I have a video url (either progressive download or streaming) and I want to determine its format to check if it complies with Android's supported media formats. How can I check this? Is it enough if it works on the emulator?
(as far as I understand testing it on a device is not a warranty since some Android devices might support formats that others do not)
Testing it on device is not a warranty as you said. I agree. Documentation itself suggests us to test on as many different devices as possible, and this is something we can only learn through experience.
As of now I haven't come across a method in MediaPlayer/VideoView which could extract meta information of Videos.
can you have a server side script which tells you the video's details?
Related
We're creating a range of apps that record user's voice for a wide range of applications. Users can register their ideas, or describe a scene, or give educational tips and notes to someone else.
We need to choose a file format that satisfies these conditions:
Better to be playable natively in Android, iOS and web
Better to reduce the cost of encoding-decoding
Better to reduce the cost of development (we're not sound experts)
Storage is not a big deal, so compression is not important, but network traffic IS a big deal, so for that reason better to be as compact as possible
The most obvious choice coming to mind is MP3, but to our surprise, MP3 encoding is not supported in Android Studio out of the box.
We searched and tried to find best practices for this, and again, to our surprise there is not much written in spite of huge usage of sounds and voices everywhere.
For example, in this post it's written that MP3 is the most used file format, and then ACC. But we're totally stranger with AAC.
So, what audio format is natively supported in all medias, both for recording and playing back?
The file format can be .AAC, is compressed, compatible with iOS, Web and Android (3.1 or higher) and is developed by Nokia and Sony (This last one is extra information).
You can see at wikipedia all its compatible OS: AAC Wikipedia
It is compatible with WebOS.
For the past month I have been searching over the Internet for ways to implement recording live video from an application on Android and sending it over to a server, but the more I research the more confused I get.
First of all, I am looking for a streaming protocol that can be used for iOS also in the future, so I came to a conclusion that DASH(Dynamic Adaptive Streaming over HTTP) is the ideal solution.
In addition, the recent Android framework, ExoPlayer, support this feature.
Furthermore, I do not wish to use a Live Streaming engine such as WOWZA.
Secondly, based on my research I also concluded that any HTTP server can be used to receive the "chuncks" of data, but I must have a streaming server to be able to stream the video back to the users.
I believe this process is quite complex but I will not give up until I successfully make it work.
Lastly, my question is, what Server, Protocol should I use to be able to achieve this ? And how to convert video directly and send to server ?
Looking at your questions re protocol and server:
A 'streaming protocol that can be used for iOS also in the future'
It probably depends what you mean by 'future. At the moment apple require you to use HLS on iOS for any video on a Mobile Network (cellular) which is over 10 mins long. DASH is establishing itself as the industry standard so this may change and apple may accept it also, but if you need something in the near future you may want to plan to support DASH and HLS.
What server should you use for streaming
Streaming video is complex and the domain is fast changing so it really is good to use or build on a dedicated streaming server, if you can. These will generally have mechanisms and/or well documented procedures for converting input videos to the different formats and bit rates you need, depending on the reach and user experience goals you have. Reach will determine the different encodings you need, different browsers and devices supporting different encodings, and if you want your user to have good experience avoiding buffering you will want multiple bit rate versions of each format also - this allows DASH and HLS provide Adaptive Bit rate Streaming (ABR) which means the clients can select the best bit rate at any given time depending on network conditions. Video manipulation, especially transcoding, is a CPU intensive task so another advantage of dedicated streaming server software is that it should be optimised as much as possible to reduce your server loads.
If you do decide to go the streaming server route, then there are open source alternatives, as well as Wowza which you mention above, such as:
https://gstreamer.freedesktop.org
These have plugins that support ABR etc - if you search for 'GStreamer streaming server ABR' you will find some good blogs about setting this up.
I'm making an app that needs to send a video feed from a single source to a server where it can be accessed by desktop browsers and mobile apps.
