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C# lower quality for JPEG image

I'm trying to make an console application in .net core 3, this application can successfully get a bitmap from the computer and send it to another computer. But now I want to lower the quality of the image and send it as a JPEG file.
I have looked on the internet but I'm unable to get it to work. My latest attempt I tried to use the following MSDN website. But with this approach I get stuck at ImageCodecInfo jpgEncoder = GetEncoder(ImageFormat.Jpeg); since my application cannot find GetEncoder. I have found GetEncoder in System.Text.Encoding.Getencoding but here getEncoder doesn't take any parameters.
So my question is which namespace do I have to use or is there another way to lower the quality of an JPEG image?

Here is my functions to compress image as jpeg
public static System.Drawing.Imaging.ImageCodecInfo GetEncoder(System.Drawing.Imaging.ImageFormat format)
{
System.Drawing.Imaging.ImageCodecInfo[] codecs = System.Drawing.Imaging.ImageCodecInfo.GetImageDecoders();
foreach (System.Drawing.Imaging.ImageCodecInfo codec in codecs)
{
if (codec.FormatID == format.Guid)
{
return codec;
}
}
return null;
}
public static byte[] GetCompressedImage(System.Drawing.Image img, long quality)
{
System.Drawing.Imaging.ImageCodecInfo ici = GetEncoder(System.Drawing.Imaging.ImageFormat.Jpeg);
System.Drawing.Imaging.EncoderParameters eps = new System.Drawing.Imaging.EncoderParameters(2);
eps.Param[0] = new System.Drawing.Imaging.EncoderParameter(System.Drawing.Imaging.Encoder.Quality, quality);
eps.Param[1] = new System.Drawing.Imaging.EncoderParameter(System.Drawing.Imaging.Encoder.Compression, (long)System.Drawing.Imaging.EncoderValue.CompressionLZW);
using (MemoryStream ms = new MemoryStream())
{
img.Save(ms, ici, eps);
return ms.ToArray();
}
}

How can I convert a BMP to JPEG without saving to file?

I have a BMP image object which contains a BMP image, how can I convert it to JPEG format without saving to file?
All I need to know is the size of the JPEG file after the conversion, so If I have several BMP images, I want to convert each one of them into a JPEG and then see the size of each one.
How can I do that?
Thanks.

Just save it stream. and look size.
private ImageCodecInfo GetEncoder(ImageFormat format)
{
ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
foreach (ImageCodecInfo codec in codecs)
{
if (codec.FormatID == format.Guid)
{
return codec;
}
}
return null;
}
private void Form1_Load(object sender, EventArgs e)
{
Bitmap bmp1 = new Bitmap(#"C:\Users\ercan.acar\Pictures\Current CR Sticker.PNG");
ImageCodecInfo jpgEncoder = GetEncoder(ImageFormat.Jpeg);
System.Drawing.Imaging.Encoder myEncoder =System.Drawing.Imaging.Encoder.Quality;
EncoderParameters myEncoderParameters = new EncoderParameters(1);
EncoderParameter myEncoderParameter = new EncoderParameter(myEncoder,
50L);
myEncoderParameters.Param[0] = myEncoderParameter;
Stream stream=new MemoryStream();
bmp1.Save(stream, jpgEncoder,myEncoderParameters);
//bmp1.Save(#"C:\Users\ercan.acar\Documents\TestPhotoQualityFifty.jpg",);
var size = stream.Length;
}

How about using a nuget package like Magick.NET or similar.
Why reinventing the wheel and care about encoding, conversion adjustments, optimization if other have done this already for you.

after compressing image it ends up rotated

Hello I have this tutorial to try to get an image compressed, however, when I use a profile photo with my phone(selfie) it just rotates 45 degrees.
What could be happening?
EDIT
I added the code to show you, so it is not necessary to click the link
private void VaryQualityLevel()
{
// Get a bitmap. The using statement ensures objects
// are automatically disposed from memory after use.
using (Bitmap bmp1 = new Bitmap(#"C:\TestPhoto.jpg"))
{
ImageCodecInfo jpgEncoder = GetEncoder(ImageFormat.Jpeg);
// Create an Encoder object based on the GUID
// for the Quality parameter category.
System.Drawing.Imaging.Encoder myEncoder =
System.Drawing.Imaging.Encoder.Quality;
// Create an EncoderParameters object.
// An EncoderParameters object has an array of EncoderParameter
// objects. In this case, there is only one
// EncoderParameter object in the array.
EncoderParameters myEncoderParameters = new EncoderParameters(1);
// Save the bitmap as a JPG file with 10 quality level compression.
myEncoderParameter = new EncoderParameter(myEncoder, 10L);
myEncoderParameters.Param[0] = myEncoderParameter;
bmp1.Save(#"C:\TestPhotoQualityZero.jpg", jpgEncoder, myEncoderParameters);
}
}
This is the other portion of code:
private ImageCodecInfo GetEncoder(ImageFormat format)
{
ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
foreach (ImageCodecInfo codec in codecs)
{
if (codec.FormatID == format.Guid)
{
return codec;
}
}
return null;
}

