Emgucv Image to texture2d on Unity - unity3d

Question

public class testEmguCV : MonoBehaviour
{
private Capture capture;
void Start()
{
capture = new Capture();
}
void Update()
{
Image<Gray, Byte> currentFrame = capture.QueryGrayFrame();
Bitmap bitmapCurrentFrame = currentFrame.ToBitmap();
MemoryStream m = new MemoryStream();
bitmapCurrentFrame.Save(m, bitmapCurrentFrame.RawFormat);
Texture2D camera = new Texture2D(400, 400);
if (currentFrame != null)
{
camera.LoadImage(m.ToArray());
renderer.material.mainTexture = camera;
}
}
}
I used above code to convert between camera feed from emgucv camera to texture2d in unity but i am having problem with bitmapCurrentFrame.Save(m, bitmapCurrentFrame.RawFormat);
it is giving following errors
ArgumentNullException: Argument cannot be null. Parameter name:
encoder System.Drawing.Image.Save (System.IO.Stream stream,
System.Drawing.Imaging.ImageCodecInfo encoder,
System.Drawing.Imaging.EncoderParameters encoderParams)
System.Drawing.Image.Save (System.IO.Stream stream,
System.Drawing.Imaging.ImageFormat format) (wrapper
remoting-invoke-with-check) System.Drawing.Image:Save
(System.IO.Stream,System.Drawing.Imaging.ImageFormat)
WebcamUsingEmgucv.Update () (at Assets/WebcamUsingEmgucv.cs:51)
After several hours of thinking and searching i dont know what is going on please help

Answer 1

I used your example in our project, thanks! But i modified it to :
void Update()
{
if(capture == null)
{
Debug.LogError("Capture is null");
return;
}
Image<Gray, Byte> currentFrame = capture.QueryGrayFrame();
MemoryStream m = new MemoryStream();
currentFrame.Bitmap.Save(m, currentFrame.Bitmap.RawFormat);
Texture2D camera = new Texture2D(400, 400);
if (currentFrame != null)
{
camera.LoadImage(m.ToArray());
renderer.material.mainTexture = camera;
}
}
And it is work! Fps average ~30-35. Good luck!

Answer 2

Try to use this:
https://github.com/neutmute/emgucv/blob/3ceb85cba71cf957d5e31ae0a70da4bbf746d0e8/Emgu.CV/PInvoke/Unity/TextureConvert.cs
it has something like this:
public static Texture2D ImageToTexture2D<TColor, TDepth>(Image<TColor, TDepth> image, bool correctForVerticleFlip)
where TColor : struct, IColor
where TDepth : new()
{
Size size = image.Size;
if (typeof(TColor) == typeof(Rgb) && typeof(TDepth) == typeof(Byte))
{
Texture2D texture = new Texture2D(size.Width, size.Height, TextureFormat.RGB24, false);
byte[] data = new byte[size.Width * size.Height * 3];
GCHandle dataHandle = GCHandle.Alloc(data, GCHandleType.Pinned);
using (Image<Rgb, byte> rgb = new Image<Rgb, byte>(size.Width, size.Height, size.Width * 3, dataHandle.AddrOfPinnedObject()))
{
rgb.ConvertFrom(image);
if (correctForVerticleFlip)
CvInvoke.cvFlip(rgb, rgb, FLIP.VERTICAL);
}
dataHandle.Free();
texture.LoadRawTextureData(data);
texture.Apply();
return texture;
}
else //if (typeof(TColor) == typeof(Rgba) && typeof(TDepth) == typeof(Byte))
{
Texture2D texture = new Texture2D(size.Width, size.Height, TextureFormat.RGBA32, false);
byte[] data = new byte[size.Width * size.Height * 4];
GCHandle dataHandle = GCHandle.Alloc(data, GCHandleType.Pinned);
using (Image<Rgba, byte> rgba = new Image<Rgba, byte>(size.Width, size.Height, size.Width * 4, dataHandle.AddrOfPinnedObject()))
{
rgba.ConvertFrom(image);
if (correctForVerticleFlip)
CvInvoke.cvFlip(rgba, rgba, FLIP.VERTICAL);
}
dataHandle.Free();
texture.LoadRawTextureData(data);
texture.Apply();
return texture;
}
//return null;
}
If You don't want tuo use an InterOp You can use also something like
cameraframe.Convert<Rgb,byte>().Data.Cast<byte>().ToArray<byte>()
and use it instead of section using interOp
Both solutions worked for me. Just remember to destroy the texture before replacing it. I had memory leak issues before I did that.