and double-precision floating-point data, making this a domain that can greatly benefit from data compression. 1 Compression As you probably know at this point in your career, compression is a tool used to facilitate storing large data sets. Most lossless compression algorithms use some variation of finding patterns and expressing those in a compact form. PNG. ; Sapiro, G. To gain insight into what makes an effective lossless compression algorithm for such data, we generated over nine million algorithms and selected the one that yields the highest compression ratio on 26 Mar 14, 2024 · Dictionary compression. It also gives a score based on a weighted average of runtime and the compression ratio. However, with the development of network transmission speed, most of lossless compression algorithms cannot be applied due to their large algorithm code size and high resource overhead, especially in the embedded field. The goal of lossless image compression is to represent an image signal with the smallest possible number of bits without loss of any information, thereby speeding up transmission and minimizing storage requirements. The lossless compression technique is best for text-heavy images and pictures with a transparent background. It has been under development since either 1996 or 1998 by Igor Pavlov [1] and was first used in the 7z format of the 7-Zip archiver. Apr 5, 2024 · This article proposes two novel lossless and near-lossless compression methods, employing our recent seed generation and quadrature-based square rooting algorithms, respectively. Streaming giants Spotify, Apple Music, and TIDAL use this method to speed up content loading without reducing music quality. In order to develop applications for efficiently storing and transmitting such information, it is important to study image coding architectures providing high compression ratios. Lossy compression algorithms involve the reduction of a file’s size usually by removing small details that require a large amount of data to store at full fidelity. We have compared our algorithm with other state of the art big data compression algorithms namely gzip, bzip2, fastqz (Bonfield and Mahoney, 2013), fqzcomp (Bonfield and Mahoney, 2013), Quip (Jones et al. If you're seeing this message, it means we're having trouble loading external resources on our website. However, there is something to note about how well lossless compression serves specific niches: The range of Pages in category "Lossless compression algorithms" The following 78 pages are in this category, out of 78 total. It is lossless, meaning no data is lost when compressing. 5) Last lecture, we talked about how using the AEP, entropy emerges when you want to describe source sym-bols in xed length at nearly lossless compression. Aug 27, 2024 · Video compression can achieve compression ratios approaching 20-to-1 with minimal distortion. Recent advances in deep learning allow us to optimize probabilistic models of complex high-dimensional data efficiently. , financial data) could pose a problem. The increase in compute power and development of sophisticated simulation models with higher resolution output triggers a need for compression algorithms for scientific data. As an imaginary example of the concept, when encoding an image built up from Dec 1, 2023 · In particular, the latter is generally allowed by the implementation of the lossless compression algorithms using suitable parameters addressed as compression level. Sep 19, 2023 · Lempel-Ziv Algorithm. Algorithms used in Lossless compression are: Run Length Encoding, Lempel-Ziv-Welch, Huffman Coding, Arithmetic encoding etc. org In this paper, we discuss algorithms of widely used traditional and modern compression techniques. The types of format that can benefit from lossless image compression are . In an effort to find the optimum compression algorithm, we compare commonly used modern compression algorithms: Deflate, Bzip2, LZMA, PPMd and PPMonstr by analyzing their performance on Silesia corpus. Explore Huffman, Shannon-Fano, LZ77, and LZ78 algorithms with examples and diagrams. For the lossy compression, the information can be thrown away and still be acceptable. CALIC is a very efficient lossless compression algorithm with a high compression ratio [33, 38]. Combining a lossless algorithm with the proper depth and resolution can achieve almost a “one-to-one” copy. kasandbox. This algorithm is useful for data involved in wind plant monitoring and operation. Lossless data compression algorithms are Run Length Encoding, Huffman encoding, Shannon fano encoding, Arithmetic encoding, Lempel Ziv Welch encoding, etc. Ravin Kumar on 19 September, 2016. • If the compression and decompression processes induce no information loss, then the compression scheme is lossless; otherwise, it is lossy. We Mar 18, 2024 · It’s a powerful data transformation method that is used in a lossless data compression algorithm. LZ77 and LZ78 are the two lossless data compression algorithms published in papers by Abraham Lempel and Jacob Ziv in 1977 [1] and 1978. If you're behind a web filter, please make sure that the domains *. In lossy compression, it is impossible to restore the original file due to the removal of essential data. As loss of information is Feb 18, 2022 · In this paper, we propose an efficient compression algorithm specifically for grayscale images. wikipedia. Several compression algorithms are currently under development. Algorithms used in Lossy compression