Making a compressed digital archive might produce what type of file format?

I played with openssl to make a pub/prv key and create a signature of a file and validated it. I toyed with Cryptophane (windows gnupg frontend) and heard about keyservers+played with signing text. I however not ever signed a file archive. If i want to publish an archive (7z, rar or zip, it doesnt matter) and i'd like my users or software to be able to check if THAT archive has been signed how would i do that? The public key obviously would need to be available publically. But adding the signature to the archive is what bothers me. Does any software+archive allow me to sign and verify a compressed archive file? Why do you want to sign it? You could just create a SHA1 hash and make the hash available for your clients/users to check. This is sufficient to confirm that the file has not been tampered with. Although your users do need to have the ability to verify the hash but no harder than verifying a signature. @grawity - Not sure I follow - what's the point of tampering with the hash? I send you a file and the hash - you recreate the hash from the file and confirm it matches - this confirms the file has not been changed. In most circumstances this is all most people want - confirmation the file got from A to B unchanged. Certainly sounds like this is what the OP is after. A common method is to create a detached signature in a .sig file (usually a PGP signature by using gpg-b– X.509 is very uncommon), and provide both files in the same location. For example: ftp://ftp.gnupg....

extension mediatype definition files.xml all the manifest that records all of the files available for this book; also gives 2 checksums and a format definition for each file; provides the only mechanism for validating that the component data has been downloaded successfully .sfv all Simple file verification (SFV) is a file format for storing CRC32 checksums of files to verify the integrity of files. SFV is used to verify that a file has not been corrupted, but it does not otherwise verify the file’s authenticity. https://en.wikipedia.org/wiki/Simple_file_verification meta.xml all Internet Archive’s internal “management” metadata; a proprietary XML format, this file includes information about the scan event (date, # of pages, operator, station, etc.), the contributor, basic bib data (title, author, subject, language), and a set of identifiers .wma audio Windows Media Audio (WMA) is a series of audio codecs and their corresponding audio coding formats developed by Microsoft. https://en.wikipedia.org/wiki/Windows_Media_Audio .wav audio Waveform Audio File Format (WAV) is an audio file format standard for storing an audio bitstream. https://en.wikipedia.org/wiki/WAV .ogg audio Vorbis is a free and open-source software project. The project produces an audio coding format and software reference encoder/decoder (codec) for lossy audio compression. Vorbis is most commonly used in conjunction with the Ogg container format and it is therefore often referred to as Ogg Vorbis. https:/...

What is a ZIP file? File compression is an important part of the digital workspace. ZIP files use compression to send more data at faster speeds than has ever been possible. This is why ZIP files are such a popular tool for businesses all across the world. But what exactly is a ZIP file? ZIP is a common file format that’s used to compress one or more files together into a single location. This reduces file size and makes it easier to transport or store. A recipient can unzip (or extract) a ZIP file after transport and use the file in the original format. ZIP files work in much the same way as a standard folder on your computer. They contain data and files together in one place. But with zipped files, the contents are compressed, which reduces the amount of data used by your computer. Another way to describe ZIP files is as an archive. The archive contains all the compressed files in one location. So, the ZIP file format is one option to use if you need to make a single file or group of files smaller. So, how can you identify a ZIP archive file? Simple. Whenever you see the extensions .ZIP or .zip at the end of a file name, you’re looking at a ZIP file. The icon that represents the file would also change. Say you have a photo named vacation.jpg. After you zip this photo it now read vacation.zip and have a new icon. Is ZIP different from 7-ZIP or RAR? When you’re researching ZIP files, you may come across the term “7z file” or “7-ZIP.” This is an archiving format that uses a...

