python wand中的帧没有消失

Question

根据here 的提示，我尝试创建一个包含 2 个不同图像的 gif，如下所示。它有效，但一帧并没有消失以显示另一帧。为什么会发生这种情况以及如何纠正？

from wand.image import Image as Image2

with Image2() as wand:
    # Add new frames into sequance
    with Image2(blob=d2) as one:
        wand.sequence.append(one)
    with Image2(blob=d3) as two:
        wand.sequence.append(two)

    # Create progressive delay for each frame
    for cursor in range(2):
        with wand.sequence[cursor] as frame:
            frame.delay = 100
    # Set layer type
    wand.type = 'optimize'
    wand.save(filename='animated.gif')

display(Image('animated.gif'))

当前输出：

Answer 1

更新答案

...我使用那个时出错了...

看起来硬编码的验证值不允许利用这种技术。这是一个错误，我将在上游提交一个补丁。

@ -2548,7 +2548,7 @@ class BaseImage(Resource):
         .. versionadded:: 0.4.3

         """
-        if method not in ['merge', 'flatten', 'mosaic']:
+        if method not in IMAGE_LAYER_METHOD:
             raise TypeError('method must be one of: merge, flatten, mosaic')

目前，wand 没有实现 C-API 方法 MagickSetImageDispose 或 MagickExtentImage，我相信这是您需要的。虽然实现这些方法相当容易，但您可能会被困在逐帧重建每个图像。

from wand.image import Image as Image2
from wand.color import Color
from wand.compat import nested

with nested(Image2(),
            Image2(filename='d2.gif'),
            Image2(filename='d3.gif')) as (wand, one, two):
    width = max(one.width, two.width)
    height = max(one.height, two.height)
    # Rebuild images with full extent of frame
    with Image2(width=width, height=height, background=Color('WHITE')) as f1:
        f1.composite(one, 0, 0)
        wand.sequence.append(f1)
    with Image2(width=width, height=height, background=Color('WHITE')) as f2:
        f2.composite(two, 0, 0)
        wand.sequence.append(f2)
    # Create progressive delay for each frame
    for cursor in range(2):
        with wand.sequence[cursor] as frame:
            frame.delay = 100
    wand.type = 'optimize'
    wand.save(filename='animated.gif')

原始答案请勿使用！

---

你想调用wand.image.Image.merge_layers方法，而不是wand.image.Image.type属性。

试试下面...

with Image2() as wand:
    # Add new frames into sequance
    with Image2(blob=d2) as one:
        wand.sequence.append(one)
    with Image2(blob=d3) as two:
        wand.sequence.append(two)

    # Create progressive delay for each frame
    for cursor in range(2):
        with wand.sequence[cursor] as frame:
            frame.delay = 100
    # Set layer type
    wand.merge_layers('optimize')  # or 'optimizeimage', or 'composite'
    wand.save(filename='animated.gif')