Contents 1 Introduction 5 2 Terminology 6 3 Supported Codecs and Formats 7 4 Summary of Codec Features and Applications 8 4.1 iTunes+ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.2 MPEG Surround . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.3 HD-AAC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.4 AAC-LC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.10 Description of Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Preset Manager Toolbar 43 53 6.1 Presets and Project/Session Data Handling . . . . . . . . . . . . . . . . . . . 54 6.1.1 Internal Data Rules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 6.2 Plug-In Signal and Control Flow Diagram . . . . . . . . . . . . . . . . . . . . 55 7 The Pro-Codec Manager Application 56 7.1 Folder Browser . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9 Specifications 74 9.1 Plug-In . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74 9.1.1 Delays and CPU Usage . . . . . . . . . . . . . . . . . . . . . . . . . . 74 9.1.2 Internal Buffer Sizes . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 9.1.3 GUI Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75 9.2 Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77 9.2.1 Metadata Text Encoding . . . . . .
1 1 INTRODUCTION Introduction In the past it has not been possible to critically audition and then encode multiple formats in real time within a host DAW environment. The revolutionary Sonnox Fraunhofer Pro-Codec Plug-In now makes this possible. The Pro-Codec Plug-In is designed for the real-time auditioning of audio signals by the Fraunhofer codecs. The Plug-In also provides the ability to record the real-time encoded data to disk (in the form of MP3 and M4A files).
2 2 TERMINOLOGY Terminology Bit rate This is the number of bits transmitted or processed per unit of time, expressed here in kilobits per second (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.
3 3 SUPPORTED CODECS AND FORMATS 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) Lossless Codecs Supported • HD-AAC (16/24 bits up to 192 kHz) Formats Supported Mono MP3, AAC-LC, HE-AAC and HD-AAC Stereo MP3, AAC-LC, HE-AAC, HE-AACv2 and HD-AAC, Apple AAC (iTunes Plus; Mastered for iTunes) (Mac only) 5.1 AAC-LC, HE-AAC and HD-AAC, MPEG Surround www.sonnox.
4 4 SUMMARY OF CODEC FEATURES AND APPLICATIONS 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.
4.1 4.1 iTunes+ 4 SUMMARY OF CODEC FEATURES AND APPLICATIONS Apple AAC – iTunes Plus (Mastered for iTunes) (Mac only) The addition of this 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 resamplers that are used for the current iTunes Catalogue. It very specifically resamples to 44.
4.3 HD-AAC 4.3 4 SUMMARY OF CODEC FEATURES AND APPLICATIONS HD-AAC (Fraunhofer) The HD-AAC codec from Fraunhofer has a very clever feature; the single compressed lossless file includes a lossy core channel. It therefore acts as a lossless archival format, a lossless distribution format for the masters, and a final playback format for both lossless and lossy decoders – and all of this in a single file.
5 5 5.1 THE PRO-CODEC PLUG-IN The Pro-Codec Plug-In User Interface and Workflow Overview The primary purpose of the Pro-Codec 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 Pro-Codec Plug-In allows you to make executive decisions about the best codecs to use.
5.1 User Interface and Workflow Overview 5 THE PRO-CODEC PLUG-IN FFT (Fast Fourier Transform) display INPUT Signal (yellow) NMR Indicator . DIFF Signal (red). DIFF Signal Red trace. This is the difference between the input and output signals. NMR Green/Red Trace. Noise to Mask Ratio is an indication of the audibility of codec-induced artefacts. See section 5.3.1 for more information. To ZOOM the display, Alt + drag (Mac and Windows).
5.1 User Interface and Workflow Overview 5 THE PRO-CODEC PLUG-IN Beneath the FFT/LISS display, the CODEC LIST enables the selection of up to five different codecs. Use the MON buttons to switch the real-time monitor path between the loaded codes. Use the ARM buttons to arm a codec for online (real-time) recording to an MP3 or M4A file. To the right of the codec list are three tabbed windows: BITSTREAM Level / TRIM – These meters show the decoded sample level for each codec. www.sonnox.
5.1 User Interface and Workflow Overview 5 THE PRO-CODEC PLUG-IN COMP – These meters show the data compression ratio for each codec. A-B (A-B-X) – This tab provides functions for A-B comparison and A-B-X listening tests. Click the down-arrow to switch the tab between A-B and A-B-X mode. www.sonnox.
