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Pixcel: Convert an image into Excel pixel art

Last week I received an invitation for a social work meeting about "Pixel art in spreadsheets". I thought: "How hard can it be".

Well, it is about 25 lines of C# 9.0 hard! 😀

The code

Using my past experience with EmguCV (OpenCV for .NET) and EPPlus (Excel spreadsheets for .NET), it was quickly built.

var source = args[0];
if (!File.Exists(source)) throw new FileNotFoundException($"Input image not found", source);

var sourceImage = CvInvoke.Imread(source);
var mat = new Mat();
CvInvoke.ResizeForFrame(sourceImage, mat, new Size(64, 64), Inter.Lanczos4, scaleDownOnly: true);
var image = mat.ToImage<Bgr, byte>();

ExcelPackage.LicenseContext = LicenseContext.NonCommercial;
using var package = new ExcelPackage(new FileInfo(source.Replace(Path.GetExtension(source), ".xlsx")));
var worksheet = package.Workbook.Worksheets["Pixcel"] ?? package.Workbook.Worksheets.Add("Pixcel");

for (int y = 1; y <= image.Height; y++)
    worksheet.Row(y).Height = 27.5;

    for (int x = 1; x <= image.Width; x++)
        worksheet.Column(x).Width = 5;
        worksheet.Cells[y, x].Style.Fill.PatternType = ExcelFillStyle.Solid;
        worksheet.Cells[y, x].Style.Fill.BackgroundColor.SetColor(0, image.Data[y-1, x-1, 2], image.Data[y-1, x-1, 1], image.Data[y-1, x-1, 0]);


The result

Demonstration of the Pixcel app.

The source

Liking the result, I christened the project Pixcel and shared the code on GitHub.