I can find plenty of methods for extracting all frames of a video when it is not playing. However what I want to achieve is extracting frames at runtime while the video plays. I want to be able to scan the video for qrcodes at runtime, but my blocker is extracting the frames while the video plays.
My platform for building this in is Windows and C#.
Looking for any library or strategy to achieve this. The best idea I have so far is have the video playing and extract and scan frames for each N second that the player progress hits. But there must be something better than that.
Maybe this tutorial made by Microsoft can help you a little bit.
https://msdn.microsoft.com/en-us/windows/uwp/audio-video-camera/get-a-preview-frame
Hope that my answer was helpful for you! :)
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My goal here is to be able to play an MP3 in an OpenTK/OpenGL application (.NET but NOT windows forms), being able to stop/play/pause it, access/set the position of the audio file, and have it play to within a few milliseconds of when I tell it to.
I've tried using WindowsMediaPlayer (WMPLib) but for whatever reason the audio doesn't start playing until I resize or move the window. Not sure why but it probably has something to do with the fact that it's meant to be a control on Windows Forms, and this is a GL application.
I've tried using .NET's soundplayer but that incurs a huge delay of up to a second, and I can't set/access the position of the file.
I've looked into OpenTK and OpenAL but that seems way too complex to figure out.
Does anyone have any ideas?
THANKS!
Oh and worst case scenario I could also deal with playing WAV or OGG files instead, and if the play timing is accurate enough I wouldn't need access to the position of the audio.
OpenAL may seem complicated, but it sounds like the best solution to your problem. There's plenty out there on it, though most examples might be in other languages, but the API is the same. Perhaps this thread has some solutions as well.
I am developing a game for Windows in C# using Visual Studio 2010 and XNA 4.0. I would like to be able to set and change the play position of an HD video and also play the video in reverse, depending on user input.
I am having trouble finding where to start. XNA's videoPlayer class does not provide these type of functions. I've read that XNA DirectShow is now out of date and slow when using HD video.
I don't quite understand how I would be able to use or implement tools such as ffmpeg with my project. It seems some people have had similar questions and posted solutions but without much detail. These are below.
interop out to talk to the core DX functionality.
write a managed c++ wrapper to interop ffmpeg.
write an mpeg decoder.
I am not sure what would be best and where to begin.
Thanks!
The VideoPlayer class has a "PlayPosition" property, which you should be able to play with.
Otherwise (and I don't know how big your video file is nor how long) try an image sequence and animate the current image sequence and control that with user input. Of course working with image sequences would make audio reversal (if there is audio) etc very complicated.
Last but not least, you can see if you can figure anything out from this mpeg decoder here:
https://www.box.com/shared/ojzfv0qzfx
Something else that might help with mpeg decoding:
http://chrisa.wordpress.com/2007/11/21/decoding-mpeg2-information/
I want to be able to precisely control the timing of .wav files played in my program. I also want to be able to play more than one .wav file at the same time. The SoundPlayer was not good enough because I can't play two sounds at once, and even when I play different sounds consecutively, there is about a 1/8th second delay between each sound, which is unacceptable for what I am doing. I cannot find a way to add a Device using SharpDX.
You have a directsound sample in sharpdx, should get you started.
Also you can have a look at NAudio , which should also fit your needs and be a bit easier to use.
I've spent days googling and coding tryin to acheive the basic level of effect all media players have when showing fancy subtitles - that being text (optionally with outline/dropshadow/glow) written above a video (video being a videofile but would nice to also have option of being a videofeed eg webcam).
So far the only way I've managed to get anything over a video is either to write to a transparent picturebox above a video component which is aliased so has dodgy outline, or using the directshow.net library and the capture method from the dxtext example I have managed to actually write over a picturebox that is being spat frames of the video. The problem here is that as soona s I add the writing commands in (video plays to picturebox fine without it) then I get slight fps hit coming accross as marginal stuttering on the video.
Does noone have a way to just write/draw over a video without taking this kind of performance hit? Or am I going to have to resort to directx or something or just give up on this luxury? :/ I can paste any code needed for help but I think anyone with assistance will probably be the one wanting to post code!
TIA for any input, it's doing my head in D:
I am new to DirectShow.
My intention was to develope a small application (C#) that handles video processing.
The main tasks i need are :
1 - Display video content from a DVD.
2 - Navigate to specific points of time in the video.
3 - Capture specific frames into still images and save them to files.
Sounded easy at first, but after reading thousands of blogs, forums and code samples i can't figure out how this can be done .
I am pretty sure these tasks have been implemented plenty of times, so if anyone has anything that can help i would be very happy to hear it.
As i am getting desperate on this issue, buying external DLLs or paying for some advice is an option.
Thanks.
Not sure if this will help, but I have a DvdPlayerElement control in my WPF MediaKit.
You must install an audio codec if you want audio as the built in one with Windows is locked down due to licensing.
perhaps you can wrap the MSVidWebDVD object, combined with some screen capture techniques [?] see also Extract frame from VOB(DVD) file
Thanks Jeremiah, I do know WPF MediaKit and tried working with it.
It is pretty cool, but does not allow all of the functionality available in DirectShow.
There are some events missing and the seeking operation does not seem to work for me.
I guess i can dig in the code and figure it out, but the time pressure won't allow it.
If you have an example of an application that accomplishes what i am looking for (display, seek, capture) i would be very happy to take a look.
Thanks again.