Extracting Animated Webp

[Julian Lugod]

Hi, noob question. How do I extract all sequential frames  from an Animated Webp to PNG. 

[Vincent Rabaud]

Hi Julian,

what you are looking for is the webpmux utility in the examples folder: https://developers.google.com/speed/webp/docs/webpmux

The following example is given to get the 2nd frame from an animated WebP file:

webpmux -get frame 2 anim_container.webp -o frame_2.webp

On Fri, Aug 18, 2017 at 4:05 PM, Julian Lugod <anamar...@gmail.com> wrote:

Hi, noob question. How do I extract all sequential frames  from an Animated Webp to PNG. 

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[Pascal Massimino]

Hi,

On Mon, Aug 21, 2017 at 6:12 PM, Vincent Rabaud <vincent...@gmail.com> wrote:

Hi Julian,

what you are looking for is the webpmux utility in the examples folder: https://developers.google.com/speed/webp/docs/webpmux

The following example is given to get the 2nd frame from an animated WebP file:

webpmux -get frame 2 anim_container.webp -o frame_2.webp

Actually, this will save the raw .webp data, which may not be what you expect. In particular, it will

not reconstruct the frames (taking the DISPOSE method into account).

It's actually relatively easy to reconstruct and extract the frames with the API. This is what the

small tool 'anim_diff' is doing, for instance. But using anim_diff to dump frames, even if possible,

feels a bit awkward.

So, out of simplicity, i just went ahead and quickly coded a small tool to call the API and dump

the reconstructed frames from an animation. It's called 'anim_dump', and the patch is here:

   https://chromium-review.googlesource.com/638210

You just need to call './examples/anim_dump my_anim.webp' to get the frames 'dump_xxxx.png'.

hope it helps,

skal/

[Phil Warren]

Hello,

Was curious how to apply the patch?  New to this, thank you in advance!

On Monday, August 28, 2017 at 7:10:04 AM UTC-7 pascal.m...@gmail.com wrote:

Hi,

On Mon, Aug 21, 2017 at 6:12 PM, Vincent Rabaud <vincent...@gmail.com> wrote:

Hi Julian,

what you are looking for is the webpmux utility in the examples folder: https://developers.google.com/speed/webp/docs/webpmux

The following example is given to get the 2nd frame from an animated WebP file:

webpmux -get frame 2 anim_container.webp -o frame_2.webp

Actually, this will save the raw .webp data, which may not be what you expect. In particular, it will

not reconstruct the frames (taking the DISPOSE method into account).

It's actually relatively easy to reconstruct and extract the frames with the API. This is what the

small tool 'anim_diff' is doing, for instance. But using anim_diff to dump frames, even if possible,

feels a bit awkward.

So, out of simplicity, i just went ahead and quickly coded a small tool to call the API and dump

the reconstructed frames from an animation. It's called 'anim_dump', and the patch is here:

   https://chromium-review.googlesource.com/638210

You just need to call './examples/anim_dump my_anim.webp' to get the frames 'dump_xxxx.png'.

hope it helps,

skal/

On Fri, Aug 18, 2017 at 4:05 PM, Julian Lugod <anamar...@gmail.com> wrote:

Hi, noob question. How do I extract all sequential frames  from an Animated Webp to PNG. 

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[James Zern]

Hi,

On Tue, Nov 8, 2022 at 1:25 AM Phil Warren <jagge...@gmail.com> wrote:

Hello,

Was curious how to apply the patch?  New to this, thank you in advance!

That patch landed quite some time ago [1]; anim_dump has been available since v0.6.1.

Gerrit offers various ways to download the diff, though. Click on the overflow menu (3 vertical '.'s) in the upper right corner (or hit the 'd' key) to see some ways to download using git or via an archive.

[1] https://chromium.googlesource.com/webm/libwebp/+/f66f94ef369b21e1333c1e5119d4210082604018

 

To view this discussion on the web visit https://groups.google.com/a/webmproject.org/d/msgid/webp-discuss/d05c98ec-1cb6-4543-8c2c-c1c274097294n%40webmproject.org.

[Eduardo Spuqui]

I do manage to extract all frames from a WebP animation, either by using anim_dump or by using webpmux to extract the webp frames and then using dwebp to convert each frame back to PNG format.

My issue is that when I recompile the PNG frames into a WebP animation, the file size is a little smaller than the original WebP animation, indicating there was data loss in this process.

Is there a way to disassemble a WebP animation into PNG frames without any data loss so that when recompiling the WebP animation from the PNG frames it would be exactly the same size as the original WebP animation?

On Monday, August 28, 2017 at 11:10:04 AM UTC-3 Pascal Massimino wrote:

Hi,

On Mon, Aug 21, 2017 at 6:12 PM, Vincent Rabaud <vincent...@gmail.com> wrote:

Hi Julian,

what you are looking for is the webpmux utility in the examples folder: https://developers.google.com/speed/webp/docs/webpmux

The following example is given to get the 2nd frame from an animated WebP file:

webpmux -get frame 2 anim_container.webp -o frame_2.webp

Actually, this will save the raw .webp data, which may not be what you expect. In particular, it will

not reconstruct the frames (taking the DISPOSE method into account).

It's actually relatively easy to reconstruct and extract the frames with the API. This is what the

small tool 'anim_diff' is doing, for instance. But using anim_diff to dump frames, even if possible,

feels a bit awkward.

So, out of simplicity, i just went ahead and quickly coded a small tool to call the API and dump

the reconstructed frames from an animation. It's called 'anim_dump', and the patch is here:

   https://chromium-review.googlesource.com/638210

You just need to call './examples/anim_dump my_anim.webp' to get the frames 'dump_xxxx.png'.

hope it helps,

skal/

On Fri, Aug 18, 2017 at 4:05 PM, Julian Lugod <anamar...@gmail.com> wrote:

Hi, noob question. How do I extract all sequential frames  from an Animated Webp to PNG. 

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[Vincent Rabaud]

The frames are dumped, not recompressed.
The size reduction you are seeing is probably because:
- you recompresse with different lossless settings (E.g. with more effort)
- your animation was compressed with a certain version of WebP and when it is re-compressed, you use a newer version that has better lossless compression

Can you please open up a bug as indicated at https://developers.google.com/speed/webp/community, with your animation and the command line you use? Thx.

To view this discussion on the web visit https://groups.google.com/a/webmproject.org/d/msgid/webp-discuss/cec8e12a-95d4-4348-8909-e6ea0d4d856cn%40webmproject.org.