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[BUG] Audio loosing quality, even changing the bitrate to a bigger value
#1
Bug 
I was converting this video: [attachment=517]
I set x264 and audio = aac 255kbps low complexity(before the source loading)
and when the job was finished, the quality was worse than the source ( Here is the job finished: [attachment=518] )
I tried with better qualities, and the video sounds like the same poor quality. 

Here is the debug output (with only the first try): [attachment=519]
I use the 2018.08.19.1 version in Windows 7 x64

Cu inky
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#2
Looking at the output.
Sound isn't as good since it the original is:
stereo, 432kBit/s, 8kHz
and the reencode is:
mono, 78 kbit/s, 8kHz sampling
so no surprise that the reencode doesn't sound as good.
Problems seems to be that MediaInfo doesn't report the sampling rate which causes the ffmpeg audio encoder to fall back to a lower sampling rate.
It only reports:
Quote:Audio
Count : 277
Count of stream of this kind : 1
Kind of stream : Audio
Kind of stream : Audio
Stream identifier : 0
StreamOrder : 0
FirstPacketOrder : 0
ID : 192
ID : 192 (0xC0)
Format : MPEG Audio
Format : MPEG Audio
Commercial name : MPEG Audio
Internet media type : audio/mpeg
Duration : 1978
Duration : 1 s 978 ms
Duration : 1 s 978 ms
Duration : 1 s 978 ms
Duration : 00:00:01.978
Duration : 00:00:01.978
Compression mode : Lossy
Compression mode : Lossy
Delay : 0.000
Delay : 00:00:00.000
Delay, origin : Container
Delay, origin : Container
Delay relative to video : 0
Delay relative to video : 00:00:00.000
and MPlayer reports:
Quote:AUDIO: 8000 Hz, 1 ch, mpeg2, 144.0 kbit/112.50% (ratio: 18000->16000)
ID_AUDIO_BITRATE=144000
ID_AUDIO_RATE=8000
ID_AUDIO_NCH=1
which is why Hybrid uses the mplayer values.
FFmpeg reports:
Audio: adpcm_adx, 48000 Hz, 2 channels, s16p, 432 kb/s
So different format and values.
-> I'll look into it today after work and work out a workaround for this.

Cu Selur
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#3
Small update:
MediaInfo author is informed, see: https://github.com/MediaArea/MediaInfoLib/issues/996
Will probably not get around to write a workaround for this today, but it's planned for tomorrow.

Cu Selur
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#4
So, what do I do? I need to convert these files ASAP.
Maybe install another program? Use MeGUI while the problem is not fixed?
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#5
Afaik MeGui won't work since last I checked it also used MediaInfo and unlike Hybrid won't fall back to MPlayer in case MediaInfo fails.

What you want to try is a tool which:
a. is based on ffmpeg/libav
b. is freshly build since even ffmpeg/libav didn't report such files properly a few month ago either.

Alternatively, what I probably would do if I needed this to be over with asap:
Convert the audio using ffmpeg into a format which is better supported, in example flac (which is lossless):
"F:\PROGRA~1\Hybrid\64bit\ffmpeg.exe" -y -threads 4 -i "F:\# Backup\#Pasta Downloads (iniciou 15.12.17)\Sonic Unleashed XBOX 360\PS2_MOV\SEGALOGO.mpg" -c:v copy -c:a flac "F:\# Backup\#Pasta Downloads (iniciou 15.12.17)\SEGALOGO_WITHFLACAUDIO.mkv"
and convert that output file with Hybrid. Smile

Cu Selur
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