Resolution independence not working?

Hi all

I've just done a quick test on Resolve's resolution independence. I wanted to understand better the impact of Fusion on a timeline that had zoomed-in clips that I wanted to zoom out, and confirming that source resolution would be preserved in Fusion.

But I've hit a problem before I even got to the Fusion test, just using Resolve timelines.

Here's the test I did:

1. I downloaded a 1920x1080 test card from Flickr

2. I used ffmpeg to turn this still PNG into a 1 minute ProRes 422 clip (I wanted to use a video clip for the test in case there exists any difference between still images and videos)

3. I created a 1920x1080 timeline that has four of these video clips, each scaled to 50%, and tiled 2x2. Example Transform settings for one:


4. I created a second 1920x1080 timeline that contains the first timeline, zooming in 2x on one of the test cards.

5. I then compared the second timeline to the original clip, using both the timeline viewers, and the Video Clean Feed.

6. Result: Here's a close-up screenshot of the Source Viewer (left half) and Timeline Viewer (right). The Source Viewer shows a portion of the original video file at 100% zoom; the Timeline viewer shows that same portion, also at 100% zoom, from the timeline that is zooming in 200% on the 50% zoom:


Clearly something has happened here! The vertical lines in the right side of the screenshot are muddied and not nearly as sharp as in the original. This is not "resolution independence"?

If you want to see the full context of the above screenshot, this screenshot shows the full Resolve window, with the 2x zoom timeline on top, and the 4 x 0.5x zoom timeline on bottom, and the two viewers showing the difference between the original image, and the 2x zoom version.

Here are my project settings, which should be at default (I hit Reset to be sure):


And the timeline settings of all the timelines described above (all are the same):



This is rather worrying because I had thought it was a given that Resolve would preserve source clip resolution even when multiple levels of transforms are involved, and I haven't even tried out the interaction with Fusion yet.

Do I have something set-up wrong, or am I misunderstanding something?

Thanks in advance.

I made a standalone project that demonstrates the issue, using the original test card PNG (video wasn't required).

Attached zip contains:

1. TestCard.png - 1920x1080 test card
2. TestResolutionIndependence.drp, containing:
   
   • Imported TestCard.png
   • Timeline: Zoom50pct, containing TestCard.png zoomed 50% and tiled 4x
   • Timeline: Zoom200, containing Zoom50pct zoomed 200%, and panned to focus on one test card.

All timelines are created with default settings.

Do let me know if something is set up wrong!

TestResolutionIndependence.zip

(983.05 KiB) Downloaded 122 times

PS. With this example project I also tested a render, via the Delivery page -> ProRes Master. I wondered if perhaps the scaling issue might not exist when a final render was done. But it does; the render matches what I see in the viewer, with the clear quality loss versus the original source image.

One more post from me: I read the manual chapter again, and noted:
"Center crop with no resizing: Clips of differing resolution are not scaled at all. Clips that are smaller than the current frame size are surrounded by blanking, and clips that are larger than the current frame size are cropped. Keep in mind that this is a good setting to use if you’re importing a timeline from another NLE in which clip resolution adjustments are imported as scaling adjustments. Choosing “Center Crop with no resizing” prevents DaVinci Resolve from “double scaling” clips in imported timelines." (the bold at the end is mine)

It's talking about imported timelines from other NLEs, but I wondered if this might also apply to Resolve's own scaling. So in my standalone example project I tried changing both Timelines to "Centre Crop with no resizing", and also changed the project settings to set this as default.

This initially had a weird result. Looking in the viewer, I could still see the muddied lines, except when I scrubbed through, and then sometimes the lines would seem to flash to something approaching original quality!? Though it still wasn't quite right. I can make a screen capture if anyone is interested.

Regardless, I did another Delivery export, and the resulting ProRes Master still had the muddied lines, so this doesn't help.

This is beyond my job description, but as best I understand it, what you're doing involves transformations which do in fact have resolution-dependent consequences.

Usually, the term "resolution independence" refers to the ability in Resolve to change timeline resolution freely throughout the project, for convenience or necessity, without irreversible or destructive consequences to the footage, and with scaling which adjusts instantly to whatever the current resolution is. Seems to me you're pushing into transformations which do have permanent consequences, and couldn't do otherwise.

This is beyond my job description, but as best I understand it, what you're doing involves transformations which do in fact have resolution-dependent consequences.

Usually, the term "resolution independence" refers to the ability in Resolve to change timeline resolution freely throughout the project, for convenience or necessity, without irreversible or destructive consequences to the footage, and with scaling which adjusts instantly to whatever the current resolution is. Seems to me you're pushing into transformations which do have permanent consequences, and couldn't do otherwise.

