XAVC S format

fredo · July 1, 2020, 2:40pm

Hi,
I want to buy a Sony AX33, but before that I would like to know if Shotcut supports Sony video format [XAVC S 4K], [XAVC S HD] and [AVCHD].
There’s some information on this forum but it’s not very clear, and I would like to be sure before buying camera.
Thanks so lot.

Elusien · July 1, 2020, 3:02pm

Why not download some sample videos e.g. from the site below, and try them out in Shotcut?

fredo · July 1, 2020, 3:39pm

Thanks Elusien,
I’ve made it and it works. But a question : are these realy the original files on this site ? I’m only asking because for example for the video XAVC S HD you can download the file in maximal 1280x720… normaly this format is native 1920x1080 (and the file you download is a MP4 file, is it normal?).
What do you think ?
Thanks (as you can see, I’m starting on video!)

Elusien · July 1, 2020, 8:41pm

Good question. I’m not really sure. I’ll see if I can find out.

fredo · July 1, 2020, 9:08pm

ok thanks, it would be nice

Elusien · July 2, 2020, 8:11am

I’m pretty sure they are not the original files. They are ones that are probably processed by Vimeo.

EDIT - To download the original you have to be logged into your own Vimeo account. I logged into my account, but it still wouldn’t offer the “ORIGAL” download format - I suspect the owner has to enable this.

I looked elsewhere on the web for sample footage and thought I’d hit paydirt when I got to:

But no matter which link I click on it fails to find the page. You could try contacting the company (Z0Systems) to see if they can provide you with a sample.

fredo · July 2, 2020, 8:31am

Thanks for your help. Not easy to have this information on the compatibility XAVC/Shotcut…

Austin · July 2, 2020, 4:14pm

I don’t have an actual XAVC file to test, but the odds of Shotcut working with it are really good. If FFmpeg supports it, then Shotcut generally supports it (since Shotcut is built on top of FFmpeg). An FFmpeg forum post from 2013 suggests that XAVC 4K was already supported by FFmpeg all the way back then:

https://lists.ffmpeg.org/pipermail/ffmpeg-user/2013-June/015751.html

fredo · July 2, 2020, 5:18pm

Thanks Austin.
I watched the General Documentation of FFmpeg, and for the video codec “H.264 / AVC / MPEG-4 AVC / MPEG-4 part 10” (I think it’s the codec used by XAVC S), it says for encoding : " that support is provided through an external library".
I dowloaded the x264 library (for H.264 encoding), but I don’t know what to do next…
What do you think ?

Austin · July 2, 2020, 6:27pm

x264 is the external library. It’s already baked into FFmpeg as libx264. It’s external in the sense that FFmpeg developers did not write the code. The x264 team did. And then their work was included in FFmpeg as a bundled library.

There shouldn’t be anything extra for you to do. It should immediately work in Shotcut and through FFmpeg command line.

In theory, anyway.

fredo · July 2, 2020, 7:37pm

Ok, so I deduce that Shotcut should normally supports the XAVC format.
Thanks for your help.

fredo · July 3, 2020, 5:38am

Indeed in the Shotcut files, I see there is a file named “libx264-155.dll”, so it should be work for the video codec.

However I don’t know for the audio codec witch is AAC. The General doc of FFmpeg says for this audio codec : “encoding supported through internal encoder and external library libfdk-aac” ; and I don’t see any file in Shotcut that look like this library libfdk-aac…

Austin · July 3, 2020, 1:10pm

AAC is definitely supported in Shotcut. It is the default export format.

FFmpeg has two AAC encoders. One is native, the other is FDK. Shotcut does not include the FDK version for licensing reasons. So the native version is used, which means you won’t find an “aac.dll” file anywhere because native AAC isn’t in an external library.