Tuesday, January 8, 2013

Automatic Audio Recorder Released

Automatic Audio Recorder (AAR) has been released on Google Play:

The application is a slimmed-down version of Babbler Audio Recorder branded for more "sane" users and does not include auto-play/talk features. In other words, it is just a regular voice-activates audio recorder for Android.

Tuesday, June 26, 2012

Babbler RAW file converter tool for PC

Babbler RAW Converter

Use this tool to convert large RAW files (which are in internal Babbler format) to standard WAVE files on your PC. This is very useful for processing of very large files (i.e. 2 hr lectures).

Download the EXE file here: http://itadapter.com/babbler/babblerrawconverter.exe

You have to have Microsoft .NET framework 3.5 installed to run the tool.

Have fun.

Sunday, May 27, 2012

Babbler Pro V 1.2 :: Pre-Recording

Babbler Pro comes with the key new feature - ability to capture sound before recording was triggered. This was requested by our users on a few occasions and this is a great feature for these use-cases:

  • Suppose you want to auto-record snoring at night, so when you start snoring the loud sound triggers the algorithm and recording starts, on the other hand - this does not capture the very onset of the sound event, in other words - by the time decision to start recording is made that particular sound already happened and it is too late. Pre-recording in auto mode allows you to record X milliseconds prior to sound event onset
  • Suppose you are attending a lecture and your professor starts covering the very topic of your most sincere interest. For this setting the manual recording (on button push) is the most appropriate action, however when you push the button - this is already too late because you miss "And now I want to talk about jazz harmonies in baroque era..."(or what not...). Now you can set pre-recording interval to, say 5000 ms = 5 seconds, and the opening statement will be captured

Both intervals are configurable through "Settings" menu item

The pre-recording functionality is available only in paid Babbler Pro Audio Recorder.

Saturday, May 26, 2012

Babbler Pro Audio Recorder Released

Released Babbler Pro Audio Recorder - a paid version of Babbler Audio Recorder app that is completely add-free and will be bringing many more new features in the nearest future, such as:

  • Pre-recording - this will record X seconds prior to event that triggered that auto recording
  • Scheduling - allow users to create named schedules (i.e.: "Going To Bed", "REM Sleep" etc...) and then apply them to recording or playback. This is going to be very useful for self-hypnosis before sleep, when one would be able to set, say "20 minutes gradual fade-out" play of tracks
  • Hypnosis/Learning packs for subconscious study (while falling asleep/while sleeping) - one of the planned packs is 750 select SAT words that would be available for download  

Saturday, April 14, 2012

Babbler Audio Track Export

Recently, I have received multiple questions on the same topic - where are exported files and why Babbler Recorder does not record in MP3 format from the very beginning and needs "Export".

Let me Explain.

Babbler Audio Recorder is a voice activated recorder AND PLAYER, think of it as a multi-track of a sort. for example when "Insanity" play mode is activated it may read many different tracks at the same time, it has a mixer. Because of it it is impossible to store data in compressed format because mixing it in real time would be very problematic for apparent reasons - CPU load. Thats' why Babbler records everything in a "fast buffer" mode - very similar to memory-mapped file, it is called "RAW" file which is internal to Babbler and can not be played on a PC or a MAC.

When you export the track, the RAW track gets through export converter and resulting file is placed by the original track with ".WAV" or ".MP3" suffix.

All tracks are in "SDCARD/Babbler/<your bank>/tk_XXXX.raw.mp3" (or "wav"), where <your bank> is the name of the bank that your track is recorded in, and XXXX is an auto-assigned number during recording.

You can use "Label" option to give the track a meaningful name, such as "scream #2" however it will only display in the application, on disk the file would still be called "tk_XXXX.raw".

"Share" exports the track and runs share dialog. If you don't share then exported track remains in the same folder but you will need to use either a file manager or USB PC transfer to send the file. MP3 and WAV files are playable by regular Android Sound Player after export.

Saturday, March 31, 2012

Babbler v2.0 Released

Babbler 2 released!

Key new Features:

  • Hardware AGC disable/enable - controls devices audio circuitry
  • Software AGC disable/enable - control amplitude processor limits
  • Auto recording start threshold - specify amplitude change percentage that triggers recording
  • Auto consolidate tracks - consolidate tracks right during recording
  • Export to MP3 - export/share tracks as MP3 files, specify bit rate and encoding quality
  • Auto Recording Interval - keep recording even after signal recedes for specified interval

  • Stay  tuned for detailed feature explanation. But briefly, this is really awesome - now I can set "Auto rec threshold" to low %, say 2% and Babbler will capture any small difference in sound pressure level. This is very useful for recording snoring at night. 

    MP3 export is a must for my piano practice, I just email sound clips (that are now small) back to myself!

    About this new thin hand on a VU meter - it shows you software AGC level - the more to the right - the less sensitive the app becomes. When software AGC is turned on, Babbler decreases max volume level when signal spills-over 100% mark, thus attenuating amplitude detector down.


    Wednesday, March 28, 2012

    Android Recording Quality and AGC(Automatic Gain Control)

    A few days ago I received an email with complaints regarding "horrible recording" quality in the app. The fact is - when dealing with uncompressed audio (non-MP3 or other lossy format) we can't really affect quality - the problem is with particular device. Most Android recorders either use built-in MediaRecorder class or use direct audio interface, in any case it is impossible to make it sound good if your mic gives crappy data to the system.

    AGC stands for Automatic Gain Control - a feature that regulates your device microphone sensitivity depending on signal level. Not all Android devices have this feature implemented in the same way or even available at all.

    Take Acer Iconia Tab A500 - very good device, however the AGC feature after firmware update to Android 3.1+ became horrible. I mean unusable. Not only this affects our Babbler application, but any app that uses mic, be it SKYPE or Google Talk - sound just phenomenally distorted and over-processed. In Babbler we can look at raw samples - and it is clear that AGC in A500 just clips the signal in good 85% of cases. The AGC is absolutely unpredictable as it sometimes clips even sounds of medium intensity.

    Starting Android 2.x there is an option in AudioSource that allows developers to instruct audio system not to use AGC circuitry - VOICE_RECOGNITION gives direct mic stream back to the kernel at the expense of degraded mic sensitivity. Babbler v2 has a whole new set of settings to enable/disable hardware AGC.

    The best Android device we have seen/heard so far is Motorola Atrix II - the sound quality is phenomenally crisp and tone rich, also the speaker is very loud and gives good amplitude frequency response.