Are there any easy solutions for saving a number of images into a video file in iOS?
Example: I have 300 frames all saved as separate images and want to turn them into a single video file (e.g., mp4) that a user could email or post on YouTube.
No support in iOS, you may have to use open source libraries such as ffmpeg.
Related
I want to play the video simultaneously while it is downloading via unitywebrequest. Will AVPro video support this? If so please provide me some guidance, as i am new to unity and avpro video. I can able to play the video which is downloaded fully through FullscreenVideo.prefab in AVPro demo. Any help will be much appreciated.
There are two main options you could use for displaying the video while it is still downloading.
Through livestream
You can stream a video to AVPro video using the "absolute path or URL" option on the media player component, then linking this to a stream in rtsp, MPEG-DASH, HLS, or HTTP progressive streaming format. Depending on what platforms you will be targeting some of these options will work better than others
A table of which file format supports what platform can be found in the AVProVideo Usermanual that is included with AVProVideo from page 12 and onwards.
If you want to use streaming you also need to set the "internet access" option to "required" in the player settings, as a video cannot stream without internet access.
A video that is being streamed will automatically start/resume playing when enough video is buffered.
This does however require a constant internet connection which may not be ideal if you're targeting mobile devices, or unnecessary if you're planning to play videos in a loop.
HLS m3u8
HTTP Live Streaming (HLS) works by cutting the overall stream into shorter, manageable hunks of data. These chunks will then get downloaded in sequence regardless of how long the stream is. m3u8 is a file format that works with playlists that keeps information on the location of multiple media files instead of an entire video, this can then be fed into a HLS player that will play the small media files in sequence as dictated in the m3u8 file.
using this method is usefull if you're planning to play smaller videos on repeat as the user will only have to download each chunk of the video once, which you can then store for later use.
You can also make these chunks of video as long or short as you want, and set a buffer of how many chunks you want to have pre-loaded. if for example you set the chunk size to 5 seconds, with a buffer of 5 videos the only loading time you'll have is when loading the first 25 seconds of the video. once these first 5 chunks are loaded it will start playing the video and load the rest of the chunks in the background, without interrupting the video (given your internet speed can handle it)
a con to this would be that you have to convert all your videos to m3u8 yourself. a tool such as FFMPEG can help with this though.
references
HLS
m3u8
AVPro documentation
I have to design an application where the user is choosing a video and entering a secret message which will be embedded in the video.The video will be split into audio and image frames and the message will get embedded in both the audio and image frames using PGP(Pretty Good Privacy).The audio and image frames will then be combined to form a modified video. Now I have to store this modified video in a server. Then later again I have to extract this modified video from the server. Please can anyone guide me through this? Or provide me better solutions to this problem. I would appreciate that.
I want to create physical .mov or .wmv file from sequence of images for an iphone app, means user will provide me with some images and i will create a video for the user, and if user wants .mov or may be .wmv file, then in that case i will create a video file for the user, and i also want to add sound in that file, now i have searched a lot for this but didn't find anything very use full, can any one tell me is there any tutorial or help full material to do this, or provide me some guidance for how to go about this, thanx and regards Saad
I have come across some sample codes where set of images are added to make a QTmovie.
I am targeting this for OS X platform without any QT frameworks.
I have ague idea of creating a file with extension and embed it with appropriate metadata and find a way to insert images and audio in required format. So when the file is created it can simply be played.
I am not sure of what format/extension is better.
pointers are much appreciated.
Without QuickTime (or an equivalent multimedia framework), what you describe is quite a lot of work. Ordinarily, you would use a video compression algorithm (such as H.264) to encode your images into video, and an audio compression algorithm (such as AAC) to encode your audio track. Then you would write these streams into a container file, such as an MPEG-4 file, which interleaves the streams for playback, contains metadata and indexes and so on. Then for playback, you parse the file, decode the video and audio data, and schedule them for playback, taking care to keep them in sync.
QuickTime does all this (and more) for you, and it would be an enormous undertaking to write it all yourself. Is there some reason why you are running on OS X but cannot use QuickTime?
Given the question is tagged with iPhone, why can't you just use QTKit?
If you had to do it from scratch, you could adopt a very simple solution whereby you store your image sequence as a set of JPEG files (but then you would require libjpeg; use raw RGB or PPM if you must), the audio track as a raw WAV data, and then have another file (a text file you define) that stored timing information, so you would simply stream out the audio, and have the frame numbers of the images stored with their corresponding timecode/sample offset. That is a very simple solution that could be made to work without too much effort.
If you give us some more idea of what you are trying to achieve, we could offer some more specific suggestions.
If you want to write a program to do this, you could use Xuggler in Java to do it. It will allow you to save your final video in a format playable by almost any media player.
Start out by gaining an understanding of how video files (e.g. MP4, Quicktime) actually represent audio and video with this Overly Simplistic Guide to Internet Video.
Then, play around with the MediaTool tutorials. You can write programs that make raw images into video files (see this sample code). Finally, to write a program that makes audio and video that are in sync, see this tutorial; it generates a set of images, and makes some audio noise that is timed to change when a ball hits the edge of a box.
Hope that helps.
Art
I have many videos in .flv and .mp4 formats. I store then in one Windows folder and re-name after downloading so that it becomes easy to find one that I want to play.
It would be best if I can create thumbnail from one of the frames of video file.
Is there a program/utility in which I can open the .flv or .mp4 file, play, pause and take the screen/frame and set it as thumbnail of that file?
I did my best to find it on internet but failed hence thought to reach out to Gurus.
Thanks in advance,
Jay
I think ffmpeg and mencoder can do this