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[Graham Wood]

I would have thought CRF is more significant for video streaming than recording, editing and compressing.

That seems like a weird statement to me. Can you elaborate on why this wouldn apply directly to compressing?

Maybe I'm just weird?

I didn't actually say that CRF wouldn't apply directly to compressing, because it does. I said that CRF is more significant for video streaming which is true. CRF is one of various rate control modes used to encode video. Basically it is a compromise between file size and content quality by determining the number of bits to save/stream per frame. So you can have good quality video with a larger file size or lower quality video with a smaller file size. In the world of home computers it doesn't really matter because most computers will play uncompressed video (.avi) quite happily but obviously the compromise is a huge file size. The problem occurs when you want to burn a 30 min video say, to disk. Then you will have to consider what setting you want to use to encode the video.

CRF is a variable bit rate constant quality mode as opposed to constant bit rate mode. You will be aware that some frames are more complex to encode than others.  A video of the Saturday market in Beirut will give the encoder a lot more work to do than a video of a hedgehog crossing the road. To achieve constant quality the bit rate per frame is going to be different for each frame depending on the content. For home computers all of this still doesn't matter. However, for live video streaming and video on demand variable bit rate encoding becomes a problem because you get bit rate spikes that cause problems at the receiving end. This is where CRF comes into it's own because it uses algorithms to prevent bit rate spiking which is what makes it more significant for streaming as per my statement.

I'll answer your second question with regard to the statement you found odd after I have had a cup of tea.

[Gena Crisman]

OK so, firstly: I understand everything you've said. Perhaps I can point to the reason for my confusion:

"CRF is a variable bit rate constant quality mode as opposed to constant bit rate mode." + "This is where CRF comes into it's own because it uses algorithms to prevent bit rate spiking which is what makes it more significant for streaming as per my statement."

With streaming eg my computer's desktop, my mind goes straight to constant bitrate - it avoids saturating my very fixed maximum bandwidth and I don't care very much about efficiency, so, I think of CRF compared to that as likely to cause problems because it's still quite variable & might saturate. But, you're thinking about CRF vs perhaps CQ? At the very least, a very variable, spiky VBR solution, which means that CRF would solve those spiking problems.

Knowing those different starting points explains the different perspectives, to me, anyway. It would seem the 'most correct' mode for live streaming, if this very reasonable website is to be believed, is CRF with VBV, which is a solution that deals with both the maximum bitrate issue I was concerned about (via VBV) & the efficiency issue of CBR/spiking issues of CQ (via CRF).

To move away from that, I was kinda talking specifically about rendering (and thus, compressing) the video file out from the editor - it happens to provide a CRF input box that, I thought, defaulted to a pretty unideal value. I was worried it was going to add a small extra layer of garbage to people's videos before they ended up on youtube, so, wanted to check that wasn't going to put people off this editor if it was otherwise good for them.

[Anahata]

It would seem the 'most correct' mode for live streaming, if this very reasonable website is to be believed, is CRF with VBV, which is a solution that deals with both the maximum bitrate issue I was concerned about (via VBV) & the efficiency issue of CBR/spiking issues of CQ (via CRF).

Thanks for that link, which has cleared some confusion in my mind. This page on the same site is also useful.

I was kinda talking specifically about rendering (and thus, compressing) the video file out from the editor - it happens to provide a CRF input box that, I thought, defaulted to a pretty unideal value.

Not only that, but you can't select other bit allocation strategies. For H.264 it's CRF only, and for MPEG-4 you can select bit rate only.
KDENLive, for all its faults, provides a wide range of options, like CBR and two pass encoding, and lots of individual parameters inside H.264 that you probably shouldn't fiddle with. (reasonable bet that Olive will offer that eventually, of course)

Also bear in mind, if you are using YouTube:

• Whatever bandwith you have to the internet, others will be different, and you are uploading a video for others to watch.
• YouTube offers a variety of resolutions, so viewers with limited resources (screen size, bandwidth) can usually choose something that works.
• Most important: When YouTube processes your video, it will re-encode and you have no control over what it will do anyway, so aiming for best picture quality (given constraints of upload time, perhaps) seems a good policy, and CRF, with roughly constant perceived quality, looks like a good choice for that.

