Blackmagic Forum

Davinci Resolve Studio 15.3

In 'Deliver', after adding a job to the queue and clicking 'Start Render', the exporter scrubs through the entire timeline while exporting.

Any way to disable this?

TIA

No

I have discovered errors in the edit by watching the render preview.....
It is useful.....
IMHO

Well, I have projects that take 30+ minutes to render so I wouldn't sit at my computer and watch the preview while it's rendering. Considering I would have already watched the final product from the timeline multiple times before rendering, I would have to watch it again after the render to verify the render.

Also, the render would be significantly faster if it didn't display a preview while rendering. This is a fact.

This would be the first editor I have used that didn't have the ability to turn preview off; odd decision not to allow this...

CompBoy wrote:Well, I have projects that take 30+ minutes to render so I wouldn't sit at my computer and watch the preview while it's rendering. Considering I would have already watched the final product from the timeline multiple times before rendering, I would have to watch it again after the render to verify the render.

Also, the render would be significantly faster if it didn't display a preview while rendering. This is a fact.

This would be the first editor I have used that didn't have the ability to turn preview off; odd decision not to allow this...

It will not be faster: you can saturate the disk bandwidth, you cannot go faster than that.

"Also, the render would be significantly faster if it didn't display a preview while rendering. This is a fact."

Where is your proof of this?

I agree with your line of thinking. At one point, I had the same thought.

Which again, leads me to ask...where is your proof that displaying the preview is slowing everything down?

waltervolpatto wrote:

CompBoy wrote:Well, I have projects that take 30+ minutes to render so I wouldn't sit at my computer and watch the preview while it's rendering. Considering I would have already watched the final product from the timeline multiple times before rendering, I would have to watch it again after the render to verify the render.

Also, the render would be significantly faster if it didn't display a preview while rendering. This is a fact.

This would be the first editor I have used that didn't have the ability to turn preview off; odd decision not to allow this...

It will not be faster: you can saturate the disk bandwidth, you cannot go faster than that.

Can you clarify what you mean?

"saturate the disk bandwidth" - ??
"you cannot go faster than that" - what he is saying is that he believes (actually he said it's a fact) that the preview is slowing things down. It sounds as if you're saying that it is limited, so it will go as fast as it will go, no matter what. But I guess it doesn't address his point that (he believes) without the preview, it will be faster.

Dave Andrade wrote:Which again, leads me to ask...where is your proof that displaying the preview is slowing everything down?

It's definitely slowing it down, as the system has to do extra work to generate that preview, how much extra work is open to debate, and would be heavily situation & hardware dependent.

If you have more than enough CPU & GPU for the render, then it probably has almost no effect. If your almost at your systems limits, then it might have a very notticable effect.

It's also worth noting that 16 looks to have added this feature.
viewtopic.php?f=21&t=88830

Ability to minimize or disable viewer updates during rendering

Missed that!

Thanks for pointing that out!

For the record, I wasn't trying to be sarcastic towards another member, and it makes logical sense that it would slow the system down, but I made my comment because it's easy to say something is fact, but proving it (for the sake of validation) is a different story.

Glad to hear they implemented the option to remove it, if one chooses.

Since I cannot turn previewing off, I can't really prove it can I?

Although it sounds like we can test it in 16. I'm waiting until the official release to try it.

Dave Andrade wrote:"Also, the render would be significantly faster if it didn't display a preview while rendering. This is a fact."

Where is your proof of this?

I agree with your line of thinking. At one point, I had the same thought.

Which again, leads me to ask...where is your proof that displaying the preview is slowing everything down?

It depends on the design. If you show frame before encoding then it's not necessarily any faster (although still can be eg 1%). If you encode then decode and show this in preview then turning preview off definitely can speed up encoding.

Just tested. With or without the thumbnails and with or without the preview window updating. and with or without both, render time does not change, so it is having no impact.

Charles Bennett wrote:Just tested. With or without the thumbnails and with or without the preview window updating. and with or without both, render time does not change, so it is having no impact.

Like I mentioned initially, it depends on how capable you're hardware is, if you have any bottlenecks, what kind of video you are working with, and what you are doing to it.

Not to mention its only an initial beta, so who knows how much clean up and optimization BM has done.

Also, someone mentioned earlier that the storage bandwidth (hard drive) would be a bottleneck. Every computer ever made has, and will have, this issue unless storage is invented that operates at the same speed as the CPU. Even RAM doesn't operate at the same speed as the CPU. Disk storage is always the bottleneck. Even with M.2 PCIeX bus drives, they are operating at a fraction of the CPU pool speed.

In any case, I noticed what others have noticed: when rendering, the application uses about 30% of the CPU/memory resources (1080p). With that being said, there is plenty of bandwidth for a preview, while rendering, that will not slow the render down. But I'm going to say that other editors I have used are nearly maxing out the resources so adding a preview on top of that will indeed slow the render down. That would certainly explain things.

But yup. Totally depends on the app and resources available.

This honestly makes no sense. Of course having a live, real-time preview during rendering increases the render time and system resources. This is why EVERY other video editing software does NOT show a preview during rendering (except Adobe Premiere; which can be disabled with the CAPS Lock key).

This is really a feature that should be added to Davinci Resolve....although I can't actually get Davinci Resolve to work on my computers, it seems to be an extremely awesome piece of software.

Live preview doesn’t need to slow down export. It all depends on the app design. Resolve about always builds final frame on GPU and then passes it to export engine. Fact that it displays this frame to monitor is not going to hit performance in meaningful way.
Some apps do actual export (encode) task and then decode frame back and display it. Such a process can massively hit performance depending on the export format.

While I agree with Andrew that renders aren't likely to speed up significantly, this feature actually has been added to Resolve since the original post.

In the Viewer menu, Updates During Renders...

Resolve changed quite a lot recently in some cases.
When you use it more like a transcoder ( so without any source adjustments) it seems to now bypass main engine and pass data directly to export engine. In such a case a wish to display video may affect performance more. Another case is use of eGPU which can hit performance a lot when you try to display final data through it.

Since versions 16 you have three options in the delivery page:

[upgrades during renders] — [off]/[minimal]/[on]

With the default being [minimal]

Does this solve the issue?