It is possible to implement a feature that allows users to watch videos as they are uploaded to server by others. Is html 5 suitable for this task? But flash? Are there any read to go solutions, don't want to reinvent the wheel. The application will be hosted on a dedicated server.
Thanks.
Of course it is possible, the data is there isnt it?
However it will be very hard to implement.
Also I am not so into python and I am not aware of a library or service suiting your requirements, but I can cover the basics of video streaming.
I assume you are talking about video files that are uploaded and not streams. Because, for that, there are obviously thousands of solutions out there...
In the most simple case the video being uploaded is already ready to be served to your clients and has a so called "faststart atom". They are container format specific and there are sometimes a bunch of them. The most common is the moov-atom. It contains a lot of data and is very complex, however in our use case, in a nutshell, it holds the data that enables the client to begin playing the video right away using the data available from the beginning.
You need that if you have progressive download videos (youtube...), meaning where a file is served from a Webserver. You obviously have not downloaded the full file and the player already can start playing.
If the fastastart atom was not present, that would not be possible.
Sometimes it is, but the player for example cannot display a progress bar, because it doesnt know how long the file is.
Having that covered the file could be uploaded. You will need an upload solution that writes the data directly to a buffer or a file. (file will be easier...).
This is almost always the case, for example PHP creates a file in the tmp_dir. You can also specify it if you want to find the video while its being uploaded.
Well, now you can start reading that file byte by byte and print that data to a connection to another client. Just be sure not to go ahead of what has already been recieved and written. You would probaby initiate your upload with a metadata set in memory that holds the current recieved byte position and location of the file.
Anyone who requests the file after the uploaded has started can just recieve the entire file, or if the upload is not yet finished, get it from your application.
You will have to throttle the data delivery or pause it when the data becomes short. This will appear to the client almost as a "slow connection". However you will have to echo some data from time to time to prevent the connection from closing. But if your upload doesnt stall, and why shoud it?, that shouldnt be a problem.
Now if you want to have someting like on the fly transcoding of various input formats into your desired output format, things get interesting.
AFAIK ffmpeg has neat apis which lets you directly deal with datasterams.
Also handbrake is a very good tool, however you would need to take the long road using external executeables.
I am not really aware of your requirements, however if your clients are already tuned in, for example on a red 5 streaming server, feeding data into a stream should also work fine.
Yes, take a look at Qik, http://qik.com/
"Instant Video Sharing ... Videos can be viewed live (right as they are being recorded) or anytime later."
Qik provides developer APIs, including ones like these:
qik.stream.subscribe_public_recent -- Subscribe to the videos (live and recorded)
qik.user.following -- Provides the list of people the user is following
qik.stream.public_info -- Get public information for a specific video
It is most certainly to do this, but it won't be trivial. And no, I don't think that you will find an "out of the box" solution that will require little effort on your behalf.
You say you want to let:
users watch videos as they are uploaded to server by others
Well, this could be interpreted two different ways:
Do you mean that you don't want a user to have to refresh the page before seeing new videos that other users have just finished uploading?
Or do you mean that you want one user to be able to watch a partially uploaded video (aka another user is still in the process of uploading it and right now the server only contains a partial upload of the video)?
Implementing #1 wouldn't be hard at all whatsoever. You would just need an AJAX script to check for newly uploaded videos, and those videos could then be served to the user in whatever way you choose. HTML5 vs. Flash isn't really a consideration here.
The second scenario, on the other hand, would require quite a bit of effort. I am guessing that HTML5 might not be mature enough to handle this type of situation. If you are not looking
to reinvent the wheel and don't have a lot of time to dedicate to this feature than I would say that you would be out of luck. You may be able to use ffmpeg to parse partial video files and feed them to a Flash player, but I would think of this as a large task.
Related
Summary:
While a video is streaming in the internet browser, packets of mp4 files are being downloaded.
I would like to write some code that saves the packets into one file so the video is preserved after it is done streaming.
I think this could be done by taking the packets in as byte files, removing how ever many bytes the addressing header at the front is made out of, and then concatenating the rest, but I will be the first to admit that I have never done anything like this before and don't really know what I am doing.
If anyone out there has experience with with this kind of thing, I am not looking for much, just a few words to point me in the right direction, or at least keep me from going too far in the wrong direction. I am really just coming at this project with half a CS degree and some notions about what to google right now.
Specific Questions:
Do you know how I can access the data packs being downloaded from the internet? For example, if I wanted to make a script that grabbed each of the mp4 data packs as they came in, what kind of command would I use to access them?
Do you know what would be the best way to save the video file? Should I access the data packs as they come in? or should I access them later, as they have been strung together by the media player? Is the second part even possible or would the data be protected by that time?
If you don't have answers to these questions, are you able to give me a reference to a place the does? I haven't been able to find this subject on stack. Even some good keywords to search for would be useful.
