I use Spotify for all my music needs and was wondering if there was some way to write an app that would allow me to access the music from Spotify and slow songs down and loop portions of the songs. I am a musician, and something like this would help with practicing.
If it can be done, a brief outline of what I'd need to do would be appreciated.
Separately, would this be legal?
You'd have to write that application yourself using libspotify. However, I'm fairly certain the Terms of Service for libspotify disallow modifying the audio. I'm not sure if slowing down counts as "modifying" - that's probably a question for a lawyer.
#iKenndac is correct, but I just wanted to add that modifying the PCM stream given by libspotify is technically against the legal terms & conditions. However, if you do not redistribute such an application (ie, personal and private use only), you'd not be in any legal trouble.
(Disclaimer: I work for Spotify, but am not a lawyer)
You can use Djay for this. Djay have a function so you can play your songs in spotify at slower speed, or faster speed.The function is called key lock/ time stretching and it seems to work on mac running on OSX 10.9 or higher, iphone 4s or better, ipad 2 or nexus devices. Hopefully it will work for more devices soon. It is not the cheapest app in the world but it should work.
Here is a link to the ipad version.
djay 2 - algoriddim GmbH
iphone
djay 2 for iPhone - algoriddim GmbH
and mac
djay Pro - algoriddim GmbH
Related
I currently have an old Galaxy Trend Lite GT S7390 that is so old it's virtually unusable. I want to give it the funtionality of an old mp3 player, but since it has wifi functionality, I thought it would be cool to have an OS that would allow it to work with the Spotify app, however that's ALL I want it to do. I just want it to work with Spotify.
Is this possible? I'm perfectly fine figuring out how to do it, I just need to know if it's technically possible and a direction to begin at.
I haven't tried much yet.
Android is open source. You can modify it how ever you want. You can flash it to any device (support withstanding). But will it support your all your device's specific cheap Chinese hardware? Likely not. You'll probably have to write modules to integrate your specific hardware drivers. That' why most Android phone makers give their own version of Android. However, they have to pay licensing to Google because they are charging you for it. As long as you don't charge for your resulting product, you do not have pay licensing.
Android is written in Java. Here's a link to the project:
https://source.android.com/
I hope your computer can handle running Android Studio. It's a hungry, hungry resource monster.
I am looking to have a Symbian Series 40 application to take a photo using the onboard camera every 5 minutes and then upload the image to a server via GPRS.
Is this possible? I need to know whether this is possible before going deeper into it. Would S60 be better?
Here's a slightly corrected version of the code linked by Mihir (it had an obvious bug and another bug which is probably an interoperability issue) which works on my Nokia 3110 classic: Java ME Image Capture Example
I have very easy question, but I simply have any idea of the answer.
I have developed a small mobile-application using java, for my nokia.
The problem is that when installed on my samsung the application simply crashed.
Then I tried on my other nokia but different model, and I didn't got the normal behavior.
So my question is, does anyone have any idea how companies that develop mobiles applications/games test their software.
Does they have to have all models for all mobiles phones??
Companies that target many phones in many countries usually only let you install the application on your phone if they recognise your handset User Agent in the HTTP headers of the request to download the .jad or .jar file.
There are multiple ways to test an application on many handsets for many mobile network operators.
From simply buying the phones, to establishing commercial parternships with handset manufacturers and mobile network operators, to having a Device Anywhere account.
I don't know if you need all models of all phones. But you will definitely need separate test (and probably different builds) for different phones regarding:
MIDP version
Screen Size
Input Devices
Speed & Memory
Java, in this case is, WOTA (Write Once Test Anywhere) instead of WORA (Write Once Run Anywhere). :-)
Phone specs and Java implementations vary a lot, but within each manufacturers range there will be groups of phones that share the same specs and implementation.
I used to work at a company making J2ME games, what we did there was test on every handset we released the game on, but we had 2 types of test - Complete and Compatability.
We would adapt a version of the game for a specific phone, eg Sony Erricson K800i, and have it thoroughly tested according to the Complete Test spec.
