Monday, May 29, 2006
 The following is from a letter to BYU Prof. Steven Jones, obtained by Total911.info contributor valis. While interesting, it perhaps does not confront head on the issue of why there are so few frames per second in this video. It is possible that the security cameras recorded the stanbdard 30 frames per second, but the Pentagon only released one or two frames per second, frames cherry-picked to reveal as little information as possible.
Full text available at GNN.tv May 18: "Dear Prof. Jones,
[T]he totally new video, rather than the older one of which 5 frames were already in the public domain.. . . is constructed of 5,756 frames of pixel size 480 by 360. Oddly, every 32 frames are nearly identical. I say nearly, because while each group of 32 frames certainly contain no movement and were certainly derived from the same original CCTV output frame, by running the video through frame differencing you can easily detect small jpegging artifacts and noise within the 32 frame groups. Further, the video occasionally shifts up or down by a tiny amount, in a seeming random fashion. Finally, there is a faded black border around the frames. These are all clues to the probable history of this video, and how it was constructed.
PROBABLE ORIGIN
Most CCTV cameras in the US produce a very similar output to regular TV video format, and despite advances in digital technology, most are still analog. The camera position here seems to be in a non-critical role at the entrance to a staff car park. This, coupled with the faded black boundary indicated that this video was probably produced by a regular NTSC Interlaced signal recorded onto an Analog medium such as a VHS cassette. This analog video would then have been digitised, processed, and released to Judicial Watch on the CD-ROM.
NTSC is interlaced, meaning that alternate rows of pixels are refreshed at twice the quoted frame rate. So that, with a NTSC frame rate of just under 30 fps, old and even pixels rows are alternately refreshed at just under 60Hz. To save video tape, Analog cameras only record one frame every second or so, and that seems to be the case here. (Modern digital CCTV systems commonly record at a variable framerate, depending on activity in the scene. The fact that this did not happen here is further evidence that the system is an older Analog CCTV)
When digitizing the video, you have the choice of deinterleaving the frames to produce a video of 60Hz, but with half the vertical resolution. One disadvantage of this is that because alternate frames are produced by pixel positions with a slight vertical offset, the digitized video will vibrate up and down in an annoying way. However I believe that this video was produced in this way because at irregular intervals, the video can be seen to shift up and down by approximately one pixel. The irregularity indicated that the video’s producers cherry-picked certain frames from either deinterlace output, and built them into one video.
DIGITIZED, BACK TO ANALOG, AND DIGITIZED AGAIN?
[...]
I propose that the original 179 CCTV output frames were digitized, deinterleaved, manipulated extensively, recombined into one video and then recorded back onto a VHS (or other analog format) cassette. This version was then digitized again and released to Judicial Watch.
I do not know why they would do this, but it is my best explanation of the processing anomalies of this video.
The important conclusion is that this video has a long history. I suggest that the Pentagon be asked to release the original, analog and unedited version of this video, along with the 84 other videos they hold.
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