You might well be right. However the manual seems to say the opposite, at least that's how I read it.

Page 262:

Every set of transform and sizing parameters and settings that resize clips is combined intelligently, so that the full resolution of a clip’s source media is always used as the source for any transform. For example, if you’re using 8K media within a 1920x1080 project, and you need to enlarge a clip using the Input Sizing palette’s Zoom parameter to 200%, the image is scaled relative to the native 8K resolution of the source, and the result is fit into the current timeline resolution. This automatically guarantees the highest quality for any image transform you make so long as you don’t zoom in past the native resolution of any given clip.

This also applies to situations where, for example, you shrink a clip in the Edit page using the Edit Sizing controls, only to re-enlarge the same clip in the Color page, using the Input Sizing controls. In this situation, DaVinci Resolve is smart enough to do the math combining the project resolution, the Edit Sizing, and the Input Sizing controls so that a single transform is applied to the native source resolution of that clip, giving you the best quality result.

(Bold areas are mine)

Then also on page 269, under section "Edit Sizing in the Cut and Edit Pages":

The transform that’s made via the Edit Sizing controls refers back to either the source resolution of each clip, or the resolution output by the Fusion page if it’s in use.

Okay, but again, these transformations work within any given resolution -- not all resolutions simultaneously.

As best I read the excerpts above, they confirm what I know: the full resolution of the clip is available on a timeline of any resolution. But you're doing other stuff to the clips....

Okay, but again, these transformations work within any given resolution -- not all resolutions simultaneously.

As best I read the excerpts above, they confirm what I know: the full resolution of the clip is available on a timeline of any resolution. But you're doing other stuff to the clips....

I just edited this in to my earlier post, but I'll add it here again for discussion.

On page 269, under section "Edit Sizing in the Cut and Edit pages":
The transform that’s made via the Edit Sizing controls refers back to either the source resolution of each clip, or the resolution output by the Fusion page if it’s in use.

This again, at least how I read it, seems to indicate that Transform controls should always apply relative to the source resolution of the clip, regardless of intermediate transformations applied on the same clip.

The timeline resolution becomes the new native resolution for that timeline if you use it as a clip. So it can't "see" the original resolution of the original clip in a nested timeline.

The timeline resolution becomes the new native resolution for that timeline if you use it as a clip. So it can't "see" the original resolution of the original clip in a nested timeline.

You may be right. Certainly there are a number of things that don't work with nested timelines the way they're advertised.

But the manual clearly states "the full native resolution of the source media you've linked to the clip" which seems unambiguous to me, and it has no caveat about nested timelines. It does have specific caveats about Fusion compositions, stating that a Fusion comp will lock the resolution to whatever resolution is output by the last node of the comp. The impact of Fusion compositions is discussed at length in this part of the manual (chapter 9).

So, the fact that:
a) It specifically says 'source media' (which everywhere else in the manual relates to actual video/image files on disk, distinct from their use in timelines, Color page, etc),
b) The different, non-resolution-independent behaviour of Fusion compositions is described in detailed, but
c) There is no discussion of any such limitations with nested timelines,

all leads me to be sure that the manual is saying that this should work.

Which is not to say it does work that way. But if it doesn't, I really think the manual needs to be rewritten on this subject, because right now it's seriously misleading.

I'd be very grateful to get some confirmation from BMD one way or the other, because this is holding me up at the moment. I have low quality source video which I want to downscale in certain shots, and then want to able to zoom-in-to in other shots. If this is going to cause the shots to be locked to the zoomed-in resolution, then I will have to abandon that plan and do everything in a more complex way, with clips imported at full resolution into every scene timeline and then animating the up and downscales wherever they're required. Much messier than being able to simply nest a timeline at the zoomed-out level, and then zoom in on it as required, which I was sure would work based on chapter 9 of the manual.

When you apply an effect to a Compound Clip, Nested Timeline or Multicam Clip, you're not working on the Source Media, so the manual's comments don't apply.

I hope BMD comments as well, but you can test it easily enough yourself. Decompose the compound clip or nested timeline (right click) and compare results, nested v. unnested.

You're right. Nested timelines are completely non-functional when it comes to resolution independence, image scaling, and all that.

Where, in the intro to Chapter 9, the manual says:
smart enough to always refer back to the source resolution when combining resizing operations to shrink, then enlarge an image for various reasons as you work in the Cut, Edit, Fusion, and Color pages.

It only applies to transformations between pages, like one transformation on Timeline, another on Color. I confirmed that alone does work: scale to 50% on Timeline, then apply 200% scale on Color page, and it looks fine.

