Archive for the ‘tracking’ Category

Mocha & AE for Tracking & Stabilising

Wednesday, December 19th, 2012

In fact there is an excellent-looking series of tutorials at http://www.mamoworld.com/index.php?option=com_content&view=category&layout=blog&id=42&Itemid=84&lang=en

Sony EX3 Noise & Bits-Resolution & Green-Screen

Sunday, November 4th, 2012

It has been said ( I believe by Alister Chapman ) that there are only marginal benefits from recording XDCAM-EX to more than 8 bits, due to the relatively high noise of this camera, as compared to more typical broadcast cameras.

In my experience, while it was a wonderful step-up from my Z1, certainly it’s recordings are noisier than I’d like, leading me to pretty-process certain footage (using Neat Video denoising plugin to my NLE).  And as a recent project with reasonably well-lit green-screen illustrated, it’s noise in shadows can be a particularly nuisance (much time in post experimenting to work around this).

So I wondered:

  • Even if marginal, to what extent is 10-bit beneficial to EX3 recording?
  • For the EX3, when recording 10-bit, it is also 4:2:2, surely a benefit to chroma keying and resizing (reframing, stabilising/deshaking/tracking).
  • Could the benefit depend on editing workflow?  For example:
    • What if subsequently de-noising (like I mentioned)?
    • Some NLE’s do bits-dithering, hiding the quantisation/banding that would otherwise be apparent from having only 8 bits.

I need to do my own experiments, but for now, here (below) are some results from web-searching…

(more…)

3D Worlds in After Effects

Sunday, January 29th, 2012

I want to put someone inside a virtual world (based on their own paintings), ultimately to be rendered out as a Stereographic 3D movie, but with development in progressive stages/generations, initially based on readily available standard tools and techniques, later proceeding to specialist 3D modelling apps etc.  How to proceed?  Some possibilities that come to mind are:

  • Initial development using only “Planar 3D” as in After Effects
    • I believe this is possible to some extent, using native features of AE.
    • In my earlier post on Adobe Production Premium CS5.5 – Orientation, I noted the existence of Mocha LE, a tracker, included inMocha 2.6, the awesome roto program with a tightly integrated planar tracker.
      • {The planar tracker is (primarily?) ..used as a “roto assist” to speed up the roto process…
        ..and also the tracking data can be exported to a wide variety of programs such as Nuke, After Effects, Combustion and many more for corner pinning, stabilizing, and match move that suite.
  • Subsequent development using “Full 3D” as in Blender etc.  Some relevant previous entries in this blog are:

So I did a web-search: Google: [after effects 3d]

World / Object Creation:

  • http://magazine.creativecow.net/article/building-a-3d-world-in-after-effects
    •  Real (green screened) rap artist and audients, where the rap artist appears on a virtual a giant stage surrounded by replicated audients.
    • Explains the conceptualization, storyboarding, and high-level aspects (no screenshots) of designing a world capable of representation in After Effects, along with building and testing experiences.
  • http://www.computerarts.co.uk/tutorials/fake-3d-after-effects
    • How to make a truck out of a single flat surface with cut-out sections and folds.  Like you would make one out of a single sheet of cardboard (like a cornflake packet).
    • Links to tutorial and support-files.
  • http://www.videocopilot.net/tutorial/3d_city/
    • Similar to the truck, flat sheet (“texture”, obtained from an actual photo, realigned and stretched to remove perspective effect in photo) folded into a 3D building object.
    • Video tutorial and project files are provided.
    • {VideoCopilot.net has both free stuff (tutorials etc.) and pay-stuff.  Well-worth a check-out.}

Tracking:

