Urgent help needed!!! Problem with loading byte array into bitmap object

Question

Hi all,

I don't know if this is the correct forum for uploading this question, i found no other.

I have the following problem.
I'm using a check reader which also scans the check.
The scanner api dll has a certain function for saving the image directly to disk. If I use this function all is ok.
But the problem is that I need not to save this image to disk because i have to save it in a sql database.
So, reading the documentation, i realized that after the scanner scans the check, it gives me a pointer to the image buffer.
So, what I do is load this buffer into a bitmap object. This way is fine for me, then I can save the image to the database from the bitmap object.

But... here is my problem, if I test saving this bitmap, the I open it, it's the same as the one saved by the dll function, but it's colors are not the same.
I enclose you here both images (I uploaded them in jpg format but i also updoaded them in bmp format)

The one that is ok (saved by the dll) -> http://www.sistemasplenario.com.ar/dllbmp.jpg    |     http://www.sistemasplenario.com.ar/dllbmp.bmp
The one that is bad(saved by me) -> http://www.sistemasplenario.com.ar/mybmp.jpg    |     http://www.sistemasplenario.com.ar/mybmp.bmp

I enclose here the code I use for locking the bits and asigning them to the bitmap object:

img.tImageSize  -> is the size of the image

img.lpImage -> is the pointer to the image buffer

-------------------------------------------------------------------------------

Dim

 

buffer(img.tImageSize) As Byte

System.Runtime.InteropServices.Marshal.Copy(img.lpImage, buffer, 0, img.tImageSize)

 

Dim bmp As New Bitmap(img.lWidth, img.lHeight, img.lWidth * 4, Imaging.PixelFormat.Format24bppRgb, buffer(0))

 

Dim rect As New Rectangle(0, 0, bmp.Width, bmp.Height)

 

Dim bmpData As System.Drawing.Imaging.BitmapData = bmp.LockBits(rect, Drawing.Imaging.ImageLockMode.ReadWrite, bmp.PixelFormat)

 

Dim ptr As IntPtr = bmpData.Scan0

System.Runtime.InteropServices.Marshal.Copy(buffer, 0, ptr, img.tImageSize)

bmp.UnlockBits(bmpData)

bmp.Save(

"C:\mybmp.bmp")


Thanks in advance

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Antonio Briones Sistemas Plenario vb and c# .net developer for win and web forms. I work for

Answer 1

As I can see you can Speak Spanish, so... Why are you using english in a Spanish forum?
I think would be better to use Spanish, some people here are good at programming but they can't understand English...

Answer 2

Es verdad!, pasa que siempre postee en los foros en ingles, pensaba que este era en ingles tambien!, de cualquier forma ya solucione el problema de otra forma, uso la funcion de la dll para guardar la imagen en un directorio temporal y luego la levanto.
Gracias igual!

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Antonio Briones Sistemas Plenario vb and c# .net developer for win and web forms. I work for