MeGUI: General Questions and Troubleshooting Thread

[tebasuna51]

@leon

I can't reproduce your problem:

--[Information] [30/07/2014 10:42:44] Trying to open the file with Import()
--[Information] [30/07/2014 10:42:47] Successfully opened the file with Import()
--[Information] [30/07/2014 10:42:54] ignoring downmix as there is only 2 channel
--[Information] [30/07/2014 10:42:54] Avisynth script
---[NoImage] Import("D:\test.avs")
---[NoImage] # detected channels: 2 channels
---[NoImage] # detected channel positions:
---[NoImage] SSRC(96000)
---[NoImage] Normalize()
...

The avs:

LoadPlugin("D:\Programa\megui\tools\ffms\ffms2.dll")
FFAudioSource("D:\test.mp4")

Mediainfo:

Audio
ID : 2
Format : AAC
Format/Info : Advanced Audio Codec
Format profile : HE-AACv2 / HE-AAC / LC
Codec ID : 40
Duration : 20s 153ms
Bit rate mode : Variable
Bit rate : 64.0 Kbps
Maximum bit rate : 68.4 Kbps
Channel(s) : 2 channels / 1 channel / 1 channel
Channel positions : Front: L R / Front: C / Front: C
Sampling rate : 44.1 KHz / 44.1 KHz / 22.05 KHz

Maybe your audio have some problem to be recognized properly like SBR-PS (high frequencies in SBR part, second channel in PS part).
Please put a sample.

BTW I can't understand your upsample to 96 KHz (SSRC)

[hello_hello]

It seems to happen (sometimes) if the input audio is mono. I tried converting a mono flac file and that was fine, but a mono m4a file containing AAC produced a similar warning. The output file was stereo (dual mono). It seems under some circumstances, mono audio is decoded to stereo, hence the warning. At least that's how it appears. I'm not sure it's anything to worry about unless you particularly want a single channel output.

leon's MediaInfo report..... I don't know whether that'd be the input or the output file or why it reports Channel(s) and Channel(s)_Original. He wasn't terribly specific.

--[Information] [31/07/14 3:57:58 AM] Trying to open the file with NicAudio
--[Information] [31/07/14 3:57:58 AM] Failed opening the file with NicAudio()
--[Information] [31/07/14 3:57:58 AM] Trying to open the file with BassAudioSource()
--[Information] [31/07/14 3:58:01 AM] Successfully opened the file with BassAudioSource()
--[Warning] [31/07/14 3:58:03 AM] channel count mismatch! The input file is reporting 1 channels and the AviSynth script is reporting 2 channels
--[Information] [31/07/14 3:58:03 AM] Avisynth script
---[NoImage] ClearAutoloadDirs()
---[NoImage] AddAutoloadDir("C:\Program Files\MeGUI\tools\avs\plugins")
---[NoImage] LoadPlugin("C:\Program Files\MeGUI\tools\avisynth_plugin\BassAudio.dll")
---[NoImage] BassAudioSource("D:\test.m4a")
---[NoImage] # detected channels: 1 channel
---[NoImage] # detected channel positions: 1/0/0
---[NoImage] return last
--[Information] [31/07/14 3:58:03 AM] Commandline used: -ignorelength -q 0.5 -if - -of "{0}"
--[Information] [31/07/14 3:58:03 AM] Avisynth script environment opened
--[Information] [31/07/14 3:58:03 AM] Script loaded
--[Information] [31/07/14 3:58:03 AM] Output Decoder
---[Information] [31/07/14 3:58:03 AM] Channels: 2
---[Information] [31/07/14 3:58:03 AM] Bits per sample: 32
---[Information] [31/07/14 3:58:03 AM] Sample rate: 48000
--[Information] [31/07/14 3:58:03 AM] Job commandline: C:\Program Files\MeGUI\tools\eac3to\neroAacEnc.exe -ignorelength -q 0.5 -if - -of "D:\test_new.m4a"
--[Information] [31/07/14 3:58:03 AM] Process started
--[Information] [31/07/14 3:58:03 AM] Standard output stream
--[Information] [31/07/14 3:58:03 AM] Standard error stream
--[Information] [31/07/14 3:58:15 AM] MediaInfo
---[Information] [31/07/14 3:58:15 AM] File: D:\test_new.m4a
---[Information] General
----[Information] Format: MPEG-4
----[Information] FormatString: MPEG-4
----[Information] FileSize: 3241936
----[Information] PlayTime: 00:03:49.909
---[Information] Audio
----[Information] ID: 1
----[Information] StreamOrder: 0
----[Information] Format: AAC
----[Information] FormatProfile: LC
----[Information] FormatSettingsSBR: No (Explicit)
----[Information] FormatSettingsPS:
----[Information] SamplingRate: 48000
----[Information] SamplingRateString: 48.0 KHz
----[Information] Channels: 2
----[Information] ChannelsString: 2 channels
----[Information] ChannelPositionsString2: 2/0/0
----[Information] BitRateMode: VBR
----[Information] Delay:
----[Information] Title:
----[Information] Language:
----[Information] LanguageString:
----[Information] Default:
----[Information] DefaultString:
----[Information] Forced:
----[Information] ForcedString:
--[Information] [31/07/14 3:58:15 AM] Postprocessing
--[Information] [31/07/14 3:58:15 AM] Job completed