The image file formats that are most commonly used on the web are listed below. Abbreviation File format MIME type File extension(s) Summary Animated Portable Network Graphics image/apng .apng Good choice for lossless animation sequences (GIF is less performant). AVIF and WebP have better performance but less broad browser support. Supported: Chrome, Edge, Firefox, Opera, Safari. AV1 Image File Format image/avif .avif Good choice for both images and animated images due to high performance and royalty free image format. It offers much better compression than PNG or JPEG with support for higher color depths, animated frames, transparency, etc. Note that when using AVIF, you should include fallbacks to formats with better browser support (i.e. using the Supported: Chrome, Firefox (still images only: animated images not implemented), Opera, Safari. Graphics Interchange Format image/gif .gif Good choice for simple images and animations. Prefer PNG for lossless and indexed still images, and consider WebP, AVIF or APNG for animation sequences. Supported: Chrome, Edge, Firefox, IE, Opera, Safari. Joint Photographic Expert Group image image/jpeg .jpg, .jpeg, .jfif, .pjpeg, .pjp Good choice for lossy compression of still images (currently the most popular). Prefer PNG when more precise reproduction of the image is required, or WebP/AVIF if both better reproduction and higher compression are required. Support: Chrome, Edge, Firefox, IE, Opera, Safari. Portable Network Graphics image/...

xz compression has been rising in popularity because it offers smaller file sizes than gzip and bzip2. You’re still likely to see all three on a In this guide, we’re going to introduce you to xz compression, starting from basic examples to more specific and advanced usage. If you’ve worked with compressed gzip compression (files with the .tar.gz extension, for example) in the past, you’ll find that xz feels very familiar. In this tutorial you will learn: • How to create xz compressed archives from command line or GUI • How to decompress xz archives from command line or GUI Beginners guide to xz compression on Linux Software Requirements and Linux Command Line Conventions Category Requirements, Conventions or Software Version Used System Any Software xz Other Privileged access to your Linux system as root or via the sudo command. Conventions #– requires given sudo command $– requires given Compressing and decompressing xz archives on command line The simplest way to create an xz archive is by invoking the xz $ xz file1.txt The xz command in its simplest form, used to compress a single file with default options As you can see, file1.txt has now become file1.txt.xz. This is the same as using the -z (compress) option. To decompress the file, there are a few different options we can use, but these are the simplest. $ xz -d file1.txt.xz OR $ xz --decompress file1.txt.xz OR $ unxz file1.txt.xz Personally, I like using unxz because it’s easy to remember. But choose whichever you w...

When you go through camera menu options, you might come across a number of different options that are related to the way your RAW images are saved. One of those options is typically the type of compression that is applied to RAW files. There are several reasons why camera manufacturers provide RAW file compression options, but the most basic one is to save space. Let’s take a look at file compression options and explore differences between compressed, uncompressed and lossless compressed RAW files in more detail. Why Compress RAW Files? So why is there a need for RAW file compression? Isn’t compression for JPEG files only? Well, any file has a chance of having duplicates of information, and it does not matter if it is a JPEG or a RAW file in terms of compression potential. That’s why it is beneficial to have the option to compress RAW images in every camera, as there is direct potential in reduction of file sizes. And depending on whether you want to preserve all data (lossless), or parts of it (lossy), those space savings could be very significant. Below are the main reasons why manufacturers provide options for RAW compression: • To Save Space– this is the main reason, as the primary benefit of any type of compression is, first and foremost, space savings. Since compression allows RAW images to be smaller in size, more images can fit into the same memory card. Keep in mind that reduction in space affects the whole • To Write and Transfer Files Faster– when RAW images are...

Whether you’re dealing with images, music, or video files, it’s important to understand the difference between different types of formats and when to use them. Using the wrong format could ruin a file’s quality or make its file size unnecessarily large. Some types of media file formats are “lossy” and some types are “ Compression Explained We use compression to make files smaller, allowing them to download faster and take up less storage space. For example, when you take a photo, your camera captures all the light it can get and puts together an image. If you save the image in If we’re just uploading these files to a social network or placing them on a website, we don’t want these image files to take up so much space. A photo gallery with RAW images could take up hundreds of megabytes of space. RAW formats may be used by professional photographers to keep image quality high during the editing process, but they’re not intended for the average person. Instead, our camera or smartphone converts the image to a JPEG file. JPEG files are much, much smaller than RAW images. When you convert RAW to JPEG, some of the image data is “thrown out”, producing a much smaller file. The conversion process uses a compression algorithm that works well for photos, allowing them to look fairly good in spite of the compression. You may still see compression artifacts, depending on the quality setting. Note that lossy formats generally have a setting that controls how lossy they are. For exampl...