Nested Timelines just don't work with multiple resolutions and scaling. The clip scaling and "Mismatched resolution" settings are either ignored completely, or create inexplicable results.

My only option seems to be to render intermediate video at a higher resolution, eg 2560x1440, which I could then import and pan around and zoom in a 1920x1080 timeline.

In the manual they obviously forgot the banner saying "Please be aware that nothing in this chapter applies to a nested timeline or compound clip." That banner is needed in several places in the manual, I think.

Is there some reason these items have to appear as nested? You *are* aware that you can force compound clips and nested timelines to be added to other timelines as decomposed clips? It's just another option.....

If you move around the room, do their eyes follow you?

The clips shown are Fusion Clips. Each Fusion clip contains three source media files, with "Retime And Scaling" set to "Crop" on each, so that Fusion sees the video files at their true resolution (which is 1808x1016 in a project that is 1920x1080 - I don't want the videos to be upscaled before they hit Fusion.)

Having Retime And Scaling set to Crop on nested clips causes the preview problem shown. If I change those clips to Scaling: Fill, the timeline preview displays the contents of the Fusion clip correctly.

The same is true of a nested timeline or Compound Clip, as in this example:


Here's the correct preview for this Compound, achieved by setting the scaling to "Fill" on the three clips contained:


In summary, this is another symptom of Resolve's issues with Resolution Independence, which seems to never work right when any nesting is involved, and sometimes gives truly weird results.

The clip previews are basically a tiny rectangle from the middle of (one of?) the source clips, magnified up to the full frame size, which makes no logical sense.

Is there some reason these items have to appear as nested? You *are* aware that you can force compound clips and nested timelines to be added to other timelines as decomposed clips? It's just another option.....

In the end I went a totally different route, and am doing everything in Fusion. I'm able to get Fusion to see the clips at their native resolution using Scaling = Crop, then I do the manipulations I want in Fusion and output a 1920x1080 image, which matches the timeline resolution. This works fine, save for the scary previews described above.

In this case I wanted to go Fusion anyway as I ended up making a 3D room with camera movements. If I hadn't have done that, then yes you're right I probably could have just decomposed everywhere.

I wanted to use nested timelines because I thought it would give me flexibility. By editing on a nested timeline rather than the source clips, I'd later have the option of making changes in the nested timeline, and knowing it would be applied to all of the edits in one go. Whereas if I just edited the source media file directly on a timeline I'd end up with 50+ clips, and applying one change to all of them would be more work.

For example, all my footage needed to be keyed from green screen backgrounds. I thought that if I used nested timelines I could start editing immediately on the raw footage, then later do the key in the nested timeline and it would immediately apply to all of the edits I made on that timeline, and not to anywhere that I'd cut out.

It just felt cleaner to use nested timelines - a bit like in coding, where you have central functions called from many places, and any edits to that function apply to all callers. Neater and more flexible than having duplicated code.

I fully admit that I'm new to this so there are probably workflow techniques I haven't thought of, and I may well have over-complicated things. But it did feel like every time I came up with what I thought would be a good and efficient method of doing things, Resolve just said "Nope!"

Instead I've ended up learning to love intermediate rendering. I edited my raw media files into a timeline, then when I did the keying I rendered the entirety of the source media files out to new files. That took ages but I left it running overnight so it didn't matter much. Once done, I used Reconform From Bins to replace the original media files with the keyed media files.

At the very least I hope BMD update the documentation to make it crystal clear that the Resolution Independence they speak so highly of is actually applied very narrowly. But much better than that would be if they can get it so it does actually apply everywhere.

Nested timelines and Compound Clips are really powerful, but especially if they provide full functionality. I just wish that a clip was a clip was a clip: that anything that you could do on a media file clip you could also do on a nested timeline, compound clip, Fusion clip, etc.

It should work like "Smart Objects" in photoshop imo.

I recently listened to a Blackmagic technician giving a lecture and saying:

"Davinci resolution independent is great. You can set your timeline setting to HD or even SD and save a lot of resources, making your timeline scrolling much, much smoother. And when you render, it will automatically use the original clip resolution, so you can set the render to 4k even if your timeline is SD."

That is what I remember him saying. When I did so and began to work on Delivery page setting my render to 4k I got a pop-up window saying the timeline resolution is smaller and if I render the image will be rescaled. I was disappointed.

I believe the resolution independence works only while editing, and yes it saves a lot of resources. But once you start rendering, you need to set the timeline resolution to match the output resolution.

That's the way it works.
Smooth editing in HD, for example, and then switching the TL to UHD to be rendered.