[leon]

@tebasuna51
Hi thank you for your help.
I think the original audio was mono and it's been upmixed but wrong.
in MeGUI log window detected channels is one but in the script it's 2 this applies to channel positions to.
if MeGUI loads what is in scripts so why they aren't match.
I finally converted the audio with "Xilisoft Video Converter" to WAVE 2 channels and then encoded it with QAAC.

[leon]

@hello_hello

Hi
it's the input (original) audio,the output reports channel as mono.
your detected channels and channel positions are correct but look at mine how could one detected channel be 2/0/0.
I use downmix to Dolby pro logic II maybe that's the problem.

[hello_hello]

Maybe I'm on the wrong track, but the info as to which channel is which is obviously saved as part of the audio stream (left, right, centre etc) so maybe it's possible for a mono channel to be configured as left and right rather than as centre only. That'd explain:

Channel(s) : 2 channels
Channel(s)_Original : 1 channel

in the MediaInfo report for the original file. If the output is reported as mono, maybe that's "correct" in respect to having the same number of channels?

The MeGUI log file.... before it tries to commence encoding, shows a MediaInfo report for the file. In my case it always includes this for a mono AAC input file (under MediaInfo/Audio):

[Information] Channels: 1
[Information] ChannelsString: 1 channel
[Information] ChannelPositionsString2: 1/0/0

For other formats such as MP3 the ChannelPositionsString2 field is empty. Does your input file look any different?

I'll confess I'm guessing, but there does seem to be some inconsistencies when I tested some encodes of a mono file. If the source was mka, MP3 or an ffaudiosource script, the output was mono with no warnings. The same AAC audio in an m4a and the log file included the channel mismatch warning, the decoder output as 2 channels and the output file was stereo. Which seems odd, as the MediaInfo report was the same as above each time. The difference there seems to be the decoder used. It was NicAudio for the mka, BassAudio for the m4a.

Anyway, sorry..... I guess the channel mismatch I'm seeing in the log file is caused by a different circumstance than yours, but maybe I've helped someone work out why it's happening....?

[LigH]

I recently had a discussion about the M4A header created by QAAC which may indeed be slightly confusing. According to QAAC's author, nu774, there is an obsolete flag which only reports if the audio is mono or stereo (similar to MPEG1 audio), but most software is supposed to ignore it, because the AAC audio stream "kernel" has own flags which are more modern and detailed, as useful as e.g. WAVEFORMATEXTENSIBLE or Dolby Digital AC3 channel flags, supporting multi-channel audio configurations. Here in the HydrogenAudio forum:

Originally Posted by nu774

mp4a.channelcount is intentionally set to either 1 or 2, since in the former spec (ISO 14496-12) only 1 or 2 was allowed. However, it seems that no such restriction present in the new spec (4th ed @2012-7-15). Therefore, maybe I should fix qaac to write actual number of channels.

On the other hand, I can say for sure that nothing in AudioSampleEntry (mp4a) matters and cannot be taken seriously.
For example, samplesize field (typically it is 16) is non-sense for AAC.
samplerate field is 16.16 fixed-point, so not enough to represent high samplerate such as 96kHz.
I don't understand why MediaInfo looks at it at all.

