Greetings!
I am using exiftool v11.99 on windows 7.
There are m4a files on the Internet where there is the line "Real-time streaming protocol", in metadata.
How can I delete this line via exiftool?
In these files also, if we look at the information through the mediainfo, we will find two additional sections: "Other #1 with Type: Object description" and "Other #2 with Type: Scene description".
How delete sections: "Other #1" and "Other #2" via exiftool?
First, find the names of the tags by running
exiftool -s /path/to/files/
After you find the names of the tags you want to delete, run this, replacing TAG* with the names of the tags
exiftool -TAG= -TAG1= -TAG2= /path/to/files/
But take note that this data may be custom tags which exiftool doesn't have a definition for, so it may not be able to delete them. In that case, you'll probably have to turn to ffmpeg. In that case, see this answer (https://askubuntu.com/a/195346/445931). While that talks about converting from MKV to M4V, the process is the same.
Thank you for responding.
I tried exiftool -s / path / to / files / and did not see the tag information.
I did this: exiftool input.m4a
to see all the metadata file information. I am attaching an example metadata list:
File Type : MP4
File Type Extension : mp4
MIME Type : video/mp4
Major Brand : MP4 v2 [ISO 14496-14]
Minor Version : 0.0.0
Compatible Brands : mp42, isom
Movie Header Version : 0
Create Date : 2019:03:15 11:08:30
Modify Date : 2019:03:15 11:13:50
Time Scale : 48000
Duration : 2:01:02
Preferred Rate : 1
Preferred Volume : 100.00%
Preview Time : 0 s
Preview Duration : 0 s
Poster Time : 0 s
Selection Time : 0 s
Selection Duration : 0 s
Current Time : 0 s
Next Track ID : 4
Track Header Version : 0
Track Create Date : 2019:03:15 11:08:30
Track Modify Date : 2019:03:15 11:13:50
Track ID : 1
Track Duration : 2:01:02
Track Layer : 0
Track Volume : 100.00%
Balance : 0
Audio Format : mp4a
Audio Channels : 2
Audio Bits Per Sample : 16
Audio Sample Rate : 48000
Handler Vendor ID : Apple
iTunSMPB : 0 640 1C0 151F0800 0 0 0 0 0 0 0 0
Encoder : fhgaac ;VBR=6
Realtime Streaming Protocol : (SDP) a=isma-compliance:1,1.0,1..a=mpeg4-iod: "data:application/mpeg4-iod;ba
se64,AoCAghMAT///D///A4CAgSQAAkCAZGF0YTphcHBsaWNhdGlvbi9tcGVnNC1vZC1hdTtiYXNlNjQsQVlDQWdEOEJnSUNBT2dLZkE0Q0FnR
E1BQVFBRWdJQ0FGa0FWQUFsbkFBclVZQUFIWjBrRmdJQ0FCQkd3N1VBR2dJQ0FFQUJFQUFBQUFBQUFBQUFBQUFBQUFBTT0EgICADQEFAABEAAA
AAAAAAAAGgICACQEAAAAAAAAAAAOAgIBeAANAMmRhdGE6YXBwbGljYXRpb24vbXBlZzQtYmlmcy1hdTtiYXNlNjQsd0JBU2dUQXFCVzNBBICAg
BUCDQAACQAAAAAAAAAABYCAgAMAAGAGgICACQEAAAAAAAAAAA=="..
Elementary Stream Track : 3
Matrix Structure : 1 0 0 0 1 0 0 0 1
Media Header Version : 0
Media Create Date : 2019:03:15 11:13:50
Media Modify Date : 2019:03:15 11:13:50
Media Time Scale : 1000
Media Duration : 2:01:02
Handler Type : Scene Description
Other Format : mp4s
Media Data Size : 28
Media Data Offset : 449154431
Avg Bitrate : 485 kbps
There is a line with the name: "Realtime Streaming Protocol :" What is the name of the tag for this line?
