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How can I know the exact bitrate output? - Printable Version

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How can I know the exact bitrate output? - dingo424 - 10-08-2020

I'm using a LG G7, running Android 10. I was curious about the bitrate output when playing 16/44(CD Quality) and MQA mastered songs.

With bit-perfect enabled and everything else is not touched, AudioFlinger output recognizes the audio bitrate correctly, but I realized that in logcat, while playing 16/44 audio, the bitrate is set to 24/48, with the log saying "LGE does not support 44.1 native play backset default Sample Rate(48k)". 
And while playing MQA mastered songs, the MQA flag seems to be untouched, with the log saying "mqa_enable= 0, active_mqa_offload = 0". But in the app, the MQA logo appears with no blue/green light.

Setting the MQA flag checked manually seems to work, with the log saying "mqa_enable = 1, active_mqa_offload = 1", and the bitrate in the log and UAPP is showing 24/176 than 24/44.

So I'm confused, because I heard that UAPP outputs 16/44 to 24/44, and with MQA audio, even though the player is saying "setting mqa flags" at default settings(with bit-perfect enabled), it seems to be not working even though setting MQA flags manually makes it know that it's an MQA audio. It makes me more confusing because AudioFlinger output is recognizing every audio exactly, so it makes me doubt about the logs.

So in short, my question is,
0. is the bitrate shown in logcat trustworthy?
1. Is it normal to be outputting 16/44 audios to 24/48?
2. Is MQA decoding not working in Android 10 in default settings?


RE: How can I know the exact bitrate output? - dwrae - 10-10-2020

AudioFlinger does not know the exact sample rate played, especially when using MQA because that happens after AudioFlinger. You do need to turn on the MQA flag in order for the LG to decode and render MQA. Otherwise you get what you see in the logcat: mqa_enable= 0. I'm not sure why it is confusing for you that no MQA gets decoded when switching off the flag.

0 yes
1. I wouldn't call it normal, but if that is what you see, then that's happening for sure
2. MQA decoding works with the MQA flag turned on as displayed by the app


RE: How can I know the exact bitrate output? - dingo424 - 10-11-2020

(10-10-2020, 01:51 PM)dwrae Wrote: AudioFlinger does not know the exact sample rate played, especially when using MQA because that happens after AudioFlinger. You do need to turn on the MQA flag in order for the LG to decode and render MQA. Otherwise you get what you see in the logcat: mqa_enable= 0. I'm not sure why it is confusing for you that no MQA gets decoded when switching off the flag.

0 yes
1. I wouldn't call it normal, but if that is what you see, then that's happening for sure
2. MQA decoding works with the MQA flag turned on as displayed by the app

Thanks for your reply. Should I expect 24/44 output while playing 44.1khz files? And I wonder if G7 doesn't have a way to output in 44.1khz because it even outputs to 48khz when playing 24/44.1 files with the same message in the log :(

And for MQA, I didn't pay attention to the app's message, just realized that UAPP tells me to turn the flag on to decode MQA whie playing it with flag swithed off :)