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remove Image meta data from Image in C# [duplicate]

I'm writing a service for a project that's going to handle our image processing. One such process is supposed to strip all metadata from the byte[] provided and return the same image as a byte[].
The method I'm currently working on involves always converting the image to a Bitmap, then converting it back to the original format and returning the data from a MemoryStream.
I haven't been able to test it yet but something tells me I'm going to experience some quality loss.
How can I remove all metadata from any image with a common format?
(bmp, gif, png, jpg, icon, tiff)
Not sure how I can narrow that down any further. Would be nice if I got some feedback regarding the downvotes.

For the lossless formats (except JPEG), your idea of loading it as a bitmap and re-saving is fine. Not sure if .NET natively supports TIFFs (I doubt it does).
For JPEGs, as you suggested there may be quality loss if you're re-compressing the file after decompressing it. For that, you might try the ExifLibrary and see if that has anything. If not, there are command line tools (like ImageMagick) that can strip metadata. (If you use ImageMagick, you're all set, since it supports all of your required formats. The command you want is convert -strip.)
For TIFFs, .NET has built-in TiffBitmapDecoder and ...Encoder classes you might be able to use; see here.
In short, using an external tool like ImageMagick is definitely the easiest solution. If you can't use an external tool, you're almost certainly going to need to special-case the formats that .NET doesn't support natively (and the lossy JPEG).
EDIT: I just read that ImageMagick doesn't do lossless stripping with JPEGs, sorry. I guess using the library I linked above, or some other JPEG library, is the best I can think of.

Load jpg preview from DNG into picturebox

I have written a program that has a feature for viewing images. It works fine for common files types, I simply use a picturebox. But I want to be able to load DNG (Digital Negative) images too.
I don't need to load the whole thing, loading just the baked in jpg preview would be fine, even if not all DNGs have it, I am willing to settle for this to avoid a huge hassle. Plus since DNGs are so big and my program is meant to browse through them quickly this might be best anyway.
I have tried using WindowsAPICodePack.Shell to get the Extra Large Bitmap or Icon from the file. I am already using this for my "explorer" thumbnails. But there is nothing larger than "Large" which I believe is around 256px. I know that the image has something around 1024px jpg preview.
Is there an easy way to get at the jpg preview of a DNG file?

Reading and Writing all JPEG metadata in Silverlight

I've developed a Silverlight application that needs to compress JPEG images on the client. I've been using a library called FJCore to achieve this goal.
One of the biggest issues I'm encountering, however, is the fact that this toolkit requires you to convert the JPEG to a WriteableBitmap first which strips off all the metadata associated with the JPEG such as EXIF, XMP, JFIF, etc. I've modified the source of the FJCore library to persist the EXIF, compress the image, and then reattach the EXIF data. This process works but loses other types of metadata information.
Instead of having to implement a function that saves and writes each different type of metadata that exists for the JPEG format, I am looking for a simplified approach that will allow me to extract all metadata, regardless of type or format, use the FJCore toolkit to compress/resize that image, and then reattach all the previously saved metadata. Some direction or sample code that could help me achieve my goal would be greatly appreciated. Remember, this is a Silverlight application, so those .NET libraries are what I have to work with.
Thank you.

You can do this using FJCore aka ImageTools. All you need to do is add this on line 212:
// Exif. Do something?
headers.Add(header);
https://github.com/briandonahue/FluxJpeg.Core/blob/master/FJCore/Decoder/JpegDecoder.cs
And make sure you copy those headers when resizing:
jpegOut = new DecodedJpeg(
new ImageResizer(jpegIn.Image)
.Resize(320, ResamplingFilters.NearestNeighbor),
jpegIn.MetaHeaders); // Retain EXIF details
Recompile and you should be good to go.

Adding EXIF Info to Images in C#

I want to add basic exif info to images like author,camera model,date etc.Is there a way to do this using the Inbuilt classes without using other external libraries.Does the image formats like JPEG,PNG,TIFF,BMP,GIF Support all EXIF Fields.

System.Drawing allows modifying the image properties with PropertyItems/SetPropertyItem. A sample can be found here.
But this access is quite basic and there are quite a few libraries around (see for instance How to edit EXIF data in .NET). So I wonder if it's worth the trouble.
After all, only JPEG and TIFF files support EXIF metadata according to Wikipedia.

Large file-based bitmap manipulation library

Is there any (preferable open source - but not necessarily) file-based bitmap manipulation library? The basic functionality will include taking a view (a small rectangle) of the bitmap (1-4 GB), changing it and saving it back.
I'm not particularly picky about format (as long as it is lossless): BMP, uncompressed Tiff or Targa will be just fine.
It doesn't have to be all-native code - a wrapper around native dll will be OK although 64-bit version will be very welcome.

Karol, please have a look at it: ImageMagick.NET

FreeImage is all you need.
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