How can I convert a BITMAP in byte array format to JPEG format using .net 2.0?
What type of byte[] do you mean? The raw file-stream data? In which case, how about something like (using System.Drawing.dll in a client application):
using(Image img = Image.FromFile("foo.bmp"))
{
img.Save("foo.jpg", ImageFormat.Jpeg);
}
Or use FromStream with a new MemoryStream(arr) if you really do have a byte[]:
byte[] raw = ...todo // File.ReadAllBytes("foo.bmp");
using(Image img = Image.FromStream(new MemoryStream(raw)))
{
img.Save("foo.jpg", ImageFormat.Jpeg);
}
If it is just a buffer of raw pixel data, and not a complete image file(including headers etc., such as a JPEG) then you can't use Image.FromStream.
I think what you might be looking for is System.Drawing.Bitmap.LockBits, returning a System.Drawing.Imaging.ImageData; this provides access to reading and writing the image's pixels using a pointer to memory.
public static Bitmap BytesToBitmap(byte[] byteArray)
{
using (MemoryStream ms = new MemoryStream(byteArray))
{
Bitmap img = (Bitmap)Image.FromStream(ms);
return img;
}
}
Related
I need to convert a JBIG1 image to another image format, such as JPEG or PNG, but I can't seem to find anything related to this.
This JBIG1 image is received encoded in Base64.
I've tried using System.Drawing in .NET to accomplish this, but a "System.ArgumentException: Parameter is not valid" exception is thrown on calling Image.FromStream() using the JBIG1 byte array data.
See code below:
byte[] binData = ConvertFromBase64StringToArray("BASE64 ENCODED JBIG1 IMAGE GOES HERE");
Image img = binData.ConvertToImage();
img.Save("C:/Images/converted-from-jbig.jpeg", System.Drawing.Imaging.ImageFormat.Jpeg);
Functions used:
public static byte[] ConvertFromBase64StringToArray(string base64String)
{
byte[] data = Convert.FromBase64String(base64String);
using (var stream = new MemoryStream(data, 0, data.Length))
{
data = stream.ToArray();
}
return data;
}
public static Image ConvertToImage(this byte[] byteArrayIn)
{
var ms = new MemoryStream(byteArrayIn);
Image returnImage = Image.FromStream(ms); //exception thrown in this line
return returnImage;
}
Does anyone have any knowledge to share about this topic?
You'll probably need a third party library to work with JBig files. It looks like https://github.com/dlemstra/Magick.NET has support for that.
I'm looking for the conventer from normal image in C# to AMF3 ByteArray. The image format is JPG, I'm using FluorineFX library to serialize and de-serliazize AMF3 Data.
I need to get image ByteArray in C# from JPG because I'm using this to my flash game, and I don't know how to serialize image to AMF3 ByteArray. There isn't much info on FluorineFX neither AMF3 C# ByteArray.
According to old FluorineFX Documentation if you want to convert image to byte array you need to use byte[] (variable types ending with [] are arrays) or FluorineFx.AMF3.ByteArray.
byte[] Example code:
public byte[] imageToByteArray(System.Drawing.Image imageIn)
{
MemoryStream ms = new MemoryStream();
imageIn.Save(ms,System.Drawing.Imaging.ImageFormat.Gif);
return ms.ToArray();
}
public Image byteArrayToImage(byte[] byteArrayIn)
{
MemoryStream ms = new MemoryStream(byteArrayIn);
Image returnImage = Image.FromStream(ms);
return returnImage;
}
I'm using this function to convert base64 to image.
public Image Base64ToImage(string base64String)
{
// Convert Base64 String to byte[]
byte[] imageBytes = Convert.FromBase64String(base64String);
using (var ms = new MemoryStream(imageBytes, 0,imageBytes.Length))
{
// Convert byte[] to Image
ms.Write(imageBytes, 0, imageBytes.Length);
//Image image = Image.FromStream(ms, true);
Image image = Image.FromStream(ms,true,true);
return image;
}
}
but it is not working. please help me.
I don't thik the ms write call is needed here.
using (var ms = new MemoryStream(imageBytes, 0,imageBytes.Length))
{
// Convert byte[] to Image
ms.Write(imageBytes, 0, imageBytes.Length);
Your are efectively constructing the stream from your byteArray so the ms.Write call will append the data twice in the stream. This might cause issues for your Image object. Either use the default constructor for the stream or delete the Write and test again.
