How to encode video on the fly and send it trough the network from C#?
Can't find a suitable library. I need to encode in WMV and don't mind if the actual encoding is made in C++ as long as the library has a .NET assembly available.
Thanks
I'm aware of ffmpeg, but it is native C code only. If you're ok with interoperability this may be your ticket.
Edit: It turns out someone already wrapped this in a .NET assembly. It's called FFlib.NET.
I use the Windows Media Format SDK, although I admit I use it directly in C++ native code. I believe it can be called from managed code.
This is now included as part of the Windows SDK here:
http://msdn.microsoft.com/en-us/windows/bb190307.aspx
(or you can download it separately - see the list in the left-hand panel)
Be warned, it is a fair bit to get your head around. However, there are sample code resources which should assist.
Depending on what you are encoding (size, framerate, hardware, etc) real-time encoding may not even be possible. Video encoding is VERY CPU intensive.
Related
recently i have started workin on project of my own which is capturing a camera output using DirectShow .Net. There are few problems that i don't know how ot solve
1) How can i encode the captured stream into H.264 format.I understand i should some how add filter in the filter graph. But i wasn't able to find where and how . Also i was not able to find if there is standart H.264 filter or should i download it form some where? If i need to download it can it just be a dll to wich i add reference or should it be installer?
2) Is there a way to save the captured output into a memory object, some kind of stream or it can only be written to file?
Best Regards,
Iordan
You're can use commercial software from VisioForge or Viscomsoft.
AForge potencial problem - no audio during capture, only video. Also output formats is a very limited. But - it's free and open source, if you're have any DirectShow experiense you can add audio support.
You will need to use something like FFMpeg or Handbrake. Check out http://vidcoder.codeplex.com/.
AForge also has some video editing abilities and you can also pass filters to it. There are also several FFMpeg C# wrappers you could use such as https://github.com/crazyender/FFMPEG.net
You should use AForge.net. All of the hard work is done for you already. Use VideoFileWriter http://www.aforgenet.com/framework/docs/html/4ee1742c-44d3-b250-d6aa-90cd2d606611.htm. I appears that the AForge framework uses FFMpeg under the hood as well (See AForge.Video.FFMPEG namespace). You just create a writer and pass it the bitmap/frame writer.WriteVideoFrame(bitmap);
You should fully investigate the video abstractions in AForge. You could save yourself considerable amounts of time.
Example: http://www.aforgenet.com/framework/samples/video.html
1) Yes, You should download encoder filter library. Most of decoders are supplied with free. But encoder is not. If you don't want to pay, you have to find open source Encoder.
And To use at the graphedit program, you should do dll register with that dll file. Or the installer program do this instead. And you also need to check container type like mp4, mkv... In other words you need mux filter to save that in a file. I think someone will link available urls. Sorry I don't have urls now.
2)What is that the means of capture? Is that Movie? or Image?
In case of Image, There are many sample projects and SampleGrabbers. You can save it to both of a file and memory.
In case of Movie, I'm sure your pc memory is not enougth to them with out encoding. Make memory stream and pass it to capture manager.
You can also make a filter in order to customize filter to your needs. All of information are included in Windows SDK samples.
Just curious to see if this is possible. I have a windows application that reads all the bytes from a .avi file situated on my pc and then stores it in a byte[]. So now I have the avi file in memory, and I want to load it into some sort of a video player control, directly from memory. I've tried using the wmplayer control, apparently this is not possible. I've read suggestion about using the DirectShow and VLC plugins, but I have no idea where to even start using those two and I haven't seen any sample code of this being down. Anybody have any ideas to elaborate on the mentioned plugins, or have a different approach to it?
For DirectShow, an in-memory source filter may be required. I am not aware of such a filter being available, but one can be based on Async Filter Sample from DirectShow samples. This is in C++ though.
For .NET, DirectShow.NET library can be used. A sample GSSF filter there may be a good start for an in-memory source filter implementation. This library also provides COM Interop for DirectShow that could be used to build a test player application that instantiates this filter.
Where I can found something suitable (library) for .NET 4.0 (C#) capable for following features:
+ Reading mp3/wav samples with direct access to samplebuffer of loaded samples? (for example I want to load mp3 sample and programatically add reverb, chorus, and more custom effects implemented by me)
+ Playing directly audio buffers (arrays of floats)
+ Saving audio buffers to disk as mp3 or wav
Some time ago i found ASIO for .NET and this only works with .NET 3.5, is there something for .NET 4.0? Thank's a lot for your help.