For more detail on that, see Encoding for YouTube: How to Get the Best Results It's quite old but I think the principles still apply.

[Graham Wood]

Constant bit rate mode for streaming would make sense at face value. Trouble is the encoder needs to make 2 passes to either determine the median number of bits per frame or max bits per frame depending on how you want it/your max bandwidth. That is no good for live streaming because of 2 passes unless you are streaming rendered video. Also MP4 doesn't support CBR mode.

[Gena Crisman]

Well, I don't know what to say really. I guess maybe this all depends on on how specific we're trying to be? Being pragmatic:
a) OBS (Open Broadcaster Studio) uses the term CBR by default.
b) Xsplit uses CBR language by default.
c) Wirecast provdes control settings in terms of Average Bit Rate, so, still bit rate based instead of CRF based, with strict CBR as an option
d) Previously discussed reasonable website seems to be saying CBR would be reasonable for streaming, if wasteful.
Whether these apparently popular streaming softwares actually use actual CBR, or what, I don't know.

At the very least, using CRF for local rendering is very typical in basically all x264 implementing software I've used unless one is targeting a file size. I assume many home computer people will be using for rendering their output video, for example:
via Handbrake https://handbrake.fr/docs/en/1.0.0/technical/video-cq-vs-abr.html
via meGui https://imgur.com/HCZhzgy
via kdenLive https://i.imgur.com/I7Q6PFH.png
via Olive https://i.imgur.com/LX7CzHH.png

I guess Resolve's default h264 output is word quality based, rather than bitrate based, although a limiter is offered.

(AFAIK These are all defaults/or with advanced views open only to show the command line or further details etc, I've not gone fishing for some weird options.)

In any event, if someone's using Olive, the only exposed control of the quality is the CRF value, which seems incredibly sensible. However, I'd suggest they change that CRF value (noting that CRF lower = better quality but larger file size) to a value closer to the low 20s, eg 24 is what I would use, as the default value of 36 seems unusually low quality to me.

[Tone Dumb Greg]

Having spent a bit more time with Olive I want to point out that if, like me, you are more, or less,  mystified by the technical discussion going on about elements of the program that seem to work perfectly well without a lot of fiddling about, but you are interested in anything in the way of useful software that is free, forever, and appears to work very well without a massive learning curve, there is a series of tutorials around that are very helpful and at least one that is not so helpful and must be created by the chap who makes those office software helpfiles, which only help those who already know how how to do it and don't really need much help.

Here's the one that actually does help.
https://www.youtube.com/watch?v=p2t7_6X9m4M&feature=emb_logo

When I first downloaded the software I went for the portable install, because I have had good experiences with these in the past, when I was working at more than one location. Just running stuff off USB keys. I found this portable software  confusing. The version I downloaded seemed to be in the middle of being tested and hardly anything was in its default state. Stuff seemed all over the place and I couldn't find a return to default setting (they exist, for some things, I just never found them). In the end I loaded the 64 bit installed version and all was fine.

When I played with it, without looking at any tutorials I tied myself up in all sorts of knots. Mostly due to assuming things worked in ways they didn't. With the tutorials I found it very easy to get used to using it,  just doing what they suggested. The first half dozen or so videos were the most useful, after that stuff was mostly ok with a suck it and see approach.

One tip is to make sure you have the appropriate tool selected for what you are trying to do. It's confusing if you get it wrong. I wasted a lot of time not realising that I think I had the "ripple" tool (which acts a bit like insert instead of overwrite in text editors) rather than the basic pointer tool. I'm not sure if that's what it was, because I ended up restarting the program from scratch and everything ran right for me.

Like I said, don't be put off by the tech talk, it works fine for common or garden users, who don't need to understand the detail to make it work acceptably.

[Graham Wood]

Whether these apparently popular streaming softwares actually use actual CBR, or what, I don't know.

They probably use CBR 1 Pass.