Edit:
Zey deleted his answer but i think he had a good point in there. You might consider dropping the using block as well. My memory might fail me but i think Image objects need the source stream to be kept open. Dispose the Image object when not needed anymore.
I have the following codes to convert an image(bitmap) to byte array:
public byte[] ConvertImageToByteArray(Image imageToConvert, ImageFormat formatOfImage)
{
byte[] Ret;
try
{
using (MemoryStream ms = new MemoryStream())
{
imageToConvert.Save(ms, formatOfImage);
Ret = ms.ToArray();
}
}
catch (Exception)
{
throw;
}
return Ret;
}
and Convert byte array back to image(bitmap):
public Bitmap ConvertByteArrayToImage(byte[] myByteArray)
{
Image newImage;
using (MemoryStream ms = new MemoryStream(myByteArray, 0, myByteArray.Length))
{
ms.Write(myByteArray, 0, myByteArray.Length);
newImage = Image.FromStream(ms, true);
}
return newImage;
}
Here's my Main Program:
byte[] test = ConvertImageToByteArray(Image.FromFile("oldImage.bmp"), ImageFormat.Bmp);
Bitmap bmp = ConvertByteArrayToImage(test);
bmp.Save("newImage.bmp");
But when I compare both of the image files(old & new bitmap images), their checksum appeared to be different. Any reason for that happening? How to fix it to maintain its integrity?
Basically, there are many ways an identical image can be encoded in a BMP file. If I try your example on a random image I found, I see the .NET Bitmap class saves the file without filling the biSizeImage field in the BITMAPINFOHEADER structure in the BMP header (but the original image produced by IrfanView has it filled), which is a completely correct and documented possibility. (“This may be set to zero for BI_RGB bitmaps.”)
And this is definitely not the only variable thing in the BMP format. For instance, there are multiple possible orderings of pixel data in the image (top-to-bottom, bottom-to-top), specified in the header. (“If biHeight is positive, the bitmap is a bottom-up DIB and its origin is the lower-left corner. If biHeight is negative, the bitmap is a top-down DIB and its origin is the upper-left corner.”)
So, if you receive any BMP file from a source not under your control and really need to produce an image using exactly the same BMP variant, you have a lot work to do, and I don’t think you could use the standard .NET helper classes for that.
See also this question: Save bitmap to file has zero in image size field
After chatting a bit, you solution comes down to reading and writing bytes, take the image object out the equation and just deal with the raw bytes.
To read the file:
MemoryStream ms = new MemoryStream(File.ReadAllBytes("filename"));
To write the file:
File.WriteAllBytes("outputfile", ms.ToArray());
Is there a way in C# to do this conversion and back?
I have a WPF app which has a Image control. I'm trying to save the image in that control to a SQL Database.
In my Entity Model, the datatype of the picture column in my database is a byte[]. So I found a method to convert a System.Drawing.Image to a byte[] and back. But I haven't found a method to convert from System.Windows.Controls.Image to a byte[].
So that's why I now need to do the above conversion.
If you have a byte array that represents a file that WPF can decode (bmp, jpg, gif, png, tif, ico), you can do the following:
BitmapSource LoadImage(Byte[] imageData)
{
using (MemoryStream ms = new MemoryStream(imageData))
{
var decoder = BitmapDecoder.Create(ms,
BitmapCreateOptions.PreservePixelFormat, BitmapCacheOption.OnLoad);
return decoder.Frames[0];
}
}
Likewise, to convert it back, you can do the following:
byte[] SaveImage(BitmapSource bitmap)
{
using (MemoryStream ms = new MemoryStream())
{
var encoder = new BmpBitmapEncoder();
encoder.Frames.Add(BitmapFrame.Create(bitmap));
encoder.Save(ms);
return ms.GetBuffer();
}
}
Well, one is an image and one is a control that shows an image, so I don't think that there's a conversion between the two. But, you could set the Source of the ...Controls.Image to be your ...Drawing.Image.
Edit based on update
Does this do what you need - http://msdn.microsoft.com/en-us/library/ms233764%28VS.100%29.aspx