public static MemoryBitmap Read(System.IO.Stream stream, IBitmapDecoder[] decoders, int?bytesToReadHint = null)
{
if (decoders.Length == 0)
{
decoders = GetDefaultDecoders().ToArray();
}
Guard.NotNull(nameof(stream), stream);
Guard.IsTrue(nameof(stream), stream.CanRead);
Guard.NotNull(nameof(decoders), decoders);
Guard.GreaterThan(nameof(decoders), decoders.Length, 0);
Guard.GreaterThan(nameof(bytesToReadHint), bytesToReadHint ?? 1, 0);
// it the stream position cannot be reset,
// and there's more than one decoder,
// load the source into a temporary memory buffer:
if (!stream.CanSeek && decoders.Length > 1)
{
using var mem = _ToMemoryStream(stream, bytesToReadHint);
return(Read(mem, decoders, (int)mem.Length));
}
System.Diagnostics.Debug.Assert(stream.CanSeek);
System.Diagnostics.Debug.Assert(stream.CanRead);
// remember the current stream position in case we need to reset it:
var startPos = stream.Position;
// loop over each decoder:
foreach (var decoder in decoders)
{
var context = new BitmapDecoderContext
{
Stream = stream,
BytesToRead = bytesToReadHint
};
// try to load the file with the current decoder:
if (decoder.TryRead(context, out MemoryBitmap bmp))
{
return(bmp);
}
#if DEBUG
stream.Position = 0;
stream.ReadByte();
#endif
// last decoder failed, reset the stream position:
stream.Position = startPos;
}
throw new ArgumentException("invalid format or incompatible decoder.", nameof(stream));
}
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext readContext, out MemoryBitmap bitmap)
{
try
{
bitmap = ReadRaw(readContext.Stream).First();
return(true);
}
catch (System.IO.IOException)
{
bitmap = default;
return(false);
}
}
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext context, out MemoryBitmap bitmap)
{
bitmap = default;
using (var mat = OpenCvSharp.Mat.FromStream(context.Stream, OpenCvSharp.ImreadModes.AnyColor))
{
if (mat.Cols == 0)
{
return(false);
}
bitmap = mat.AsSpanBitmap().ToMemoryBitmap();
}
return(true);
}
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext context, out MemoryBitmap bitmap)
{
try
{
var frame = System.Windows.Media.Imaging.BitmapFrame.Create(context.Stream, System.Windows.Media.Imaging.BitmapCreateOptions.PreservePixelFormat, System.Windows.Media.Imaging.BitmapCacheOption.None);
bitmap = _Implementation.ToMemoryBitmap(frame);
return(true);
}
catch (System.NotSupportedException)
{
bitmap = default;
return(false);
}
}
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext context, out MemoryBitmap bitmap)
{
try
{
using (var img = System.Drawing.Image.FromStream(context.Stream))
{
bitmap = _Implementation.CloneAsMemoryBitmap(img);
}
return(true);
}
catch (System.ArgumentException)
{
bitmap = default;
return(false);
}
}
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext context, out MemoryBitmap bitmap)
{
try
{
using (var img = SixLabors.ImageSharp.Image.Load(context.Stream))
{
bitmap = img.ToMemoryBitmap();
}
return(true);
}
catch (SixLabors.ImageSharp.UnknownImageFormatException)
{
bitmap = default;
return(false);
}
}
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext context, out MemoryBitmap bitmap)
{
try
{
bitmap = default;
var bmp = Android.Graphics.BitmapFactory.DecodeStream(context.Stream);
bmp.CopyTo(ref bitmap);
return(true);
}
catch (System.ArgumentException)
{
bitmap = default;
return(false);
}
}
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext context, out MemoryBitmap bitmap)
{
bitmap = default;
try
{
var img = STBREAD.ImageResult.FromStream(context.Stream, STBREAD.ColorComponents.RedGreenBlueAlpha);
bitmap = _Implementation.AsMemoryBitmap(img);
return(true);
}
catch (Exception ex)
{
if (ex.Message == "unknown image type")
{
return(false);
}
else
{
throw ex;
}
}
}
// TODO: we should try to operate directly with SkiaSharp.SKCodec
/// <inheritdoc/>
public bool TryRead(BitmapDecoderContext context, out MemoryBitmap bitmap)
{
bitmap = default;
if (context.BytesToRead.HasValue)
{
using (var data = SkiaSharp.SKData.Create(context.Stream, context.BytesToRead.Value))
{
using (var skc = SkiaSharp.SKCodec.Create(data))
{
if (skc == null)
{
bitmap = default; return(false);
}
var binfo = _Implementation.GetBitmapInfo(skc.Info);
bitmap = new MemoryBitmap(skc.Pixels, binfo);
return(true);
}
}
}
using (var skc = SkiaSharp.SKCodec.Create(context.Stream))
{
if (skc == null)
{
bitmap = default; return(false);
}
var binfo = _Implementation.GetBitmapInfo(skc.Info);
bitmap = new MemoryBitmap(skc.Pixels, binfo);
return(true);
}
return(false);
}