User16987580801767947218 (no company) asked a question.
Is Dolby Atmos a lossless format only?
When subscribing to a streaming service that provides popular tv shows that when downloaded Mediainfo will reveal a lossy Dolby Digital + (EAC3) audio track that identifies as Atmos capable is this really Atmos?
When subscribing to a streaming service that provides popular tv shows that when downloaded Mediainfo will reveal a lossy Dolby Digital + (EAC3) audio track that identifies as Atmos capable is this really Atmos?
Appendix C in the Dolby Atmos training (available at learning.dolby.com) goes into detail on the different codecs used for Dolby Atmos delivery.
Briefly, Dolby Atmos streaming uses lossy codecs (DD+JOC and AC4-IMS) while blu-ray uses a lossless codec (TrueHD).
-B
have a question for you on the operation of the Dolby Media Encoder,
when one is encoding to either Eac3 or TrueHD, why does the completed Thd file not adhere to the Dolby Dialnorm setting of -27?
For whatever reason my finished audio file is considerably louder than its Eac3 counterpart.
When test encoding to both ....my dialnorm setting is -27 (Dolby default), the eac3 completes correctly at -27, one can see this in MediaInfo, but the TrueHd file will not.
The Truehd file appears to be dialnorm at -31 making it play 4 db louder thru my Onkyo Z series avr. Even if I test select at -23 the file IS still 4 db louder than the Eac3 file at -27.
Now if all consumer based AVR's with Dolby digital software included in them didn't look for the -27 as being the default then this wouldn't be an issue, the AVR would play the audio of everything at -31, but that's not the case. So the Dolby audio file has to have the proper metadata file indication that the file is dialnormed at -27 to play at the same volume as any other audio file format, but this isn't happening.
Suggestions?
thx.
Tony
Could you please share more details on the workflow you are working here.
First what Dolby Media Encoder you are using and what platform.
Second what is your input for Dolby Media Encoder, is it a Dolby Atmos Master File or is it some channel based content. Please note that Dolby loudness default value is "Measure". Please do youe encoding using recommended measure loudness setting and check then.
Other things to check are - what is your validation setup - are you validating Dolby Atmos outpus, or some low channel count like 5.1 or 2.0.
As far as I know AVRs are not able to identify and play back Dolby TrueHD files (mlp) since they have to authorised and prepared for BluRay Discs.
Have you tried to validate your encoded content using Dolby Reference Player and disable all DRC and check all the levels?
What are the values you are reffering to taken from?
Please note that if you find sharing those information confidential to share them here publicly you can contact us by case using details from Dolby Media Encoder Help -> Contact Dolby.