Thanks for taking the time to read,
-Coder 357
TLDR: Trying to make code or script to save the mp4 packets into video files as they are streamed.
Progress So Far:
I suppose all I have done is press f12 and open up the network activity section of the internet page, streaming the video I want to capture. I know that I am rapidly fetching mp4 files in the kb and mb size range. That is what lead me to my conclusion that I will likely need to string these mp4 files together into one file, after removing any extra bits and bytes at the front and end.
That being said, I don't have an understanding of how my media player holds the data, so there may be a much more convenient way to do this that I am not seeing.
Goal:
My best case expectation for the project is to have a program or script which can be run from the command line and will then combined mp4 data packets, from a given website, into a single video file.
What I'm doing
Basically I'm writing simple a Q&A site with an option to create links to specific positions in media files. As of now the app is intended to be used in LAN environment only.
I have put a video in appRoot/public folder and created a view using
html5 video tag.
It works and even seeking is available. Wow...
What I don't understand
I'm clueless as to the tech behind and its limitations.
It just worked, so I don't even know a key word to hit google with.
What I know
With the way I'm doing:
No encryption
No way to prevent users to save video files
No automatic trans-coding available
The real question
What is the name of the tech behind.
How well can rails handle streaming and seeking requests with the way I did as compared to using dedicated video streaming servers or gems.
As long as your underlying web server understands how to handle the MIME types for video, and responds correctly to byte range requests - as it seems to be - that's all you need. The underlying mechanics of streaming video with HTML5 is that the browser asks for a chunk of content as a range of bytes from the source (enough to keep the buffer full) and the server delivers it.
You might want to look at using ffmpeg to optimize your videos so that the metadata is in the right place in the file to start streaming quicker.
You've correctly pointed out the limitations of the solution in your environment. The other thing to be aware of is capacity - if the videos are long and a lot of people are accessing them concurrently then without caching (in a LAN via a caching proxy or on the internet via a CDN service) your server capacity may be stretched
Is there any way, using currently available SDK frameworks on Cocoa (touch) to create a streaming solution where I would host my mp4 content on some server and stream it to my iOS client app?
I know how to write such a client, but it's a bit confusing on server side.
AFAIK cloudKit is not suitable for that task because behind the scenes it keeps a synced local copy of datastore which is NOT what I want. I want to store media content remotely and stream it to the client so that it does not takes precious space on a poor 16 GB iPad mini.
Can I accomplish that server solution using Objective-C / Cocoa Touch at all?
Should I instead resort to Azure and C#?
It's not 100% clear why would you do anything like that?
If you have control over the server side, why don't you just set up a basic HTTP server, and on client side use AVPlayer to fetch the mp4 and play it back to the user? It is very simple. A basic apache setup would do the job.
If it is live media content you want to stream, then it is worth to read this guide as well:
https://developer.apple.com/Library/ios/documentation/NetworkingInternet/Conceptual/StreamingMediaGuide/StreamingMediaGuide.pdf
Edited after your comment:
If you would like to use AVPlayer as a player, then I think those two things don't fit that well. AVPlayer needs to buffer different ranges ahead (for some container formats the second/third request is reading the end of the stream). As far as I can see CKFetchRecordsOperation (which you would use to fetch the content from the server) is not capable of seeking in the stream.
If you have your private player which doesn't require seeking, then you might be able to use CKFetchRecordsOperation's perRecordProgressBlock to feed your player with data.
Yes, you could do that with CloudKit. First, it is not true that CloudKit keeps a local copy of the data. It is up to you what you do with the downloaded data. There isn't even any caching in CloudKit.
To do what you want to do, assuming the content is shared between users, you could upload it to CloudKit in the public database of your app. I think you could do this with the CloudKit web interface, but otherwise you could create a simple Mac app to manage the uploads.
The client app could then download the files. It couldn't stream them though, as far as I know. It would have to download all the files.
If you want a streaming solution, you would probably have to figure out how to split the files into small chunks, and recombine them on the client app.
I'm not sure whether this document is up-to-date, but there is paragraph "Requirements for Apps" which demands using HTTP Live Streaming if you deliver any video exceeding 10min. or 5MB.
I've got an app that currently ships with all the videos it can play embedded in it. This doesn't scale well, and unless you want to play all the movies, wastes disk space. It also makes it less desirable to upgrade the app because you have to re-download all movies.
What I would like to do is download the movie on the fly, play it back while downloading, and then if it's successfully downloaded, save it to the file system so that next time they want to watch it, it streams from the local file.
I can do whatever is needed to the video, but currently I'm serving it up as an .mp4 file from Amazon S3, with a mimetype of video/mp4, and so the first half of my issue works fine: the movie downloads, and MPMovieViewController will start playing it as soon as it thinks it has downloaded "enough."
Is there any way to tap into the cache of that video file so that I can save it and control how long it resides on the filesystem? This seems like it would be the easiest approach.
