In my app I want to give effect to audio and video file like it is given to Pheed Application. I want to mix audio recorded sound with predefine clips. And also want to give sound different effect like echo , surrounding Normal , And with video file I want to add different effects like sepia,.. I don't know which class library I have to use to implement6 this . Can any one suggest me any library for that or any way how to do that?
Here are a pair of libraries you can try:
For audio filters and effects you can try with The Amazing Audio Engine. It is build on top of Core Audio.
For video effects try GPUImage. I haven't tried it but it is supposed to work better than Core Image when handling videos.
Related
is it possible to have a real-time preview of AVMutableComposition which has some layer instructions applied to its assets?
The only class I found that connects AVMutableComposition with AVVideoComposition (holding instructions) is AVExportSession. Does it mean I must export it first to play a preview?
If so, how does apps like Final Cut Pro serve real-time preview when I edit part of the video. Do they cut the whole video into multiple chunks, export what has changed and keep change of everything else?
This sounds like a difficult problem - is there any library that would help in cutting video into small chunks to export and keeping an eye on cache invalidation?
Cheers,
M.
I don't know if this is still relevant but you can always extract each frame from the video, manipulate it accordingly then render it to the screen.
If its from AVCaptureSession you can get CMSampleBuffer from the callbacks, if it's a file I think AVReader is your best bet then you can use either CoreImage or Metal to manipulate the frames and render them in real-time.
There is no real time preview with AVMutableComposition , they may create a time slot for every change and manage it's visibility when you change the slider below
What's the common modern standard for animated video overlays? (e.g. if you want to add an animated logo to video recorded from the camera)
During research, I've found the following options:
GIF - seems to be pretty outdated technology
FLV - supports alpha-channel, but no longer supported by Adobe.
Requires FFMPEG.
PNG sequence - the downside of this is having multiple files for each
frame.
What's the right format/technology to use?
Ideally, what is natively supported on iOS (doesn't require FFMPEG)?
If you want to overlay your custom video animation over video which user will be recorded I suggest to use GPUImage framework which allow a lot video/photo customization's and different graphic effects. For example how to mix two videos: nice article. Also I suggest you to read article about Chroma key which are something like standard of video/photo mixing. (because as I understand you just want make something like watermark?). GPUImage also has Chroma key filter which you can use in your purpose.
By default Apple supports h264 codec in mp4 container. So your video should be in this codec.
Hope I fully answered on your question
The best way to add overlays using the AVFoundation framework supplied by apple itself. Speaking about the other ways such as GIF, FLV, they are not supported natively by APPLE which puts you out of luck.
Apple suggests various tools such as AVVideoCompositionCoreAnimationTool that lets you stitch the Core Animations and the videos together.
Here is a link that explains how to add various effects such as
Colored borders with custom sizes.
Multiple overlays.
Text for subtitles or captions.
Tilt effects.
Twinkle, rotate, and fade animation effects!
I am not sure how much of this is application for the application that wanted to add animations while recording. May be some one else could help in it. I hope this helps you about the native way to add animations in recorded videos in iOS.
I'm using AVMutableComposition and AVAssetExportSession to composite several discrete audio clips/files together into a single file, similarly to this post but there will be no "video" track. I'd like to give the track some visual appeal using a still image so that when the user plays the clip they don't just see a generic quicktime icon, ideally I'd replace the image with branding or something relevant to the audio content. How would I go about doing it and is there a way to do it without dramatically increasing file size(ie some way to have a really slow framerate or just something so its not generating 30 fps for what is non moving art.) Appreciate any help on this.
AVAssetWriter will allow you to create video from a still image. This question provides a great example of how to do so.
I'm currently working on an augmented reality app, that's why I would like to add an image above the live video feed (GPUImageVideoCamera) AND be able to record the whole to an output file.
Get the video live preview, and recording is ok from now, but I can't manage to add the image on the screen the way it's recorded to the output file.
What's the best way to achieve this (I mean a GPUImage compliant way) ?
I want to play four videos on the same view within a small rectangular area, is that possible ?
I think you can do this with AVPlayer and using AVMutableComposition.
With AVMutableComposition you can combine multiple sources into one combined playback source - I'm currently working on an Application where i use this to combine different audio and video sources and play it back as a single track even though they come from seperate files.