aac files from youtube - what is the difference? (ffmpeg -i)

4th Aug 2019 18:37 #1

Member

Hi.

Have some audio files (.aac) that is downloaded from youtube via an firefox extension.

There seems to be two types of aac files, based on the output from ffmpeg -i command.

Example 1 (most common)

Code:

ffmpeg -i 'Track 1.aac' -hide_banner
[aac @ 0x55a6ce64db00] Estimating duration from bitrate, this may be inaccurate
Input #0, aac, from 'Track 1.aac':
  Duration: 00:05:42.05, bitrate: 122 kb/s
    Stream #0:0: Audio: aac (LC), 44100 Hz, stereo, fltp, 122 kb/s
At least one output file must be specified

Example 2

Code:

ffmpeg -i 'Track 2.aac' -hide_banner
Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'Track 2.aac':
  Metadata:
    major_brand     : dash
    minor_version   : 0
    compatible_brands: iso6mp41
    creation_time   : 2018-09-17T20:30:35.000000Z
  Duration: 00:07:54.80, start: 0.000000, bitrate: 127 kb/s
    Stream #0:0(eng): Audio: aac (LC) (mp4a / 0x6134706D), 44100 Hz, stereo, fltp, 2 kb/s (default)
    Metadata:
      creation_time   : 2018-09-17T20:30:35.000000Z
      handler_name    : SoundHandler
At least one output file must be specified

It seems that one file have metadata while the other have none. Is there other differences?

Quote

4th Aug 2019 23:49 #2

El Heggunte

DECEASED

It seems to me "Track 2.aac" is actually an m4a or mp4 file with the wrong extension.
Try MediaInfo and tell us what it says.

"Programmers are human-shaped machines that transform alcohol into bugs."

Quote

5th Aug 2019 09:52 #3

Prototype v1.0

Member

I think that too.

Mediainfo for Track 1

Code:

<?xml version="1.0" encoding="UTF-8"?>
<MediaInfo
    xmlns="https://mediaarea.net/mediainfo"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="https://mediaarea.net/mediainfo https://mediaarea.net/mediainfo/mediainfo_2_0.xsd"
    version="2.0">
<creatingLibrary version="19.07" url="https://mediaarea.net/MediaInfo">MediaInfoLib</creatingLibrary>
<media ref="/home/prototype/Desktop/music/Track 1.aac">
<track type="General">
<AudioCount>1</AudioCount>
<FileExtension>aac</FileExtension>
<Format>ADTS</Format>
<FileSize>5258855</FileSize>
<OverallBitRate_Mode>VBR</OverallBitRate_Mode>
<StreamSize>0</StreamSize>
<File_Modified_Date>UTC 2018-11-01 17:14:29</File_Modified_Date>
<File_Modified_Date_Local>2018-11-01 18:14:29</File_Modified_Date_Local>
</track>
<track type="Audio">
<Format>AAC</Format>
<Format_Version>4</Format_Version>
<Format_AdditionalFeatures>LC</Format_AdditionalFeatures>
<CodecID>2</CodecID>
<BitRate_Mode>VBR</BitRate_Mode>
<Channels>2</Channels>
<ChannelPositions>Front: L R</ChannelPositions>
<ChannelLayout>L R</ChannelLayout>
<SamplesPerFrame>1024</SamplesPerFrame>
<SamplingRate>44100</SamplingRate>
<FrameRate>43.066</FrameRate>
<Compression_Mode>Lossy</Compression_Mode>
<StreamSize>5258855</StreamSize>
<StreamSize_Proportion>1.00000</StreamSize_Proportion>
</track>
</media>
</MediaInfo>

And for Track 2

Code:

<?xml version="1.0" encoding="UTF-8"?>
<MediaInfo
    xmlns="https://mediaarea.net/mediainfo"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="https://mediaarea.net/mediainfo https://mediaarea.net/mediainfo/mediainfo_2_0.xsd"
    version="2.0">
<creatingLibrary version="19.07" url="https://mediaarea.net/MediaInfo">MediaInfoLib</creatingLibrary>
<media ref="/home/prototype/Desktop/music/Track 2.aac">
<track type="General">
<AudioCount>1</AudioCount>
<FileExtension>aac</FileExtension>
<Format>dash</Format>
<CodecID>dash</CodecID>
<CodecID_Compatible>iso6/mp41</CodecID_Compatible>
<FileSize>7541674</FileSize>
<Duration>474.802</Duration>
<OverallBitRate>127071</OverallBitRate>
<StreamSize>87984</StreamSize>
<HeaderSize>3020</HeaderSize>
<DataSize>157378</DataSize>
<FooterSize>7381276</FooterSize>
<IsStreamable>Yes</IsStreamable>
<Encoded_Date>UTC 2018-09-17 20:30:35</Encoded_Date>
<Tagged_Date>UTC 2018-09-17 20:30:35</Tagged_Date>
<File_Modified_Date>UTC 2018-10-25 22:04:53</File_Modified_Date>
<File_Modified_Date_Local>2018-10-26 00:04:53</File_Modified_Date_Local>
</track>
<track type="Audio">
<StreamOrder>0</StreamOrder>
<ID>1</ID>
<Format>AAC</Format>
<Format_AdditionalFeatures>LC</Format_AdditionalFeatures>
<CodecID>mp4a-40-2</CodecID>
<Duration>474.802</Duration>
<BitRate>125588</BitRate>
<Channels>2</Channels>
<ChannelPositions>Front: L R</ChannelPositions>
<ChannelLayout>L R</ChannelLayout>
<SamplesPerFrame>1024</SamplesPerFrame>
<SamplingRate>44100</SamplingRate>
<SamplingCount>20938768</SamplingCount>
<FrameRate>43.066</FrameRate>
<FrameCount>20448</FrameCount>
<Compression_Mode>Lossy</Compression_Mode>
<StreamSize>7453690</StreamSize>
<StreamSize_Proportion>0.98833</StreamSize_Proportion>
<Language>en</Language>
<Encoded_Date>UTC 2018-09-17 20:30:35</Encoded_Date>
<Tagged_Date>UTC 2018-09-17 20:30:35</Tagged_Date>
</track>
</media>
</MediaInfo>

Quote

5th Aug 2019 10:27 #4

video.baba

Member

Originally Posted by Prototype v1.0

I think that too.

Mediainfo for Track 1

Code:

<?xml version="1.0" encoding="UTF-8"?>
<MediaInfo
    xmlns="https://mediaarea.net/mediainfo"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="https://mediaarea.net/mediainfo https://mediaarea.net/mediainfo/mediainfo_2_0.xsd"
    version="2.0">
<creatingLibrary version="19.07" url="https://mediaarea.net/MediaInfo">MediaInfoLib</creatingLibrary>
<media ref="/home/prototype/Desktop/music/Track 1.aac">
<track type="General">
<AudioCount>1</AudioCount>
<FileExtension>aac</FileExtension>
<Format>ADTS</Format>
<FileSize>5258855</FileSize>
<OverallBitRate_Mode>VBR</OverallBitRate_Mode>
<StreamSize>0</StreamSize>
<File_Modified_Date>UTC 2018-11-01 17:14:29</File_Modified_Date>
<File_Modified_Date_Local>2018-11-01 18:14:29</File_Modified_Date_Local>
</track>
<track type="Audio">
<Format>AAC</Format>
<Format_Version>4</Format_Version>
<Format_AdditionalFeatures>LC</Format_AdditionalFeatures>
<CodecID>2</CodecID>
<BitRate_Mode>VBR</BitRate_Mode>
<Channels>2</Channels>
<ChannelPositions>Front: L R</ChannelPositions>
<ChannelLayout>L R</ChannelLayout>
<SamplesPerFrame>1024</SamplesPerFrame>
<SamplingRate>44100</SamplingRate>
<FrameRate>43.066</FrameRate>
<Compression_Mode>Lossy</Compression_Mode>
<StreamSize>5258855</StreamSize>
<StreamSize_Proportion>1.00000</StreamSize_Proportion>
</track>
</media>
</MediaInfo>

And for Track 2

Code:

<?xml version="1.0" encoding="UTF-8"?>
<MediaInfo
    xmlns="https://mediaarea.net/mediainfo"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="https://mediaarea.net/mediainfo https://mediaarea.net/mediainfo/mediainfo_2_0.xsd"
    version="2.0">
<creatingLibrary version="19.07" url="https://mediaarea.net/MediaInfo">MediaInfoLib</creatingLibrary>
<media ref="/home/prototype/Desktop/music/Track 2.aac">
<track type="General">
<AudioCount>1</AudioCount>
<FileExtension>aac</FileExtension>
<Format>dash</Format>
<CodecID>dash</CodecID>
<CodecID_Compatible>iso6/mp41</CodecID_Compatible>
<FileSize>7541674</FileSize>
<Duration>474.802</Duration>
<OverallBitRate>127071</OverallBitRate>
<StreamSize>87984</StreamSize>
<HeaderSize>3020</HeaderSize>
<DataSize>157378</DataSize>
<FooterSize>7381276</FooterSize>
<IsStreamable>Yes</IsStreamable>
<Encoded_Date>UTC 2018-09-17 20:30:35</Encoded_Date>
<Tagged_Date>UTC 2018-09-17 20:30:35</Tagged_Date>
<File_Modified_Date>UTC 2018-10-25 22:04:53</File_Modified_Date>
<File_Modified_Date_Local>2018-10-26 00:04:53</File_Modified_Date_Local>
</track>
<track type="Audio">
<StreamOrder>0</StreamOrder>
<ID>1</ID>
<Format>AAC</Format>
<Format_AdditionalFeatures>LC</Format_AdditionalFeatures>
<CodecID>mp4a-40-2</CodecID>
<Duration>474.802</Duration>
<BitRate>125588</BitRate>
<Channels>2</Channels>
<ChannelPositions>Front: L R</ChannelPositions>
<ChannelLayout>L R</ChannelLayout>
<SamplesPerFrame>1024</SamplesPerFrame>
<SamplingRate>44100</SamplingRate>
<SamplingCount>20938768</SamplingCount>
<FrameRate>43.066</FrameRate>
<FrameCount>20448</FrameCount>
<Compression_Mode>Lossy</Compression_Mode>
<StreamSize>7453690</StreamSize>
<StreamSize_Proportion>0.98833</StreamSize_Proportion>
<Language>en</Language>
<Encoded_Date>UTC 2018-09-17 20:30:35</Encoded_Date>
<Tagged_Date>UTC 2018-09-17 20:30:35</Tagged_Date>
</track>
</media>
</MediaInfo>

You're joking right? Have you ever seen mediainfo output posted in the format you have? (please send me a link if you have). Why did you post it like that?

Quote

5th Aug 2019 11:39 #5

videobruger

Member

Use text mode in MediaInfo. Not xml.

Quote

5th Aug 2019 13:07 #6

Prototype v1.0

Member

I choosed xml because it is more detailed than text mode and I assumed that was the best (i.e. most informative) choice.

But hey, I can always post the text info in aditional:

Quote

5th Aug 2019 13:17 #7

Prototype v1.0

Member

Here it is:

Text version for track 1

Code:

General
Complete name                            : /home/prototype/Desktop/music/Track 1.aac
Format                                   : ADTS
Format/Info                              : Audio Data Transport Stream
File size                                : 5.02 MiB
Overall bit rate mode                    : Variable

Audio
Format                                   : AAC LC
Format/Info                              : Advanced Audio Codec Low Complexity
Format version                           : Version 4
Codec ID                                 : 2
Bit rate mode                            : Variable
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 44.1 kHz
Frame rate                               : 43.066 FPS (1024 SPF)
Compression mode                         : Lossy
Stream size                              : 5.02 MiB (100%)

Text version for track 2

Code:

General
Complete name                            : /home/prototype/Desktop/music/Track 2.aac
Format                                   : dash
Codec ID                                 : dash (iso6/mp41)
File size                                : 7.19 MiB
Duration                                 : 7 min 54 s
Overall bit rate                         : 127 kb/s
Encoded date                             : UTC 2018-09-17 20:30:35
Tagged date                              : UTC 2018-09-17 20:30:35

Audio
ID                                       : 1
Format                                   : AAC LC
Format/Info                              : Advanced Audio Codec Low Complexity
Codec ID                                 : mp4a-40-2
Duration                                 : 7 min 54 s
Bit rate                                 : 126 kb/s
Channel(s)                               : 2 channels
Channel layout                           : L R
Sampling rate                            : 44.1 kHz
Frame rate                               : 43.066 FPS (1024 SPF)
Compression mode                         : Lossy
Stream size                              : 7.11 MiB (99%)
Language                                 : English
Encoded date                             : UTC 2018-09-17 20:30:35
Tagged date                              : UTC 2018-09-17 20:30:35

Quote

5th Aug 2019 14:02 #8

pandy

Member

ADTS vs DASH

https://hydrogenaud.io/index.php/topic,107543.0.html

Quote

aac files from youtube - what is the difference? (ffmpeg -i)

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