Contents • 1 Archiving only • 2 Compression + archiving • 3 Diff files • 4 Encrypted or cryptographically signed archives • 5 File splitting • 6 Filesystem backup and restoration • 7 Institutional archiving • 8 Metadata formats • 9 Program/App/Applet/Installer specialized archive formats • 10 Self-extracting archives • 11 Software • 12 Transfer formats • 13 Uncategorized • 14 See also • 15 Links Archiving only (many files => 1 file, no compression attempted) • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • Compression + archiving (Multiple files => 1 file, makes it smaller. See • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • ZPack [Lite] (.zpk) - See • • Diff files (containing only the parts of a file that have changed, so they can be applied to an existing file to update it; used for update distribution and incremental backups) • • • • • • • • • • • • • • • See also Encrypted or cryptographically signed archives • • • File splitting (1 file => multiple files. Most file splitting utilities just produce raw file fragments, and don't have a native file format. But some use a container format, and some create a separate "control" file for metadata.) • • • • Also, the two sorts of Filesyst...

What is a ZIP file? File compression is an important part of the digital workspace. ZIP files use compression to send more data at faster speeds than has ever been possible. This is why ZIP files are such a popular tool for businesses all across the world. But what exactly is a ZIP file? ZIP is a common file format that’s used to compress one or more files together into a single location. This reduces file size and makes it easier to transport or store. A recipient can unzip (or extract) a ZIP file after transport and use the file in the original format. ZIP files work in much the same way as a standard folder on your computer. They contain data and files together in one place. But with zipped files, the contents are compressed, which reduces the amount of data used by your computer. Another way to describe ZIP files is as an archive. The archive contains all the compressed files in one location. So, the ZIP file format is one option to use if you need to make a single file or group of files smaller. So, how can you identify a ZIP archive file? Simple. Whenever you see the extensions .ZIP or .zip at the end of a file name, you’re looking at a ZIP file. The icon that represents the file would also change. Say you have a photo named vacation.jpg. After you zip this photo it now read vacation.zip and have a new icon. Is ZIP different from 7-ZIP or RAR? When you’re researching ZIP files, you may come across the term “7z file” or “7-ZIP.” This is an archiving format that uses a...

The image file formats that are most commonly used on the web are listed below. Abbreviation File format MIME type File extension(s) Summary Animated Portable Network Graphics image/apng .apng Good choice for lossless animation sequences (GIF is less performant). AVIF and WebP have better performance but less broad browser support. Supported: Chrome, Edge, Firefox, Opera, Safari. AV1 Image File Format image/avif .avif Good choice for both images and animated images due to high performance and royalty free image format. It offers much better compression than PNG or JPEG with support for higher color depths, animated frames, transparency, etc. Note that when using AVIF, you should include fallbacks to formats with better browser support (i.e. using the Supported: Chrome, Firefox (still images only: animated images not implemented), Opera, Safari. Graphics Interchange Format image/gif .gif Good choice for simple images and animations. Prefer PNG for lossless and indexed still images, and consider WebP, AVIF or APNG for animation sequences. Supported: Chrome, Edge, Firefox, IE, Opera, Safari. Joint Photographic Expert Group image image/jpeg .jpg, .jpeg, .jfif, .pjpeg, .pjp Good choice for lossy compression of still images (currently the most popular). Prefer PNG when more precise reproduction of the image is required, or WebP/AVIF if both better reproduction and higher compression are required. Support: Chrome, Edge, Firefox, IE, Opera, Safari. Portable Network Graphics image/...