are: Transform coding, Discrete Cosine Transform, Discrete Wavelet Transform, fractal compression etc. Lossless Compression Algorithms. student at MIT, and published in the 1952 paper "A Method for the Construction of Minimum-Redundancy Codes". In information technology, lossy compression or irreversible compression is the class of data compression methods that uses inexact approximations and partial data discarding to represent the content. kastatic. Sep 3, 2021 · Lossless Compression Algorithms# As the name implies the lossless compression algorithms belong to a category of data compression algorithms that compress the files without losing any of their content. JPEG-LS is the ISO/ITU standard for lossless and near-lossless compression of continuous-tone images. Lossless compression methods are reversible. Consequently, there is a continued need for more adaptable compression algorithms to effectively handle various data patterns in time series data. Feb 22, 2017 · In an effort to find the optimum compression algorithm, we compare commonly used modern compression algorithms: Deflate, Bzip2, LZMA, PPMd and PPMonstr by analyzing their performance on Silesia May 21, 2024 · What is Lempel–Ziv–Welch (LZW) Algorithm ? The LZW algorithm is a very common compression technique. All numbers are unique and progressively increasing. The algorithm uses wind speed-to-wind power relationship, temporal and spatial correlations in the data. Jul 16, 2024 · But Lossless Compression does not reduce the size of data. Learn about lossless compression techniques for discrete data, such as text, images, and video. J. The obtained Mar 24, 2020 · Many researchers believe that lossless compression schemes are particularly needed for biological and medical data, which cannot afford to lose any part of their data . 2015, 74, 10605–10619. This list may not reflect recent changes. However, when attempting to implement a compressor on hardware, the problems discussed in this chapter inevitably arise. Reversible Compression (Lossless) Upon decompression, the image is perfectly reconstructed and numerically identical to the original (i. This algorithm is typically used in GIF and optionally in PDF and TIFF. Given a mesh represented by its vertices and triangular faces, we present a novel, fast, and straightforward encoding algorithm. With the rapid development of deep learning, data-driven methods based on the neural network can learn features and show better performance on specific data domains. A lossless algorithm widely used for GIF and TIFF formats, this creates a codebook for encountered sequences. These techniques are used to reduce data size for storing, handling, and transmitting content. Firstly, we design a new 2-Dimensional Logistic-Like Hyperchaotic Map (2DLLHM), which has more complex dynamics than some existing known chaotic systems, and can be used to build a Oct 11, 2019 · An improved lossless image compression based arithmetic coding using mixture of non-parametric distributions. There are two different sorts of goals one might hope to achieve with compression: • Maximize ease of access, manipulation and processing If you're seeing this message, it means we're having trouble loading external resources on our website. LZAV holds a good position on the Pareto landscape of factors, among many similar in-memory (non-streaming) compression algorithms. GZIP is a popular, patent-free compression Oct 10, 2015 · Results: We introduce a new lossless non-reference based FASTQ compression algorithm named Lossless FASTQ Compressor. Aug 1, 2024 · Lossless compression algorithms reduce the size of the audio without compromising the quality or fidelity of the sound. One of the earliest lossless compression algorithms, Dictionary compression (in particular, LZ-based compression) is the ancestor of many compression schemes used today, including LZW (used in GIF) and DEFLATE (used in PNG, gzip). e. Data compression is more significant thing in recent world. Oct 28, 2021 · In addition to this, it also provides a review of important pieces of the literature relating to advancements in the fundamental lossy and lossless compression algorithms. ZIP is an archive file format that supports lossless data compression. This overhead can only be partially eliminated with elaborate schemes such as bits-back coding, often resulting in poor single-sample compression rates. Lossless compression is possible because most real-world data exhibits statistical redundancy. To overcome Ravdec is a module written in python, which is based on a Lossless Data Compression Algorithm designed by Mr. Lossless compression is a class of data compression that allows the original data to be perfectly reconstructed from the compressed data with no loss of information. Lina J. Authors’ abstract We describe a block-sorting, lossless data compression algorithm, and our implementation of that algorithm. Several lossless data compression algorithms are available, Lempel Ziv Marcov Chain Algorithm (LZMA) proves to be efficient in unknown byte stream compression for reliable Lossless Data Compression which gives better compression ratio and can be hardware implementable. Transparency: 8-bit alpha channel is useful for graphical images. VP8 is a video compression format created by On2 Technologies as a successor to the VP6 and VP7 formats. Jan 16, 2024 · Step 3: Lossless compression can restore the original data from the compressed files. Batching the data in this way doesn’t affect