[meteorite-list] two fireballs

From: Joshua Tree Earth & Space Museum <dorifry_at_meteoritecentral.com>
Date: Tue, 26 Feb 2013 16:28:41 -0500
Message-ID: <AEBAED2595C8485ABAE6D29BF798935A_at_terryPC>

BAM!

Phil Whitmer
Joshua Tree Earth & Space Museum
----- Original Message -----
From: "Jodie Reynolds" <spacerocks at spaceballoon.org>
To: "Steve Dunklee" <steve.dunklee at yahoo.com>
Cc: <meteorite-list at meteoritecentral.com>
Sent: Monday, February 25, 2013 11:01 PM
Subject: Re: [meteorite-list] two fireballs


Hello Steve,

I have more than 70 patents in the space in nineteen countries.
I'm the Chief Technology Officer for a company that designs and sells
digital video surveillance equipment -- I sell close to 30,000 systems a
year.

My masters degrees are in mathematics and electrical engineering with
an emphasis on optical physics, and I've been in the digital video
space inventing compression algorithms for more than two dozen years.

So, yeah, let's go ahead and investigate my "snow job", shall we?


Most cheap dash cameras being imported now are 1080p/30. 1080p/20 is a
favored option to maximize SD card usage. They differ from ATSC in
that they don't generally support 1080p/60.

For Example:
http://www.amazon.com/1080P-Dashboard-Camera-Accident-Vision/dp/B0099KGDQ2
http://www.rakuten.com/prod/new-real-hd-1080p-h264-5m-car-dashboard-camera-recorder-accident-dvr/225640553.html?listingId=174887992
http://www.espow.com/product_info.php?products_id=50672&currency=USD&gsc=googleshopping&gclid=CMfrtJmH07UCFYKDQgodMSoAAQ

http://www.ebay.com/itm/Full-Car-DVR-HD-1080P-Cam-Recorder-Camcorder-Vehicle-Dashboard-Camera-F900LHD-/251182177426?pt=US_Surveillance_Digital_Video_Recorders_Cards&hash=item3a7b9fdc92
http://www.ebay.com/itm/Car-DVR-HD-1080P-Cam-Recorder-Camcorder-Vehicle-Dashboard-Camera-Hot-Sale-/330840799556?pt=US_Surveillance_Digital_Video_Recorders_Cards&hash=item4d07a5f944
http://www.ebay.com/itm/GPS-FULL-HD-1080P-Car-Camera-DVR-GPS-Logger-Vehicle-Black-Box-Video-Recorder-/320741840995?pt=US_Surveillance_Digital_Video_Recorders_Cards&hash=item4aadb41863


No dash cameras have been produced for public consumption at sub-D1
in at least five years. Mobile DVRs will often offer CIF for
multiple channel recording however (a limitation of the NTSC or PAL
scan converter).

640x280 is a non-existent format, as that would be 0.4375, not ending
on a byte boundary. You're thinking of 240 lines. And it wouldn't be
640 (square pixels), it would be 704. Or perhaps you're thinking of
SIF in a 525 line domain, which would be 352x240, or CIF in the 625
line domain (352x288).

The container format was, in fact, MP4. The codec used for
compression was AVC. AVC is aka MPEG4 AVC (Advanced Video Codec),
which is also known as h.264 **see below.

The original submitted video was 1080p. Youtube has offered 1080p
since 2009.
http://youtube-global.blogspot.com/2009/11/1080p-hd-comes-to-youtube.html

We can see the offered streams from youtube as/per:
http://www.spaceballoon.org/available-streams.jpg


There is no such video container or codec as "pmg" that I'm aware of -
 Would you provide the FOURCC for that?

 My stills are in PNG (Portable Network Graphics) as I noted
originally. __MPG__ is the Motion
Pictures expert Group [of which I've been a member off-and-on as well
as on several working groups over the years), and MPEG1, MPEG2, MPEG4, MPEG
AVC (aka h.264,
aka MPEG7 aka MPEG4 Layer 7, etc.) are all possible with additional
qualifications of things
such as differing levels of motion prediction, different transport
layers, and different containers.



Now, would you like to say anything else incredibly stupid, or would
you like to apologize for attacking me in your blind ignorance and we
can just let it go?




**Format : MPEG-4
Format profile : Base Media / Version 2
Codec ID : mp42
File size : 348 MiB
Duration : 10mn 1s
Overall bit rate mode : Variable
Overall bit rate : 4 860 Kbps
Encoded date : UTC 2013-02-14 04:06:40
Tagged date : UTC 2013-02-14 04:06:40
gsst : 0
gstd : 601210
gssd : BADC23F61HH1361841351562120
gshh : r1---sn-p5qlsn7z.c.youtube.com

Video
ID : 1
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High at L4.0
Format settings, CABAC : Yes
Format settings, ReFrames : 1 frame
Format settings, GOP : M=1, N=40
Codec ID : avc1
Codec ID/Info : Advanced Video Coding
Duration : 10mn 1s
Bit rate : 4 714 Kbps
Maximum bit rate : 9 011 Kbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 20.000 fps
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.114
Stream size : 338 MiB (97%)
Tagged date : UTC 2013-02-14 04:06:50

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : LC
Codec ID : 40
Duration : 10mn 1s
Bit rate mode : Variable
Bit rate : 144 Kbps
Maximum bit rate : 150 Kbps
Channel(s) : 1 channel
Channel positions : Front: C
Sampling rate : 44.1 KHz
Compression mode : Lossy
Stream size : 10.3 MiB (3%)

Encoded date : UTC 2013-02-14 04:06:48
Tagged date : UTC 2013-02-14 04:06:50








Monday, February 25, 2013, 6:43:34 PM, you wrote:

> HI Yall
> I have a problem with this paragraph.


