Updated lightning demo to remove System.Drawing (sipsorcery-org#1386)

* wip: Lighnting demo adjustments for k8s deployment.

* Swapped out System.Drawing and swtich to asp.net web socket server.

* Removed redundant code wired back up transparency logic.

* Added docker build file and instructions to readme.

* Fixed docker image name.

Author: sipsorcery

examples/WebRTCLightningExamples/AnnotatedBitmapService.old..cs

@@ -0,0 +1,183 @@
+//-----------------------------------------------------------------------------
+// Filename: AnnotatedBitmapService.cs
+//
+// Description: Service class to annotate bitmaps. The original purpose was
+// to serve as the video source on a WebRTC connection.
+//
+// Author(s):
+// Aaron Clauson (aaron@sipsorcery.com)
+// 
+// History:
+// 25 Feb 2025	Aaron Clauson	Created, Dublin, Ireland.
+//
+// License: 
+// BSD 3-Clause "New" or "Revised" License, see included LICENSE.md file.
+//-----------------------------------------------------------------------------
+
+using QRCoder;
+using System.Drawing.Drawing2D;
+using System.Drawing;
+using System;
+using Microsoft.Extensions.Logging;
+using System.Collections.Concurrent;
+
+namespace demo;
+
+public interface IAnnotatedBitmapGenerator
+{
+    Bitmap? GetAnnotatedBitmap(PaidVideoFrameConfig frameConfig);
+}
+
+public class AnnotatedBitmapService : IAnnotatedBitmapGenerator
+{
+    private const float TEXT_SIZE_PERCENTAGE = 0.035f;       // Height of text as a percentage of the total image height.
+    private const float TEXT_OUTLINE_REL_THICKNESS = 0.02f;  // Black text outline thickness is set as a percentage of text height in pixels.
+    private const int TEXT_MARGIN_PIXELS = 5;
+    private const int POINTS_PER_INCH = 72;
+    private const int BORDER_WIDTH = 5;
+    private const int QR_CODE_DIMENSION = 200;
+
+    private readonly ConcurrentDictionary<string, Lazy<Bitmap>> _qrCodeCache = new();
+
+    private readonly ILogger _logger;
+
+    public AnnotatedBitmapService(ILogger<AnnotatedBitmapService> logger)
+    {
+        _logger = logger;
+    }
+
+    public Bitmap? GetAnnotatedBitmap(PaidVideoFrameConfig frameConfig)
+    {
+        try
+        {
+            unsafe
+            {
+                string imagePath = frameConfig.ImagePath;
+                using (Bitmap baseBitmap = new Bitmap(imagePath))
+                {
+                    var baseImage = baseBitmap.Clone() as Image;
+                    if (baseImage != null)
+                    {
+                        ApplyFilters(
+                            baseImage,
+                            DateTime.UtcNow.ToString("dd MMM yyyy HH:mm:ss:fff"),
+                            frameConfig.Title,
+                            frameConfig.BorderColour,
+                            frameConfig.Opacity,
+                            frameConfig.LightningPaymentRequest);
+
+                        return baseImage as Bitmap;
+                    }
+                }
+            }
+        }
+        catch (Exception excp)
+        {
+            _logger.LogError("Exception GetAnnotatedBitmap. " + excp);
+        }
+
+        return null;
+    }
+
+    private void ApplyFilters(Image image, string timeStamp, string title, Color borderColor, int transparency, string? lightningPaymentRequest)
+    {
+        int pixelHeight = (int)(image.Height * TEXT_SIZE_PERCENTAGE);
+
+        using Graphics g = Graphics.FromImage(image);
+        g.SmoothingMode = SmoothingMode.AntiAlias;
+        g.InterpolationMode = InterpolationMode.HighQualityBicubic;
+        g.PixelOffsetMode = PixelOffsetMode.HighQuality;
+
+        // Draw border.
+        using (var pen = new Pen(borderColor, BORDER_WIDTH))
+        {
+            g.DrawLine(pen, new Point(0, 0), new Point(0, image.Height));
+            g.DrawLine(pen, new Point(0, 0), new Point(image.Width, 0));
+            g.DrawLine(pen, new Point(0, image.Height), new Point(image.Width, image.Height));
+            g.DrawLine(pen, new Point(image.Width, 0), new Point(image.Width, image.Height));
+        }
+
+        // Add transparency.
+        using (Brush brush = new SolidBrush(Color.FromArgb(transparency, Color.Gray)))
+        {
+            g.FillRectangle(brush, new Rectangle(0, 0, image.Width, image.Height));
+        }
+
+        // Add header and footer text.
+        using (StringFormat format = new StringFormat())
+        {
+            format.LineAlignment = StringAlignment.Center;
+            format.Alignment = StringAlignment.Center;
+
+            using (Font f = new Font("Tahoma", pixelHeight, GraphicsUnit.Pixel))
+            {
+                using (var gPath = new GraphicsPath())
+                {
+                    float emSize = g.DpiY * f.Size / POINTS_PER_INCH;
+                    if (title != null)
+                    {
+                        gPath.AddString(title, f.FontFamily, (int)FontStyle.Bold, emSize, new Rectangle(0, TEXT_MARGIN_PIXELS, image.Width, pixelHeight), format);
+                    }
+
+                    gPath.AddString(timeStamp /* + " -- " + fps.ToString("0.00") + " fps" */, f.FontFamily, (int)FontStyle.Bold, emSize, new Rectangle(0, image.Height - (pixelHeight + TEXT_MARGIN_PIXELS), image.Width, pixelHeight), format);
+                    g.FillPath(Brushes.White, gPath);
+                    g.DrawPath(new Pen(Brushes.Black, pixelHeight * TEXT_OUTLINE_REL_THICKNESS), gPath);
+                }
+            }
+        }
+
+        if (!string.IsNullOrWhiteSpace(lightningPaymentRequest))
+        {
+            using var qrCode = GetCachedQRCode(lightningPaymentRequest);
+
+            int xCenter = (image.Width - QR_CODE_DIMENSION) / 2;
+            int yCenter = (image.Height - QR_CODE_DIMENSION) / 2;
+            Rectangle dstRect = new Rectangle(xCenter, yCenter, QR_CODE_DIMENSION, QR_CODE_DIMENSION);
+            g.DrawImage(qrCode, dstRect);
+        }
+        else
+        {
+            ClearQRCodeCache();
+        }
+    }
+
+    private Bitmap GetCachedQRCode(string lightningPaymentRequest)
+    {
+        if (string.IsNullOrWhiteSpace(lightningPaymentRequest))
+        {
+            throw new ArgumentException("Payment request must be provided", nameof(lightningPaymentRequest));
+        }
+
+        // Use Lazy to ensure only one QR code is generated per unique payment request.
+        var lazyQr = _qrCodeCache.GetOrAdd(lightningPaymentRequest, key =>
+            new Lazy<Bitmap>(() => GenerateQRCode(key))
+        );
+
+        // Clone the bitmap to ensure thread safety.
+        return (Bitmap)lazyQr.Value.Clone();
+    }
+
+    private void ClearQRCodeCache()
+    {
+        foreach (var key in _qrCodeCache.Keys)
+        {
+            if (_qrCodeCache.TryRemove(key, out var lazyBitmap))
+            {
+                if (lazyBitmap.IsValueCreated)
+                {
+                    lazyBitmap.Value.Dispose();
+                }
+            }
+        }
+    }
+
+    private Bitmap GenerateQRCode(string lightningPaymentRequest)
+    {
+        using QRCodeGenerator qrGenerator = new();
+        using QRCodeData qrCodeData = qrGenerator.CreateQrCode(lightningPaymentRequest, QRCodeGenerator.ECCLevel.Q);
+        using QRCode qrCode = new(qrCodeData);
+
+        Bitmap qrBitmap = qrCode.GetGraphic(20);
+        return qrBitmap;
+    }
+}

