Contents 1 Introduction.................................................................................................................................................. 1 2 Supported Codecs and Formats................................................................................................................ 2 3 Summary of Codec Features and Applications.........................................................................................3 4 Terminology...............................................
back to contents 1 Introduction The Sonnox Fraunhofer Codec Toolbox is designed for real-time auditioning of audio signals by the Fraunhofer codecs, in addition to offline decoding, encoding and metadata editing of the resulting files. Mixing engineers can produce compensated mixes optimised towards specific target codecs, thereby ensuring maximum fidelity.
back to contents 2 Supported Codecs and Formats Major codecs supported: • • • • • • MP3 AAC-LC HE-AAC HE-AAC v2 MPEG Surround Apple AAC (iTunes Plus; Mastered for iTunes) (Mac only) Formats supported: • • • Mono: MP3, AAC-LC, HE-AAC & HD-AAC Stereo: MP3, AAC-LC, HE-AAC, HE-AACv2 & HD-AAC, 5.
back to contents 3 Summary of Codec Features and Applications MP3 General purpose audio codec, compatible with most players. Typical bit rate: 128 kbps (stereo) AAC-LC (AAC Low Complexity) High performance audio codec for excellent audio quality at low bit rates. Used for ISDB television (Japan). Typical bit rate: 128 kbps (stereo) HE-AAC (High Efficiency AAC) High performance audio codec for good quality at bit rates of 32–48 kbps per channel.
back to contents 4 Terminology Bit rate Number of bits transmitted or processed per unit of time. This is expressed here in kilobits per second, or kbps. CBR Constant Bit Rate – bit rate remains the same for the duration of the audio signal VBR Variable Bit Rate – bit rate changes over time, based on the complexity of the signal. In this case, the VBR value expressed is an average over the length of the file.
back to contents 5 Codec Details Apple AAC iTunes Plus (Mastered for iTunes) (Mac only) The addition of the Apple AAC codec allows real-time audition of files produced under the Mastered for iTunes initiative that are destined for the iTunes store. This codec is available for Mac computers only. It uses the same Apple codecs and re-samplers that are used for the current iTunes Catalogue. It very specifically re-samples to 44.
back to contents 6 The Codec Toolbox Plug-In The primary purpose of the Codec Toolbox Plug-In is to provide a way of monitoring your host session material using the highly regarded Fraunhofer encoders, without the need for offline processing. By auditioning and comparing codecs in real-time, the plug-in enables you to make executive decisions about the most appropriate codecs to use. 1.
back to contents 2. Click inside the CODEC SELECTOR to reveal the codecs, modes and bit rates available for the current sample rate and plug-in channel configuration. This allows fast selection of different codec/setting combinations. • • • • The default codec settings are AAC-LC, 256 kbps, CBR (Constant Bit Rate). Selected codec settings are immediately reflected in the auditioned audio signal. Double-click a codec, mode or bit rate, or move the mouse cursor outside of the selector to close the window.
back to contents 6.1.1 NMR Meter The NMR METER (Noise to Mask Ratio) provides an indication of the frequency areas where the difference between the codec output and the original input might be audible. All lossy codecs will produce a very slightly different output from their input. The very nature of a perceptual coder is that this difference should be inaudible (i.e. masked by the output signal).
back to contents 6.1.2 Bit-stream OVERS Meter Any form of filtering can, under certain circumstances, increase the peak level of the signal. If your input is hot, this can potentially produce overloads when the signal is decoded. This effect can be very easily demonstrated with this plug-in. The bit-stream OVERS meter can be used to monitor this potential for overload. The post-decoder level is continually monitored, and the meter indicates levels over 0 dBFS.
back to contents 6.1.3 Channel Configuration In most DAW hosts, the Codec Toolbox plug-in can automatically detect the number of channels whether it is inserted on a mono, stereo or 5.1 surround track. Some hosts, however, have no method of passing channel configuration information to the plug-in, which subsequently defaults to a surround configuration.
back to contents 6.1.6 Internal Buffer Sizes For most codecs, the plug-in uses internal buffer sizes of 1024 samples for up to 48kHz operation and 2048 samples for 48kHz. We recommend that the buffer sizes of the sound card, and thus of the host application, are set to match these figures. Buffer sizes for the HE-AAC and HE-AAC v2 codecs are twice these figures (so 2048 samples for up to 48kHz operation).
