Loudness correction to EBU r128

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abul
Posts: 54
Joined: Wed Sep 11, 2019 12:45 pm

Loudness correction to EBU r128

Post by abul » Thu Nov 14, 2019 2:06 pm

Hi All,

I am trying to see if there is a way to do loudness correction to match EBU r128 standard.

I know under analysis there is a loudness node.

The output format has to be MXF.

I used XDCAM encoder and selected match audio to -23, however when using software like Eff to determine if audio needs correcting then corrects it, it states that the file has failed loudness test and does not match EBU r128

- Abul

admin
Site Admin
Posts: 1458
Joined: Sat Feb 08, 2014 10:39 pm

Re: Loudness correction to EBU r128

Post by admin » Thu Nov 14, 2019 4:17 pm

Hi Abul,

How have you configured your loudness workflow? If you could describ, supply some screenshots or export and post workflow itself it's easier to help.

-steinar

abul
Posts: 54
Joined: Wed Sep 11, 2019 12:45 pm

Re: Loudness correction to EBU r128

Post by abul » Thu Nov 14, 2019 4:39 pm

Hi Steinar,

I have attached my workflow.

-Abul
Attachments
Loudness.xml
(10.5 KiB) Downloaded 76 times

admin
Site Admin
Posts: 1458
Joined: Sat Feb 08, 2014 10:39 pm

Re: Loudness correction to EBU r128

Post by admin » Thu Nov 14, 2019 5:19 pm

Thanks abul. Your workflow looks ok.

I see you have chosen to measure stereo pairs in the "Loudness"-analyzer, which off course would be quite normal. But what does Eff measure, is it the two mono channels as one stereo pair or two independent channels? Do you have any output reports from Eff?

-steinar

abul
Posts: 54
Joined: Wed Sep 11, 2019 12:45 pm

Re: Loudness correction to EBU r128

Post by abul » Thu Nov 14, 2019 5:27 pm

File Information
File Size: 5927029863 bytes
Audio Duration: 900.8 seconds
Sample Rate: 48000 Hz
Num Channels: 2
Bits Per Sample: 24
Analysis Time: 97.0 seconds
Analysis Speed: 9 x
Correction Time: 30.2 seconds
Correction Speed: 30 x
Channel Group Information
Number of Groups: 2
Channel Group Layout: Mono_Mono
Channel Group Name: MonoOne
Loudness Specification: EBU R128
Loudness Units: LUFS
Program Loudness Target: -23.0 LUFS
Program Loudness: -27.3 LUFS
Loudness Range: 8
PPM Scale: BBC
PPM Threshold: 8.00
Max PPM: 7.74
True Peak Threshold: -3.00 dBTP
Maximum True Peak: -2.14 dBTP
Attenuation required for file to meet target: 4.3
Channel Group Name: MonoTwo
Loudness Specification: EBU R128
Loudness Units: LUFS
Program Loudness Target: -23.0 LUFS
Program Loudness: -27.3 LUFS
Loudness Range: 8
PPM Scale: BBC
PPM Threshold: 8.00
Max PPM: 7.83
True Peak Threshold: -3.00 dBTP
Maximum True Peak: -1.97 dBTP
Attenuation required for file to meet target: 4.3
1




The above is eff response

admin
Site Admin
Posts: 1458
Joined: Sat Feb 08, 2014 10:39 pm

Re: Loudness correction to EBU r128

Post by admin » Thu Nov 14, 2019 5:52 pm

Ok, so you need to make sure that:

- The two channels are measured as a stereo pair, and not two mono which is what I read from the Eff output.
OR
- You need to change the analyzer to analyze mono with channel looping.

Please change either and report back.

-steinar

abul
Posts: 54
Joined: Wed Sep 11, 2019 12:45 pm

Re: Loudness correction to EBU r128

Post by abul » Thu Nov 14, 2019 7:23 pm

File Information
File Size: 273900125 bytes
Audio Duration: 39.9 seconds
Sample Rate: 48000 Hz
Num Channels: 4
Bits Per Sample: 24
Analysis Time: 6.9 seconds
Analysis Speed: 6 x
Correction Time: 1.2 seconds
Correction Speed: 32 x
Channel Group Information
Number of Groups: 4
Channel Group Layout: Mono_Mono_Mono_Mono
Channel Group Name: MonoOne
Loudness Specification: EBU R128
Loudness Units: LUFS
Program Loudness Target: -23.0 LUFS
Program Loudness: -26.0 LUFS
Loudness Range: 7
PPM Scale: BBC
PPM Threshold: 8.00
Max PPM: 6.32
True Peak Threshold: -3.00 dBTP
Maximum True Peak: -7.71 dBTP
Attenuation required for file to meet target: 3.0
Channel Group Name: MonoTwo
Loudness Specification: EBU R128
Loudness Units: LUFS
Program Loudness Target: -23.0 LUFS
Program Loudness: -26.0 LUFS
Loudness Range: 8
PPM Scale: BBC
PPM Threshold: 8.00
Max PPM: 6.34
True Peak Threshold: -3.00 dBTP
Maximum True Peak: -7.73 dBTP
Attenuation required for file to meet target: 3.0
Channel Group Name: MonoThree
Loudness Specification: EBU R128
Loudness Units: LUFS
Program Loudness Target: -23.0 LUFS
Program Loudness: -100.0 LUFS
1
Loudness Range: -100
PPM Scale: BBC
PPM Threshold: 8.00
Max PPM: 0.00
True Peak Threshold: -3.00 dBTP
Maximum True Peak: -inf dBTP
Attenuation required for file to meet target: 0.0
Channel Group Name: MonoFour
Loudness Specification: EBU R128
Loudness Units: LUFS
Program Loudness Target: -23.0 LUFS
Program Loudness: -100.0 LUFS
Loudness Range: -100
PPM Scale: BBC
PPM Threshold: 8.00
Max PPM: 0.00
True Peak Threshold: -3.00 dBTP
Maximum True Peak: -inf dBTP
Attenuation required for file to meet target: 0.0
2



doing that caused it to get 4 channels rather than


***EDIT:

Ignore the above. i did 1 mono on loop and file passed :D
Selected the wrong option before :@

admin
Site Admin
Posts: 1458
Joined: Sat Feb 08, 2014 10:39 pm

Re: Loudness correction to EBU r128

Post by admin » Thu Nov 14, 2019 7:38 pm

Ok, I'm not sure what's going on with Eff, don't know the program....

Could you import the attached workflow and manually submit some files to the first loudness node, and then see what the outcome in the status monitor is? On each file you should see two different results in the form: "[-dB, -dB]", where one is the original -dB and the other is the new -23 (+/- 0.5).

-steinar
Attachments
Loudness-2 test.xml
(8.82 KiB) Downloaded 76 times

abul
Posts: 54
Joined: Wed Sep 11, 2019 12:45 pm

Re: Loudness correction to EBU r128

Post by abul » Fri Nov 15, 2019 9:32 am

It working now, I get the report its passed eFF.

Just a quick question, if I want to do the loudness on an MXF file, is there a way to pass it through XDCAM without it encoding again but adding the volume control. for example the options none, transwrap or wrap when possible?

abul
Posts: 54
Joined: Wed Sep 11, 2019 12:45 pm

Re: Loudness correction to EBU r128

Post by abul » Fri Nov 15, 2019 9:46 am

I want to be able to apply the loudness filter on mxf files as well, however, I don't want to reencode as they are over 6GB and takes time to encode

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