[meteorite-list] two fireballs

From: Jodie Reynolds <spacerocks_at_meteoritecentral.com>
Date: Mon, 25 Feb 2013 20:38:17 -0800
Message-ID: <131920811.20130225203817_at_spaceballoon.org>

Thanks Murray,

This is definitely one of the more interesting videos I've seen.
Very raw, high resolution, and the camera was just in the exact right
position to show us why there were two lurking trails.

I really enjoyed this video. Watching the bolide approach in the
reflection of the little Sport-Cross (VW?) [Frames 15-44 inclusive]
with that kind of detail just isn't something a standard-definition
camera would have offered. There was enough attenuation in that
reflection from the tint that the iris freaking out didn't impact the
value.

Anyway - my pleasure! That's got to be a once in a lifetime
opportunity!

--- Jodie

Monday, February 25, 2013, 8:18:41 PM, you wrote:

> Hi Jodie:

> Fantastic images! Thanks for the converted files. I would never have
> realized that there was so much there!

> Murray

> On Mon, Feb 25, 2013 at 9:01 PM, Jodie Reynolds
> <spacerocks at spaceballoon.org> wrote:
>> 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
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>>>>
>>
>>
>>
>> --
>> Best regards,
>> Jodie mailto:spacerocks at spaceballoon.org
>>
>> ______________________________________________
>>
>> Visit the Archives at http://www.meteorite-list-archives.com
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-- 
Best regards,
 Jodie                            mailto:spacerocks at spaceballoon.org

Received on Mon 25 Feb 2013 11:38:17 PM PST