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Do you want to process huge amounts of audio or video files in one single step?
That's why we built the new Auphonic Batch Production Interface!
It allows you to start multiple productions with an existing Preset and can be used for file-based, automated batch processing of audio file collections.

UPDATE:
Please see Managed Processing of Audio and Video Archives for bigger datasets, customization and dedicated hardware.

Step 1: Select Preset and Files

First you have to select multiple input files and one preset. A preset stores common metadata, output file formats, outgoing file transfers and algorithm settings ...

We are very proud to release version one of the Auphonic audio post processing web API. This is a complete REST API to all our algorithms and functionality, for example:

This summer, we proudly released three important new features: video support, YouTube export for audio/video and the SoundCloud integration!
These features make it possible to use Auphonic for the automatic deployment of podcasts, screencasts, recordings, etc. to multiple platforms - see External Services.

The combination of SoundCloud and Auphonic provides a complete package for podcast post production, hosting, RSS feed generation and more.
Furthermore, the YouTube export function allows you to increase your audience through YouTube's content discovery mechanism, including listeners that you could not reach through a podcast RSS feed.


All file metadata, images and chapter marks ...

Have you ever wondered why commercials sound louder than your favorite TV shows? Or why you have to adjust the playback volume on your television when switching between channels? The answer is that until recently, there was no standard way to measure the perceived loudness of sound recordings. Instead, audio productions were (and still are) normalized to peak levels, which do in no way determine how loud a signal is.

In this article we will discuss the EBU recommendation R128, a new and open standard for balancing audio programs according to their actually perceived loudness.

EBU R128 logo

This recommendation marks ...

Because of so many requests we decided to release a preliminary version of our noise reduction algorithms. They are deactivated by default and you can activate them now in the production or preset form.
Additionally we included the possibility to enable or disable all auphonic audio algorithms :)

(poster from the movie Noise)

Current State of the Auphonic Noise Reduction Algorithms

The noise reduction algorithms are developed to remove constant background noise, hiss and hum in audio files with slowly varying backgrounds, such as lecture/conference recordings, static podcasts, etc.
They analyze the audio file, classify regions with different ...

For those who don't know it yet: we opened the auphonic automatic audio post production web service for the general public!
This means that everyone can create a free account and use the system for the post production of podcasts, audio books, lecture recordings, screencasts, or whatever you want. Please let us know what you think and tell us your feature requests!

Click here to create a free account:
Auphonic Registration

Current Audio Algorithms

Only a subset of the auphonic algorithms are activated at the moment, focusing on loudness and level management. Furthermore we filter unnecessary and disturbing frequencies, but ...

The last metadata format in this comparison series will be metadata for AAC audio files, which are usually included in an MP4 container (see MPEG-4 Part 14). MP4 audio files can have various file extensions, most commonly m4a, but also mp4 or m4b (for audio books).
So let the confusion continue ...

MP4, AAC and iTunes-style Metadata

The MPEG-4 container format is based on Apple's QuickTime container and each MPEG-4 file must have a major file brand. For example, an AAC audio file typically lists M4A as its major file brand. See AtomicParsley for a description of the ...

A new week - a new format: this weeks post is about metadata in Ogg Vorbis audio. The metadata container for these files is called Vorbis comment, which is also used in the FLAC, Theora and Speex file formats.
For a general introduction into audio metadata see e.g. the previous post in this comparison series: Part 2: MP3 Metadata (ID3 Tags).

The tool to analyze and create metadata for Ogg Vorbis files is called vorbiscomment.

About Vorbis Comment

Vorbis comment is a relatively simple metadata format specified by Xiph.org, similar to ID3 tags for MP3 ...

The second post of this comparison series is about metadata in MP3 files. Metadata allows information such as the title, artist, comments, cover image and other information about the audio to be stored in the file itself. MP3 files use ID3 tags and in the following I will compare common tags, image details and ID3 versions of various popular podcasts.
The analyzed files are the same as in Podcast Comparison, Part 1: File Formats and Bitrates.

Nice open source tools to analyze MP3 metadata are for instance eyeD3, soxi, mp3diags or EasyTag.

ID3 Versions and Used ...

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):

Podcast Filename of Episode File Formats
CRE 188 cre188-telecomix.mp3 MP3 ...