[leon]

Hi
MeGUI is good with 5.1 channel and it can detect channels ans channel positions.
with 2 channels most of the time can't detect positions.
and it's not good with mono but when I convert my audio to WAVE not matter 1,2 or 5.1 channel it works good.

[hello_hello]

Originally Posted by LigH

I recently had a discussion about the M4A header created by QAAC which may indeed be slightly confusing. According to QAAC's author, nu774, there is an obsolete flag which only reports if the audio is mono or stereo (similar to MPEG1 audio), but most software is supposed to ignore it, because the AAC audio stream "kernel" has own flags which are more modern and detailed, as useful as e.g. WAVEFORMATEXTENSIBLE or Dolby Digital AC3 channel flags, supporting multi-channel audio configurations.

I guess that explains the "oddness" displayed by MediaInfo I noticed recently. I generally use NeroAAC but I was running some comparison encodes (using foobar2000) and noticed MediaInfo reported a 5.1ch AAC stream encoded with QAAC as:

Channel(s) : 2 channels
Channel(s)_Original : 6 channels

For the record, QAAC isn't alone when it comes to the flags it writes. The Fraunhofer AAC encoders seem to do the same thing. fdkaac.exe and fhgaacenc.exe (the front end for the Fraunhofer AAC encoder which comes with Winamp).
NeroAAC is the odd one out. It's the only encoder for which the output file was reported as simply being 6 channel by MediaInfo.

After muxing with the video in an MKV though, MediaInfo just reports 6 channels for the audio regardless of the AAC encoder.

(fhgaacenc.exe sure is fast. At least 50% faster than the rest. VBR encoding).

Anyway, that's getting away from leon's problem a little, although he hasn't uploaded a sample......

Originally Posted by leon

Hi
MeGUI is good with 5.1 channel and it can detect channels ans channel positions.
with 2 channels most of the time can't detect positions.
and it's not good with mono but when I convert my audio to WAVE not matter 1,2 or 5.1 channel it works good.

I can't say I've ever experienced any channel count mismatches when converting stereo audio with MeGUI.

[leon]

I said before that I converted the audio to WAVE with Xilisoft then encoded it so I don't have a sample.
wait hopefully I just found another file like that.

Audio
ID                                       : 2
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : LC
Codec ID                                 : 40
Duration                                 : 1h 3mn
Bit rate mode                            : Constant
Bit rate                                 : 56.0 Kbps
Channel(s)                               : 2 channels
Channel(s)_Original                      : 1 channel
Channel positions                        : Front: C
Sampling rate                            : 44.1 KHz
Compression mode                         : Lossy
Stream size                              : 25.5 MiB (10%)

the whole file is big so I can't upload it. is there anyway that I can upload the audio only untouched?

[hello_hello]

You said the original audio is mono and the output audio is mono, and from what we've been able to tell so far "Channel(s) : 2 channels" as reported by MediaInfo is probably wrong and "Channel(s)_Original : 1 channel" is probably correct. MeGUI is letting you know via the log file that MediaInfo reports two channels, but according to the Avisynth output there's only one. Unfortunately MeGUI doesn't have an option to convert mono to stereo as such. Mind you I'm not sure if there's any advantage to doing so anyway.

You could try loading the MP4 directly into MeGUI's audio section and re-encoding the audio that way (it doesn't matter if it also contains video). Every time I do, MeGUI uses BassAudioSource(), and even if the audio is actually mono, the output ends up being stereo (I assume BassAudio decodes it to stereo?), which I gather is what you're wanting. Currently you're using FFAudioSource() which seems to decode mono as mono.
Hopefully with BassAudio you'll go from mono input to stereo output with no channel mismatch being reported at all. If you try it that way, please report back with the result.

There's possibly no point extracting the audio and uploading it, because if the channel mismatch is being caused by flags saved to the MP4 container, then after extracting the audio you'll probably just have a mono aac file. You could maybe try splitting off a small section of the whole MP4 with something like My MP4Box GUI for uploading. Or even try opening the MP4 with MKVMergeGUI and remuxing it as an MKV, then checking the MKV version with MediaInfo. If I'm correct, once it's remuxed as an MKV, MediaInfo will probably only report the audio as being mono, if that's what it is.

