In a previous blogpost we talked about the Opus codec, which offers very low bitrates. Another codec seeking to achieve even lower bitrates is Codec 2.

Codec 2 is designed for use with speech only, and although the bitrates are impressive the results aren’t as clear as Opus, as you can hear in the following audio examples. However, there is some interesting work being done with Codec 2 in combination with neural network (WaveNets) that is yielding great results.

Layers of a WaveNet neural network.

Background

Codec 2 is an open source codec designed for ...

A few days ago a discussion in the Freak Show podcast pointed to an interesting BBC research project to render audio waveforms in the browser.
We now added a new output file format (Waveform Data File), which is generated by the open source tool audiowaveform and can be used to display interactive audio waveform data using the Peaks.js java script library. Here is an example screenshot:

(image from BBC R&D blog)

The tool includes features to zoom in waveforms, to mark segments in audio files (could be interesting for chapter marks) and can be easily integrated ...

We are very happy that Opus, an exciting new open audio codec, is now officially standardized by the Internet Engineering Task Force (IETF). Opus is particularly interesting for podcasts, radio books and internet audio in general due to its suitability for both, music and speech, and its outstanding sound quality at also very low bitrates.
In this article, we will listen to some examples of the Opus codec in action and have a closer look at the codec and how audio producers can benefit from it.

Why Opus?

Opus is a lossy audio codec that has ...

This is the first entry out of a series of posts, where I compare various aspects of popular podcasts. Part 1 is about file formats, bitrates, samplerates, channels, size, length and filenames.

The selection is based on Flattr podcast charts (mostly german), iTunes Store Top 10 Podcasts (english, german), podcasts by public radios (english, german) and some random ones to get more diversity.

List of Analyzed Podcasts

Here is the list of podcasts with links to the analyzed episodes, the available file formats and filenames (only for one format):

Many different audio file formats exist for storing recorded audio data on a computer system. This post compares multiple file types and gives suggestions on which formats and bitrates one should use, especially when producing podcasts or other online audio.

We also added two listening examples to compare MP3, AAC and Opus files at various bitrates.

If you just want to see some practical tips, skip the description and read the conclusion.

UPDATE 2017:
The original article was updated to include the new Opus audio codec, concrete bitrate suggestions, audio examples at various bitrates and other recent developments!

Types ...