[Debconf-video] Smartphone apps + microphones = useful audio ?
Hi all,
There is a lot of talk about using smartphones with suitable apps and
microphones to capture audio and then combining it with video in
post-processing. There are a number of blogs and also demos on youtube[1]
The value proposition is that you can attach a $50 lavalier to the
smartphone and get the same quality audio as you would get from a $500+
Sennheiser kit.
Typical criteria for the app:
- disables ringer while recording or refuses to record unless phone in
silent mode or airplane mode
- disables AGC in Android
- choice of sample rate
- choice of file format/compression scheme
Ideal criteria:
- free software
- available in f-droid
- as well as recording to SD card, can send an RTP stream that can be
received by VLC on other devices
- millisecond timestamps or some kind of remote control or start/stop
co-ordination with video, possibly using an app like qDslrDashboard
- reporting battery and wifi stats over the network to the audio desk
(copy code from Lumicall[3])
Does anybody feel that this option is stable enough to be useful in a
(mini)DebConf environment or other free software event, maybe not for
the main talks but even if it is just for things like interviews, dev
rooms, etc?
Personally, I've observed that I can get hours of usage out of my
Samsung Note 3 using Lumicall, which is streaming VoIP in both
directions and encrypting. This suggests that a device with a suitably
charged battery can offer some value.
Can anybody comment on some issues:
- do any phones offer sufficient pre-amp and ADC circuitry or is it
better to use a small USB sound device with an OTG connector into the
phone to get optimum audio?
- has anybody seen any free software app that can disable AGC? There
are several in f-droid, I checked some already and they don't have this
option. There is a free of charge closed-source app with this feature[2]
- has anybody looked into millisecond time sync for devices in this
category (Android and DSLR)? Looking at an app like qDslrDashboard, I
imagine it could be used to start audio recording in the phone or send a
multicast announcement at the same instant that it sends a start
instruction to the camera.
Regards,
Daniel
1. https://www.youtube.com/watch?v=6mXAIUhG9HY
2.
https://play.google.com/store/apps/details?id=dje073.android.audiorecorderlite&hl=en
3.
https://github.com/opentelecoms-org/lumicall/tree/master/src/org/lumicall/android/ganglia
Reply to: