Does iChat support JPEG video streaming

Question

Dear Sir,
I would like to capture image and then encode to JPEG format and then send the JPEG file to iChat 15 times per second. Does iChat can display the JPEG file properly?
Thanks!
Best Regards,
sunshine_uyl

Answer 1

Ok,
Some more backing up and standing back from this.
I am still trying to interpret what it is exactly you are wishing to do.
If this "board" is something you want to use as a Camera source and it supplies or rather can supply stills of one form or another at 15fps then I don't think this is going to possible.
As one source iChat can use DV format in it's plainest form. (NOT DV or any proprietary versions)
As another iChat can since OS X 10.4.9 use the UVC driver to access USB 2.0 UVC compliant cameras
iChat has some support folders in the /System/Library and the Frameworks and PrivateFrameworks.
These control which video feeds it allows in a sort of "Native" form if you like.
This is through the CVPixelBuffer and the CVOpenGLBuffer (CV = Constant Video)
At least for iChat 4 in Leopard - I am having difficulty in working out where they have moved things in iChat 5/Snow Leopard)
Certain USB 1.1 Cameras that have Mac Drivers Installed on the Mac still need a third Party utility (iUSBCam) to convert the video from that camera into something iChat can use.
Mostly these were VGA output (See Here http://en.wikipedia.org/wiki/Webcam#Technology)
Certain IM apps such as Yahoo for Mac use a web cam but provide a collection of rapid Stills much like you talk about to give the appearance of movement.
There are certain apps that can do the same and Stream those as a Live feed to a web site. See Evocam or Security Spy
On the other hand can iChat deal with jpegs or in fact any Still format the answer is yes.
In iChat 4 and higher there is iChat Theatre and iPhoto Share.
iPhoto Share can play a Slide Show of anything in a collection/Slide show that has been set up in iPhoto (best to turn Music Off in my book).
As this could be a folder within iPhoto I toyed with the idea of getting new pics into iPhoto fast enough to display in s Slide show but have not checked what the fastest display a Slide show can manage but doubt it is 15 a sec.
iChat Theatre can be used to display the docs from other apps
For Instance it can play Movies. If you have Quicktime Add-on plug-ins to display a movie on your Mac than it can play almost anything. (Perian can play Dvix for instance along with others and Flip4Mac can play .avi files and other Windows formats).
It can also display the slides for Powerpoint or Keynote (Pays to change the Side Ratio to 4:3 or better still Square to fit the Chat Video Chat window).
I must admit to not having tried that many other apps but the same should apply in a lot of cases.
In both case your Video feed is replaced with a "Stream" of the App or file in question.
Next.
iChat can also do Backdrops in Video Chats on Intel macs.
The Backdrop can be a single Still or a Movie (you are asked to step out of the Frame so it can register the background where you sit and then replaces that with the Movie or Pic). You don't have to step back into view and it could then "Stream" that pic.
These are created by Quartz files splitting the Cameras Feed off from the background and adding either Filters for the Effects or Adding Pics or Movies for Backdrops.
These files are created with Quartz Composer (Installed with Developers Tools on Your Install Disk > Optional Installs).
Whether Quartz Composer can be made to "See" the Input from the "board" I am not sure. (Image seems to be one Still Only and Video seems to be the Camera (I did not spend long looking at how the controls/source might be tweaked).
Thirdly.
I was discussing this with EZ Jim, a level 4 poster who hangs out mostly in the iSight Forum.
He was wondering if you meant getting the board to Chat with iChat like it was a Buddy (and then presumingly recording the Video chat, to get around the USB input constraint.
If the board was Internet able and could Interact with either a Jabber Server or the AIM Servers (run an AIM or Jabber client that was Video Capable) it would have to send data in the H264 Video format.
I don't think this is what you meant but I thought I would pose it for clarification.
Another possibility is a DV converter as a Standalone items between the board and the Mac.
I had one that had RCA, S-Video and Firewire inputs.
This would be an expensive option and depend on what outputs the board has physically
Summary.
Board as camera I don't think is likely unless it can produce DV Video
My 8 1/2 year old G4/1Ghz Dual Processor (Mirrored Door Tower) can handle an USB 2.0 UVC complaint camera.
It has handled DV input from a DV converter in the past.
It basically depends on the Pic size in this case (Aim for 640 X 480 pixels as a Max)
Boards as Means to Input a feed like other apps for iChat Theatre would depend somewhat on the working space or Doc that was created.
I would have to play around with a few more to find out what the limitation were.
(At this point I would imagine using a single file that was being updated 15 time a sec but have difficulty thinking that many processors would cope with that let alone access it at the same time as another app was updating it.)
I have a feeling iPhoto can not play a Slide Show with each pic being only 4 secs "long". It may also not cope with a folder that was having more pics added to it (Can't add Photos to Slide show on the fly as it were)
I do feel the Quartz Composer route may have merit.
Quartz Composer does allow Input from several sources an may be able to "see" the board directly over USB rather then importing a file.
In may well be able to Input a series of files which would mean the board having an App on the computer to save the files to then read.
This would require learning some new skills and take a while to set up.
Although getting Pic into iChat and sending them to 1 person in a video chat would inherently be more secure there may be other ways of getting a series of Pic as "video" feed on to a web page or other Broadcast method.
See EZ Jim's list http://www.ralphjohns.co.uk/EZJim/EZJimpage7.html in the top left hand section and Nannycam at the bottom.
If the Board can Export in Streaming Flash then also see the items 9 through 12 in this section http://www.ralphjohns.co.uk/page5.html#_othe
I may receive some form of compensation, financial or otherwise, from my recommendation or link.
Essentially I don't think there is an Easy Way to do this.
11:01 PM Thursday; August 19, 2010
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