private async Task SingleImageTypeTest(
IList <string> resourceNames,
ImageFormat expectedImageType)
{
foreach (string name in resourceNames)
{
Stream resourceStream = await GetResourceStream(name);
try
{
Assert.AreEqual(
expectedImageType,
ImageFormatChecker.GetImageFormat(resourceStream),
"failed with resource: " + name);
}
finally
{
resourceStream.Dispose();
}
}
}
/// <summary>
/// Decodes image.
/// </summary>
/// <param name="encodedImage">
/// Input image (encoded bytes plus meta data).
/// </param>
/// <param name="length">
/// If image type supports decoding incomplete image then
/// determines where the image data should be cut for decoding.
/// </param>
/// <param name="qualityInfo">
/// Quality information for the image.
/// </param>
/// <param name="options">
/// Options that cange decode behavior.
/// </param>
public Task <CloseableImage> DecodeImageAsync(
EncodedImage encodedImage,
int length,
IQualityInfo qualityInfo,
ImageDecodeOptions options)
{
ImageFormat imageFormat = encodedImage.Format;
if (imageFormat == ImageFormat.UNINITIALIZED || imageFormat == ImageFormat.UNKNOWN)
{
imageFormat = ImageFormatChecker.GetImageFormat_WrapIOException(
encodedImage.GetInputStream());
encodedImage.Format = imageFormat;
}
switch (imageFormat)
{
case ImageFormat.UNKNOWN:
throw new ArgumentException("unknown image format");
case ImageFormat.JPEG:
return(DecodeJpegAsync(encodedImage, length, qualityInfo)
.ContinueWith(
task => ((CloseableImage)task.Result),
TaskContinuationOptions.ExecuteSynchronously));
case ImageFormat.GIF:
return(DecodeGifAsync(encodedImage, options));
case ImageFormat.WEBP_ANIMATED:
return(DecodeAnimatedWebpAsync(encodedImage, options));
default:
return(DecodeStaticImageAsync(encodedImage)
.ContinueWith(
task => ((CloseableImage)task.Result),
TaskContinuationOptions.ExecuteSynchronously));
}
}
/// <summary>
/// Sets the encoded image meta data.
/// </summary>
public async Task ParseMetaDataAsync()
{
ImageFormat format = ImageFormatChecker.GetImageFormat_WrapIOException(
GetInputStream());
Format = format;
// Dimensions decoding is not yet supported for WebP since
// BitmapUtil.DecodeDimensions has a bug where it will return 100x100 for
// some WebPs even though those are not its actual dimensions.
if (!ImageFormatHelper.IsWebpFormat(Format))
{
Tuple <int, int> dimensions = await BitmapUtil
.DecodeDimensionsAsync(GetInputStream())
.ConfigureAwait(false);
if (dimensions != default(Tuple <int, int>))
{
Width = dimensions.Item1;
Height = dimensions.Item2;
// Load the rotation angle only if we have the dimensions
if (Format == ImageFormat.JPEG)
{
if (RotationAngle == UNKNOWN_ROTATION_ANGLE)
{
RotationAngle = JfifUtil.GetAutoRotateAngleFromOrientation(
JfifUtil.GetOrientation(GetInputStream()));
}
}
else
{
RotationAngle = 0;
}
}
}
}
