Office Hours — Today, April 21

Thursday, April 15

Apr 21
6:25 PM
Mark M.
has entered the room
Mark M.
turned on guest access
6:30 PM
Scott
has entered the room
Mark M.
howdy, Scott!
Scott
Hi Mark
I've got some questions for you regarding MediaRecorder
Mark M.
haven't used that yet
so, my knowledge is limited
Scott
Ah, ok
Mark M.
but I'll try!
Scott
Well I've found some limitiations that I've been trying to overcome.
Basically, I'm trying to use it to record video continuously, but save to multiple small output files.
I can set the output file name through the provided method, and start and stop the recording fine.
The only way I can change the output file though seems to require that I reset the MediaRecorder object and go through the prepare process again
6:35 PM
Scott
This ends up with too large of a gap between files.
Mark M.
that's not surprising
Scott
There is a onPreviewFrame callback that supplies raw data, but it is too expensive to handle managing the raw data through that and writing to a file.
Also, two concurrent MediaRecorder object do not work.
Thought you may have some advice how to achieve this.
Mark M.
I haven't quite figured out how Qik and the others do live video
Best guess is that they use the FileDescriptor version of setOutputFile and handle chunking themselves
but, I'm not enough of a MP4 guy to know what that would entail in terms of having workable files in the end
Scott
Yeah, I've thought about that as well but haven't tried to implement.
would require inserting a video header to each file I try to create
Mark M.
something like that, yes
6:40 PM
Scott
Do you know anything about the opencore libs like pvauthor?
Mark M.
nope
nary a clue
Scott
hmm, ok. It seems those lower level libs that MediaRecorder is built on have methods that could close the stream and change output file without re-initing
I haven't done any C++ for Android though
Mark M.
that's on my todo list for next month
Scott
working with the video capture?
Mark M.
no, NDK
Scott
ah, ok
well, thanks -- I guess I'll try to implement the other method first.
Mark M.
sorry I wasn't of more help
6:45 PM
Scott
No problem -- thanks!
6:45 PM
Scott
Be back soon I'm sure :)
7:00 PM
Scott
has left the room
7:25 PM
Mark M.
turned off guest access

Thursday, April 15

 

Office Hours

People in this transcript

  • Mark Murphy
  • Scott