[meteorite-list] two fireballs

From: Murray Paulson <murray.paulson_at_meteoritecentral.com>
Date: Mon, 25 Feb 2013 21:18:41 -0700
Message-ID: <CADHggP1NjrVgtymg7TmASbRmPEB=6ZT4JqUgoA4F0PptCRz4pQ_at_mail.gmail.com>

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
>>> 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
> Meteorite-list at meteoritecentral.com
> http://six.pairlist.net/mailman/listinfo/meteorite-list
Received on Mon 25 Feb 2013 11:18:41 PM PST


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