I'd like to built an application for analysis and classifications of tracks (everyday sound tracks instead of speech or music) recorded and/or streamed by soundcloud.
The idea is to use existing soundcloud infastructure (database, record, share, comment...) and just add an analysis level in between.
It is possible trought the API to access to the track binary files? We'd like to process some of them.
Is there also a way to access to the audio stream durring recording? it's for live classification task.
Thanks
Boris
Some users allow for their tracks to be downloaded, others don't. On one of the downloadable tracks, the track information will have a download_url, and you can download and process that however you like. As for accessing the stream during recording, at that point in time, the file doesn't exist on SoundCloud yet (it's only uploaded once the recording is complete). You could write your own Flash recorder or use the Web Audio API to get audio information during recording.
Related
I am creating an application that uses Mozilla's Deep Speech API to transcribe the user's speech to text. The input requires audio files with some sort of format and in order for this app to work, I will need to continuously send these audio files to my flask server while the user is recording audio.
I have seen that most flutter plugins only allow you to record, pause, and stop, however, I need to find a way to keep on recording while also sending audio files. If anyone has found a way to accomplish this using Flutter.io's recording plugins, any guidance and information would help.
My backup plan is to use one of Flutter's Speech-To-Text plugins like this one: https://pub.dev/packages/speech_to_text#-example-tab-, and then to send over the text to my backend server through a websocket. However, I don't know what kind of API they're using to transcribe and how accurate the text gets transcribed to.
Any ideas on how to accomplish this? Or would anyone happen to know if another framework like Swift/React-Native can accomplish this?
Is it possible to use libspotify to obtain the URI of a track and play it using a higher level Media Player? For instance, I'm interested in doing this with a QMediaPlayer in Qt. I ask this because one of Spotify's sample applications uses lower level API's to write the samples directly.
I'd rather do this simpler, similar to how Grooveshark's API works by returning a URL for the track and simply setting that on the high level media player.
No, the only way to get audio for a Spotify track is using libspotify's audio delivery callback, which delivers raw PCM data.
I am trying to create a streaming video DVR like functionality in an app I am developing. I have an HTTP Live Stream that I have successfully gotten to play on the iPad. I want the user to be able to push the "Record" button, and begin recording the video that is currently playing from that point. This video file will be accessible from the app or from the camera roll. Currently, I am using the MPMoviePlayerController object to play the video stream. I do not see any methods of accessing the data from the object in Apple's documentation. Here are some thoughts I had on ways of going about this.
1) Somehow access the video data from MPMoviePlayerController, and write this to a file. Or use another type of player object that will allow me to play the video and access the currently playing data.
2) Implement some sort of screen capture recording that gets a video capture of the iPad's screen. This would allow me to record the video in a "screenshot" sort of way.
3) Locate the HTTP Live Streaming video segments where they are stored by MPMoviePlayerController. Presumably they need to be stored somewhere on the iPad for playback. Is there a way of accessing these files?
4) Manually download the stream video segments over http while streaming the file. This seems like its not ideal since the stream would have to be downloaded twice.
5) This could work. Periodically download the video segments to the iPhone. Set up a local http server on the iPhone and server the videos to the MPMoviePlayerController. This way the video segments could be marked for recording and assembled into a video.
6) I do have control of the streaming server. I could write some server side code to record the video on the server end, then send the video to the iPad after the fact. I would rather not do this.
Has anyone done any of these things? Ideally the iPhone would just be able to access the video data somehow and easily record it. I would rather not get into options 4, 5, or 6 (above) if I don't have to.
Thanks in advance.
DVR on the device is somewhat not encouraged, due to the limited space available and other factors like battery life, processing power, cleanup procedures after the user stops the dvr, etc.
If you want to achieve DVR playback on iOS devices (or other devices using HLS), I suggest you keep the video server side. The live stream is already captured and segmented server side, all you would have to do is keep the segments a bit longer, instead of deleting them. By using the EXT-X-PLAYLIST-TYPE and EXT-X-MEDIA-SEQUENCE tags, you can suggest to the player that he's opening a live stream which has DVR (earlier) video available.