I tried the command: exiftool -all = input.m4a. The command works, but does not delete the line "Real-time streaming protocol:"
If we open the file through media information, we see information about the stream "Audio # 1" with "ID : 1", and below we see two additional sections of information: "Other # 1" and "Other # 2". Here is an example:
Other #1
ID : 2
Type : Object description
Format : System
Codec ID : mp4s-01
Duration : 2 h 1 min
Language : English
Encoded date : UTC 2019-03-15 11:13:50
Tagged date : UTC 2019-03-15 11:13:50
Other #2
ID : 3
Type : Scene description
Format : System Core
Codec ID : mp4s-02
Duration : 2 h 1 min
Language : English
Encoded date : UTC 2019-03-15 11:13:50
Tagged date : UTC 2019-03-15 11:13:50
What is the name of this tags: "Other # 1" and "Other # 2" ?
Quote from: Maxver on May 25, 2020, 07:53:21 AM
There is a line with the name: "Realtime Streaming Protocol :" What is the name of the tag for this line?
Use the
-s option to see the tag name.
But RealtimeStreamingProtocol is not currently writable (see the QuickTime tags documentation (https://exiftool.org/TagNames/QuickTime.html#HintInfo)).
- Phil
Quote from: Phil Harvey on May 25, 2020, 09:31:29 AM
But RealtimeStreamingProtocol is not currently writable (see the QuickTime tags documentation (https://exiftool.org/TagNames/QuickTime.html#HintInfo)).
Thanks for the link
That's right, there says it's not for the Writable.
I understand what the matter is. An example metadata file that I attached was created by another console encoder: "FhG AAC Encoder". This feature this encoder.
In the table "Realtime streaming protocol" identifity with Tag ID: 'rtp'
Exiftool understands this tag: 'rtp' ?
Also i find in table ['sdsm' = Scene Description] and ['odsm' = Object Descriptor] from section "QuickTime Handler Tags" .
Tag Name : "HandlerType" identify "Index1: 8"
Exiftool currently understands "QuickTime Handler Tags"?
The link I posted lists all of the QuickTime tags that ExifTool understands.
- Phil
I tried like this:
exiftool -TAG= "'-rtp'=" /path/to/file/
and received "Warning: Tag 'TAG' is not defined"
I don't understand where the mistake was made.
Please tell, how to write the 'rtp' removal tag correctly
Quote from: Phil Harvey on May 25, 2020, 09:31:29 AM
But RealtimeStreamingProtocol is not currently writable (see the QuickTime tags documentation (https://exiftool.org/TagNames/QuickTime.html#HintInfo)).
This means exiftool cannot edit/delete this tag. You'll have to look into some other software to remove it. Possibly ffmpeg.
Quote from: StarGeek on May 25, 2020, 01:23:14 PM
This means exiftool cannot edit/delete this tag. You'll have to look into some other software to remove it. Possibly ffmpeg.
I don't like how ffmpeg deletes metadata in m4a files. It automatically changes the flag to other parameters.
For example, parameter: bitrate! If the bitrate was "Variable", then after ffmpeg delete metadata, it will be displayed as "Constant".
This is wrong behavior.
The second reason - ffmpeg do it slower.
Please add the ability to remove these three tags in a next build of the exiftool.
Don't recompress, just remux. It will take the same amount of time as if you copied it.
ffmpeg -i Input.mp4 -map 0 -map_metadata -1 -c copy Output.mp4
-c copy tells ffmpeg to copy streams, not recompress
-map 0 tells it to copy all streams, not just the first one. Useful in case there is more than one audio/subtitle stream
-map_metadata -1 removes all metadata
From this SuperUser answer (https://superuser.com/a/1189314/314998)
Thanks for the answer.
I tried this option like this:
ffmpeg -i input.m4a -map_metadata -1 -c copy Output.m4a
This command is working.
But there is one drawback: after this operation in mediainfo we see "Bitrate mode: Constant".
But it should be like this: "Bitrate mode: Variable", because in the source file it was: Variable.
I noticed that this happens all the time when using ffmpeg with the key "-map_metadata -1" to delete metadata in single m4a files.
If we use the exiftool to delete / edit tags in single m4a files, the line "Bitrate mode: Variable" always remains unchanged. As it should be.
I would like to be able to delete the metadata through the Exiftool. She is better at this task. 8)
Please add new three tags in the next build.