WPF Animated GIF Use Too Much Memory for Displaying Large GIF Image

问题

I want to display a GIF by using a library WPF Animated GIF. But when the property PictureSource is set, the process memory rises from 208MB to 1GB. Why?

XAML

<Image Name="content" MaxHeight="240" MaxWidth="340" 
       RenderOptions.BitmapScalingMode="LowQuality"
       Width="340" Height="240"
       MinWidth="340" MinHeight="240"
       gif:ImageBehavior.AutoStart="True"
       gif:ImageBehavior.AnimatedSource="{Binding Path=PictureSource}">
        <Image.Stretch>
            <MultiBinding Converter="{StaticResource ImageStretchConverter}">
                <Binding Path="PictureSource" />
                <Binding ElementName="content" Path="Source.Width" />
                <Binding ElementName="content" Path="Source.Height" />
            </MultiBinding>
        </Image.Stretch>
        <Image.BitmapEffect>
            <BlurBitmapEffect Radius="0" />
        </Image.BitmapEffect>
    <Image.CacheMode>
        <BitmapCache EnableClearType="True" 
                RenderAtScale="0.2" 
                SnapsToDevicePixels="True"/>
    </Image.CacheMode>
    <!--<Image.Source>
        <BitmapImage StreamSource="{Binding Path=PictureSource}" UriSource="{Binding Path=PictureSource}"
            DecodePixelWidth="340" DecodePixelHeight="240"/>
    </Image.Source>-->
</Image>

ImageStretchConverter

public object Convert(object[] values, Type targetType, object parameter, CultureInfo culture) {
    string path = values[0] as string;
    if (string.IsNullOrEmpty(path) || values[1] == DependencyProperty.UnsetValue || values[2] == DependencyProperty.UnsetValue) {
        return Stretch.None;
    }

    if (Path.GetExtension(path).ToLower() == ".gif") {
        double width = (double)values[1];
        double height = (double)values[2];
        if (width > Configuration.MaxThumbnailResolution || height > Configuration.MaxThumbnailResolution) {
            return Stretch.UniformToFill;
        }
    }

    return Stretch.None;
}

The size of the original GIF image is quite high. This may cause the problem. How can I set the DecodePixelWidth and DecodePixelHeight of the AnimatedSource?

回答1:

Have you read this article on the problem? https://www.thomaslevesque.com/2015/01/17/a-new-library-to-display-animated-gifs-in-xaml-apps/

The problem is most likely caused by a mistake the developer made when creating the library. You can read all about it in the article, but for a short explanation.

All the frames are pre-rendered in memory, for large gifs this is a big problem. Sadly enough there really isn't a easy fix for that when using the same library without re-programming it.

I'd recommend trying to use XamlAnimatedGif.

https://github.com/thomaslevesque/XamlAnimatedGif

(Which was made by the Same Developer)

来源：https://stackoverflow.com/questions/45768644/wpf-animated-gif-use-too-much-memory-for-displaying-large-gif-image

标签

wpf

xaml

animated-gif