jellyfin-server/Jellyfin.Drawing.Skia/StripCollageBuilder.cs
Bond_009 aa30227545 Improve main code flow
Improved the way how some parts of the code depend on eachother
Fixed some style issues
2019-06-09 23:51:52 +02:00

186 lines
6.6 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using SkiaSharp;
namespace Jellyfin.Drawing.Skia
{
public class StripCollageBuilder
{
private readonly SkiaEncoder _skiaEncoder;
public StripCollageBuilder(SkiaEncoder skiaEncoder)
{
_skiaEncoder = skiaEncoder;
}
public static SKEncodedImageFormat GetEncodedFormat(string outputPath)
{
if (outputPath == null)
{
throw new ArgumentNullException(nameof(outputPath));
}
var ext = Path.GetExtension(outputPath);
if (string.Equals(ext, ".jpg", StringComparison.OrdinalIgnoreCase)
|| string.Equals(ext, ".jpeg", StringComparison.OrdinalIgnoreCase))
{
return SKEncodedImageFormat.Jpeg;
}
if (string.Equals(ext, ".webp", StringComparison.OrdinalIgnoreCase))
{
return SKEncodedImageFormat.Webp;
}
if (string.Equals(ext, ".gif", StringComparison.OrdinalIgnoreCase))
{
return SKEncodedImageFormat.Gif;
}
if (string.Equals(ext, ".bmp", StringComparison.OrdinalIgnoreCase))
{
return SKEncodedImageFormat.Bmp;
}
// default to png
return SKEncodedImageFormat.Png;
}
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);
// number of images used in the thumbnail
var iCount = 3;
// determine sizes for each image that will composited into the final image
var iSlice = Convert.ToInt32(width / iCount);
int iHeight = Convert.ToInt32(height * 1.00);
int imageIndex = 0;
for (int i = 0; i < iCount; 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, iSlice * i, 0);
}
}
}
}
}
return bitmap;
}
private SKBitmap GetNextValidImage(string[] paths, int currentIndex, out int newIndex)
{
var 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, null, out var 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;
}
}
}