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Add the bitmap header to the byte array, then create the bitmap file

I have a ByteArray from the camera, it is just a stream and does not have a bitmapheader.

I was looking for a demo, but they are all in C ++.

I am trying to add bitmapheader to my code but with a ParameterException. How to create a bitmap file from ByteArray?

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You cannot create a raster image class directly with raw data that does not have a raster image header. The bitmap header is similar to a bitmap recipe. It includes important information about width, height, bits per pixels, data length, etc., to create the right array for the image.

Creating a bitmap header is pretty simple if you look closely at the bitmap header structure here

But nothing is better than a complete source code example.

I broke them into several parts and commented on each step for you throughout the process. It probably looks a bit overkill, but it will be a good guide for you, I think.

The following is an example of a 2 × 2-pixel 24-bit bitmap (Windows DIB header BITMAPINFOHEADER) with the pixel format RGB24.

BMP file format - Wikipedia

#region Bitmap Making... // BmpBufferSize : a pure length of raw bitmap data without the header. // the 54 value here is the length of bitmap header. byte[] BitmapBytes = new byte[BmpBufferSize + 54]; #region Bitmap Header // 0~2 "BM" BitmapBytes[0] = 0x42; BitmapBytes[1] = 0x4d; // 2~6 Size of the BMP file - Bit cound + Header 54 Array.Copy(BitConverter.GetBytes(BmpBufferSize + 54), 0, BitmapBytes, 2, 4); // 6~8 Application Specific : normally, set zero Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 6, 2); // 8~10 Application Specific : normally, set zero Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 8, 2); // 10~14 Offset where the pixel array can be found - 24bit bitmap data always starts at 54 offset. Array.Copy(BitConverter.GetBytes(54), 0, BitmapBytes, 10, 4); #endregion #region DIB Header // 14~18 Number of bytes in the DIB header. 40 bytes constant. Array.Copy(BitConverter.GetBytes(40), 0, BitmapBytes, 14, 4); // 18~22 Width of the bitmap. Array.Copy(BitConverter.GetBytes(image.Width), 0, BitmapBytes, 18, 4); // 22~26 Height of the bitmap. Array.Copy(BitConverter.GetBytes(image.Height), 0, BitmapBytes, 22, 4); // 26~28 Number of color planes being used Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 26, 2); // 28~30 Number of bits. If you don't know the pixel format, trying to calculate it with the quality of the video/image source. if (image.PixelFormat == System.Drawing.Imaging.PixelFormat.Format24bppRgb) { Array.Copy(BitConverter.GetBytes(24), 0, BitmapBytes, 28, 2); } // 30~34 BI_RGB no pixel array compression used : most of the time, just set zero if it is raw data. Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 30, 4); // 34~38 Size of the raw bitmap data ( including padding ) Array.Copy(BitConverter.GetBytes(BmpBufferSize), 0, BitmapBytes, 34, 4); // 38~46 Print resolution of the image, 72 DPI x 39.3701 inches per meter yields if (image.PixelFormat == System.Drawing.Imaging.PixelFormat.Format24bppRgb) { Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 38, 4); Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 42, 4); } // 46~50 Number of colors in the palette Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 46, 4); // 50~54 means all colors are important Array.Copy(BitConverter.GetBytes(0), 0, BitmapBytes, 50, 4); // 54~end : Pixel Data : Finally, time to combine your raw data, BmpBuffer in this code, with a bitmap header you've just created. Array.Copy(BmpBuffer as Array, 0, BitmapBytes, 54, BmpBufferSize); #endregion - bitmap header process #endregion - bitmap making process
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Use the System.Drawing.Bitmap class

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It will work

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 using System; using System.IO; using System.Drawing;

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 public Image ByteArrayToImage(byte[] byteArrayIn) { MemoryStream ms = new MemoryStream(byteArrayIn); Image img = Image.FromStream(ms); return img; }
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