Audio record block problem in Android 6-7-8

[Caps CC]

In Android 6-7-8 I cannot get working the Audio Record block in order to record the phone calls audio from the Voice call audio source.

It worked perfectly in Android 5, but in Android 6-7-8 I always get the java.lang.RuntimeException: start failed

I suspect it is a problem related to permissions, but it seems all possible permissions are enabled.

What is it possible to do to make it working to record the phone calls ?

Claudio

[Henrik "The Developer" Lindqvist]

As the doc say:

Note! Recording phone calls from the Voice call, Voice downlink or Voice uplink audio sources, is illegal in many countries and do not work on most devices.

See: https://llamalab.com/automate/doc/block/audio_record_start.html

[Caps CC]

Hi Henrik

I know but that (law concerns) is another problem. I am looking now for a technical solution for unlocking the Voice call source and get it working in Automate on LG G6 (Android 7, rooted with Magisk), do you have any suggestion for a fix ? I know there is LGIncallUI.apk to get native call recording on G6, but I would prefer keep control of the audio recording inside my Automate monitoring application. On my old G3 (Android 5) it did work like a dream.

[Henrik "The Developer" Lindqvist]

I haven't fully researched how it's done, but i think it requires installing custom kernel drivers, which is something i'm likely woundn't do anyway.

[Caps CC]

Hi Henrik

I am reading about the question of phone call recording in Android 7+ and, besides problems specific of the brand/device, the first point is that in order to record from VOICE_CALL, in Android 7+, the app needs the CAPTURE_AUDIO_OUTPUT permission, that is included in all the apps that want to record the phone calls, but it seems missing in the manifest.xml of Automate (nor in any of its extensions).

Then in order to try to get the Audio Record block working with VOICE_CALL - IF you are interested in supporting phone call recording in Automate - you could consider to add such permission (may be in the Telephony permission extension). In fact at present, the call to the MediaRecorder API in the Audio Record block is simply refused by Android when the audio source is VOICE_CALL likely due to the lack of the CAPTURE_AUDIO_OUTPUT permission.

Let me know what you think about.

Claudio

[Henrik "The Developer" Lindqvist]

The CAPTURE_AUDIO_OUTPUT permission is for system apps only.

[Caps CC]

Yes, but what is a "system" app ? In a rooted device, I can install Automate (maybe it is enough one of its extension) in /system/priv-app.

This is in fact what it does the latest releases of the Call Recorder made by Skvalex, that is one of the few app that at present really can record the phone calls on most Android 7+ devices despite the Google obstructionistic police. We can try the same way.

For most safety and transparency, you could even think to build a separate new extension with the only purpose of testing this approach.

[Henrik "The Developer" Lindqvist]

I haven't researched system apps much, but i think they have to be signed with the same key as the OS itself.

Including it the app is very risky since Google is currently cracking down on Call recording apps.

[Caps CC]

I found that the free app ACR (Appliqato) records both uplink and dowlink voice call with high quality on Android 7.0 (tested LG G6).

I will analyze further to understand how it can achieve this result.