Create high quality audio for the web
Encoding audio usually takes two forms, encoding audio along with video and encoding audio alone.
Just like the containers and codecs we discussed in our Video Encoding article, audio container files can also contain various audio codec formats. Standard container formats for audio are .MOV, .MP4, .Ogg and .WebM. Some of the standard codec formats are AAC, Vorbis and MP3.
Humans can generally perceive audio discrepancies better than visual ones. The history of this can be traced to early hand turned cinema projectors. The variable speed of a hand-cranked projectors made for an inadequate experience when audio was added to film because of the sensitivity we have to changes in audio.
Keeping this in mind we want to ensure that our audio quality remains constant even if our video quality drops from compression.
We have received some great help from the folks at lynda.com for creating high-quality audio for interviews and tutorials.
THE REAL WORLD EXAMPLE SHOWN BELOW ARE FOR THE SETTINGS USED FOR LYNDA.COM VIDEOS
This is a great setting for high-quality audio.
The Adobe Media Encoder has a number of presets that are great for encoding audio only files for use on in your websites. We take a look at some of these in the video above.
In the video below we'll take a look at the whole process with a real world example.
|Host||Quality||Audio Codec||B/R||Sample Rate|
|Vimeo||4:3 - SD||AAC-LC||320||48khz|
|Vimeo||16:9 - SD||AAC-LC||320||48khz|
|YouTube||360p||AAC-LC||384||96 or 48 khz|
|YouTube||480p||AAC-LC||384||96 or 48 khz|
|YouTube||720p||AAC-LC||384||96 or 48 khz|
|YouTube||1080p||AAC-LC||384||96 or 48 khz|
|YouTube||YouTube 1440p 2K||AAC-LC||384||96 or 48 khz|
|YouTube||YouTube 2160p 4K||AAC-LC||384||96 or 48 khz|