Images in Hero card inside carousel of bot framework rarely loads

I am using Bot Application Framework of C# to build a skype bot. I do some processing on image and then send it back to user in carousel of hero cards.
https://dev.skype.com/bots
I am following the constraints of the hero card, I am resizing image so that it's resolution is below 1024*1024, it's type is png/jpg and it's size is below 1MB. Also the link to the image is HTTPS://
Images loads in the web chat of https://dev.botframework.com every time, but when I use it on skype PC or Android it loads rarely.
This is how I am making the carousel.
var carousel = context.MakeMessage();
carousel.AttachmentLayout = AttachmentLayoutTypes.Carousel;
carousel.Attachments.Add(GetHeroCard(null, null, "Share this!", new CardImage(url: imageUrl, alt: imageUrl, tap: new CardAction(ActionTypes.ShowImage))));
This is how I am encoding Bitmap object to the png/jpeg format byte array to upload on the blob, from where I get the HTTPS link to the image.
public static byte[] BitmapEncode2Byte(Bitmap bitmap, ImageFormat format)
{
MemoryStream stream = new MemoryStream();
EncoderParameters encoderParameters = new EncoderParameters(1);
encoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);
bitmap.Save(stream, GetEncoder(ImageFormat.Png), encoderParameters);
return stream.ToArray();
}
public static ImageCodecInfo GetEncoder(ImageFormat format)
{
ImageCodecInfo[] codecs = ImageCodecInfo.GetImageEncoders();
foreach (ImageCodecInfo codec in codecs)
{
if (codec.FormatID == format.Guid)
{
return codec;
}
}
return null;
}
Thanks in Advance!

Bmp to jpg/png in C#

Is there any way to convert a bmp image to jpg/png without losing the quality in C#? Using Image class we can convert bmp to jpg but the quality of output image is very poor. Can we gain the quality level as good as an image converted to jpg using photoshop with highest quality?

var qualityEncoder = Encoder.Quality;
var quality = (long)<desired quality>;
var ratio = new EncoderParameter(qualityEncoder, quality );
var codecParams = new EncoderParameters(1);
codecParams.Param[0] = ratio;
var jpegCodecInfo = <one of the codec infos from ImageCodecInfo.GetImageEncoders() with mime type = "image/jpeg">;
bmp.Save(fileName, jpegCodecInfo, codecParams); // Save to JPG

public static class BitmapExtensions
{
public static void SaveJPG100(this Bitmap bmp, string filename)
{
EncoderParameters encoderParameters = new EncoderParameters(1);
encoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);
bmp.Save(filename, GetEncoder(ImageFormat.Jpeg), encoderParameters);
}
public static void SaveJPG100(this Bitmap bmp, Stream stream)
{
EncoderParameters encoderParameters = new EncoderParameters(1);
encoderParameters.Param[0] = new EncoderParameter(System.Drawing.Imaging.Encoder.Quality, 100L);
bmp.Save(stream, GetEncoder(ImageFormat.Jpeg), encoderParameters);
}
public static ImageCodecInfo GetEncoder(ImageFormat format)
{
ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
foreach (ImageCodecInfo codec in codecs)
{
if (codec.FormatID == format.Guid)
{
return codec;
}
}
return null;
}
}

Provided BitmapExtensions by jestro are great, I used them. However would like to show the corrected version - works for Image parent class which is more convenient as I think and provides a way to supply quality:
public static class ImageExtensions
{
public static void SaveJpeg(this Image img, string filePath, long quality)
{
var encoderParameters = new EncoderParameters(1);
encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, quality);
img.Save(filePath, GetEncoder(ImageFormat.Jpeg), encoderParameters);
}
public static void SaveJpeg(this Image img, Stream stream, long quality)
{
var encoderParameters = new EncoderParameters(1);
encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, quality);
img.Save(stream, GetEncoder(ImageFormat.Jpeg), encoderParameters);
}
static ImageCodecInfo GetEncoder(ImageFormat format)
{
ImageCodecInfo[] codecs = ImageCodecInfo.GetImageDecoders();
return codecs.Single(codec => codec.FormatID == format.Guid);
}
}

Fundamentally you won't be able to keep the same quality because jpg is (so far as I'm aware) always lossy even with the highest possible quality settings.
If bit-accurate quality is really important, consider using png, which has some modes which are lossless.

Just want to say that JPEG is by nature a lossy format. So in thoery even at the highest settings you are going to have some information loss, but it depends a lot on the image.But png is lossless.

I am working on an expense report app, and I am really pleased with the default quality settings for JPG (and PNG) when saving from a Bitmap object.
https://msdn.microsoft.com/en-us/library/9t4syfhh%28v=vs.110%29.aspx
Bitmap finalBitmap = ....; //from disk or whatever
finalBitmap.Save(xpsFileName + ".final.jpg", ImageFormat.Jpeg);
finalBitmap.Save(xpsFileName + ".final.png", ImageFormat.Png);
I'm on .NET 4.6...perhaps the quality has improved in subsequent framework releases.

You can try:
Bitmap.InterpolationMode = InterpolationMode.HighQualityBicubic;
and
Bitmap.CompositingQuality = CompositingQuality.HighQuality;
Which does keep the quality fairly high, but not the highest possible.