How to split an animated gif in .net?

问题

How do you split an animated gif into its component parts in .net?

Specifically I want to load them into Image(s) (System.Drawing.Image) in memory.

======================

Based on SLaks' answer i now have this

public static IEnumerable<Bitmap> GetImages(Stream stream)
{
    using (var gifImage = Image.FromStream(stream))
    {
        //gets the GUID
        var dimension = new FrameDimension(gifImage.FrameDimensionsList[0]);
        //total frames in the animation
        var frameCount = gifImage.GetFrameCount(dimension); 
        for (var index = 0; index < frameCount; index++)
        {
            //find the frame
            gifImage.SelectActiveFrame(dimension, index);
            //return a copy of it
            yield return (Bitmap) gifImage.Clone();
        }
    }
}

回答1:

Use the SelectActiveFrame method to select the active frame of an Image instance holding an animated GIF. For example:

image.SelectActiveFrame(FrameDimension.Time, frameIndex);

To get the number of frames, call GetFrameCount(FrameDimension.Time)

If you just want to play the animation, you can put it into a PictureBox or use the ImageAnimator class.

回答2:

// Parses individual Bitmap frames from a multi-frame Bitmap into an array of Bitmaps

private Bitmap[] ParseFrames(Bitmap Animation)
{
    // Get the number of animation frames to copy into a Bitmap array

    int Length = Animation.GetFrameCount(FrameDimension.Time);

    // Allocate a Bitmap array to hold individual frames from the animation

    Bitmap[] Frames = new Bitmap[Length];

    // Copy the animation Bitmap frames into the Bitmap array

    for (int Index = 0; Index < Length; Index++)
    {
        // Set the current frame within the animation to be copied into the Bitmap array element

        Animation.SelectActiveFrame(FrameDimension.Time, Index);

        // Create a new Bitmap element within the Bitmap array in which to copy the next frame

        Frames[Index] = new Bitmap(Animation.Size.Width, Animation.Size.Height);

        // Copy the current animation frame into the new Bitmap array element

        Graphics.FromImage(Frames[Index]).DrawImage(Animation, new Point(0, 0));
    }

    // Return the array of Bitmap frames

    return Frames;
}

回答3:

Semi-related, in WPF you have the BitmapDecoders which will provide you with all the frames of an image.

See BitmapDecoder.Create and BitmapDecoder.Frames.

回答4:

Image img = Image.FromFile(@"D:\images\zebra.gif");
//retrieving 1st frame
 img.SelectActiveFrame(new FrameDimension(img.FrameDimensionsList[0]), 1);
 pictureBox1.Image = new Bitmap(img);

来源：https://stackoverflow.com/questions/1712708/how-to-split-an-animated-gif-in-net