5.2 5.2 Input and Output Panels 5 THE PRO-CODEC PLUG-IN Input and Output Panels The left hand panel of the plug-in features a large input signal meter and a button to launch the included Manager application for offline encoding and metadata editing. See section 7 for details. These meters show 2 dB per LED below -12 dBFs, and 0.5dB per LED above -12 dBFs.
5.2 Input and Output Panels 5 THE PRO-CODEC PLUG-IN removed by the encoding process. Enable the RECORD button to begin real-time encoding to disk for all ARMed codecs. Click the FILENAME button to specify where encoded files are written to when recording, and how they are named. 5.2.1 Surround Channel Mapping When the Pro-Codec Plug-In is inserted on a 6-channel track, the surround channel order menu button appears at the bottom of the INPUT panel.
5.3 5.3 Online Auditioning and Configuring Codecs 5 THE PRO-CODEC PLUG-IN Online Auditioning and Configuring Codecs The Pro-Codec Plug-In enables Fraunhofer codecs to be auditioned, compared and the encoded audio written to disk, all while the host workstation is operating.
5.3 Online Auditioning and Configuring Codecs 5 THE PRO-CODEC PLUG-IN Some items may be marked with an asterisk to indicate that the setting will require some form of resampling. Details will be shown in the lines at the bottom of the selector panel. Some combinations of bit rate, quality setting and sample rate might cause an encoder to down-sample internally (especially at the highest quality settings).
5.3 Online Auditioning and Configuring Codecs 5 THE PRO-CODEC PLUG-IN The codec settings selector also provides additional options for HD-AAC, and for auditioning down-mixing modes for the 5.1 MPS codecs: HD-AAC AAC-LC MPS (5.1) down-mixing modes www.sonnox.
5.3 Online Auditioning and Configuring Codecs 5.3.1 5 THE PRO-CODEC PLUG-IN The NMR Indicator Also featured in the FFT display is the NMR (Noise to Mask Ratio) indicator line. This provides an indication of the frequency areas where the difference between the codec output and the original input might be audible. The NMR indicator can be disabled by clicking on the NMR button (above the display). All lossy codecs will produce a very slightly different output from their input.
5.3 Online Auditioning and Configuring Codecs 5 THE PRO-CODEC PLUG-IN of frequency areas that might require examination. The NMR indicator is not present when HD-AAC is selected. Also, the NMR display is less accurate when SUM is selected; it is most accurate with single audio streams. Note: The difference signal used in the NMR calculation is absolute. For some low level signals the NMR might be relatively high, but any difference will be inaudible due to the low signal level.
5.3 Online Auditioning and Configuring Codecs 5.3.3 5 THE PRO-CODEC PLUG-IN Overloading Pre-Codec (Codec Headroom) It is possible, but not desirable, that the plug-in will be fed by an overloading input (sample values greater than 0 dBFS). In this case, the input meters will show clipping. This is separate to the possibility that a lossy encoder given a non-overloading input could produce a bitstream that overloads a decoder output.
5.4 5.4 Bitstream Level (TRIM Tab) 5 THE PRO-CODEC PLUG-IN Bitstream Level (TRIM Tab) Any form of filtering can, under certain circumstances, increase the peak level of the signal. Therefore, if your input is hot, the encoding process can produce overloads that are not seen until the signal is decoded. This effect can be very easily demonstrated with the Pro-Codec Plug-In. The Bitstream Level TRIM tab can be used to monitor this potential for overload.
5.5 Data Compression Factor (COMP Tab) 5 THE PRO-CODEC PLUG-IN unrepeatable maximum values. The discrepancies in both cases should be minor, and not all source audio and not all codecs will be affected. So, it is not always possible to trim exactly while auditioning, because a subsequent pass might have a slightly different maximum value. There is a technical reason for this, stemming from the difficulty of synchronizing the start point of the buffer that is used to input data to the codecs.
