private static unsafe bool DrawVideo(Stream videoStream, ThumbnailsRenderContext ctx)
{
using var formatContext = new FormatContext(videoStream);
var stream = formatContext.FindBestVideoStream();
if (stream == null)
{
return(false);
}
using var videoStreamDecoder = stream.CreateStreamDecoder();
try
{
if (videoStreamDecoder.Duration <= 0)
{
videoStreamDecoder.SeekFrame(10 * 1000000);
}
if (videoStreamDecoder.Duration > 3)
{
videoStreamDecoder.SeekFrame(videoStreamDecoder.Duration / 3);
}
}
catch (FFmpegException err)
{
Console.WriteLine("Seek failed: " + err);
}
var destinationSize = ThumbnailUtils.ContainSize(
new SKSize(videoStreamDecoder.FrameWidth, videoStreamDecoder.FrameHeight),
new SKSize(ThumbnailUtils.DefaultMaxWidth * ctx.Density, ThumbnailUtils.DefaultMaxHeight * ctx.Density)).ToSizeI();
var sourcePixelFormat = videoStreamDecoder.PixelFormat;
if (!videoStreamDecoder.MoveNext())
{
throw new InvalidDataException("Can't decode the video.");
}
using var vfc =
new VideoFrameConverter(
videoStreamDecoder.FrameWidth,
videoStreamDecoder.FrameHeight,
sourcePixelFormat,
destinationSize.Width,
destinationSize.Height);
var convertedFrame = vfc.Convert(videoStreamDecoder.Current.Value);
using var colorspace = SKColorSpace.CreateSrgb();
var sourceImageInfo = new SKImageInfo(
convertedFrame.width,
convertedFrame.height,
SKColorType.Rgba8888,
SKAlphaType.Unpremul,
colorspace);
using var image =
SKImage.FromPixels(sourceImageInfo, (IntPtr)convertedFrame.data[0], sourceImageInfo.RowBytes);
_cachedDecorationImage ??= SKImage.FromEncodedData(ReadDecorationImage());
ThumbnailUtils.DrawShadowView(
ctx,
new SkImageView(image),
_cachedDecorationImage,
new SKColor(0, 0, 0),
minSize: new SKSize(24, 24));
return(true);
}