So far, I've been using Adobe Media Server 5 with a live RTMP stream. This gives me about a 2.5 second delay on desktop browsers, which gives me no native support for iOS, but leaves me with the option to use Air to export the app for iOS, which produces a minimum 5-6 second delay.
The iOS docs strongly recommend the use of HTTP Live Streaming which segments the stream into chunks and serves it using a dynamic playlist in a .m3u8 file. Doing this produces a 15+ second delay in desktop browsers and mobile devices. A Google search seemed to reveal that this is to be expected from HLS.
I need a maximum of 2-4 second delays across all devices, if possible. I've gotten poor results with Wowza, but am open to revisiting it. FFMpeg seems inefficient, but I'm open to that as well, if someone has had good results with it. Anybody have any suggestions?? Thanks in advance.
I haven't even begun to find the most efficient way to stream to Android, so any help in that department would be much appreciated.
EDIT: Just to be clear, my plan is to make an iOS app, whether it's written natively or in Air. Same goes for Android, but I've yet to start on that.
In the ios browser HLS is the only way to serve live video. The absolute lowest latency would be to use 2 second segments with a 2 segment windows in the manifest. This will give you 4 seconds latency on the client, plus another 2 to 4 on the server. There is no way to do better without writing an app.
15 Second delay for HLS streams is pretty good, to provide lower latency you need to use a different streaming protocol.
RTP/RTSP will give you the lowest latency and is typically used for VoIP and video conferencing, but you will find it very difficult to use over multiple mobile and WiFi networks (some of them unintentionally block RTP).
If you can write an iOS app that supports RTMP then that is the easiest way to go and should work on Android too (only old Androids support Flash/RTMP natively). Decoding in software will result in poor battery life. There are other iOS apps that don't use HLS for streaming, but I think you need to limit it to your service (not a generic video player).
Also please remember that higher latency equals higher video quality, less buffering, better user experience etc. so don't unnecessarily reduce latency.
can anybody tell how to play flv file in video view in android give example
Thanks
In general you can't. The stock version of Android doesn't come with a parser capable of parsing whatever proprietary standard that Adobe has. However, there is a good chance that vendors have added their own parsers, but that chances that FLV is one of them is extremely low. Even if you did find a vendor who has included, you're pretty much guaranteed that your app won't behave the same on every phone.
I'm researching the development of an Android (2.2) app/service that will enable users to record short (I do emphasize short, < 30seconds) video on their phones and then upload that video (HTTP) to a server that will then transcode the video to other formats. That same user can download videos from other Android users and play them.
Now, I get a bit lost with everyones recommended approaches to all the issues in doing something like this because I haven't seen any ask this in a cohesive context. Ideally I would like a non commercial solution to this (as in no vendor/service being needed for the the video hosting/transcoding), but, feel free to include those as a recommendation (I've marked this as a wiki) as I know many like to use youtube and vimeo for the middle layer in all this.
The questions are
What server technologies do you
recommend for hosting and
transcoding?
What technology do you
recommend for streaming the video (it
would be nice to offer a high and
low quality encoding depending on
the users network connection)
What video format and software do you recommend for converting the uploaded video on the server to be viewable later by other Android owners.
Im assuming it's bad to do any transcoding on the phone prior to upload (battery/proc issues), but, if I'm wrong with that assumption what do you recommend?
Some things that may help you...
The video will only need to render on an Android device, and in the future in a webkit html5 browser.
Bandwidth isnt cheap (even with numerous 30 second videos), so a good mix of video quality and video file size is important (streaming if needed to ensure quality vs. download).
This is for android 2.2 devices with a video camera of course and medium to high density screen of 800x400 min.
Open source solutions (server to receive the uploads, code to do the transcoding, server to do the streaming) are preferred, but not required.
CDN's are an option, but I don't think that really figures in to the picture right now.
Check out this page to see all the video formats that Android supports for encoding and decoding.
http://developer.android.com/guide/appendix/media-formats.html
For encoding use FFmpeg or a service like encoding.com