New user experience (in steps)

Questions and answers on how to get the most out of FFAStrans
admin
Site Admin
Posts: 1303
Joined: Sat Feb 08, 2014 10:39 pm

Re: New user experience (in steps)

Post by admin » Fri Jun 16, 2017 6:39 pm

Maybe you can share a sample with me so that I can investigate?

-steinar

taner
Posts: 82
Joined: Sun Jun 19, 2016 6:36 pm

Re: New user experience (in steps)

Post by taner » Fri Jun 16, 2017 7:44 pm

Concerning MOV-DNXHD as far as I can see MediaComposer expects having just 1 audiostream (2x1, 4x1, 8x1 etc...)
If the MOV-file contains more than 1 audiostream it will not be imported.

It doesn't matter if you create your files with FFASTRANS and DNXHD-processor or use the command console or a different ffmpeg-version.

Concerning MXF-DNXHD it can has more than 1 audiostream.
Import is not possible but AMA-link and transcode instead.

I've transcoded a dozen MOV-DNXHD-testfiles with FFASTRANS in different resolutions and imported them successfully into different MediaComposer-projects.

Also I was able to ama-link your testfile.
Do you get an error-message in MediaComposer when ama-linking?
If not could you please go to "Tools - Console" in MediaComposer and look for the last entry after linking?

seePyou
Posts: 33
Joined: Tue Feb 07, 2017 2:54 pm

Re: New user experience (in steps)

Post by seePyou » Mon Apr 23, 2018 8:13 pm

I'm back ,after a long time, to continue the trek of making this work! Now I have a different issue; the size detection is wrong. I have an exported DNxHD 220 in a .mov container that is 1080p 60FPS, and it is transcoded by detection (%video_width% and so forth) to 1440x1080.
Shall I send you the movie file?
I'm attempting to force 1080p resolution to see if this helps, as the resulting file was not crisp.

seePyou
Posts: 33
Joined: Tue Feb 07, 2017 2:54 pm

Re: New user experience (in steps)

Post by seePyou » Mon Apr 23, 2018 11:10 pm

Yeah, some minor improvements, but I cannot get it to be stereo sound at all; it always transcodes to right audio channel. I have placed it in 1x2, 2x1, and same as source, but it's always making it right channel (maybe mixdown, don't know, but all I can hear is right channel audio).

Also, the quality isn't really stellar, and I've taken it to h.264 transcoding from 8000 to 10.000 and 12.000 bit rate and it is still not "great".

The comparison is based on source (1080p60 h.264 mp4) which is then AMA linked in Media Composer and then transcoded to DNxHD220 to work. Then export same as source in a .mov container and use FFAStrans to make it into an h.264 mp4 1080p60 again for upload.

As always, if you need any sample files or more information, let me know. And I'm using the latest 0.9 version, downloaded today!

admin
Site Admin
Posts: 1303
Joined: Sat Feb 08, 2014 10:39 pm

Re: New user experience (in steps)

Post by admin » Thu Apr 26, 2018 7:10 pm

Hello again, seePyou

Regarding your first new post; Are you sure your source is not 1440x1080 with a 1.333 pixel aspect? This is quite normal so when transkoding to h264 you should make sure the encoder use the same pixel aspect. This is selectable in the h264 encoder. You can force it to "real" 1080 but the video wont be crisper, because your source is still 1440x1080, not 1920x1080.

So your second new post; I cannot reproduce the "right only" issue. FFAStrans does not do mixdown unless you use the "Channel Mapper"-filter. Great care has been taken to make sure FFAStrans maps audio as first to first, second to second, third to third and so forth, regardless of the in/out audio layouts. Maybe you should send a sample of both the 1440 and the audio issue?
And so to the h264 quality. What are your encoding options? Also, I'm not quite sure i understand your your workflow: Is it mp4 -> dnxhd -> mp4 and expecting the last mp4 to look as good as the original? Could you please elaborate and maybe send some sample files?

PS: Are you using the latest patch 0.9.0.4?

-steinar

seePyou
Posts: 33
Joined: Tue Feb 07, 2017 2:54 pm

Re: New user experience (in steps)

Post by seePyou » Thu Apr 26, 2018 9:58 pm

About the resolution: yes I'm sure the resolution is 1920x1080, as that was the video source setting, and because when I saw the 1440 detection I doublechecked with MediaInfo on the original source video confirming it was 1920x1080.

For the second, I am using the latest 0904. The workflow is: record in h.264 20000 bitrate, AMA link in Media Composer, transcode to DNxHD220, export same as source, and then provide the resulting .mov to FFAStrans.
The workflow in there is Detect file *.mov, transcode to h.264 (1920x1080, display aspect same as source, pixel aspect, 1.0, framerate 60, progressinge, 12000 bitrate, 5.2, high, fastdecode, veryslow, and audio Layout 1x2 - despite changing it to 2x1 and saving, this again is 1x2 when I open the h.264 ettings - 44100 and 160) then send this to an export folder.

I just run another short "test" record, and put it through this workflow. I'm sending you the source, exported .mov and resulting .mp4.

EDIT: Actually I could not follow the instructions to upload provided last time. Did they change?

admin
Site Admin
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Joined: Sat Feb 08, 2014 10:39 pm

Re: New user experience (in steps)

Post by admin » Fri Apr 27, 2018 11:00 am

I've seen MediaInfo getting it wrong before. This might be related: viewtopic.php?f=5&t=609

I will send you a private message on where to upload.

-steinar

seePyou
Posts: 33
Joined: Tue Feb 07, 2017 2:54 pm

Re: New user experience (in steps)

Post by seePyou » Fri Apr 27, 2018 1:00 pm

Thank you! Files uploaded.

Source.mp4 - the result of the recording.
MCExport.mov - The export from Media Composer, after the source.mp4 had been AMA linked and transcoded into DNxHD200.
FFAStransProducedMP4.mp4 - what FFAStrans wrote from the MCExport.mov with the settings I specified in my previous post.

admin
Site Admin
Posts: 1303
Joined: Sat Feb 08, 2014 10:39 pm

Re: New user experience (in steps)

Post by admin » Fri Apr 27, 2018 7:16 pm

Thanks for the files. Avid Media Composer report 1440x1080 on the DNxHD file:
2018-04-27.png
2018-04-27.png (523.33 KiB) Viewed 3457 times
And comparing the original and the DNxHD file shows that the DNxHD has lower horizontal resolution than the original:
comparison.png
comparison.png (8.23 KiB) Viewed 3457 times
The upper is the DNxHD and the lower is the original.

So this is why FFAStrans, or rather ffmpeg, says 1440 because it is 1440 with aspect ratio of 1.333, which of course scales to 1920.

-steinar

seePyou
Posts: 33
Joined: Tue Feb 07, 2017 2:54 pm

Re: New user experience (in steps)

Post by seePyou » Fri Apr 27, 2018 7:20 pm

the f...?!?!?!? How does that make any sense?!?!?! Jeez! What a piece of sh... WHY would it do that?!?!?!?! oh god...

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