jellyfin/Emby.Drawing.Skia/StripCollageBuilder.cs
2019-01-13 20:16:43 +01:00

235 lines
9.7 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using MediaBrowser.Common.Configuration;
using MediaBrowser.Model.IO;
using SkiaSharp;
namespace Emby.Drawing.Skia
{
public class StripCollageBuilder
{
private readonly IApplicationPaths _appPaths;
private readonly IFileSystem _fileSystem;
public StripCollageBuilder(IApplicationPaths appPaths, IFileSystem fileSystem)
{
_appPaths = appPaths;
_fileSystem = fileSystem;
}
public static SKEncodedImageFormat GetEncodedFormat(string outputPath)
{
if (outputPath == null)
{
throw new ArgumentNullException(nameof(outputPath));
}
var ext = Path.GetExtension(outputPath).ToLower();
if (ext == ".jpg" || ext == ".jpeg")
return SKEncodedImageFormat.Jpeg;
if (ext == ".webp")
return SKEncodedImageFormat.Webp;
if (ext == ".gif")
return SKEncodedImageFormat.Gif;
if (ext == ".bmp")
return SKEncodedImageFormat.Bmp;
// default to png
return SKEncodedImageFormat.Png;
}
public void BuildPosterCollage(string[] paths, string outputPath, int width, int height)
{
// @todo
}
public void BuildSquareCollage(string[] paths, string outputPath, int width, int height)
{
using (var bitmap = BuildSquareCollageBitmap(paths, width, height))
{
using (var outputStream = new SKFileWStream(outputPath))
{
using (var pixmap = new SKPixmap(new SKImageInfo(width, height), bitmap.GetPixels()))
{
pixmap.Encode(outputStream, GetEncodedFormat(outputPath), 90);
}
}
}
}
public void BuildThumbCollage(string[] paths, string outputPath, int width, int height)
{
using (var bitmap = BuildThumbCollageBitmap(paths, width, height))
{
using (var outputStream = new SKFileWStream(outputPath))
{
using (var pixmap = new SKPixmap(new SKImageInfo(width, height), bitmap.GetPixels()))
{
pixmap.Encode(outputStream, GetEncodedFormat(outputPath), 90);
}
}
}
}
private SKBitmap BuildThumbCollageBitmap(string[] paths, int width, int height)
{
var bitmap = new SKBitmap(width, height);
using (var canvas = new SKCanvas(bitmap))
{
canvas.Clear(SKColors.Black);
// determine sizes for each image that will composited into the final image
var iSlice = Convert.ToInt32(width * 0.23475);
int iTrans = Convert.ToInt32(height * .25);
int iHeight = Convert.ToInt32(height * .70);
var horizontalImagePadding = Convert.ToInt32(width * 0.0125);
var verticalSpacing = Convert.ToInt32(height * 0.01111111111111111111111111111111);
int imageIndex = 0;
for (int i = 0; i < 4; i++)
{
using (var currentBitmap = GetNextValidImage(paths, imageIndex, out int newIndex))
{
imageIndex = newIndex;
if (currentBitmap == null)
{
continue;
}
// resize to the same aspect as the original
int iWidth = (int)Math.Abs(iHeight * currentBitmap.Width / currentBitmap.Height);
using (var resizeBitmap = new SKBitmap(iWidth, iHeight, currentBitmap.ColorType, currentBitmap.AlphaType))
{
currentBitmap.ScalePixels(resizeBitmap, SKFilterQuality.High);
// crop image
int ix = (int)Math.Abs((iWidth - iSlice) / 2);
using (var image = SKImage.FromBitmap(resizeBitmap))
using (var subset = image.Subset(SKRectI.Create(ix, 0, iSlice, iHeight)))
{
// draw image onto canvas
canvas.DrawImage(subset ?? image, (horizontalImagePadding * (i + 1)) + (iSlice * i), verticalSpacing);
if (subset == null)
{
continue;
}
// create reflection of image below the drawn image
using (var croppedBitmap = SKBitmap.FromImage(subset))
using (var reflectionBitmap = new SKBitmap(croppedBitmap.Width, croppedBitmap.Height / 2, croppedBitmap.ColorType, croppedBitmap.AlphaType))
{
// resize to half height
currentBitmap.ScalePixels(reflectionBitmap, SKFilterQuality.High);
using (var flippedBitmap = new SKBitmap(reflectionBitmap.Width, reflectionBitmap.Height, reflectionBitmap.ColorType, reflectionBitmap.AlphaType))
using (var flippedCanvas = new SKCanvas(flippedBitmap))
{
// flip image vertically
var matrix = SKMatrix.MakeScale(1, -1);
matrix.SetScaleTranslate(1, -1, 0, flippedBitmap.Height);
flippedCanvas.SetMatrix(matrix);
flippedCanvas.DrawBitmap(reflectionBitmap, 0, 0);
flippedCanvas.ResetMatrix();
// create gradient to make image appear as a reflection
var remainingHeight = height - (iHeight + (2 * verticalSpacing));
flippedCanvas.ClipRect(SKRect.Create(reflectionBitmap.Width, remainingHeight));
using (var gradient = new SKPaint())
{
gradient.IsAntialias = true;
gradient.BlendMode = SKBlendMode.SrcOver;
gradient.Shader = SKShader.CreateLinearGradient(new SKPoint(0, 0), new SKPoint(0, remainingHeight), new[] { new SKColor(0, 0, 0, 128), new SKColor(0, 0, 0, 208), new SKColor(0, 0, 0, 240), new SKColor(0, 0, 0, 255) }, null, SKShaderTileMode.Clamp);
flippedCanvas.DrawPaint(gradient);
}
// finally draw reflection onto canvas
canvas.DrawBitmap(flippedBitmap, (horizontalImagePadding * (i + 1)) + (iSlice * i), iHeight + (2 * verticalSpacing));
}
}
}
}
}
}
}
return bitmap;
}
private SKBitmap GetNextValidImage(string[] paths, int currentIndex, out int newIndex)
{
Dictionary<int, int> imagesTested = new Dictionary<int, int>();
SKBitmap bitmap = null;
while (imagesTested.Count < paths.Length)
{
if (currentIndex >= paths.Length)
{
currentIndex = 0;
}
bitmap = SkiaEncoder.Decode(paths[currentIndex], false, _fileSystem, null, out SKEncodedOrigin origin);
imagesTested[currentIndex] = 0;
currentIndex++;
if (bitmap != null)
{
break;
}
}
newIndex = currentIndex;
return bitmap;
}
private SKBitmap BuildSquareCollageBitmap(string[] paths, int width, int height)
{
var bitmap = new SKBitmap(width, height);
var imageIndex = 0;
var cellWidth = width / 2;
var cellHeight = height / 2;
using (var canvas = new SKCanvas(bitmap))
{
for (var x = 0; x < 2; x++)
{
for (var y = 0; y < 2; y++)
{
using (var currentBitmap = GetNextValidImage(paths, imageIndex, out int newIndex))
{
imageIndex = newIndex;
if (currentBitmap == null)
{
continue;
}
using (var resizedBitmap = new SKBitmap(cellWidth, cellHeight, currentBitmap.ColorType, currentBitmap.AlphaType))
{
// scale image
currentBitmap.ScalePixels(resizedBitmap, SKFilterQuality.High);
// draw this image into the strip at the next position
var xPos = x * cellWidth;
var yPos = y * cellHeight;
canvas.DrawBitmap(resizedBitmap, xPos, yPos);
}
}
}
}
}
return bitmap;
}
}
}