Is it possible to simultaneously playback the recording device by using the FMOD api? This functionality would be the same to what Windows offers in the recording device properties where you can enable "listen to this device" for certain recording devices. If this isn't possible via FMOD, is there another API more suited for this functionality?
You can achieve this with FMOD by simply recording with looping set to true, then play the recorded sound as looping also. Providing you separate your recordStart call and your playSound call by some time (say 10ms) the play cursor and the record cursor will follow each other and you will get realtime playback.
There is an example of this with the "recording" example that ships in the FMOD API for most platforms and there is a more advanced example on the Windows platform that shows adding realtime effects to a live recorded sound.
Related
I'd like to know what API from their reference manual to use when I would like to save the recorded video on the SD card with Mavic 2 Pro. I believe that one cannot save video directly on the computer without perhaps using DJI Assistant 2 or so? In their manual (51169 p. 32) for the drone it says that regarding the flight recorder "other parameters" will be automatically saved to the drone's internal data recorder. This internal data recorder, is it referred to its micro SD card? If so, will all default recordings be automatically saved to that SD card? And if still so, is there a way to retrieve these video files via the computer in the code or only through DJI Assistant 2?
My intention is to do something with this video via the computer at the same time running the software I am working on developing (application) in Visual Studio, not to use several different applications. In normal use case scenario as described above, by, I believe, default procedure, would be to record the video, and have it accessed through the Assistant 2 app, and copy that video file over to the application I am working on, and from there present some options to the user with the video, like replay it faster.
Every time I'm working on a Core Audio application, specifically one that utilizes real-time audio via the remoteIO audio unit render callbacks, the moment I start the audio unit engine running whatever music I am playing via youtube or itunes is muted. I must reload the youtube page or reset my system preference audio settings to get sound back. Is there a solution to this?
Set the mix-with-others property on the Simulator's RemoteIO Audio Unit before starting it. Also enable a proper AVAudioSession category.
Can we use the Expensify Frame work to test Voice Commands on Emulator/Device..
The feels like this should be possible, but isn't something that I've already coded.
To achieve it, you'd have to setup some sort of playback system to create the audio voice commands. This could be done, for example, by using audio playback triggered from C# SpecFlow steps on the PC - e.g. using something like DirectShow/quartz - http://csharp-slackers.blogspot.co.uk/2008/10/playing-wav-or-mp3.html
This audio would then be played out and captured back into the emulator through the speakers and microphone on the host PC - just make sure they are positioned appropriately.
i am looking for differnt solutions to capture video stream from monitor screen and send it to vidoestreaming server to broadcast in web. it must occuring in "live".
i'd not like to use external services like "procaster" for broad.
OS: Windows.
it will be great to know the ideas and expirience people have to accomplish that.
Thanks all.
Recently, I build a GoLang project called ScreenStreamer, is a tool to stream current active window or full screen (Linux's or Windows's) to other device, like phone or another PC, as MJPEG over http or FLV over rtmp, it's very realtime (delay < 100ms). It works on Windows and Linux.
After building it, you can run it as:
# enter the project root directory
cd ./src/ScreenStreamer
# run it
./mjpeg or .\mjpeg.exe
# use a web browser or other video player, open http://host:port/mjpeg
./rtmp or .\rtmp.exe
# use a video player, open rtmp://host:port/live/screen
Screenshot:
Windows SDK includes Push Source Filters Sample, which in turn contains CPushSourceDesktop filter/class.
CPushSourceDesktop: Copy of current desktop image (GDI only)
It captures desktop image and pushes it into DirectShow pipeline. From there on you can process it using video compression codec and stream it to remote location. A decent screen image compression codec is included with Windows Media subsystem, network streaming will have to be a custom or third party component. Alternatively, it is possible to make the capture class a virtual camera and have Windows Media Encoder broadcast it (or, it already has a simila feature built in).
Alternatively, you can check VNC (or one of the clones) source code and see how it hooks windows and captures image updates, then compresses them and makes it available for remote applications.
Note that you will have to specifically capture non-GDI images (such as coming from video/gaming applications, which use hardware acceleration and non-RGB surffaces).
I'm looking for writing virtual camera drivers. Does anybody has idea?
Any book that would be helpful or any link.
Adding more details:
I have developed a device driver which saves the image to disk and the display uses the device driver to display the image. The performance does not seem good.
The fns. that I have used are:
//to capture
GetDesktopWindow()
CreateCompatibleBitmap()
Save()
//to display
WM_MOUSEMOVE
giving a call to capture and display every time
but the display is not continuous and appears only after window goes out of focus and comes in focus again
Should I use some other technique to record or display images, what will give fruitful results, please help.
Thanks,
-mitesh
What do you mean by virtual camera driver?
It is possible to write a virtual capture device using DirectShow. Such a virtual capture device can then be used by applications such as skype, etc. If that suffices for your needs, you can download vcam from http://tmhare.mvps.org/downloads.htm under the "Capture Source Filter" link.
Edit:
In order to use that capture device in the link I posted you need to download the Windows SDK. The Windows SDK has a tool called "GraphEdit" If you search online, I'm sure you can find a quick GraphEdit tutorial. Basically GraphEdit allows you to construct a multimedia pipeline by connecting a bunch of filters. (This is what happens in the background for instance when you play a movie on your computer. ) This could be something like
web cam -> renderer
or
file source -> some decoder -> renderer
and would result in you seeing the video captured by the web cam or the content of the file. The example download shows how you can construct a virtual capture device i.e. it looks like media is coming from a 'real' capture device, but actually you can generate any video you want if you adapt the code to your specific means i.e. take a screengrab and output that. Applications like skype can pick up you virtual capture device if it is registered correctly.
The easiest way to find out if this is sufficient for your needs is to download the capture source filter, register it with the regsvr32 command, and then to use GraphEdit to insert the capture source into a graph, connect the source to a video renderer and hit the play button. A lot of the above mentioned concepts/keywords might seem new to you, but you can do some reading on each topic, and perhaps this will give you a point to get started.
Edit 2:
Is the capture source filter approach not sufficient for your requirements?
1) AFAIR you stated in your (now deleted) answer that you would like to take a screen grab, and use that as a virtual camera device for use in applications such as skype.
If that is all you require, you do NOT have to write a device driver. DirectShow can do that perfectly well by means of the capture source filter. You would then need to
learn some basic DirectShow
modify the source code of the capture filter to take screen grabs etc.
As far as books are concerned to write device driver to accomplish the same, I have no idea. The point I'm trying to make, is that you need to determine whether you actually need to write a device driver or whether simply modifying the open source capture filter is sufficient.