back to contents When you have decided on suitable codec settings, and optimised your mix/master levels accordingly: 1. Bypass or disable the Codec Toolbox plug-in 2. Bounce to uncompressed WAV or AIFF and save the resulting file to your chosen folder. 3. Open the Codec Toolbox Manager. This can either be done by clicking the Manager icon at the top right of the plug-in, or by opening the application directly from disk.
back to contents 7 The Codec Toolbox Manager The Codec Toolbox Manager is an application, bundled with the Toolbox Plug-In, primarily intended for encoding files using the latest codec technology from Fraunhofer IIS. In addition, the Manager provides the ability to decode files, and features a metadata editor for adding metadata to your encoded files. This section provides an overview of the user interface, and discusses each section of the application in detail.
back to contents 5. Occupying the top right hand area of the screen is the Metadata Editor. If a supported M4A or MP3 file is selected, any metadata it contains can be examined, edited, and written back to the file. If a WAV or AIFF file is selected, the section is used to edit the metadata that will be written when this file is encoded. 7.1 Folder Browser The leftmost section of the Codec Toolbox Manager presents controls for browsing directories.
back to contents 7.1.2 Finding Audio Files on your System The Folder Browser includes a feature designed to help locate audio files on your system. Thus, using the built-in Folder Browser may be more efficient than browsing to directories using the operating-system pop-up browser (accessible via the Browse button at the top of the section). This feature works as follows: • • • Folders that contain audio files in any of their sub-folders are displayed with a full-colour blue folder icon.
back to contents 7.1.3 Supported File Types The Manager supports the following file types: • M4A AAC (including AAC-LC, HE-AAC and MPEG Surround) • MP3 • WAVE (Uncompressed) • AIFF (Uncompressed) Unsupported file types will not be recognised as audio files by the background scan process, nor will they be displayed in the File List (see next section). Click on a folder in the Browser to display the supported audio files it contains in the File List section. 7.
back to contents 7.2.1 Selecting Multiple Files – Batch Processing It is possible to select multiple files in the File List, for encoding/decoding to the same output format. To select multiple files: • • • Command+click (Mac) or control+click (Windows) to add a file to the current selection. Shift+click to select a range of files. Press command+A (Mac) or control+A (Windows) to select all.
back to contents 7.3 Encode-Decode Section This section occupies the lower-middle area of the Toolbox Manager window. It provides information about the selected file, Encoder settings or Decoder output format settings, output file name editing, and output file path selection. 1. Name of the selected file – If the file is not in the currently selected folder, click the Input File Name to reselect its parent folder in the Folder Browser. 2.
back to contents 6. Encode/Decode Button. If a WAV or AIFF file is selected, this button will be in ENCODE mode. If a supported M4A or MP3 file is selected, the button will be in DECODE mode. While an encode/decode operation is in progress, the button displays an internal progress bar; clicking the button will CANCEL the current encode/decode operation. 7.3.1 Encoding The CLIP SAFE button enables a level-correction feature.
back to contents 7.3.3 Decoding The Manager can also decode compressed files for import into a host sequencer (or for general purpose decoding). To decode supported M4A or MP3 files, simply select them in the File List, choose WAV or AIFF, and press the DECODE button. The Output file path panel also allows you to select where you would like the decoded files to be saved to. By selecting the ‘save to input folder’ option, the source folder will be used.
back to contents 7.5 The Metadata Editor This section describes the features and operation of the Manager’s Metadata Editor, which occupies the right hand side of the user interface. 7.5.1 Overview Many audio file formats, such as MP3 and M4A, can optionally contain information about a file. This information is commonly known as METADATA. Typical metadata tags in an audio file could include the Title, Artist, Track Number, and Cover Art. The Title tag of a file is distinct from its file name.
back to contents When an MP3 or M4A file is selected in the File List (single-click), any supported metadata it contains is imported into the Metadata Editor. Once a tag has been edited, its row is displayed with a light grey highlight. Metadata in files that are not currently selected can be previewed in context, by hovering the mouse cursor over the Metadata Import button in the File List. Undo/Redo Undo or Redo a metadata edit.
back to contents 7.5.2 Supported Tag Formats The Manager provides the ability to add and modify metadata in files with an ‘mp3’ extension, and some files with an ‘m4a’ extension. Adding and modifying metadata in m4a files compressed with the Apple Lossless Audio Codec (ALAC) is not supported. The Status panel will display an error message if one of these files is selected. The adding and editing of metadata in ‘wav’ and ‘aiff’ formats is not supported.
back to contents 7.5.3 Supported Tags The list of available tags varies between MP3 and AAC files due to the different metadata specifications of each format. Tags that are not supported for the selected file type will be disabled, and appear in italics.
