public VideoFile(
VideoFile other,
int imageCount = 0)
{
if (other is null)
{
throw new ArgumentNullException(nameof(other));
}
ImageCount = imageCount;
// We have to do a bit more work here since we can't use
// the other ctors because we don't want to eagerly load
// the images when we can copy them from the other file.
filePath = other.filePath;
fileSize = other.fileSize;
duration = other.duration;
codecInfo = other.codecInfo;
if (ImageCount == 0)
{
return;
}
if (other.ImageCount == ImageCount)
{
imageStreams = other.imageStreams
.Select(image =>
{
var ms = new MemoryStream();
image.Position = 0;
image.CopyTo(ms);
return(ms);
})
.ToList();
return;
}
using (var mpv = new MpvWrapper(FilePath, imageCount, Duration))
{
imageStreams = mpv.GetImages(0, imageCount).ToList();
}
}
public VideoFile(
string filePath,
int imageCount = 0)
{
if (string.IsNullOrWhiteSpace(filePath))
{
throw new ArgumentException($"'{nameof(filePath)}' cannot be" +
$" null or whitespace", nameof(filePath));
}
this.filePath = filePath;
ImageCount = imageCount;
if (ImageCount == 0)
{
return;
}
using (var mpv = new MpvWrapper(FilePath, ImageCount, Duration))
{
imageStreams = mpv.GetImages(0, ImageCount).ToList();
}
}
private (MemoryStream ImageStream, int LoadLevel) LoadImage(
VideoFile videoFile,
int index,
IImageComparisonSettings settings)
{
if (index >= settings.MaxImageCompares || index < 0)
{
throw new ArgumentOutOfRangeException(nameof(index),
"Index out of range.");
}
if (videoFile.ImageCount != 0 &&
videoFile.ImageCount != settings.MaxImageCompares)
{
videoFile.DisposeImages();
}
videoFile.ImageCount = settings.MaxImageCompares;
if (index < videoFile.ImageStreams.Count())
{
return(videoFile.ImageStreams[index], 0);
}
using (var mpv = new MpvWrapper(
videoFile.FilePath,
settings.MaxImageCompares,
videoFile.Duration))
{
// First loading step, only the minimum (when index == 0)
var imagesToLoad = settings.MaxDifferentImages + 1;
var loadLevel = 1;
// Second loading step
if (index == settings.MaxDifferentImages + 1)
{
imagesToLoad = settings.MaxImageCompares
- index
- settings.MaxDifferentImages;
loadLevel = 2;
}
// Third loading step
else if (index
== settings.MaxImageCompares - settings.MaxDifferentImages)
{
imagesToLoad = settings.MaxDifferentImages;
loadLevel = 3;
}
// To make sure we never load more than we initially wanted.
imagesToLoad = Math.Min(
imagesToLoad,
settings.MaxImageCompares - index);
foreach (var image in mpv.GetImages(index, imagesToLoad))
{
videoFile.ImageStreams.Add(image);
}
if (index >= videoFile.ImageStreams.Count())
{
return(null, loadLevel);
}
return(videoFile.ImageStreams[index], loadLevel);
}
}