Is there a class in C# library which does LZW compression on TIFF images. I know there is a compression scheme inviolving LZW being present, but using that doesnt decrease the file size whatsoever. Is there any thing that Im assuming wrong? Please correct me if I am.
Because LZW is loseless compression, you can compress TIFF images or any other kind of data using the same way. In C# you can use the SharpLZW library.
--EDIT (1)--
If you want to produce a TIFF file with embedded LZW compression respecting the TIFF specification look at section 13 of the specification.
--EDIT (2)--
There was a patent but it is now expired.
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I have PDF compressed with JBIG2. How can I recompress it to JPEG or any other compression algorithms?
I want to use open source solution like Itextsharp/PDFSharp or any other c# .net open source project.
You would need to decompress the image data, convert it from 1 bit per component to 8 bits per component, then apply JPEG compression.
But it's a bit unusual to convert monochrome images to color. This should increase the size actually. JBIG2 is pretty good for many monochrome images, why do you want to use JPEG compression on it?
I was reading about image compression, but found that the encoder for c# is lossy, is there any way to make a lossless function compressor in c#? I could only find the lossy option ( https://learn.microsoft.com/en-us/dotnet/api/system.drawing.imaging.encoderparameters?view=netframework-4.8 )
Please have a look at the Fo-Dicom library at GitHub. It is an open-source library for the use in medical imaging. They have implemented all the lossless JPEG algorithms like Jpeg Lossless, Jpeg-LS and Jpeg2000:
https://github.com/fo-dicom/fo-dicom/tree/4562544b8742c78b7b6dd49f1e47bc7952690ee5
Fo-Dicom in itself uses the Health-Efferent library (also open source), which is written in C++, but C# wrappers are implemented:
https://github.com/Efferent-Health/fo-dicom.Codecs
Use PNG to have lossless image compression in .NET.
Because PNG is by design (and also standardized by W3C and IETF) is lossless.
For more information, visit official documentation on encoding and decoding PNG using .NET:
https://learn.microsoft.com/en-us/dotnet/framework/wpf/graphics-multimedia/how-to-encode-and-decode-a-png-image
And for reference, this is the official PNG standard: https://www.rfc-editor.org/rfc/rfc2083
Update 1:
I added clarification of supported lossless image compression in .NET.
JPEG compression is by design lossy in most cases ("acceptably so") but a lossless standard does exist; you might find that some of the c# snippets on this site get you towards your goal:
https://www.graphicsmill.com/docs/gm/applying-lossless-jpeg-transforms.htm
This is a question about TIFF and compression. I have hundreds of LZW compressed tiff images. I wonder, is it possible to convert those to CCITT T.6? Is there some API? Please help.
LZW compression can be used to compress almost any image. CCITT T.6 can compress only bilevel (black and white) images.
If your images are bilevel ones and they are compressed with LZW compression then you can recompress them using tiffcp utility (comes with LibTiff.Net library, free, source code available).
If your images are full-color ones then you will have to convert them to bilevel first. One of my answers contains sample code for such conversion.
JPEG-LS is a lossless image compression algorithm for continuous-tone images. Images compressed using JPEG-LS results to a file with an extension of ".jls".
How may I access this file using C#, or how may I access its bitstream, so that I may further compress it?
I tried using Bitmap in C#, storing it in a Bitmap, but it does not support it.
I tried opening it through notepad, but its been encoded in some unknown format.
You could try CharLS, an open-source JPEG-LS library.
How to compress and uncompress JPEG using lossless method?
It's specified in the JPEG standard but few encoders support it. Use a lossless image format like PNG.
The Intel IPP contains a codec that supports the lossless version of the JPEG standard. Certain medical devices use this format and probably nobody else in the world.
Using the normal JPEG you can set the quality to 100% (or 1.0), but I don't think you'll ever get completely lossless compression because this is lossy by definition.
There is Lossless JPEG but it's a completely different algorithm, but I can't find any evidence of how well it's supported.
If you have any choice in the matter use png instead.