I know that I can access raw video images from the iPhone's camera with AVCaptureVideoDataOutput. I also know that I can record video to a file with AVCaptureMovieFileOutput. But how can I first access the raw video images, manipulate them and then write the manipulated ones into the video file? I've already seen apps in the app store, which do this, so it must be possible.
Ok, I now know, that it's done with AVAssetWriter.
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I want to make an app for the iPhone with the ability to record video. One thing I want to do with the video once it's recorded, is to take the audio from it and alter it, such as make it sound feminine or masculine etc. I've never done this before but is it better to use AVFoundation or UIImagePickerController. I've read that the UIImagePickerController is easier to use but will it allow be to extract and edit the audio of the recorded video and put it back in?
Any help or suggestions as to how to approach this are appreciated.
Thanks
It is easiest to capture with UIImagePickerController if you do not need to alter it live. Once the video is captured and you have altered the audio track somehow, write it again using AVFoundation's AVMutableComposition and an audio mix.
I have an iOS app that I want to record some of its visual output into a video. It looks like the way to create a video on iOS is to use AVMutableComposition and feed AVAssets to it via insertTimeRange.
All the documentation and examples that I can find only add video and audio assets to an AVMutableComposition. Is there a way to add image data to it (i.e. add an image for each frame of the video)? I can get this image data as straight RGB, PNG, JPG, UIImage, or whatever is easiest to feed to AV Foundation (if it's even possible).
If it's not possible to feed images into an AVMutableComposition for the video frames, is there another way to generate an .mp4 file from frames in iOS.
To generate movies from frame you can use AVAssetWriter, here is a question that sort of covers that here on SO, question
I know how to record a video from the camera on the iPhone, my question, is it possible to take the recording and overlay it on a saved video and save it out as another file?
No, I don't think so. Not using an standard framework. You could probably do something involving screen capture and combing a load of images to make a video. But it would be complicated.
Is there a way to have my iPhone program step frame by frame through a movie recorded by the iPhone? What I want to do is have the user record a quicktime movie, then be able to step through the movie frame by frame.
Alternately, I suppose if there was a way to extract every single frame from the movie to a jpg, then I could easily step through the pictures. Anyone know of a way to do this???
I suppose the third option (which might not get past Apple's store) is to capture the movie the way the old jailbroken apps did, which is somehow capture the pictures directly from the camera view????
Any help appreciated. Thanks in advance!!!!
You cannot step through a movie frame by frame. That functionality does not exist in the public API.
You can include your own media decoder code (open source or not) and use that to parse your movies of course. It is perfectly fine to do that.
Is it possible to play audio and video file at a same time? I want to play different audio file and video file at a same time and also want control for both, so is it possible?
Sorry, not that I know of. The movie view automatically stops all audio files and takes up the whole screen, so you are forced to listen to the audio for the video.
If the audio is part of the video file, yes.
If it's an MP3 file or some other external type how are you planning on playing it? The phone might allow this to happen depending on what you're up too.
You might be in luck soon though...
Another helpful link is here.