[Graham Wood]

This is a very informative if long winded explanation of how encoding and compression actually works. https://www.youtube.com/watch?v=vAb7zlbuqFI     The guy reminds me of Bill in the Kill Bill films.

These are the options below that I get for media export:-

[Anahata]

I think you have a later version of Olive than I do. I shall bow out of this discussion, but continue reading with interest.
I have new hardware and software on the way soon, and might return to it then...

[Gena Crisman]

I believe those are screen grabs from Adobe Premier; https://www.premiumbeat.com/blog/pro-tip-exporting-a-finished-video-from-premiere-pro/

[Tone Dumb Greg]

This is the export screen I get. I think I have the latest upgrade [by latest, I mean latest stable distribution April ,2020], but I'm not certain.

[Roger Howard]

I’m in awe of the technical expertise on show. 

[Graham Wood]

Apologies. The screen shots I posted for comparison were of PP not Olive. I should have said as much. I think I will bow out of this thread having caused mayhem and confusion....lol

[playandteach]

Coincidentally, Mayhem and Confusion are my kids' names. They also crash halfway through a task. Take 45 minutes to export the dishwasher. And my wife just won't let me reboot them. But I'm running an older version of dad 2.1, and I think that is well known for incompatibility issues. My wife uses McCleanup, and that is a viable workaround. Mayhem has a 64gb of memory for past comments, and Confusion has a slow start up that can end with the blue screen of death if it's hurried.
Of course, my real kids are lovely - and good company in these times.

[Pete Dunk]

Am I alone in using Open Shot Video Editor? It seems fairly straightforward to use it's free, and it exports to several formats although the output quality is only as good as the source recording of course, particularly sound quality. This was recorded using my old iPad, so the sound could be better, it's pretty much 'warts and all' but it works for me.

[Mcgrooger]

I've read all of this thread and am interested in maybe giving Olive a go to replace WLMM. I even enjoyed reading the techie stuff while understanding hardly any of it! Anahata, Gena and Graham are 3 of my favourite posters even when I've no idea what they're talking about!

I remember the Beeb broadcasting a concert by the Dizzy Gillespie United Nations big band where Dizzy said something along the lines of 'these guys are from all over the world and all speak different languages - they talk and talk all day and nobody's got a damned clue what they're saying.'

[playandteach]

I'm using it now to create online classroom lessons, and it crashed after quite a bit of editing - BUT I reopened it, which it did without any issues, and it had saved the very last thing I had edited, which is another bonus.

[Graham Wood]

I've read all of this thread and am interested in maybe giving Olive a go to replace WLMM. I even enjoyed reading the techie stuff while understanding hardly any of it! Anahata, Gena and Graham are 3 of my favourite posters even when I've no idea what they're talking about!

I remember the Beeb broadcasting a concert by the Dizzy Gillespie United Nations big band where Dizzy said something along the lines of 'these guys are from all over the world and all speak different languages - they talk and talk all day and nobody's got a damned clue what they're saying.'

  Kind of reminds me of my wife, who after 39 years of suffering me, generally responds to my profound (to me anyway) statements with 'That's nice dear', or the occasional 'Good for you'.

[Gena Crisman]

Since I wanted to join in on the fun, I used Olive to make a late submission to a TOTM.

I kinda didn't like it for doing a lot of my 'normal' things I would do, but, I did like it for doing things I would usually avoid doing because of how annoying they'd have been. Like, I would normally skip doing angled text over the bellows. And finding the correct frames to add that text would also be annoying. However, I worry about getting text positioned consistently between videos - I guess basically there are things I do for every video, like, 1s black fade in under the text at the start, 1s black fade out over the text at the end, getting the audio lined up exactly. However the things I need to do just for a given video & need to figure in by eye, or unusual things like make a dissolve edit or combine multiple clips for a multi cam or whatever I'd probably look to this to accomplish them.

So my ultimate review is 'fine, I guess', which in reality is fairly high praise. But my feeling is also 'if I can get this to do the weird math stuff I want, I would probably use this a bunch'.

So, good times all around.

[playandteach]

That's really well done Gena. Doesn't matter what the recording / editing is if you play it that well.