the low-level batch API. Genetics compression algorithms are the latest generation of lossless algorithms that compress data (typically sequences of nucleotides) using both conventional compression algorithms and genetic algorithms adapted to the specific datatype. This paper aims at exploring the performance of state-of-the-art lossless image compression algorithms applied to raw light field images. Lossless data compression algorithms are widely used by data communication systems and data storage systems to reduce the amount of data transferred and stored. GIF, and . It’s possible because of the reversible file making process. Examples of lossless compression include gzip, brotli, Zstandard, WebP, and PNG. LZ4 is lossless compression algorithm, providing compression speed > 500 MB/s per core, scalable with multi-cores CPU. to systematically compare lossless compression algorithms is the Archive Comparison Test (ACT) by Jeff Gilchrist. The paper counted more than 40 compression algorithms. Apr 15, 2024 · Lossy compression: The lossy compression is based on VP8 key frame encoding. Feb 26, 2019 · The necessity of data transfer at a high speed, in fast-growing information technology, depends on compression algorithms. Nov 23, 2021 · Despite extensive progress on image generation, common deep generative model architectures are not easily applied to lossless compression. Whereas on the other hand the lossy algorithms tend to miss out the minor details of the data involved. In 2012, a team of scientists from Johns Hopkins University published a genetic compression algorithm Jul 8, 2024 · Lossless compression is a class of data compression algorithms that allows the original data to be perfectly reconstructed from the compressed data. Here, we concentrate on lossless compression. Jun 8, 2021 · CALIC is a very efficient lossless compression algorithm with a high compression ratio [33, 38]. e Mar 20, 2023 · Furthermore, lossless compression is increasingly used for audio files. That in turn means that if our encryption algorithm manages to compress an input, then that fact reveals information on the input. There is a trade-off between the time and memory that compression algorithms require and the compression that they achieve. The ideal photographs for the lossless compression approach are those with a transparent background and a lot of text. Applications of lossless and lossy compression. It reports times and compression ratios for 100s of compression algorithms over many databases. It uses a “sliding window” method. Lossy data compression algorithms are: Transform coding, Discrete Cosine Transform, Discrete Wavelet Transform, fractal compression, etc. 1 Dynamic Huffman coding. JPEG-LS was developed with the aim of providing a low-complexity lossless and near-lossless image compression standard that could offer better compression efficiency than lossless JPEG. [16] DEFLATE, a lossless compression algorithm developed by Phil Katz and specified in 1996, is used in the Portable Network Graphics (PNG) format. It features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed limits on multi-core systems. The performance of lossless compression algorithms have limits. [ 3 ] These two algorithms form the basis for many variations including LZW , LZSS , LZMA and others. Huffman coding allows the creation of an optimized binary tree, significantly reducing the number of bits used per pixel, and improving the compression ratio. Apr 29, 2024 · Three-dimensional mesh compression is vital to support advances in many scenarios, such as 3D web-based applications. May 28, 2020 · LZ77, released in 1977, is the base of many other lossless compression algorithms. The process of finding or using such a code is Huffman coding, an algorithm developed by David A. Lempel-Ziv 77 (LZ77) algorithm is the first Lempel-Ziv compression algorithm for sequential data compression. In the field of compression algorithms, lossless compression is used in various fields of data storage and transmission because it can restore data without distortion. , it is possible to exactly recover the original data from compressed data [1,2]. pression and decompression processes induce no information loss, the compression scheme is lossless; otherwise, it is lossy. 1429 in all possible cases, It accepts data of following format: alphabets,numbers, and symbols. It is used in situations where the loss of information is unacceptable. Data compression is the science and skill of representing It is a simple and efficient baseline algorithm which consists of two independent and distinct stages called modeling and encoding. The Apr 5, 2012 · The reason is that we know there is no way to compress every input (information theoretically this is impossible). By combining simplicity with the compression potential of Mar 19, 2018 · This paper presents the pillars of lossless compression algorithms, methods and techniques. One of the key features of BWT is its ability to group together similar characters in a string, which is a key factor in achieving efficient compression. Feb 17, 2021 · If the compression and decompression processes induce no information loss, the compression scheme is lossless; otherwise, it is lossy. Lossless compression: The lossless compression format is developed by the WebP team. It is based on a variation of the low complexity lossless compression method (LOCO-I) [ 29], and use context models in The current work proposes a Lossless Compression Algorithm (LCA), providing a new encoding method. English text can generally be compressed to one-half or one-third of its original size. Basically, this class of algorithms is based on the fact that in most cases it is sufficient to encode only those residues, resulting from the difference between the predicted value and the actual value, which fall inside a relatively small range [− R, R] and to transmit the values outside this range (i. There are a ton of compression algorithms out there. Nov 12, 2008 · All integers are positive. Compression quality can be measured in various ways. In this method, LZ77 manages a dictionary that uses triples to represent: Jan 1, 2014 · If the compression and decompression processes induce no information loss, the compression scheme is lossless; otherwise, it is lossy. It is conceived as a "low complexity projection" of the universal context modeling paradigm, matching its modeling unit to a simple coding unit. The algorithm first arranges the order of probabilities of symbols and forms a symbol tree by combining the lowest probability symbols into a single symbol. The ZIP file format permits a number of compression algorithms, though DEFLATE is the most common. These developments have opened up many opportunities regarding lossless compression. Lossless compression is mainly used to compress: images; sound; text; It is generally the technique of choice for detailed product images, photography showcases, text files and spreadsheet files, where the loss of picture quality, words or data (e. Note that the algorithm cannot be lossy. 3 19. To associate your repository with the lossless-compression-algorithm topic, visit your repo's landing page and select "manage topics. Tools Appl. Sep 19, 2019 · The compression ratio of the resulting compression scheme heavily relies on the first problem: the model capacity. There are a few compression algorithms that can achieve lossless The LZ4 algorithm aims to provide a good trade-off between speed and compression ratio. ; Seroussi, G. Our approaches are mainly algorithmic. Typically, it has a smaller (i. In this paper, a new lossless image compression algorithm is proposed, which uses both wavelet and fractional transforms for image compression name implies, lossless compression refers that no loss of information i. RAW, . Learn what lossless compression is, how it works, and what are its advantages and disadvantages. Definition. This lossless algorithm uses a textual substitution principle based on the dictionary coding . Lossless compression techniques are methods used to reduce the size of data files without losing any information. There are two major categories of compression algorithms: lossy and lossless. That means that a lossless compression algorithm can really only compress certain input strings. , 2012), DSRC2 (Roguski Thus, lossless data compression algorithms help in retrieving the original data and also make the transfer fast by minimizing the size of the information. Jun 15, 2023 · In this paper, a lossless image compression and encryption algorithm combining JPEG-LS, neural networks and hyperchaotic mapping is proposed to protect the privacy of digital images and reduce data storage space. J. A block-sorting, lossless data compression algorithm, and the implementation of that algorithm, that achieves speed comparable to algorithms based on the techniques of Lempel and Ziv, but obtains compression close to the best statistical modelling techniques. D. There have been various research works in the field of compression in the past that present the background of our work. Apr 22, 2007 · The goal is to build a fully-functional, hardware design for a GZIP encoder that could be used in data communication systems and data storage systems to boost overall system performance. [Google Scholar] Weinberger, M. Jan 1, 2024 · State-of-the-art floating-point lossless compression algorithms, such as Gorilla [10], TSXor [24] and Chimp [25], also experience inconsistent performance when compressing data with differing patterns. Ziv et al. . This compression algorithm have a fixed compression ratio of 1. It is used in the GIF format, introduced in 1987. g. However, LZ4 compression speed is similar to LZO and several times faster than DEFLATE, while decompression speed Compression and Huffman Coding Supplemental reading in CLRS: Section 16. The complete pixel information is recovered at Oct 20, 2021 · The most important lossless-compression algorithm is LZW, which is simple and effective and can be found in lossless-compression software such as gz, bzip2, rar, and lzh. Jan 25, 2024 · Run-length encoding, arithmetic encoding, and Huffman coding are examples of common lossless compression algorithms. The main advantage of the former method lies in its acceptable complexity utilizing simple arithmetic operations, making it suitable for real-time onboard compression. See full list on en. 10. This latest update introduces significant enhancements, particularly multithreading support, which leverages modern multi-core processors to accelerate compression and decompression tasks in high-throughput environments. The prediction based technique is a lossless compression algorithm, where the difference of an original and predicted pixel is encoded using Golumb Rice (GR) code and transmitted [42]. • Compression ratio: •(7. A ZIP file may contain one or more files or directories that may have been compressed. uryyw gyctv josfy uqlj niuwm rspjz mosb crg qzvvamm hbikx