I am targeting iOS 5+6, but if the only solution available required iOS 6, I would consider it also. Thanks!
UPDATE: Using AFNetworking, I am now half-way there, I think. I am downloading the video file from the server, and listening for the download progress. Once I see 25% of the video has been downloaded, I start playback on the local file using an MPMoviePlayerController.
The main issue I'm running into now is playback seems to get screwed up. It's going along fine, 25% downloaded, playback starts... download continues normally... then the file finishes downloading completely, and shortly thereafter video freezes. The onscreen playback timer still indicates playback is ongoing and I don't see any "playback finished" type notifications, but the video is frozen. My guess based on the behavior is that perhaps the initial buffer for the video playback was used up, and it isn't detecting that more video is available on disk now?
Is there any way to interact with MPMoviePlayerController to let it know periodically to refresh the buffer it's playing out of? Or some other way to handle this situation?
UPDATE: Make sure to see the newer answer from #TomHamming.
I have yet to find a conclusive answer, but at this time I believe the answer is: you can't reliably do this. At least not without a lot of work which seems too much like a hack. I filed a feature request with Apple as it really seems like this should be possible with some adjustments to MPMoviePlayerController.
I will go over the variety of things I tried or considered, and the results I encountered.
Pass MPMoviePlayerController a URL to your movie file, which allows it to stream, and then pull the file out of the cache it was saved into, into your local Documents folder. Won't work, as of iOS 6. I filed a feature request with Apple, but as it stands now there's no way to get your hands on the file they are downloading, AFAIK.
Start downloading the movie file with NSURLConnection (or something like AFNetwork), and then when a "decent amount" has been downloaded to the device, pass the file URL to the MPMoviePlayerController and let it stream from disk. Sort of works, but not well. Three problems:
It's really hard to know when to start playing the file. I haven't figured out the algorithm Apple uses, and so I always erred on the side of caution, waiting for 25% to be downloaded before playing.
The MPMoviePlayerController interface provides no sense of the movie being streamed, as it does when Apple is doing the calculations via the network. It appears to the user that the file is totally downloaded when it really is not.
And most importantly, MPMoviePlayerController seems to not work well with playing a file that is not completely downloaded. I experienced playback problems once the file finished downloading, or if the player caught up with the amount downloaded, and never found a graceful way to handle these situations.
Same procedure as above, but use AVFoundation classes to more finely control the playback process, and avoid the issues described above regarding playback stopping, etc. Might work, but I want all the features of MPMoviePlayerController. Re-implementing MPMoviePlayerController myself just to get this one feature seems like a waste of time.
Same procedure as #1 above, but run a small web server in your app to handle streaming the video from the disk to MPMoviePlayerController, with the hope being that the streaming would work more like it normally does when streaming the file directly from an external web server. Works, but results were still sporadic and performance seemed to suffer. I did my test with CocoaHTTP. I decided against this approach because it just felt like a terrible hack.
Run a lightweight HTTP proxy, thus intercepting the downloaded movie file data as it gets streamed from the internet into your MPMoviePlayerController. Not sure if this works or not. I was not able to test this yet, as I have not found a lightweight HTTP proxy written in Objective-C, and at this point don't feel like implementing one just to try this experiment. It seems like the next easiest of all these hacks to implement -- if you don't have to write the proxy!
At this point I've decided to go the less-hacky, but also less user-friendly route of simply downloading the file completely, and then passing it to MPMoviePlayerController, until a better solution comes along.
You can do this as of iOS 10 with AVAssetDownloadTask. See this WWDC 2016 session and this documentation.
Alternatively, if your movie isn't DRM'd, you can do it with AVAssetResourceLoaderDelegate, which effectively lets you give an AVPlayer an arbitrary stream of bytes. See this walkthrough.
A potential client has come to me asking for a an app which will stream a six hour audio file. The user needs to be able to set the "playback head" to any position along the file. Presumably, this means that the app must not be forced to download the entire file before it beings playing back starting at an arbitrary
An added complication -- there are actually four files which need to be streamed and mixed simultaneously.
My questions are:
1) Is there an out-of-the box technology which will allow me random access of streaming audio, on iOS? Can this be done with standard server technology and a single long file, or will it involve some fancy server tech?
2) Which iOS framework is best suited for this. Is there anything high-level that would allow me to easily mix these four audio files?
3) Can this be done entirely with standard browser technology on the client side? (i.e. HTML5)
Have a close look at the MP3 format. It is remarkably easy and efficient to parse, chop up into little bits, and reassemble into a custom stream.
Hence rolling your own server-side code to grab what you want and send to the client will not be as crazy or difficult as it may sound.
MP3 is also widely supported by various clients. I strongly suspect any HTML5 capable browser will be able of play the stream you generate via a long-lived bit-rate regulated HTTP request.