convertCAMV.py: Convert your videos to/from .ca_vp8.

[jsirett]

Hi, everyone.. new to the TW modding community, but I'm coming in hot with something I've been assured is much requested.

I have reverse-engineered the .ca_vp8 movie file format used by ATW and later TW games, and made a small converter tool to decode and create .ca_vp8 videos.

The .ca_vp8 or ('CAMV') movie file appears to be a modified version of VP8 IVF (https://wiki.multimedia.cx/index.php/IVF). You can make an IVF file with FFmpeg using the '-c:v libvpx' and '-f ivf' options, or by using the reference 'vpxenc.exe' encoder from the WebM project (https://www.webmproject.org/). This small script will then convert your .ivf file to a .ca_vp8 file. Such files have been tested in ATW, but might work for TWH/TWH2/ToB/TW3K as well.

Note that .ca_vp8 files only encode video; the accompanying audio is handled seperately by the game, likely through Wwise.

The script can be downloaded here, as well as a few tenuous notes on the structure of the CAMV file format:
https://gitlab.com/johnsirett/ca_vp8-reverse.

Encoding video:

Videos must be 30fps, or converted to 30fps.

ffmpeg -i 'example.mkv' -c:v libvpx -crf 4 -b:v 10M -r 30 'front_end_background.ivf'
python convertCAMV.py 'front_end_background.ivf' 'front_end_background.ca_vp8'

Decoding video:

python convertCAMV.py 'intro.ca_vp8' 'intro.ivf'
ffmpeg -i 'intro.ivf' -c:v libx264 -preset slow -crf 22 'intro.mkv'

A technical description of the .ca_vp8 format is incoming...

[Benjin]

Excellent work man, thanks again for this!

[Frodo45127]

Good work man, really good work but... one question: There is no problem with me integrating this into RPFM isn't? Other than the license thing I mean (RPFM uses MIT license), but that can be easily solved. Of course, credits should be given, as always someone helps with something in RPFM.

[Jf120]

Hi Jsirett.

You are a genius!! It is working in WH2 as well. But, It doesn't work in TW3k.. I guess because 3k ca_vp8 file is over 3 mega bytes.

This is error message.

Traceback (most recent call last):
File "C:\ffmpeg\bin\convertCAMV.py", line 165, in <module>
camv_to_ivf(args.inFile, args.outFile)
File "C:\ffmpeg\bin\convertCAMV.py", line 59, in camv_to_ivf
frameData = inFile.read(frameEntry.frameSize)
OverflowError: cannot fit 'int' into an index-sized integer

Could you work it out?

Thanks in advance.

I respect you!

Stay safe.

[Jf120]

Hi jsirett.

I have managed it anyhow. It doesn't need to convert ca_vp8 to mkv. However, TW3K using transparent background video files.
And ffmpeg doesn't recognize alpha mov file or alpha avi.

I think webp needs to be convert to ivf file. Is it possible to convert webp to ivf?

Thank you in advance.

Stay safe.

[shawmuscle]

Hello, this is great! Amazing that you got it to work, unfortunately the link is no longer working https://gitlab.com/johnsirett/ca_vp8-reverse* shows page not found and I appear to be stuck using your guide, I have converted my file to .ivf and the scripts provided work up until I get to
[NULL @ 000002916e86a1c0] Unable to find a suitable output format for 'pythonconvertCAMV.py'pythonconvertCAMV.py: Invalid argument
so I assume it has something it has something to do with the missing files?

[Barbarous Barbarian]

Great stuff, exactly what I was looking for!!!

I am using it to clean and upscale WHII movies to 4k with https://www.topazlabs.com/video-enhance-ai

[Biggus Splenus]

TL;DR: works fine, here's a link to the new python script and stuff
https://gitlab.com/johnsirett-public/ca_vp8-reverse
Now does anyone know how audio works? Wth is wwise?

Has anyone got this file sitting around in their downloads? Would be great to get a hold of it, currently can't find another way around this.

edit: found it, but it appears to be broken for me. still trying though

edit2: noticed rpfm picked up that the exported videos have a framerate of 30.000002 rather than vanilla's 30.0003. I wasn't sure if it was worth trying, but I reprocessed the video files specifically at 30.0003 fps, which rpfm did verify for me. Still results in a crash when the game attempt to play the video...

Before I hit save of this edit, I realised I'm a moron and didn't add a db entry for the video. Works perfectly fine. Fun times.