> The following is my disassembly of that video with strictly the
> relevant frames. No post-processing has been done, simply brought
> the original MP4 container down, decompressed the 1920x1080p/20fps
> transport into raw 8bit 4:2:0 YUV frames [the native frames], and
> mapped them into lossless 24bit PNGs.

> Most dash cams are 15fps and 640x280 not 1080p hd high resolution.
> especially considering the highest resolution youtube uses is 720p.
> Nice snow job. was pmg not mp4
> Cheers Steve


> --- On Tue, 2/26/13, Jodie Reynolds <spacerocks at spaceballoon.org> wrote:

>> From: Jodie Reynolds <spacerocks at spaceballoon.org>
>> Subject: Re: [meteorite-list] two fireballs
>> To: "Chris Peterson" <clp at alumni.caltech.edu>
>> Cc: meteorite-list at meteoritecentral.com
>> Date: Tuesday, February 26, 2013, 1:51 AM
>> [Note: frame references refer to my
>> attached disassembly]
>>
>> Hello Chris and all,
>>
>> I agree: I don't see any impact event, certainly no
>> shockwave is visible in
>> the bright frames.
>>
>> I see the object of interest traveling away from the camera
>> on a
>> steep angle and, between blooming and DCT errors, obscuring
>> itself.
>> The digital iris tries its darndest to figure out what to do
>> with
>> itself, and actually makes some pretty good decisions around
>> frame 63
>> giving us some pretty nice images.
>>
>> There certainly does appear, however, to be more than one
>> parallel
>> path suggesting more than one component of the mass by frame
>> 65/66. There's also some
>> pretty good sized component being shed earlier.
>>
>> Chris, have a look at frames 64-80 in this disassembly to
>> see if you
>> concur.
>>
>> The following is my disassembly of that video with strictly
>> the
>> relevant frames. No post-processing has been done,
>> simply brought
>> the original MP4 container down, decompressed the
>> 1920x1080p/20fps
>> transport into raw 8bit 4:2:0 YUV frames [the native
>> frames], and
>> mapped them into lossless 24bit PNGs.
>>
>> The video as I pulled it is an MPEG 4.2 container with AVC,
>> High L4.0 Profile, VBR _at_
>> 4.714-9.011Mbps, 20fps constant, progressive 4:2:0 YUV 16:9
>> encoding.
>>
>> One reframe, GOP M=1,N=40.
>>
>> The original timecode is branded: UTC 2013-02-14 04:06:50,
>> but
>> there's no way of knowing how accurately the DVRs clock was
>> maintained.
>>
>>
>> 105 frames contained, ~102MB here:
>>
>> http://www.spaceballoon.org/chelyabinsk-meteor-frames-from-dash.zip
>>
>> "Fair Use" is assumed, and all rights are retained by their
>> original
>> holder.
>>
>> Best Regards,
>>
>> --- Jodie
>>
>> Monday, February 25, 2013, 5:05:46 PM, you wrote:
>>
>> > You are confusing optical aberrations for what is
>> happening physically.
>> > Not only are there no components of the fireball
>> colliding with other
>> > components, but no shock wave structures are apparent,
>> either.
>>
>> > Analyzing very bright point sources in video is
>> difficult, as there are
>> > lens reflections, lens distortion, and various sensor
>> artifacts. It's
>> > hard to actually locate the center of the meteor from
>> such data.
>>
>> > Chris
>>
>> > *******************************
>> > Chris L Peterson
>> > Cloudbait Observatory
>> > http://www.cloudbait.com
>>
>> > On 2/25/2013 5:56 PM, Steve Dunklee wrote:
>> >> http://www.youtube.com/watch?feature=endscreen&v=dBvotWfR3j4&NR=1
>> >> 26 seconds in on this video you clearly see two
>> fireballs with the second one catching up to and impacting
>> the first one.
>> >> The first one makes a shockwave
>> and area behind it with less air pressure. the shock wave at
>> over 10k mph is like a brick wall and acts like a funnel.
>> Like following an 18 wheel semi truck too close to save gas.
>> when the truck hits its brakes the suv behind it impacts.
>> and kaboom. Meteors donT HAVE BRAKES AND CANT CHANGE
>> VECTORS. So when the first piece is slowed down the
>> following ones catch up.
>> >> Cheers
>> >> Steve Dunklee
>>
>> > ______________________________________________
>>
>> > Visit the Archives at http://www.meteorite-list-archives.com
>> > Meteorite-list mailing list
>> > Meteorite-list at meteoritecentral.com
>> > http://six.pairlist.net/mailman/listinfo/meteorite-list
>>
>>
>>
>> --
>> Best regards,
>> Jodie
>> mailto:spacerocks at spaceballoon.org
>>
>> ______________________________________________
>>
>> Visit the Archives at http://www.meteorite-list-archives.com
>> Meteorite-list mailing list
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>>

-- 
Best regards,
 Jodie                            mailto:spacerocks at spaceballoon.org
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Received on Tue 26 Feb 2013 04:28:41 PM PST