[Lex Computer & Tech Group/LCTG] Computer graphics question

[Tony]

Hi Jonathan,

This is a follow up to my call earlier today. MATLAB-2021 has a script 
(VideoReader.m) that I believe will address your needs. I just hope that 
you have access to MATLAB-2021 through your MIT connections.

Following is an excerpt from my friend's email in response to my inquiry 
about the 3D capability (x-y pairs vs time/frames):

"

My version of MATLAB (2021a) has a function called "VideoReader". It 
reads in an MP4 file and returns an object with describing the frames 
and various other properties. I have only tried the example provided by 
MATLAB, so I don't have a lot of knowledge about this feature. Using the 
example from my MATLAB installation, I've made a script that plays the 
example MP4 file frame by frame: vidObj = VideoReader('xylophone.mp4'); 
vidObj.CurrentTime while(hasFrame(vidObj)) frame = readFrame(vidObj); 
imshow(frame); title(sprintf('Current Time = %.3f sec', 
vidObj.CurrentTime)); pause(2/vidObj.FrameRate); end The file 
"xylophone.mp4", comes with the MATLAB installation This is all Windows 
based, so I don't know where MACs have a default installation for a user.

"

If I can be of any further help, please let me know.
Cheers,
Tony Galaitsis
781-718-7847

==============
On 8/1/21 12:31 PM, Tony wrote:
>
> Jonathan,
>
> I have something that with some modification might help you get that 
> information.
>
> _/*Question*/_: Youtube videos list the running time (low-left part of 
> frame) at rounded-off 1-sec intervals. Would the 1-sec tolerance be 
> sufficient for your needs?
>
> _/*Comment: */_My tool is MATLAB-based but we can work around that.
>
> Please call me off line to discuss, if you have not found an alternate 
> solution. I will follow up with a call, too.
>
> Tony Galaitsis
> 781-862-3607
>
> ==============
>
> On 7/31/21 10:14 AM, Schonfeld wrote:
>> I want to measure how new-track starting locations are distributed 
>> around the decay source. Quantum mechanics makes a clear prediction 
>> but, remarkably, it has never been tested (to my knowledge).  Times 
>> or frame numbers are nice-to-have.  I could do without them.
>>
>> On Sat, Jul 31, 2021 at 9:54 AM Steve Isenberg <smisenberg at gmail.com 
>> <mailto:smisenberg at gmail.com>> wrote:
>>
>>     Jonathan,
>>     What are you trying to accomplish?  What is your goal, what would
>>     you do with the coordinates or frame numbers?
>>     You might be able to grab this info manually using video editing
>>     software but I don’t know a way to do it automatically. Maybe
>>     there’s an app??
>>     -steve
>>
>>     On Sat, Jul 31, 2021 at 9:46 AM Schonfeld <jschonf at gmail.com
>>     <mailto:jschonf at gmail.com>> wrote:
>>
>>         Hey wizards - Maybe someone can suggest a solution to the
>>         following question:
>>
>>         I've downloaded a YouTube video as an mp4 file.  (It's a
>>         video of tracks emanating from a small radioactive source in
>>         a cloud chamber.) From time to time I want to point and click
>>         on a feature in the video (the starting point of a new track)
>>         and have the coordinates and time (or frame number) of the
>>         click automatically written to an Excel file.  I mostly use a
>>         PC but I could easily move to a Mac or iPad.  Do you know any
>>         simple ways to do this? - Jonathan Schonfeld
>>         ===============================================
>>         ::The Lexington Computer and Technology Group Mailing List::
>>         Reply goes to sender only; Reply All to send to list.
>>         Send to the list: LCTG at lists.toku.us
>>         <mailto:LCTG at lists.toku.us>     Message archives:
>>         http://lists.toku.us/private.cgi/lctg-toku.us
>>         <http://lists.toku.us/private.cgi/lctg-toku.us>
>>         To subscribe: email lctg-subscribe at toku.us
>>         <mailto:lctg-subscribe at toku.us> To unsubscribe: email
>>         lctg-unsubscribe at toku.us <mailto:lctg-unsubscribe at toku.us>
>>         Future and Past meeting information: http://LCTG.toku.us
>>         <http://LCTG.toku.us>
>>         List information:
>>         http://lists.toku.us/listinfo.cgi/lctg-toku.us
>>         <http://lists.toku.us/listinfo.cgi/lctg-toku.us>
>>         This message was sent to s+lctglist at smistuff.com
>>         <mailto:s%2Blctglist at smistuff.com>.
>>         Set your list options:
>>         http://lists.toku.us/options.cgi/lctg-toku.us/s+lctglist@smistuff.com
>>         <http://lists.toku.us/options.cgi/lctg-toku.us/s+lctglist@smistuff.com>
>>
>>
>> ===============================================
>> ::The Lexington Computer and Technology Group Mailing List::
>> Reply goes to sender only; Reply All to send to list.
>> Send to the list:LCTG at lists.toku.us       Message archives:http://lists.toku.us/private.cgi/lctg-toku.us
>> To subscribe: emaillctg-subscribe at toku.us   To unsubscribe: emaillctg-unsubscribe at toku.us
>> Future and Past meeting information:http://LCTG.toku.us
>> List information:http://lists.toku.us/listinfo.cgi/lctg-toku.us
>> This message was sent togalaitsis at verizon.net.
>> Set your list options:http://lists.toku.us/options.cgi/lctg-toku.us/galaitsis@verizon.net
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.toku.us/pipermail/lctg-toku.us/attachments/20210803/e9a0896b/attachment.html>