More problems extracting frames from GIFs

Question

Following my previous question (Gifs opened with python have broken frames) I now have code that works sometimes.

For example, this code

from PIL import Image

img = Image.open('pigs.gif')

counter = 0
collection = []
current = img.convert('RGBA')
while True:
    try:
        current.save('original%d.png' % counter, 'PNG')
        img.seek(img.tell()+1)
        current = Image.alpha_composite(current, img.convert('RGBA'))
        counter += 1
    except EOFError:
        break

…works on most GIFs perfectly, but on others it produces weird results. For example, when applied to this 2-frame GIF:

GIF

It produces these two frames:

Frame 1 Frame 2

The first one is ok, the second one not so much.

What now?

Try viewing the second frame without composting it with the first and see if it's what it ought be as far as what pixels have changed and have not. — martineau, Feb 25 '14 at 18:20

score 1 · Answer 1 · answered Feb 24 '14 at 19:22

1

Sounds like you want to do this:

while True:
    try:
        current.save('original%d.gif' % counter)
        img.seek(img.tell()+1)
        current = img.convert('RGBA')
        counter += 1
    except EOFError:
        break

answered Feb 24 '14 at 19:22

Clarus

2,259
16
27

You didn't really read the previous question, did you? My previous question was precisely that THAT code doesn't work. – Feb 24 '14 at 19:29
Great. So then what is your question? What about either this approach or the approach that another SO'er provided is wrong? – Clarus Feb 24 '14 at 20:03
In my question, I say what the question is: that code when applied to some gifs still produces a wrong result. – Feb 24 '14 at 20:11
What is wrong about the result. The result you showed looks like compositing an image on top of another image. The solution I have should (presumably) be the image without compositing. – Clarus Feb 24 '14 at 23:16
1

If you read my previous question, you'll see that the composition is necessary, because gif only saves changes from frame to frame. So what you have is not a "solution". Read the linked question please. – Feb 24 '14 at 23:32

score 1 · Answer 2 · answered Jul 10 '18 at 11:18

try Wand (Wand is a ctypes-based simple ImageMagick binding for Python.)

from wand.image import Image

def extract_frames(gif_file):
    with Image(filename=gif_file) as gif:
        for i, single_img in enumerate(gif.sequence):
            with Image(image=single_img) as frame:
                frame.format = 'PNG'
                frame.save(filename='frame-%d.png' % i)

extract_frames('test.gif')

frame-0.png

frame-1.png

More problems extracting frames from GIFs

2 Answers2

Linked