[leon]

The result of using BaseAudio:

Audio
ID                                       : 1
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : HE-AAC / LC
Codec ID                                 : 40
Duration                                 : 1h 3mn
Bit rate mode                            : Variable
Bit rate                                 : 78.8 Kbps
Maximum bit rate                         : 102 Kbps
Channel(s)                               : 2 channels
Channel positions                        : Front: L R
Sampling rate                            : 96.0 KHz / 48.0 KHz
Compression mode                         : Lossy
Stream size                              : 35.9 MiB (98%)
Encoded date                             : UTC 2014-08-02 11:18:13
Tagged date                              : UTC 2014-08-02 11:26:38

The result of using FFAduioSource:

Audio
ID                                       : 1
Format                                   : AAC
Format/Info                              : Advanced Audio Codec
Format profile                           : HE-AAC / LC
Codec ID                                 : 40
Duration                                 : 1h 3mn
Bit rate mode                            : Variable
Bit rate                                 : 82.2 Kbps
Maximum bit rate                         : 108 Kbps
Channel(s)                               : 1 channel
Channel positions                        : Front: C
Sampling rate                            : 96.0 KHz / 48.0 KHz
Compression mode                         : Lossy
Stream size                              : 37.4 MiB (98%)
Encoded date                             : UTC 2014-08-02 11:30:17
Tagged date                              : UTC 2014-08-02 11:34:14

in this test FFAudioSource was 2x faster than BassAudioSource.(?)
I think MeGUI should use Channel(s)_Original value 1st.

[SacredCultivator]

I've noticed an error that's been happening often now but not too sure how to resolve.

-[Information] [8/2/2014 2:53:23 PM] Started handling job
-[Information] [8/2/2014 2:53:23 PM] Preprocessing
-[Information] [8/2/2014 2:53:23 PM] Avisynth input script
--[NoImage] #LoadPlugin("D:\Keepers\Subbing\VSFilterMod.dll")
--[NoImage] LoadPlugin("C:\Program Files (x86)\meGUI\tools\dgindex\DGDecode.dll")
--[NoImage] LoadPlugin("C:\Program Files (x86)\meGUI\tools\avisynth_plugin\ColorMatrix.dll")
--[NoImage] Load_Stdcall_Plugin("C:\Program Files (x86)\meGUI\tools\yadif\yadif.dll")
--[NoImage] DGDecode_mpeg2source("D:\Music\C-ute - Momoiro Sparkling (Close-up Ver.).d2v", info=3)
--[NoImage] ColorMatrix(hints=true, interlaced=true, threads=0)
--[NoImage] #Yadif(mode=1,order=1)
--[NoImage] #Yadif(order=1)
--[NoImage] #tfm(order=1).tdecimate(rate=23.976)
--[NoImage] #tfm(order=1).tdecimate(hybrid=1)
--[NoImage] TDecimate(cycleR=1)
--[NoImage] #Crop(left,top,right,bottom)
--[NoImage] Undot()
--[NoImage] Spline36Resize(720,480)
--[NoImage] global MeGUI_darx = 16
--[NoImage] global MeGUI_dary = 9
--[NoImage] #assumefps(23.976, 29.97, 59.94)
--[NoImage] AssumeFPS(24000, 1001)
--[NoImage] TextSubMod("D:\Music\C-ute - Momoiro Sparkling (Close-up Ver.).ass")
-[Information] [8/2/2014 2:53:26 PM] resolution: 720x480
-[Information] [8/2/2014 2:53:26 PM] frame rate: 24000/1001
-[Information] [8/2/2014 2:53:26 PM] aspect ratio: 16:9 (1.778)
-[Information] [8/2/2014 2:53:26 PM] Job commandline: "C:\Program Files (x86)\meGUI\tools\x264\x264.exe" --level 4.1 --crf 18.0 --keyint 230 --b-adapt 2 --ref 5 --vbv-bufsize 78125 --vbv-maxrate 62500 --rc-lookahead 50 --me umh --subme 11 --partitions all --trellis 2 --no-fast-pskip --sar 32:27 --output "D:\Music\C-ute - Momoiro Sparkling (Close-up Ver.) (H264).264" "D:\Music\C-ute - Momoiro Sparkling (Close-up Ver.) (H264).avs"
-[Information] [8/2/2014 2:53:26 PM] Process started
-[Information] [8/2/2014 2:53:26 PM] Standard output stream
-[Information] [8/2/2014 2:53:26 PM] Standard error stream
--[Information] [8/2/2014 2:53:29 PM] avs [info]: 720x480p 32:27 @ 24000/1001 fps (cfr)
--[Information] [8/2/2014 2:53:29 PM] x264 [info]: using SAR=32/27
--[Information] [8/2/2014 2:53:29 PM] x264 [info]: using cpu capabilities: MMX2 SSE2Fast SSSE3 SSE4.2 AVX XOP FMA4 FMA3 LZCNT BMI1
--[Information] [8/2/2014 2:53:29 PM] x264 [info]: profile High, level 4.1
-[Error] [8/2/2014 2:58:27 PM] Process exits with error: 0xC0000374 (-1073740940)
-[Information] [8/2/2014 2:58:27 PM] Job completed