5.6 A-B Auditioning and A-B-X Testing (A-B Tab) 5.6 5.6.1 5 THE PRO-CODEC PLUG-IN A-B Auditioning and A-B-X Testing (A-B Tab) A-B Auditioning For simple and quick auditioning use AB Mode. Control is via the A-B tab. Clicking in the A or B columns will assign a codec to the A or B audition channels. Clicking in the B column adjacent to a selected A codec will automatically set the B column to the input signal (I/P). To revert to a codec for the B column, click on a cell non-adjacent to the A codec.
5.6 A-B Auditioning and A-B-X Testing (A-B Tab) 5 THE PRO-CODEC PLUG-IN button and the previously selected button. This means you can repeatedly alternate between A & X with your eyes closed (or B & X, or A & B) because you don’t need to move the mouse pointer. Eyes-closed auditioning might improve your listening focus! As with A-B mode, there is access to the input signal (I/P) by clicking in the B column adjacent to a selected A codec. Press RESET to reset the internal counters and begin a new test.
5.7 5.7 Processing Sequence 5 THE PRO-CODEC PLUG-IN Processing Sequence The concept underlying the development of this plug-in was that it should be the very last item in the mastering chain. A 16 or 24 bit master has been finalised and possibly rendered to a WAV file. What is now required is to take that finalised master and produce an encoded, data-compressed version (or versions) for end-user playback.
5.8 5.8 Online Encoding 5 THE PRO-CODEC PLUG-IN Online Encoding To encode a file in real time, first you have to record enable the codec. This is done by selecting the ARM buttons to the left of the codec list. Multiple files can be selected for simultaneous recording. To record straight away, press the RECORD button when the host is playing back audio; this will write the output of your selected codecs to disk. You cannot change the record ARM settings while dropped into RECORD: www.sonnox.
5.8 Online Encoding 5 THE PRO-CODEC PLUG-IN You can also ARM the codec when playback is stopped, so that codecs will start writing the instant you start host playback. Likewise, stopping playback will terminate the writing procedure. Record duration and exact data compression ratios are displayed (see screenshot above). Press the FILENAME FORMAT button to view the filename format pop-over window. This allows the user to specify the destination folder for the recorded files and the output filename elements.
5.8 Online Encoding 5 THE PRO-CODEC PLUG-IN dragging it either to the left or the right to a suitable position. Should you want to add or remove any of these, simply toggle its check box. Note: Care should be taken to make filenames distinct, to avoid confusion for files written concurrently. For example, if five mp3 codecs were selected with different bit rates, it would be wise to enable the BIT RATE option for the resultant filenames.
5.9 HD-AAC 5.9 5 THE PRO-CODEC PLUG-IN HD-AAC (Lossless Codec) A lossless codec is one that produces an output data stream that is an exact duplicate of the input audio data stream. In the simple case of a 24-bit wav file as input, the output of the HD- AAC lossless codec will be a wav file with identical audio data. When HD-AAC is used in a DAW via the Pro-Codec Plug-In, the situation is slightly more complicated because usually the input is not a simple 16 or 24 bit data stream.
5.9 HD-AAC 5 THE PRO-CODEC PLUG-IN button enabled, the audition point is after the HD-AAC encoder-decoder. You will notice that the DIFF signal in the FFT display will drop below -144 dB. (HD-AAC is lossless to 24 bits, so the DIFF signal has an amplitude smaller than 24 bits down. If the input signal to the codec is quantised to 24 bits, either by dither and truncation, or because it is unprocessed data from a 24 bit input file, the DIFF signal will drop below -180 dB).
5.9 HD-AAC 5.9.2 5 THE PRO-CODEC PLUG-IN Bit Depth The HD-AAC codec has a 16-bit mode that is available in the codec settings selector. The bit depth and dither settings are reflected in the bit meter operation when moniitoring HD-AAC codec, and they are reflected in the plug-in output signal. The settings are saved into presets and project settings. www.sonnox.
5.9 HD-AAC 5.9.3 5 THE PRO-CODEC PLUG-IN Dither and Truncation When encoding online, or preparing a session for render through the DAW, it is essential to provide the input to the HD-AAC codec with a correctly dithered and truncated audio data stream. As stated above, the plug-in should be the last element of the processing chain, and a dither/truncation plug-in should immediately precede it. This is particularly important if HD-AAC is to be used.
