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Questions tagged [lossless]

Lossless data compression is a class of data compression algorithms that allows the original data to be perfectly reconstructed from the compressed data.

Lossless data compression is a class of data compression algorithms that allows the original data to be perfectly reconstructed from the compressed data.

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Lossless video trimming with milliseconds using FFMPEG

I've spent a few weeks going through and testing all the answers on here for lossless cutting using FFMPEG on Android. No matter what I try I always get loss. In the app we're building we need to be millisecond precise. I've tried so many variations…
AngryCubeDev
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Lossless JPG crop without losing EXIF, on Android

I implement a crop feature on an Android app for JPG files, with very strict requirements: The EXIF must be kept. The crop must be lossless (as a consequence the crop can only be done at certain places, that's OK). App size is very strict, so any…
Nicolas Raoul
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How to compress subpixel text bitmap

Recently, I am doing jobs about Windows clearType text compression; Windows text font use sub-pixel rendering tech which making the text font edge full of mess colors, like below. I have try the jpeg, zstd, lz4, the compression ratio of them cannot…
haie1011
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Reduce the number of rows in a binary table

I have a table with a 38 bit binary string at every address. I am trying to figure out what would be the best way of reducing the depth of the table? Say for example that I have 1024 addresses and I want to reduce it to about 100 addresses, such…
user439569
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Jpeg "Nondifferential Huffman coding" processes

I have a question regarding specific processes in JPEG: processes marked with SOF0 - SOF3 are defined by standard as Nondifferential Huffman coding frames what does it mean? For example, SOF7 is defined as differential lossless with Huffman…
Artyshan
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Why isn't lossless compression automatic on computers?

I was just wondering what could be the impact if, say, Microsoft decided to automaticly "lossless" compress every single file saved in a computer. What are the pros? The cons? Is it feasible?
Raphael Moraglia
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Compress DICOM file with DCMTK (C++)

damn i'm very frustated... Following the example in this page http://support.dcmtk.org/docs/mod_dcmjpeg.html, I have written a C++ program to decompress a JPEG-compressed DICOM image file Now I want to do the vice versa, from uncompressed to…
GiordiX
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How to read image data from .cr2 in C++?

How to read image data from .cr2 (raw image format by Canon) in C++? The only one operation I need to perform is to read pixel data of .cr2 file directly if it is possible, otherwise I would like to convert it to any loss-less image and read its…
Pavel
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Make an image progressive and lossless with .NET

I need a DLL, or .NET code without an exe file, to make a progressive lossless jpeg (.jpg, not JPEG 2000 or JPEG-LS that are not supported in several browsers) because I'm using a shared hosting where I can't execute .exe files. I'm using freeImage…
Álvaro López
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Lossless jpeg batch crop on Linux

I need to crop a number of images in jpeg format by 20 pixels on the right side losslessly on Linux. I checked jpegtran, but it needs the file size in pixels before cropping, and I don't know how to build a batch file with that. How can I losslessly…
user2708058
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8/16/32/64 bit aligned lossless compression of .bss and .data for embedded system core dump

I'm looking for a fast / lossless / fix spaced compression algorithm for the following task. I have an embedded system. Low memory / flash resource. I want to generate a core dump for it and store the result in flash and / or suck it out over a slow…
John Carter
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Reading DICOM 1.2.840.10008.1.2.4.70

I have a problem when reading DICOM file. This is the format 1.2.840.10008.1.2.4.70(Process 14 with a first-order prediction (Selection Value 1). I write my own software. Here is result of my work. I also give you a .dcm file. What can be wrong…
user1677686
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Multiframe Dicom file not readable by some viewers

I have developed a program in C++ that works in 2 major steps : extract frames from a video with ffmpeg and convert them to jpeg ffmpeg -i videofile.mp4 -q:v 1 -r desired_framerate tmp_04%d.jpeg create a multiframe Dicom file from those jpeg…
PizzaPasNette
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Ffmpeg. Best way to rip dvd and convert mov into lossless mp4 that is playable in QuickTime on Mac?

I’ve been ripping my collection of anime dvds with MakeMKV and converting them into .mp4 files using Ffmpeg. There are a couple things I need help with- I’ve noticed that using the command ffmpeg -i input.mkv output.mp4 works in converting the mkv…
Liam
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splitting a flac image into tracks

This is a follow up question to Flac samples calculation. Do I implement the offset generated by that formula from the beginning of the file or after the metadata where the stream starts (here)? My goal is to programmatically divide the file myself…
Cooter
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