Once that had passed, we then used that build on phone known to have similar specs and good previous compatability with other games (we kept a database of specs and compatability records), eg Sony Erricson W910i, and submit it for a compatability test, which was a bit less thorough and a bit quicker.
Once you've been doing it a while you get to know the capabilities of phones and which phones you could use the same build on, but there is often a bit of guesswork involved :) Sometimes you get matches you wouldn't expect, and sometimes a match you would expect to work doesn't.
Edit: I was going to post this as a comment, but I can't (because i'm an SO noob :), out of interest, what phones are your Nokia's and Samsung?
I can't remember many specific handset names, but here is a quick rundown of compatability across manufacturers:
Sony Erricsons are generally excellent - if it works on one, it will likely work on all SE handsets with the same resolution.
Nokia's are generally good within a certain smaller group eg N95 builds work well on most nokias with the same res that were released after the N95, but some handsets are a bit of a pain.
Samsungs are pretty bad - the J2ME implementation on most is flawed (Hide/Show Notify methods not being called is an example), and the memory and speed are typicly a bit crap.
Motorola phones are not great, but are generally quite compatable with oneanother. Same goes for LG, although their more recent models are much better.
Testing is one of the most labour intensive part of mobile phone development. Typically a company might simply buy a lot of different phones to test on for real, or target a particular subset such only as Series 40 Nokia phones.
But alternatives exist out there where you can remotely deploy your app to phones, such as Nokia's Remote Device Access Services.
One way that might limit the problems is to target J2ME MSA (Mobile Service Architecture) compliant phones, where MSA attempts to reduce variations in vendor implementations of J2ME.
I'm writing a cross-platform program that involves scrolling a waveform along with uncompressed wav/aiff audio playback. Low latency and accuracy are pretty important. What is the best cross-platform audio library for audio playback when synchronizing to an external clock? By that I mean that I would like to be able to write the playback code so it sends events to a listener many times per second that includes the "hearing frame" at the moment of the notification.
That's all I need to do. No recording, no mixing, no 3d audio, nothing. Just playback with the best possible hearing frame notifications available.
Right now I am considering RTAudio and PortAudio, mostly the former since it uses ALSA.
The target platforms, in order of importance, are Mac OSX 10.5/6, Ubuntu 10.11, Windows XP/7.
C/C++ are both fine.
Thanks for your help!
The best performing cross platform library for this is jack. Properly configured, jack on Linux can outperform Windows asio easily (in terms of low latency processing without dropouts). But you cannot expect normal users to use jack (the demon should be started by the user before the app is started, and it can be a bit tricky to set up). If you are making an app specifically for pro-audio I would highly recommend looking in to jack.
Edit:
Portaudio is not as high-performance, but is much simpler for the user (no special configuration should be needed on their end, unlike jack). Most open source cross platform audio programs that I have used use portaudio (much moreso than openal), but unlike jack I have not used it personally. It is callback based, and looks pretty straightforward though.
OpenAL maybe an option for you.
which API or library on which mobile OS is to be used when one needs to write a code to use the phone's IrDA to create the necessary impulses to remote control consumer electronics e.g. a HDD media player?
Is maybe a certain mobile OS better suited for that kind of application than others?
First you need to know that IrDA is not the best choice for remote control. It can be done, but IrDA is by design high speed/low range, you can emulate low speeds but ranges (IMO) are far from practical usage (Nokia e50 is able to control digital camera shutter from 2-3m... with very, very careful aiming). The amount of hacking needed to achieve this is shown here, you basically need to trick IrDA to send correct impulses with correct frequency.
The second thing is that CIR remote control is not as simple as you might think. There are countless standards that differ in used frequency, modulation, wavelength, command codes and so on. You need to know what you want to support. LIRC site can be very helpful in determining that http://lirc.sourceforge.net/remotes/. Approachable explanation of what it all means is available here: http://www.sbprojects.com/knowledge/ir/ir.htm
As for ready made libraries and platforms... I honestly don't know. I've seen it done on PocketPC (nevo among others) and Symbian S60 (irRemote). Haven't seen working J2ME app yet.
Last time I needed the IR remote I hacked it together using IR diode, AVR ATTiny and surprisingly short piece of assembly :)