Re: screen capture, using SoftVDigX
Re: screen capture, using SoftVDigX
- Subject: Re: screen capture, using SoftVDigX
- From: John Robinson <email@hidden>
- Date: Fri, 21 May 2004 15:44:30 -0400
Thanks again Douglas,
These products look pretty good. I couldn't find the plugin on the
ZyGoDigital site though. I'd also prefer to do it myself, since a) I'll
be learning something new, and b) it won't cost me anything aside from
time :).
A little more info...
My 'real' work is centered around flash applications, and more
specifically, flash and flash communication server applications. To
those unfamiliar with the latter, the flashcom. server is a real-time
media server that works in conjuction with the macromedia flash player.
The player is able to access local cameras, and stream their video to
the server, which in turn can stream them to other users. So in it's
most basic form, what I want to create is a soft-cam that broadcasts
the user's screen as a video stream. Once the kext is loaded for
SoftVDigX, the output shows up in the flash player beautifully as a
video source. In essence, I feel like I'm 80% there already.
Ideally, I'd like to build a cocoa application with one main window
with a semi-transparent box that could be resized. The screen area
beneath this box would be the video source. So being a complete
newbile, I'm stuck as to how to take this c++ sample code, and either
modify it to do what I want, and tie it into a cocoa app, or at the
very least, modify it to do what I need. I think the links to the
sample code should get me started, but does anyone have any tutorial
links, or suggested reading as to how to integrate this c++ code into a
cocoa application?
John
On Friday, May 21, 2004, at 03:23 PM, Douglas A. Welton wrote:
Hi John,
Have you checked out Snapz Pro X from Ambrosia Software? If not,
check out
the following link:
http://www.ambrosiasw.com/utilities/snapzprox/
You may also want to check with the folks at ZyGoDigital.com, they
have a
QuickTime Component that will webcast screen captures.
Timbuktu also provides a similar functionality:
http://www.netopia.com/software/products/tb2/mac/
If you are interested in how to do a screen capture, I would suggest
that
you check out Josh Anon's example of how to do this with Cocoa and
Quartz:
http://cs.nwu.edu/~josha/ScreenCapture.dmg
Josh's code can probably be modified with an NSTimer to periodically
gather
screen captures. You could then turn the resulting NSImage objects
into a
movie or heave them over the network using TCP or Rendezvous.
If you haven't read the doc on Quartz Services, I'd suggest that you
check
it out.
You may also want to check out the "old way" of doing screen captures.
Apple has two projects in the Legacy Sample Code library, Snapshot and
SuperSnapShot. Although they are "legacy code" and supposedly no
longer the
way to do this, I think that they have a lot of value to add to your
quest.
You may also want to check out Apple's mailing list archives for
quicktime-api and quicktime-talk. Both archives have a number of
threads
relating to what you are wanting to do.
hope that helps...
later,
douglas
PS: As for list etiquette, I usually keep most of my replies on the
list
for archival purposes. Several times, people have reference my post
from
"years ago" when bringing up a new topic... and on many occasions, I
have
found the answer I needed by reading a completely-on-the-list old
thread.
on 5/21/04 2:31 AM, John Robinson at email@hidden wrote:
Douglas,
Thanks for the response. I'd like to continually grab the screen, and
hopefully eventually (and optionally) just a portion of the screen so
it can be viewed as a video stream elsewhere. You could then use it
with iChat or Yahoo messenger to show someone else your screen. From a
tech-support point of view, you could use it to view their screen,
without the intrusive feelings of say, remote-desktop or vnc. There is
a windows program that does the same thing called Camtasia though I've
never actually used it.
Finally, I'm new to this list, and don't really know the etiquette..
is
it standard-practice to copy the list on every message? I'm used to
lists that just reply to the list by default.
Thanks!
John
On Thursday, May 20, 2004, at 11:52 PM, Douglas A. Welton wrote:
John,
I may be able to help you if you can give me a little more
explanation
of
what you're want to do. Why do you want to capture the screen? Why
do you
want to feed the resulting image into a faux input device (especially
when
you could just save the series of images as a QuickTime movie without
needing to do a Sequence Grab)?
later,
douglas
on 5/20/04 5:31 PM, John Robinson at email@hidden wrote:
Hello all!
I had been searching for a way to do this for quite some time, with
0
success. I'm new to cocoa and c++, but have slowly been getting to
terms with Cocoa. After seeing the post from Douglas Welton pointing
out SoftVDigX, I screamed with joy, since this is exactly what I've
been looking for.
Now, my problem. How can I modify this sample code to first grab a
screenshot, and then use that screenshot instead of the included
image
data? I've narrowed it down to these lines (I think) in the file
"SoftVDigKEXT.cpp":
line #92
fFrameSize = sizeOf(frame_00);
and then in SoftVDigKEXT.cpp:
line #258
memcpy( fMemBuf, frame[fFrameCounter++ % NUM_FRAMES], fFrameSize );
I can see how/where it's using the hardcoded array of frame data,
but
I'm clueless how to replace that with a screen-capture image. Any
ideas?
Huge thanks in advance!
John
_______________________________________________
cocoa-dev mailing list | email@hidden
Help/Unsubscribe/Archives:
http://www.lists.apple.com/mailman/listinfo/cocoa-dev
Do not post admin requests to the list. They will be ignored.