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Old February 11th 04, 08:19 PM
Mark Forsthoefel
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Default Compressing an AVI File by a Moving Integration & Media Player

Astrosnap by default, integrates multiple video frames, by either
averaging or summing the frames (and subtracting a dark) (in my case they
were averaged), and then will automatically save the result as a bitmap. It
allows for an automated routine, that after a user selectable "x" number of
frames are added together, that it will automatically save the result, and
move on to the next image. Once many images are compiled (1000s), I again
took and averaged several hundred bitmaps within a specified time frame
(using too long a time frame will cause blurring due to planet rotation),
using register, and then applied wavelet processing. An entire nights (~ 3-4
hours) work can be summed into 25-30 averaged bitmaps, which then can be
assembled by Windows Movie Creator, to create a video from the averaged
bitmaps, or you could use Adobe Image Ready to create the animated gifs.
Astrosnap also has a great feature that allows a user settable sensitivity
of the quality of the frames averaged. The software automatically determines
the worst and best video frames captured, and provides a slider to let the
user determine the quality level a video frame must reach before being
applied to the stack. This basically results in a poor mans adaptive optics,
as the software waits for optimum seeing before using the video frames in
the average.
Mark
"W. Watson" wrote in message
...
Are both AstroSnap and Registax capable of doing this? In looking at

Registax it is
not at all clear how to go about this. The same is true of k3ccd if it is

capable of
this type of processing too.

Is the process for moving integration automated? It would be good to be

able to just
tell the program to sum every five images and apply a dark frame to each

while
centering each frame using the whole frame area. I'd hate to have to do

this manually
frame by frame.



Mark Forsthoefel wrote:

This is done all the time. Check out my Mars website,
http://home.woh.rr.com/frostdesign/ . Not only did I create new video

from
stacked frames, I used different formats from AVI, for smaller file

sizes. I
ended up with Windows Media Files (.wmf), because dialup accounts took
forever to download the AVIs. These WMFs are located in the individual

month
links along with the best images of the nights shoot. I took the home

page
one step further, and created animated gifs, which could be manipulated

even
further in a nice dropdown list, but at a small loss of color depth

(gifs
use only 256 colors). I'm amazed at how well these images hold up to the
original AVIs, as really not much detail was lost through the extra
compression.
Mark
"W. Watson" wrote in message
et...

With programs like registax, k3ccd, or astroregister (?), is it possible


to shoot a

few minutes of sky at say 10 frames of second in avi format, and then


stack

sequentially 5 or 10 frames intoa new image, then stack the next 5 or 10


frames into

a second image, etc. so the resulting stacked images are in a avi file?


For example,

if my avi has file has 100 images, can I automatically sum each
successive group of 5 into a new image to produce a new file with 20


images?

The end result of this process should be a shorter movie with individual


images

created from successive sections of the original.

This reminds me to ask the following question. I'm creating a sky image

at

4 avi

frames per second, and, when I playback the avi file, it plays back in

MS

Media

Player as slowly as it was created. Is there a way to speed the playback


up to 15 or

30 frames a second?

--
Wayne T. Watson (121.015 Deg. W, 39.262 Deg. N, 2,701 feet,

Nevada

City, CA)

-- GMT-8 hr std. time, RJ Rcvr 39° 8' 0" N, 121°

1'

0" W

"Don't you just hate it when someone leaves their call back

phone
number at 100 digits a second? And worse. At the end of a long


message."

-- Andy Rooney (in disguise)

Web Page: home.earthlink.net/~mtnviews
sierra_mtnview -at- earthlink -dot- net
Imaginarium Museum:


home.earthlink.net/~mtnviews/imaginarium.html




--
Wayne T. Watson (121.015 Deg. W, 39.262 Deg. N, 2,701 feet, Nevada

City, CA)
-- GMT-8 hr std. time, RJ Rcvr 39° 8' 0" N, 121° 1'

0" W

"Don't you just hate it when someone leaves their call back phone
number at 100 digits a second? And worse. At the end of a long

message."
-- Andy Rooney (in disguise)

Web Page: home.earthlink.net/~mtnviews
sierra_mtnview -at- earthlink -dot- net
Imaginarium Museum:

home.earthlink.net/~mtnviews/imaginarium.html