Prevent Cropping When Correcting Lens Distortion?

[Whistleboy]

Hello, I need to remove the barrel distortion from footage recorded using a surveillance camera.  I would like to preserve every bit of information from the frame (it will look on the edges like there is major pin cushion distortion).  However, when I apply Effects > Lens Distortion > Curvature -18, the distortion is removed, but pixels are extended outside of my original frame size.  I tried first scaling the video down to 65%, then applying the Lens distortion to see if I could see the aspects of the image that were previously cropped out, but with no luck.  The image now gets cropped at the boundary of the scaled video frame, even though the "canvas" is the original size.

If this cannot be done with Adobe Premiere, I do also have After Effects and Photoshop, but am finding similar problems.  I can't seem to remove the distortion while being able to see ALL of the original pixels recorded by the camera.  Any help is GREATLY appreciated.  Thank you!

[Ann Bens]

You will 'lose' the pixels even if its done in AE or Ps or Gopro Studio.

[Whistleboy]

Thanks for the reply.  Do you mean from a recompression/reprocessing standpoint, or that I won't be able to "see" everything that was captured by the camera's CCD?  I understand that distorting will fundamentally change the pixel x pixel structure of the original video, I just want to keep the distortion within the original dimensions of the footage.

[Whistleboy]

I finally found a way to do this in Photoshop:

1) Open the video > Layer > Smart Objects > Convert to Smart Object

2) Filter > Lens Correction...

3) Under "Auto Correction" tab on the right, uncheck "Auto Scale Image"

4) Go to "Custom" tab and move "Remove Distortion" slider toward the right (pin cushion).

Would still love to know if this is possible in Premiere...thanks!

[jacobr63846378]

hello - did your solution make the image wider?  i am trying to figure out how to do barrel distortion without having the image cropped.

[Whistleboy]

Hmmm, I just tried adding barrel distortion using the Photoshop method I described above and it definitely crops the image (top and bottom extend beyond extents of original size), no matter whether I have the "Auto Scale Image" box checked or not. However, I can scale the movie in the same "Lens Correction > Custom dialog box to ring the top and bottom information within the field of view.  So, yes, I'd say the Photoshop method would work.

[Roei Tzoref]

Op is right (and Ann is right too), Premiere's lens correction only corrects the lens distortion in the dimensions of the footage. there is more pixel information that is available which is cropped by the way this effect works in premiere.

Premiere Before:

Premiere After:

in Ae, a similar type of effect allows you got get more of the image. you can resize the image from within the effect. there will be cropped pixels, but less. this is about 20% more pixels

you can see all the pixels if you want, but this result is probably not what you want:

I don't imagine photoshop has other magic for this type of reverse distortion to save more pixels, but if it did, you can drag the video to photoshop, convert it to smart object and use the lens correction on the video.

[jacobr63846378]

thanks for the response.  let me be as specific as possible to see if we are on the same page or if i am naive.  i want to use a 14mm lens to take digital photos on a canon mark iv.  then undistort the image in post without losing the edges.  i want to do this in a similar way that anamorphic lenses work where they squeeze the image into a tighter frame then desqueeze in post for a wider image.  this image would be wider than a typical 35mm image

[Roei Tzoref]

far from being the lens expert, but anamorphic lens is squishing the image horizontally, this is not the same thing as the extreme distortion were talking about here. you can only reverse the distortion of the image you captured, if it's simple horizontal image then no problems there. if the distortion is not simple horizontal or vertical then you will lose information if you want to straight it out. but this is just common sense to me, I don't even own a camera lets see the experts here share their wisdom from practical experience, maybe there some workflow to get more like what you want.

[andymees@aje]

Hey Jacob

I have a (Mac) plug in called Elastic Aspect which I (re) made for the folks at GoPro that does a horizontal anamorphic like stretch on an image. It's not designed to be a technically accurate lens distortion removal tool (it's more a creative tool for redistributing pixels on a horizontal axis)... still,  if its of any use you can access it via FxFactory in their 'Free'  section.