For the error; Process exits with error: 0xC0000374 (-1073740940)
Before I used the 64-bit of x264 and it suggested to disable it, but even so, same error.

So not too sure what's causing it. And I can still mux the video, the issue before it seems to miss out on maybe .5/1 second at the end of the video.

[hello_hello]

Originally Posted by leon

in this test FFAudioSource was 2x faster than BassAudioSource.(?)

That's probably due to the fact the output is mono for FFAudioSource and it's easier to encode. As a quick experiment I converted a stereo MP3 to AAC (QAAC) with foobar2000. The first time it encoded at around 38x. The second time I got foobar2000 to downmix it to mono. Encoding speed was around 90x.

Originally Posted by leon

I think MeGUI should use Channel(s)_Original value 1st.

It seems like that'd make more sense, although it wouldn't give you a stereo output from a mono file. You just wouldn't have a channel mismatch warning in the log file.

[leon]

http://www.mediafire.com/download/aj9a9wkatdl1zet/1.mp4

This is a sample of that file and I split it as you said.

[hello_hello]

I'm getting the same result as you now.
FFAudioSource, mono input, mono output, channel mismatch warning in the log file.
BassAudioSource, mono input, stereo output, no channel mismatch warning.

In the end, I guess the problem is MediaInfo reports the info in the obsolete MP4 flags to MeGUI but it's no big deal given it doesn't stop MeGUI re-encoding it.

It's interesting BassAudioSource outputs stereo when the source is mono. I wasn't aware it did that. I wonder if it's by design?

[leon]

if it's by design so there is no way you can give a mono audio to encoder and have a mono output!!!
I'm not sure the problem is MediaInfo cause the video's been ripped from DVD and it suppose to be stereo.
or maybe I'm wrong and it's been encoded this way.I think the original channels was 2 and MediaInfo reports it as 1 and it's wrong.

[hello_hello]

The sample you uploaded is definitely mono. There's only a single audio channel. It's not especially uncommon for DVD audio to be mono, at least when it comes to old movies which had mono audio originally. Sometimes it's "dual mono" (ie stereo) but sometimes it's just mono. Even Bluray audio can be mono (mostly old movies, once again). Much like the audio for which someone posted a MediaInfo report here.

[leon]

yes the sample was mono but I'm sure that it originally was stereo and it isn't old movie.
I had a question too:
my speaker has 1 left 1 right and 1 center (only bass not sound) channels.my question is that what channel settings is best for it in encoders?
and what is Channel : 2\0x3?

[Kurtnoise]

@Leon : your mp4 sample is from the original track or from the transcode one ?

You should upload a sample from the original track...

btw, I've a patch for MediaInfo library when there is a mismatch between the Channels Count and the Channels Position.

[hello_hello]

Originally Posted by leon

my speaker has 1 left 1 right and 1 center (only bass not sound) channels.my question is that what channel settings is best for it in encoders?
and what is Channel : 2\0x3?

You have stereo speakers with a subwoofer?
My setup is the same. I don't there's any best encoder settings as such. If the audio is multi-channel I either keep the original or re-encode it as multi-channel. You never know, one day I might change my mind and decide surround sound doesn't completely suck. It gets downmixed to stereo on playback anyway (or it should be).
I guess if you're trying to keep the file size as small as possible then downmixing to stereo would be the way to go. It's all personal preference.

Channel : 2\0x3? I've no idea. Maybe it's just some oddness in respect to what MediaInfo is displaying.