back to contents 7.5.4 Editing Text Tags In order to edit a text tag, click on the tag row in the Metadata Editor. This opens an inline text field; type your changes into this field. There are two kind of text tag: • Single line • Multi-line (Lyrics and Comments) To accept changes for a single line tag, press the ENTER key, or press TAB or shift+TAB to accept and move to the next or previous tag. In multi-line tags, pressing ENTER will insert a new line into the tag text field.
back to contents 7.5.6 Importing Tags from Another File Any audio files that contain metadata are listed in the File List with a small arrow button in the rightmost column. Hover your mouse cursor over a button to PREVIEW the metadata from that file in the Metadata Editor. Click a button to IMPORT the metadata from that file into the Metadata Editor. Only non-empty tags will be imported, so existing edited tags cannot be overwritten with an empty tag from another file.
back to contents 7.5.7 Saving and Loading Metadata Presets Metadata tags can be saved into presets for later use. To display the metadata presets manager, click the PRESETS tab in the lower right hand area of the Manager. In this presets manager, a list of saved presets is displayed. Hover the mouse cursor over a preset name to preview the saved tags in the Metadata Editor. Click on a preset to load the saved tags into the Metadata Editor as changes for the selected file.
back to contents To save a new metadata preset, press command+S (Mac) or control+S (Windows), or press the PLUS button that appears on mouse over in the upper-left corner of the Preset Tab. This will open a text field where the preset name can be typed. Press Enter to save the preset, or Escape to dismiss the text field, and cancel the saving process. The list of presets is ordered alphabetically, and is immediately re-ordered when a new preset is saved.
back to contents 7.5.8 The Metadata Lock Mechanism It is important to remember that the changes performed in the Metadata Editor are not written to the selected file until the ‘Write to File’ button is pressed. If a new file is selected for processing when the metadata of the previously selected file has been edited (but not written-to-file), those changes will be lost. A pop-up window will appear in this case, to warn the user and allow the operation to be cancelled.
back to contents 8 Keyboard Shortcuts Global Context Process File(s) (encode or decode) Write metadata to selected file Undo metadata edit Redo metadata edit Save metadata preset Toggle playback Mac Command+P Command+W Command+Z Shift+cmd+Z Command+S Spacebar Windows Control+P Control+w Control+Z Shift+ctrl+Z Control+S Spacebar The grey highlight that appears around the Folder Browser, File List or Metadata Editor indicates the section that is currently the keyboard focus target for the remaining key co
back to contents 9 Workflow Example The first thing to do after launching the Codec Toolbox Manager, is load your uncompressed WAV/AIFF audio files. This can be done in one of three ways: 1. Browse to your folder using the built-in Folder Browser 2. Drag a folder from your operating system’s file browser onto the Manager 3. Drag one of your audio files onto the Manager Now, you should see your audio files listed in the Manager’s File List. **Single-click a file to select it for processing.
back to contents 10 10.1 Specifications Metadata Text Encoding Text encoding formats are a way of describing the internal byte representation of individual characters. The ID3 and iTunes metadata formats strictly define which text encodings are supported, so that any text tags (e.g. Title, Artist) can be read and written by different applications. This section describes how the Manager handles metadata text encoding for the different metadata formats supported by the Manager.
back to contents 10.2 Sample Rate and Bit Depth The Codec Toolbox plug-in and Manager support sample rates of 32, 44.1 and 48kHz. The input to the encoders will be dithered and truncated to 16 bits if necessary. If the signal has no activity below the 16th bit, the input to the encoders will not be dithered. 10.3 10.3.1 Codec Sample Rate vs. Bit Rate Sample Rate: 32 kHz MP3 – Mono CBR Bit rate (kbps) Codec Sample rate (kHz) VBR Bit rate (kbps) Codec Sample rate (kHz) 40 44.1 48 44.
back to contents MP3 – Stereo CBR Bit rate (kbps) Codec Sample rate (kHz) VBR Bit rate (kbps) Codec Sample rate (kHz) 80 44.1 112 32 128 44.1 130 44.1 160 44.1 150 44.1 192 44.1 190 44.1 224 44.1 220 44.1 256 44.1 320 44.1 AAC LC – Mono At all bit rates, the codec operates at 32 kHz – there is no resampling. AAC LC – Stereo At all bit rates, the codec operates at 32 kHz – there is no resampling. AAC LC – 5.