  • DaVinci Resolve Lite – free
  • http://forums.creativecow.net/thread/2/1003284#1003284
    • Re: After Effects Tracking (by Todd Kopriva, Adobe Tech. Support, on Jul 10, 2011)
      • If you have After Effect CS5, you have mocha—and it’s often the easiest and best way to do tracking for the purpose of compositing.
  • http://forums.creativecow.net/thread/2/1006635
    • Q: “Mocha, or Camera Tracker?” (by andrew donaldson on Sep 8, 2011)
      • {Mocha (LE) comes with CS5.5, Camera Tracker is a third-party add-on}
      • I need to create something similar to this:
      • …. would liked to use similar techniques, especially with the web pages tracking the buildings in city shots.
      • I have tried to use mocha to track the side of a building, but its not proving ideal. Obviously the motion tracker inside AE won’t give me the depth/perspective.
      • So what’s the best way to do this?  … Is Syntheyes/Camera tracker the way forward?
    • A1: (by ben g unguren on Sep 8, 2011 )
      • The general rule of thumb is that Mocha works great if your graphics are ATTACHED to an EXISTING surface (like a logo on the side of a building, or changing the words on a sign). If you’re trying to add something in 3D space (like graphics that “hover” around the building, and seem to actually be there), then you need a 3D solution.
      • Mocha and AE’s internal trackers give you 2D solutions. Mocha’s solutions are a bit more sophisticated, producing corner-point information that mimics 3D, but [this is key] it doesn’t produce a 3D camera.
      • Syntheyes and similar apps will give you an animated 3D camera as well as target points that simulate the world you’re tracking (target points for the ground, buildings, etc — whatever you’ve managed to track and can get a 3D “solution” for). This is A LOT more information than what Mocha or AE’s internal tracking can get you.
      • One other point: when the camera is only panning and tilting (not actually changing it’s own position) then a 2D solution can (sort of) mimick a 3D camera solution. So if all you’re doing is panning and tilting, then you could track that in Mocha, then use that data to animate objects (that are given perspective, for instance). You would be able to achieve a lot of the graphics in the video you linked to using that technique, as they’re using a lot of static cameras.
    • A2: (by Tudor “Ted” Jelescu on Sep 8, 2011):
      • I agree with Ben.
      • In most of the shots from your example Mocha can be used. I suspect that some of those shots where not really video files, but still images cleverly transformed in a 2.5d comp where camera moves can be animated in AE – so no tracker there.
      • Here’s a good tutorial for what Mocha can do:

Generally:

Boris BCC Motion Tracking: Match-Move & Corner-Pinning

Saturday, August 20th, 2011

BorisFX’s BCC can be used as plug-in to various NLE’s, where it can be used for motion-tracking (among other things).

  • From Sony Vegas 10
  • From Avid Media Composer
    • http://www.youtube.com/watch?v=5-V_tdjw2Mw
      • Most Boris Continuum Complete (BCC) filters include a built-in motion tracker which can be used to control the position of the PixelChooser mask or matte or to position the light source of a Light effect. For example, you can attach a light to a moving object in one easy step. In addition, BCC includes powerful, specialized filters that allow you to recover motion data from a clip and then use the data to apply effects. For example, BCC Witness Protection allows you to track a person’s face and apply a mosaic effect to obscure it; BCC Match Move locks the movement of one image clip to another image clip; and BCC Corner Pin allows you to map media to a specific area on a moving object in a media file.

Mocha

Friday, January 7th, 2011

Great video tutorials giving both overview and details of this track/matte/rotoscoping (roto) product (pronounced “Mow-Kah”), at http://www.imagineersystems.com/products/videos.  Example:

  • http://www.imagineersystems.com/videos/steve-wright-mocha-workflow/view
    • Learn mocha: Chapter 2. mocha workflow.  Steve Wright covers the basic mocha track and roto workflow for new users.
  • http://www.imagineersystems.com/what-is-planar-tracking
    • <<<
    • Imagineer’s Planar Tracker doesn’t employ point trackers, but tracks an object’s translation, rotation and scaling data based on the movement of the user defined plane.
    • When you work with the mocha tools, you will need to look for planes in the clip. More specifically, you will need to look for planes that coincide with movements you want to track.
    • The Planar Tracker respects layer priority similar to a camera: Objects in the distance should be lowest in the layer stacking order. Objects closest to the camera should be stacked higher in layers.
    • While the most common planes are flat surfaces, objects in distance or with little parallax form patterns that can be considered successful planes to track as well.  Our customers have been know to get rock solid tracking from unthinkable objects such as faces and spheres.
    • >>>
  • http://www.imagineersystems.com/videos/how-to-shoot-for-planar-tracking/view
    • Great demo of what it can and can’t do, when it’s “overkill” and workarounds (usually in-plane markers or casual objects) for problem-shots.
      • Is “overkill” when subject is fixed and relative motion is only due to camera pan/tilt.