Alternatively, you can use a server that does that out of the box, for example Wowza. Here's an article on how to achieve this with Wowza
I am in need for some help as I am stuck with a problem with my current IPhone application. I won't go into every details but the mainline is as follow:
I am currently playing videos from a remote URL. Everthing up to this point is working. But we need to add a certain validation as if the video exists on the local IPhone, play this version and otherwise, get the remote version. I get these informations from an XML feed and have the name of the video and it's remote URL.
I've implemented the ALAssetLibrary as a way to retrieve the locals video and transfered 3-4 videos with custom names. After some struggling, I could play these local video. But while I loop through them, all I get is names like 00001.jpg, etc.
Is there any way to get a local video name ? I don't mind if this needs another library but I would appreciate if someone could point me a way of doing it.
Thanks for your time,
AP
You don't have access to the local filenames, and even if you did those filenames would probably not be what you are expecting (i.e. Apple can and probably does rename them while saving them to the Camera Roll).
You can check the metadata on the ALAssetRepresentation for the video to see if a suitable name or other identifier can be found in there. You might also be able to retrieve the raw data and hash it, but that would fail if Apple does any recoding or metadata alteration when saving the video. If your program itself downloads and saves the videos to the Camera Roll using writeVideoAtPathToSavedPhotosAlbum:completionBlock:, you could store the returned assetURL to remember the correspondence. Or you could save the videos to your app's local storage instead of to the Camera Roll, but that would prevent the user from managing the videos with Apple's photo application and such.
I'm writing an app, part of which allows the user stream/play videos. I want to restrict the functionality so that they can only stream videos if they have a WiFi connection. I will then save the video so that when they have a 3G only (or lesser) connection they can't stream videos and can only replay videos that are saved on the phone.
Ideally, I'd like to get MPMoviePlayerController to stream/play the movie and then access the movie data and save it. However, the MPMoviePlayerController api doesn't seem to support access to the movie data.
I'd like to avoid and download-then-play scenario. Any ideas?
Two solutions come to mind.
Both this solutions require that the file is in a format that can be played progressive, e.g. that you don't need the whole file to be able to play it (but that would be a prerequisite anyway).
use a thread to download the data and append it to a file, and play the file from another thread. Now, that requires that you can handle EOF events in the MPMoviePlayerController and pause the playing until the cache file is appended to and then resume for the same point.
So far what I've seen people doing this it doesn't work because MPMoviePlayerController can't handle the EOF event. (not tested it my self yet) [Caching videos to disk after successful preload by MPMoviePlayerController
Skip the playing from a file and setup a local HTTP server and stream from that (on localhost). This is also not tested.
The idea is that MPMoviePlayerController would handlle the event of missing data better from a HTTP stream then from reading the file directly.
Downside might be that it is less efficient, but I think that is a minor increase in CPU. I don't know if the network interface would handle it, but I'm assuming it's not an issue.
I leave this answer as a wiki, because I don't have a working solution but I too want one.
There is a way to make this work, but you have to write your own HTTP Live Streaming downloader.
Basically, you parse the .m3u8 file (it's a pretty simple standard, but can get tricky with alternate streams and the possibility that the stream will simply drop out and need a new playlist to continue) and then download the chunks in .ts format to your local storage, say the Documents folder or Caches etc.
Then you'll have to set up a local HTTP server to allow the MPMoviePlayerController or AVPlayer to access the files over HTTP (since they won't touch a local file path), including a re-coded playlist file pointing to the local files, which you'll have to create yourself from the original playlist(s).
CocoaHTTPServer works great for this.
Once you've done all that, it works great. It's unavoidable that you get a little delay while you download the first chunk or two before presenting your local HTTP URL to the movie player, but after that you get seamless download, recording and preview playback.
Good luck!
the iPhone is using progressive download so it will not save on the device. For that you need to explicitly download it and then play the video from your local folder.