jellyfin/MediaBrowser.Server.Implementations/Photos/StripCollageBuilder.cs

using ImageMagickSharp;
using MediaBrowser.Common.Configuration;
using MediaBrowser.Server.Implementations.Drawing;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;

namespace MediaBrowser.Server.Implementations.Photos
{
    public class StripCollageBuilder
    {
        private readonly IApplicationPaths _appPaths;

        public StripCollageBuilder(IApplicationPaths appPaths)
        {
            _appPaths = appPaths;
        }

        public Stream BuildThumbCollage(IEnumerable<string> paths, string text, int width, int height)
        {
            using (var wand = BuildThumbCollageWand(paths, text, width, height))
            {
                return DynamicImageHelpers.GetStream(wand, _appPaths);
            }
        }

        private IEnumerable<string> ProjectPaths(IEnumerable<string> paths, int count)
        {
            var clone = paths.ToList();
            var list = new List<string>();

            while (list.Count < count)
            {
                list.AddRange(clone);
            }

            return list.Take(count);
        }

        private MagickWand BuildThumbCollageWand(IEnumerable<string> paths, string text, int width, int height)
        {
            using (var wandImages = new MagickWand(ProjectPaths(paths, 8).ToArray()))
            {
                var wand = new MagickWand(width, height);
                wand.OpenImage("gradient:#111111-#252525");
                using (var draw = new DrawingWand())
                {
                    using (var fcolor = new PixelWand(ColorName.White))
                    {
                        draw.FillColor = fcolor;
                        draw.Font = MontserratLightFont;
                        draw.FontSize = 50;
                        draw.FontWeight = FontWeightType.LightStyle;
                        draw.TextAntialias = true;
                    }

                    var fontMetrics = wand.QueryFontMetrics(draw, text);
                    var textContainerY = Convert.ToInt32(height * .165);
                    wand.CurrentImage.AnnotateImage(draw, (width - fontMetrics.TextWidth) / 2, textContainerY, 0.0, text);

                    var iSlice = Convert.ToInt32(width * .1166666667);
                    int iTrans = Convert.ToInt32(height * 0.2);
                    int iHeight = Convert.ToInt32(height * 0.46296296296296296296296296296296);
                    var horizontalImagePadding = Convert.ToInt32(width * 0.0125);

                    foreach (var element in wandImages.ImageList)
                    {
                        int iWidth = (int)Math.Abs(iHeight * element.Width / element.Height);
                        element.Gravity = GravityType.CenterGravity;
                        element.BackgroundColor = new PixelWand("none", 1);
                        element.ResizeImage(iWidth, iHeight, FilterTypes.LanczosFilter);
                        int ix = (int)Math.Abs((iWidth - iSlice) / 2);
                        element.CropImage(iSlice, iHeight, ix, 0);

                        element.ExtentImage(iSlice, iHeight, 0 - horizontalImagePadding, 0);
                    }

                    wandImages.SetFirstIterator();
                    using (var wandList = wandImages.AppendImages())
                    {
                        wandList.CurrentImage.TrimImage(1);
                        using (var mwr = wandList.CloneMagickWand())
                        {
                            mwr.CurrentImage.ResizeImage(wandList.CurrentImage.Width, (wandList.CurrentImage.Height / 2), FilterTypes.LanczosFilter, 1);
                            mwr.CurrentImage.FlipImage();

                            mwr.CurrentImage.AlphaChannel = AlphaChannelType.DeactivateAlphaChannel;
                            mwr.CurrentImage.ColorizeImage(ColorName.Black, ColorName.Grey56);

                            using (var mwg = new MagickWand(wandList.CurrentImage.Width, iTrans))
                            {
                                mwg.OpenImage("gradient:black-none");
                                var verticalSpacing = Convert.ToInt32(height * 0.00555555555555555555555555555556);
                                mwr.CurrentImage.CompositeImage(mwg, CompositeOperator.DstInCompositeOp, 0, verticalSpacing);

                                wandList.AddImage(mwr);
                                int ex = (int)(wand.CurrentImage.Width - mwg.CurrentImage.Width) / 2;
                                wand.CurrentImage.CompositeImage(wandList.AppendImages(true), CompositeOperator.AtopCompositeOp, ex, Convert.ToInt32(height * 0.26851851851851851851851851851852));
                            }
                        }
                    }
                }

                return wand;
            }
        }

        private string MontserratLightFont
        {
            get { return PlayedIndicatorDrawer.ExtractFont("MontserratLight.otf", _appPaths); }
        }
    }
}