Elastic Aspect | Life through the Canvas Window

Cheers

Andy

[amkrisis]

Hey, I'm trying to figure out the same thing as you. Any easy solution so far?

Here's my situation:

I shoot in 4K, with an action cam (170 degree lens) so it's a pretty distorted image.

I can correct this in Premiere Pro with Lens Distortion, but that crops the image in and enlarges it.

The thing is, I usualy put bars at the top and bottom of my footage to create an anamorphic look, so I can actually live with the image being pinched it and leaving black where it's pushed inwards, because it would be behind the bars.

So, for me, the zoom isn't needed and is just costing me detail?

I could use AE and use Lens Compensation but jumping into AE just for that seems a bit overkill if I'm honest.

So my question is: is there a way, in Premiere Pro, with our without external plug ins, to fix barrel distortion from a wide angle lens, but NOT have it crop in?

Or am I just worring about loosing detail that won't be than noticable (I do watch in 4K)?

It just seems a waste to have something cropped in to be straightened, and then but bars over it? That way I loose some of the footage on the left and right hand side as well?

[jacobr63846378]

I spent hours if not days on the same question and realized that the only

way to do it would be to create a custom curved screen exactly matching the

particular lens that you have otherwise all the stuff in the periphery just

looks weird

[KellyG-B]

Sadly, the only solution I've found that retains all of the original captured image is the method using Photoshop I outlined above.  If I find any other solution I will certainly post here...

[George Day]

Hi All,

I know this is an old thread but I'd like to throw my solution to this in to the mix for others that stumble on it.

I hit the same problem - and I've fixed it in the past by taking it out to AE and then back in to Prem - but the Dynamic Link slows things down a little and it's just an extra messier step I'd like to avoid. Here's what I do now;

Say my source footage that I want to distort is 1920 x 1080 25p.

1. Create a new Sequence (e.g. Footage NEST), at a higher resolution to that of the source footage, say 4K, in my case 3840 x 2160 25p.

2. Place my source footage into the new sequence - leave scale at 100 - do not scale it up to fill the frame - just let it sit in there with black space around it.

3. Place the new sequence (Footage NEST) into my original 1920x1080 timeline and set the 'Scale' to 100. Now, it appears in the timeline without any black space or extra crop, as if it was the original footage.

4. Apply the 'Lens Distort' to the new sequence (Footage NEST) and set curvature as desired.

Now all the original data should be retained, so you can scale it and/or change position and use that extra image data.

Hope this makes sense/helps someone out!

[creativeiq]

This helped me out - thank you!

I'm correcting aerial footage from a drone and the distortion is massive.

Don't know how you figured this out, but I'm glad you did 🙂

[Espire VR23031752rsbc]

Legend!! Thankyou! This is a great workflow. 

[Turrican101]

I don't understand why there's an option in AE to distort to the inside or outside of the content box, but in Premiere this is missing... I would like to distort to the inside and then crop to 21:9 format. So i could use the whole width of the original and only have to crop the irrelevant corners. In AE no problem, in Premiere not possible...

[R Neil Haugen]

The code and structure of PrPro and Ae are quite different. And with the design feature of that Dynamic link between them, they don't see why every tool of Ae needs to be recreated in PrPro. As that is what the link is for.

In general I tend to agree. I'd rather have them working on extending their toilets rather than duplicating them.

Neil

[Turrican101]

They don't need to recreate the tool, it's already there. But only one option missing, where you can set to distort inwards instead of outwards.

It wouldn't matter if i could resize the content, not just the box where the content is in. If i resize the video it stays cropped instead of showing the outer rest.

[R Neil Haugen]

They still couldn't copy the code from Ae into PrPro for that ... it would be development within PrPro. So yea, they'd need to re-create that part.

Neil

[Ann Bens]

Or use GoPro Studio.