I'm muting volume in QTkit like this:
if
([muteButton state] == NSOnState){
[mMovieVolumeSlider setFloatValue:0.1];
[testMovie setVolume:0.1];
The problem is the volume attenuation is sudden and abrupt. How can I implement a fade effect to the volume attenuation?
Also - my app runs .pls audio stream files. I have the .pls files embedded in the bundle. When selecting a stream within the app, a short delay is common before the stream begins to play. I want to display some sort of status message ("Buffering" or Connecting") during this short delay prior to connecting. When the stream begins the status message would end. Any idea's on how to approach this?
thanks for the help.
-paul.
I'll just outline my answers to your two questions as suggestions:
What you want to accomplish sounds much like a good fit for NSAnimation (either through subclassing or delegation — animation:valueForProgress: will probably be your friend here).
Open the QTMovie asynchronously and listen for the QTMovieLoadStateDidChangeNotification.
HTH
Daniel
Related
I would like to make a a software setup that would let the user switch between two webcam feeds (or more but let's consider two). I would like a fade in/out effect while switching. My main problem is that I don't know how to start.
There seems to be some ffmpeg tool that could do the job (like libavfilter) but I don't get how I could setup it.
What should I consider to use if I want to access frame image to make the transition myself? Is there some simpler way?
I know that this question looks really poorly written, but I'm as lost as I look.
i'm new to windows phone 8 and need your help to capture screen activities in a video. I've to make a video of the activities performing on screen?
one solution to this that strike in me is to capture the screen in image form by dispatching a timer at a instance of time but this is not a right way to do as i've to make a video of screen activities? suggest your opinion how to handle this problem.
There's no built in way of doing what you want.
You will need two things:
Do a dispatch timer as you describe
Find code that will encode these frames into a movie. That's not an API that the phone supports - you will need to find existing code and use it. I am not aware of such code existing, but I have only looked for it once or twice and not very hard. You could, potentially, create an MJPG which is a fairly simple video format, but even that's not trivial and the ending file size can be prohibitive.
We are developing a music player app for Lion OSX(10.7), which applies different audio effects to selected music file.
We have used Audio unit and AUGraph APi's to achieve this.
However after connecting all the audio unit node , when we call AUGraphStart(mGraph) graph takes around 1 sec to invoke first I/o callback.
Because of this there is slight delay in the beginning of the playback.
How can we avoid this delay?Could any one provide any imputs to help us solve this issue?
One solution is to start the audio graph running before displaying any UI that the user could use to start playback. Since the audio units will then be running, you could fill any audio output buffers with silence before the appropriate UI event. If the buffers are small/short, the latency from any UI event till an output buffer is filled may be small enough to be below normal human perception.
I have a custom UISlider and use the currentPlaybackTime to change values of an MPMoviePlayerController object.
The problem is when i scrub at a fast rate using the slider, it doesn't respond as fast as i would like..
Is there any better way to have a fast interactive scrubber for ipad? targeting from OS 3.2
Well there are two issues, only one you can control directly.
Multimedia-content is commonly compressed using some kind of delta-compression, hence quick and exact seeking is not a trivial task to cope with. As that is common and since you can not directly change that, you will have to live with it.
the only way to increase responsiveness for seeking on the content-side (when encoding) is reducing the gop-size - that is, less p-frames between the i-frames.
when using a slider or a similar control, you could, instead of directly connecting the current playback position with it, handle any manual changes in an indirect fashion. You could run a timer based job that, whenever the slider/scrubber has been moved, tries to adjust the playback position towards that new value. Once the player is seeking, prevent the scrubber from getting feedback from the current playback location but allow it once the player is in playing state again. That way the user does not directly experience the clunky seek feedback.
I want to make a simple assistant for putting together AviSynth scripts. This would be a windows desktop application that would have a "preview" screen of an avi movie, which would give you a timeline, play, fast-forward, rewind, advance and go back frame-by-frame. The program would need to know the frame number of the current frame in the player and its filename.
What language is best suited for this? I know PHP ( I understand that this is not a contender ) and am familiar with Java. My thought is that the biggest hurdle with this project will be finding a library for the video playing features. With a cursory glance, no Java video libraries jumped out at me. My next thought would be c++ for this.
The output of this program would be an AviSynth script, a plaintext file which looks like this:
AviSource("myAvi.avi")
Crop(0, 0, 320, 240)
Blur(0.1)
There are a few tool kits that can do tihs:
C#: DirectShow (DirectX)
Java: JMF
If you have Avisynth installed, the only thing you need for preview (If I understood, that's your need) is something that can decode uncompressed video. It would open like a normal file. I'm sure there are video players implemented fairly well in Java, but I don't know how much functionallity from them you need. Anyway parsing scripts is not easy - I recommend you not to try to if you don't need to.
EDIT: I'm sorry, I thought you needed a very specific app, but from what you seem to need, you don't need to code anything, use AVSP!
Please watch this video, it shows how straightforward it is. It has advanced functions such as auto-completion, (even from your own auto-loading scripts!) syntax coloring, macros, automtic importing, drag&drop (of a video, for instance - just drag it to the video and AVSP makes the loading) scrit preview with zoom and all stuff, you can use automatic or custom sliders (you can make a slider that re-writes a number on the script in real time, for instance for hue/luminosity/contrast/etc. that would be cumbersome to control via script), checkboxes & radio buttons (for boolean values, etc...), text fields that alter strings in real time, and basically anything you need... Please check it out.
Also, VirtualDubMod is OLD.
And yep, AVSP is free, both gratis and libre! =)