Hi all, new guy here. This being my first post, I figured I'd try to offer something useful to the group, if they want it.

I love my new GoPro to death, but there are times when I don't want the fisheye effect that comes naturally as a result of the camera's wide-angle optics. I've read a tutorial in these forums on how to correct this in the free video editor, VirtualDub, and it works quite well. The only major issue I have found with that is VirtualDub's plug-in to remove the fisheye effect isn't 64-bit compatible yet. That's a shame, since many of us have the hardware and would like to be able to use more than ~3 gigs of ram and make use of the sweet 64-bit cpu benefits while rendering. So a friend and I set out to do the same thing using the venerable Adobe After Effects CS5. I really must thank my friend Pat for his multiple, in-depth trial-and-error sessions with a lot of different footage, subjects, etc to find good general settings. He drove the vast majority of this project, and I followed his lead. He's an AE master and he deserves a lot of credit. After Effects is an expensive program, but I'd say the results are noticeably better than VirtualDub on a pixel-per-pixel accuracy basis (probably due to more complex algorithms to keep pixel smear and distortion at bay). VirtualDub is great for those on a budget, but AE wins the blue ribbon in this project. If you have access to AE and a GoPro, this will really be helpful.

So here it is. I'll explain what to do, then I'll post dl links to my server (hope that's kosher), where you can download the .ffx animation presets I made, just in case you're feeling lazy This is actually a very easy process, considering what AE is capable of doing. If you know AE really well, you'll find this a bit boring, so I apologize in advance. For those just starting out, I'll take things step by step for you.

1) Open AE and start a new composition with the resolution and frame-rate settings that match the footage you're going to import.

2) Import your footage and drag it into the timeline.

3) Look in your Effects Presets window under the label 'Distortion.' You'll find one called 'Optics Compensation'.

4) Dag the Optics Compensation preset into the composition window to the left of the timeline. This window will usually be labeled something like 'Comp 1' or similar at the top. Drop the effect on the clip title. The effect will be added to the entire clip.

5) The project window (upper left corner that has all your source clips in it) will change to the Effects Controls window, showing you the settings for the Optics Compensation effect. Here's where the magic happens.

6) Settings for 720p video:

Field of View: 83.0
Reverse Lens Distortion: CHECK
FOV Orientation: Horizontal
View Center 640.0, 360.0
Optimal Pixels: NOT CHECKED
Resize: OFF

For 1080p video:

Field of View: 63.0
Reverse Lens Distortion: CHECK
FOV Orientation: Horizontal
View Center 960.0, 540.0
Optimal Pixels: NOT CHECKED
Resize: OFF

7) Export your video. Go to Composition > Add to Render Queue. Go to the render queue at the bottom of the screen, and change the export settings to whatever you want. Then click the Render button on the top right of the render queue window. It'll start rendering the corrected video.

8) Done! Go show it off to your friends.

These settings should be a pretty good place to start. Feel free to tweak them as you see fit to get the best balance between lens correction and smearing/distorting the footage. As far as minor adjustments to the above settings are concerned, sometimes I like to tweak the FoV value up or down a bit, or until the fisheye effect seems to be mostly eliminated. Some footage seems to distort if I correct it completely, so I find a happy balance between the two. New guys, be sure not to mess with the View Center values too much or apply a 1080 preset to 720 footage (or vice versa), or it will correct the image off-center and will look awful.

As promised, for those lazy editors that just want to download the presets and apply them without poking around themselves, here are the links. Just right-click and Save As:

720p: http://root.blue10media.com/dl/After%20 ... 20720p.ffx
1080p: http://root.blue10media.com/dl/After%20Effects%20GoPro%20barrel%20correction%201080p.ffx

Anyway, I hope that helps. Let me know if you have questions or suggestions. Best wishes to all, and happy filming!

THANK YOU!!
I play a lot with PP CS5 on a powerful system but have only recently opened AE CS5 to begin checking it out.

So this basically compensates for the fisheye affect, and no actual footage is cropped? This looks really awesome!

a6killa wrote:So this basically compensates for the fisheye affect, and no actual footage is cropped? This looks really awesome!

Some of the footage is cropped with this method, unfortunately. I know cropping is kind of a swear word when talking about high quality video, but in this case I don't think it would be possible without throwing away at least some of the pixels. The GoPro's super wide lens packs too much footage into the edges (mostly near the corners), and if you didn't crop out some of that, you would never be able to get rid of the effect. If you straightened the footage out, but kept it all inside the frame to avoid cropping, you'd be left with an image that was severely 'hourglassed' (black arched gaps with no pixels) on all sides.

This method doesn't seem to mess with the center of the footage to any visible degree, and stretch distortion around the edges seems to be minimal at most. I attribute that to AE's great use of complex algorithms. It basically pulls out the corners of the image past the edges of the frame, and re-interpolates the pixels in areas near the edges so that they stay crisp. When rendered, it just discards the superfluous pixels around the corners that extend past the frame.

Wonderful! Do you have any sample videos we can look at? Perhaps a before and after? Much appreciated!

As a complete novice in After Effects I just tried it. The video I used had too much in the corners (me) but it was super easy and it works. For the right footage it would be very handy! I used R3 and exported it from AE twice, once untouched and again with the 720 settings from charging rhinos' post. Then I put both of those into Premiere Pro, reduced them to 50% and put them side by side.

Schnoidz wrote:As a complete novice in After Effects I just tried it. The video I used had too much in the corners (me) but it was super easy and it works. For the right footage it would be very handy! I used R3 and exported it from AE twice, once untouched and again with the 720 settings from charging rhinos' post. Then I put both of those into Premiere Pro, reduced them to 50% and put them side by side.

^^ Thanks very much for posting your results! i have been so darn busy lately that I haven't had time to do it myself.

I did notice that on your footage, the guy tends to stretch a lot when he gets toward the edges/corners though. I'm noticing that especially the 720 settings can vary quite a bit since it's such a wide lens. The amount of correction to apply seems to depend rather heavily on the subject being filmed (% horizontal vs. % vertical). Not sure exactly why, because it shouldn't. Maybe I need to revise my numbers a little bit. On your specific footage, I might actually reduce that 83.0 value to cancel some of that over-correction out. Not sure exactly how much, as I don't have the source footage, but I don't imagine it would be a huge amount or anything. Another thing to try is to change the Horizontal setting to Diagonal. I've had better luck with a few clips in that mode, but horizontal seems to look better in others. When I get a break from work/school over Thanksgiving, I'll play around with it some more and see if I can zero in the settings better.

Here's another test using the 720p settings...for certain types of clips, its a nice addition (especially for shots of scenery, etc). But, in this case, with action moving away from the camera, I personally prefer the fish-eye look. I was mixed on action coming at the camera, it's really a shot-to-shot thing



And the screen capture, for those curious how much video detail you lose around the edges. Sorry for the large images
Original

After Effects

Thanks for sharing your footage. Yeah, like you said, whether the correction works or not is pretty subject-dependent. Sometimes it's a life saver, other times it looks better left alone. Nice boating, by the way. Looks like a fun drop

HI
I noticed this string is about 64bit systems and After effect CS5 but I was wondering if it will also work on a 32bit system and After effects CS4?