examples/WebRTCLightningExamples/README.md

@@ -142,3 +142,29 @@ docker logs -f bitcoind
  - **Connection Issues:** Verify that the `appSettings.json`, or `appSettings.Development.json`, file has the correct LND connection details.
 
  - **Payment Not Triggering Video Updates:** Ensure the payment is confirmed and the demo application is correctly processing payment events.
+
+## Docker Image
+
+### Build
+
+`C:\dev\sipsorcery\examples\WebRTCLightningExamples> docker build -t webrtclightningdemo --progress=plain -f Dockerfile .
+
+### Run
+
+```
+set LND_URL="use real value"
+set LND_MACAROON_HEX="use real value"
+set LND_CERTIFICATE_BASE64="use real value"
+```
+
+`docker run --rm -it -p 8080:8080 -e ASPNETCORE_URLS="http://0.0.0.0:8080" -e Lnd__Url="%LND_URL%" -e Lnd__MacaroonHex="%LND_MACAROON_HEX%" -e Lnd__CertificateBase64="%LND_CERTIFICATE_BASE64%" webrtclightningdemo`
+
+### From DokcerHub
+
+`docker run --rm -it -p 8080:8080 -e ASPNETCORE_URLS="http://0.0.0.0:8080" -e Lnd__Url="%LND_URL%" -e Lnd__MacaroonHex="%LND_MACAROON_HEX%" -e Lnd__CertificateBase64="%LND_CERTIFICATE_BASE64%" -e WAIT_FOR_ICE_GATHERING_TO_SEND_OFFER="True" -e STUN_URL="stun:stun.cloudflare.com" sipsorcery/webrtclightningdemo`
+
+### Troubleshooting
+
+`docker run --rm -it -p 8080:8080 -e ASPNETCORE_URLS="http://0.0.0.0:8080" -e Lnd__Url="%LND_URL%" -e Lnd__MacaroonHex="%LND_MACAROON_HEX%" -e Lnd__CertificateBase64="%LND_CERTIFICATE_BASE64%" --entrypoint "/bin/bash" webrtclightningdemo`
+
+If there is a missing font exception check the `/usr/share/fonts/truetype/msttcorefonts` directory.