reply to post by coolottie
While a detailed pixel-level video analysis of the
Flash Video/Youtube-style File is somewhat inconclusive
because too much video compression has been applied,
I CAN DO physics-based analysis which includes
lighting, motion and object & surrounding surface
The things I detail here will have the unfortunate effect
of giving the "nasty" people tips on how to make better fakes
BUT this post will EXPOSE the things one should look for.
Pixel level analysis requires access to the original DV/HDCam,
Flash Memory Card or Broadcaster footage so I can find the
common mathematics of an improper colourspace conversion
...i.e. overly saturated RGB to YCbCr or YCC conversions
which would indicate 3D Animation rendering. Much modern
video footage is shot using technology called CMOS camera
chips (Complementary Metal Oxide Semiconductor) or CCD
(Charge Coupled Device) which have a very distinct
mosaic-based colour filtering pattern called a Bayer Filter:
See CMOS Sensor:
See Charge-Coupled Device:
See Bayer Filter:
The WAY an image is captured via the hardware
can tell me if an image has been modified.
BY doing a inverse de-mosaic on original video
so I can check whether the Bayer mosaic pattern
I will see regarding the positioning, brightness
and hue of each pixel is CONSISTENT with
a Bayer (or other) image sensor type video
If I KNOW the original camera that was used,
I can then find out the TYPE of CMOS or CCD sensor
that was used and then COMPARE whether the
Bayer-to-RGB or Bayer-to-YCbCr colourspace
conversion specs of that camera MATCH what
I SHOULD see in the video file that
was supposedly shot with that camera.
If portions of an image DO NOT have the typical
Bayer-pattern consistent with that camera model
...that TELLS me the image is modified.
There are other image sensor patterns used
in addition to Bayer, but those I can also
account for because of me knowing the
original Camera type for comparison.
Various types of cameras also use specific file formats
and video compression formats that SHOULD contain
consistent video compression artifacts and video noise
patterns IF the original video is unretouched.
I can do a byte-by-byte analysis of the video compression stream
AND the audio stream to see if I see consistent macroblocking
and video/audio noise reduction patterns that are part-and-parcel
of the compression type. MPEG2, Wavelet and Motion JPEG/DV
file formats of modern video cameras have VERY SPECIFIC
tell-tale signs of compression which means if a 3D object was
RENDERED ON TOP of that footage I could see the tell-tale
edge fuzziness and macro-blocking patterns of an alpha-channel
overlay technique that comes from a typical type of
3D animation or Video FX software.
Video FX software and 3D animation programs also have
DIGITAL SIGNATURES that signal HOW they overlaid
an object on top of moving video and HOW they rendered
that object to make it look real.
If I see the colour banding on a flat or curved surface that
is consistent with using single-precision floating point numbers
within the RGB-to-YCC/YCbCr colour space conversions,
I can TELL it was done with older versions of BLENDER.
If I see the levels of brightness or hue in blocks of pixel
that are consistent with working in Adobe Photoshop's
sRGB colour space I can then tell that After Effects,
Premiere or Photoshop were involved SOMEHOW!
If I see 3D animation techniques such as an INVERSE SQUARED
decrease in brightness on the edges of say a StarShip...that would
be consistent with a rendered 3D animation and Alpha Channel-based
See more 3D graphics background info:
See Alpha Channel Compositing:
See Chroma Key Compositing:
See YCrCb Colour Space Definitions:
See RGBA Colour Space Definitions:
See 3D Computer Graphics Ray Tracing Techniques:
See Real-World Optical Ray Tracing Technqiues
See tell tale signs of Gourad Shading:
See tell tale signs of Phong Shading:
See tell tale signs of Specular Highlighting:
See optics based REFRACTION effects:
See 2D and 3D Animation based TWEENING techniques:
See Available Free and Commercial 3D Animation Software:
See 3D rendering techniques:
See Renderman SHADING Language:
The above links should give you a background on things
to look for that are SIGNS of typcial 3D animation and rendering.
The WAY an object is overlaid on top of a video
is a tell-tale giveaway that it is FAKE if it appears
within video that has lots of noise, or random artifacts
when the surface of the ships seems too smooth, too perfect
and too computer-graphicky. The types of Specular Highlights,
Phong or Gourad shading used on smooth or curved surfaces
or the tell-tale signs of shiny Ray-Tracing techniques within
certain 3D animation programs (i.e. Don't Make it Good!
Make it Shiny!) special effects filters, tell me WHAT TYPE
of rendering algorithm was used and THEN i can match that
like a fingerprint to a specific 3D rendering program.
Other things I look for are the breaking of certain laws
of physics such as NOT seeing the movement of clouds
consistent with a large object moving through it.
I should see heat shimmer, refraction, difraction, water vapour
refraction, outline fuzziness, lens flares, and other video artifacts
which NORMALLY show up in REAL VIDEO FOOTAGE!
In this video, the tell-tale signs of inconsistently applied
CAMERA LENS and OBJECT MOTION PHYSICS
tells me that the footage see is a 3D spaceship
rendered using alpha channel compositing.
Rotating objects wobble slightly, sunlight shines and
highlights metallic objects and light shimmers through
atmosphere and reflects off edges in VERY SPECIFIC
WAYS in a REAL IMAGE...which I DO NOT SEE
in this video!
There isn't any need to do a pixel level analysis,
its the motion and lighting aspects that give away
the FAKE nature of this video and the fact that
I especially DO NOT SEE cloud displacement
and tell-tale signs of atmospheric WAKE that
would have a REAL OBJECT float through
our skies...Hey! Even Field Effects powered
starships leave tell-tale signs of light-bending
around a gravity well...which I also don't see here!
SO IN MY HUMBLE OPINION....IT'S FAKE!
P.S. Aliens Don`t FAST Rotate Their Larger Ships --- SO THE VIDEO FOOTAGE IS FAKE!