Television loudness is the source of frustration for viewers +everywhere. Some channels are very load, others are less loud, and +ads tend to shout very high to get the attention of the viewers, and +the viewers do not like this. This fact is well known to the TV +channels. See for example the BBC white paper +"Terminology +for loudness and level dBTP, LU, and all that" from 2011 for a +summary of the problem domain. To better address the need for even +loadness, the TV channels got together several years ago to agree on a +new way to measure loudness in digital files as one step in +standardizing loudness. From this came the ITU-R standard BS.1770, +"Algorithms to +measure audio programme loudness and true-peak audio level".
+ +The ITU-R BS.1770 specification describe an algorithm to measure +loadness in LUFS (Loudness Units, referenced to Full Scale). But +having a way to measure is not enough. To get the same loudness +across TV channels, one also need to decide which value to standardize +on. For European TV channels, this was done in the EBU Recommondaton +R128, "Loudness +normalisation and permitted maximum level of audio signals", which +specifies a recommended level of -23 LUFS. In Norway, I have been +told that NRK, TV2, MTG and SBS have decided among themselves to +follow the R128 recommondation for playout from 2016-03-01.
+ +There are free software available to measure and adjust the loudness +level using the LUFS. In Debian, I am aware of a library named +libebur128 +able to measure the loudness and since yesterday morning a new binary +named bs1770gain +capable of both measuring and adjusting was uploaded and is waiting +for NEW processing. I plan to maintain the latter in Debian under the +Debian +multimedia umbrella.
+ +The free software based TV channel I am involved in, +Frikanalen, plan to follow the +R128 recommondation ourself as soon as we can adjust the software to +do so, and the bs1770gain tool seem like a good fit for that part of +the puzzle to measure loudness on new video uploaded to Frikanalen. +Personally, I plan to use bs1770gain to adjust the loudness of videos +I upload to Frikanalen on behalf of the +NUUG member organisation. The program seem to be able to measure +the LUFS value of any media file handled by ffmpeg, but I've only +successfully adjusted the LUFS value of WAV files. I suspect it +should be able to adjust it for all the formats handled by ffmpeg.
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