back to contents HE AAC V2 – Stereo At all bit rates, the codec operates at 32 kHz – there is no resampling. iTunes+ (Stereo only) CBR Bit rate (kbps) 10.3.2 Codec Sample rate (kHz) VBR Bit rate (kbps) Codec Sample rate (kHz) 256 44.1 VBR Bit rate (kbps) Codec Sample rate (kHz) Sample Rate: 44.1 kHz MP3 – Mono CBR Bit rate (kbps) Codec Sample rate (kHz) 56 32 64 44.1 78 44.1 80 44.1 84 44.1 96 44.1 88 44.1 112 44.1 112 44.1 128 44.1 128 44.1 160 44.1 192 44.1 224 44.
back to contents MP3 – Stereo CBR Bit rate (kbps) Codec Sample rate (kHz) VBR Bit rate (kbps) Codec Sample rate (kHz) 96 32 96 44.1 112 44.1 130 44.1 128 44.1 150 44.1 160 44.1 190 44.1 192 44.1 220 44.1 224 44.1 256 44.1 320 44.1 AAC LC – Mono At all bit rates, the codec operates at 44.1 kHz – there is no resampling. AAC LC – Stereo At all bit rates, the codec operates at 44.1 kHz – there is no resampling. AAC LC – 5.1 At all bit rates, the codec operates at 44.
back to contents HD AAC – Mono Audition not available. Plug-in output = input. HD AAC – Stereo CBR Bit rate (kbps) Codec Sample rate (kHz) 96 32 * 112 44.1 * 128 44.1 * 160 44.1 * 192 44.1 * 224 44.1 * 256 48 * VBR Bit rate (kbps) Codec Sample rate (kHz) * Audition not available. Plug-in output = input HD AAC – 5.1 Audition not available. Plug-in output = input. AAC LC MPS – 5.1 At all bit rates, the codec operates at 44.1 kHz – there is no resampling. HE AAC MPS – 5.
back to contents 10.3.3 Sample Rate: 48 kHz MP3 – Mono CBR Bit rate (kbps) Codec Sample rate (kHz) VBR Bit rate (kbps) Codec Sample rate (kHz) 56 32 64 32 80 32 84 32 96 32 88 32 112 32 112 32 128 32 128 32 160 32 192 32 224 32 256 32 320 32 VBR Bit rate (kbps) Codec Sample rate (kHz) MP3 – Stereo CBR Bit rate (kbps) Codec Sample rate (kHz) 112 44.1 128 44.1 130 44.1 160 44.1 150 44.1 192 44.1 190 44.1 224 44.1 220 44.1 256 44.
back to contents AAC LC – Mono At all bit rates, the codec operates at 48 kHz – there is no resampling. AAC LC – Stereo At all bit rates, the codec operates at 48 kHz – there is no resampling. AAC LC – 5.1 At all bit rates, the codec operates at 48 kHz – there is no resampling. HE AAC – Mono At all bit rates, the codec operates at 48 kHz – there is no resampling. HE AAC – Stereo At all bit rates, the codec operates at 48 kHz – there is no resampling. HE AAC – 5.
back to contents iTunes+ (Stereo only) CBR Bit rate (kbps) Codec Sample rate (kHz) VBR Bit rate (kbps) Codec Sample rate (kHz) 256 44.
back to contents 11 Copyright and Acknowledgements The Sonnox Fraunhofer Codec Toolbox plug-in and Manager were developed by the design team at Sonnox in collaboration with Fraunhofer IIS. The Audio Coding software contained in the Sonnox Fraunhofer Codec Toolbox plug-in and Manager was developed and provided by Fraunhofer IIS of Erlangen, Germany. Trademarks and content copyright 2007-Present Sonnox Ltd. All rights reserved. Fraunhofer IIS and related logos are registered trademarks.
back to contents 12 Commercial use of mp3 content It is important to distinguish between the use of codecs and the use of content produced by the codecs; and therefore it is important to note that any mp3 royalty fees are independent of which encoder is used to produce the mp3 file content. If royalty fees are due for a particular project or enterprise, they will be due irrespective of whether the Pro- Codec is used or some alternative encoder is used.
back to contents 13 • • • • • 14 Supported Platforms Avid Pro Tools (RTAS, AAX 64-bit) VST hosts (32 and 64-bit) AU hosts (32 and 64-bit) Mac Intel OSX 10.6 or higher Windows XP, 7 and 8 (32 and 64-bit) System Requirements For latest System requirements, please see www.sonnox.com Pro Tools • • • • • • Windows XP/7/8 or Apple Mac OSX 10.