ASIO for .NET won't help you in the cracking of mp3 or wav files. The most modern API in Windows for doing this is Microsoft Media Foundation. These are all COM APIs though, so you're either going to be doing (perhaps painful) COM interop from .NET or (easier) writing a C++/CLI wrapper. If you go the C++/CLI wrapper, you will need to be aware of performance issues (especially with how critical latency is to audio programming).
I'm skeptical that you will get the audio latency you need when programming in .NET. A good audio driver (like ASIO) will get you down to <3ms of latency. So if you are targetting "live audio", you will need to be generating audio buffers quicker than that (unless you are fine with longer latencies). To put it this way, the "time intervals" that the Windows APIs deal with are in 100 nanosecond intervals :).
You likely don't want to have to crack the files yourself. It becomes tedious as it's not only just mp3 and wav. You also have to be aware of how the wav is formatted as well (to account for different bit rates, number of channels, etc.). Using Media Foundation, it will automatically load the write decoder for you, you just give it the file path. Check out this tutorial that shows opening an existing WAV file and writing a new WAV file. I just recently went down this path for a drum sequencer I'm creating, and it's not very painful at all (if you're familiar with COM programming).
The central component in MF that makes this possible is the MFSourceReader.
If you're wanting to play the audio after you modify it, you can look at the sample "RenderExclusiveEventDriven" in the Windows SDK (under "audio" I believe). That's what I did for the drum sequencer as well. Latency won't be an issue and you're just dealing with byte arrays, so manipulating the raw data becomes very easy. Though at this point, you can probably stick with the ASIO .NET route and just use that to play the raw data you get from MFSourceReader.
I don't think there are .NET wrappers around Media Foundation yet (though if somebody has done that work already, feel free to post here as it would be awesome to know).
I want to normalize PCM WAV files from client side(Silverlight). I am using ASP.NET MVC on the server side. And I found a C program here
https://neon1.net/prog/normalizer.html
Does anyone know that if there are similar C# libraries that I can use directly?
"Normalizing" audio files is generally not a great idea, since if there is just one sample at full volume, then it will have no effect. A better approach would be to run a dynamic range compressor on the audio.
In Skype Voice Changer I have written sample code that uses NAudio and passes audio through dynamic range compressors. However, as others have said, NAudio isn't directly usable in Silverlight due to interop. But you should be able to copy WaveFileReader, WaveFormat and WaveFileWriter out and compile them without needing to make too many code changes. Also, you won't be able to use the WaveBuffer mechanism for casting between arrays of bytes and shorts/floats, so you need to do the conversion the slow way (e.g. using BitConverter).
Some ideas (aside of trying NAudio or Bass.NET)
Call the compiled c executable
Compile it as a dll and use P/Invoke
Convert the C code to c#
I would like to emulate video input from a webcam for testing purposes.
So I need to be able to emulate a software video capture device in Windows and be able to dynamically generate its output.
How can I achieve this?
I would prefer a solution in C# or C++.
You can use a Virtual Webcam (old link, but there are others) it will take a video/images file and will display it in a webcam device. Your system will think that its a normal device.
Then you will need to create something that will generate the video/images, if you need static image then its pretty easy to generate a bmp.
Old (no selected answer) question.... actually probably one of the oldest I've ever seen... but I came across this looking for an answer myself, I remembered the day when "Virtual Webcam" still existed (now just a chinese ad site).
Fear not! There are new sources to solve your decade long quest:
First of all, checkout OBS, open source does a LOT with video streams:
https://obsproject.com/
Second, checkout this virtual webcam plugin for it. Does exactly what you're talking about, and does use #qbeuek's suggestion of DirectDraw:
https://obsproject.com/forum/resources/obs-virtualcam.949/
It is written in C++, so grabbing the bits you need and rewriting to C# is left as an exercise to the reader, but the capability is there.
As far as I know, there is a set of COM interfaces that govern the recording and playback of audio and video in Windows. It used to be called DirectShow, but maybe in the meantime the name has been changed. Those interfaces are used to construct a graph of audio and video filters, to encode / decode the data stream.
The way to go:
- read about the Microsoft DirectShow API,
- implement a COM object that implements the video source interface,