5.9 HD-AAC 5 THE PRO-CODEC PLUG-IN First, in order to see the effect on the noise floor we input 1kHz and 2kHz tones at -60dB. As this is a low-level signal at -60 dB, there is no activity on the top ten segments of the bit meter. Note the magnified scale down to -180 dB. (ALT + drag down on the dB scale.) HD-AAC 24 bit with correct dither and truncation prior to the Plug-In. HD-AAC 16 bit with correct dither and truncation prior to the Plug-In.
5.9 HD-AAC 5 THE PRO-CODEC PLUG-IN What if the input signal is not correctly prepared? HD-AAC 24 bit with INCORRECT or NO dither and truncation prior to the Plug-In. HD-AAC 24 bit internal dither is DISABLED. HD-AAC 16 bit with INCORRECT or NO dither and truncation prior to the Plug-In. HD-AAC 16 bit internal dither is DISABLED. In these cases, it is clear that the HD-AAC truncation to 16/24 bits is causing truncation distortion.
5.9 HD-AAC 5.9.4 5 THE PRO-CODEC PLUG-IN Internal Dither and Truncation The previous examples include the insertion of a dither/truncation plug-in in the audio path to provide correct treatment of the signal prior to the codec. For convenience, if a dither plug-in is not available, the 16/24 bit dither option can be enabled in the codec settings selector. Note: If the plug-in is subsequently bypassed to render to WAV, the resulting output will not be dithered and truncated correctly.
5.9 HD-AAC 5 THE PRO-CODEC PLUG-IN The bit meter indicates that there is no activity in bits greater than 24. The input to the codec is correctly dithered and truncated. The border for the bottom segment is green to indicate that the dither/truncation is provided internally. The bit meter will also indicate when you are dithering unnecessarily. Here a correctly dithered and truncated signal enters the plug-in, but the internal dither is also applied.
5.9 HD-AAC 5 THE PRO-CODEC PLUG-IN HD-AAC 16 bit with CORRECT dither and truncation prior to the Plug-In. Internal Trim is ENABLED. HD-AAC 16 bit internal dither is DISABLED. The image above shows a correctly dithered signal input to the plug-in, but the internal trim is non-zero. The bottom segment of the bit meter is flashing red to indicate an error condition.
5.9 HD-AAC 5 THE PRO-CODEC PLUG-IN HD-AAC 16 bit with CORRECT dither and truncation prior to the Plug-In. Internal Trim is ENABLED. HD-AAC 16 bit internal dither is ENABLED. Note: Again, it is preferable to avoid using the internal trim by lowering the level into the plug-in. www.sonnox.
5.9 HD-AAC 5.9.5 5 THE PRO-CODEC PLUG-IN Overloading HD-AAC The screenshot below illustrates the behaviour of HD-AAC under overloading conditions. A typical audio signal is shown with the display zoomed. The input level is such that the input meters show clipping. Since HD-AAC does not have internal headroom, the signal will clip. HD-AAC 16 bit with 16 bit input signal overload at the Plug-In input. HD-AAC 16 bit internal dither is DISABLED.
5.9 HD-AAC 5 THE PRO-CODEC PLUG-IN that is buried in the lossless codec. To do this, select AAC-LC CBR with the appropriate bit rate. Level Change If a level change is required in the plug-in, and implemented using the TRIM tab, again it is wise to verify the audition signal. Dither and Truncation It is necessary to correctly dither and truncate the input to the HD-AAC codec (lossless). The audition DIFF signal quickly indicates if correct dither and truncation is being applied.
5.10 5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN Description of Controls Touch Pad Controls Several controls in this plug-in use a ‘touch pad’ associated with a knob or slider. These controls (e.g.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN Sonnox Menu Button This provides access to a number of useful items: Clip Hold (input meter clip LEDs) These can be set to hold until clicked, or for only 2 or 5 seconds. Enable Sonnox Toolbar Shows or hides the Sonnox Preset Manager toolbar. Show Preset Name Path Shows or hides the Preset name path in the Preset Manager toolbar. Clip trigger Changes how an overload, or clip is measured on the input meters.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN Input Section Input Section SIGNAL The input meter indicates 2 dB per LED below -12dBFs, and 0.5dB per LED above -12dBFs. It includes peak-hold indication. The meter will be mono, stereo or multi-channel depending on context. CH. MAP (5.1 instances only) Use these options to match the input/output channel mapping of the plug-in to the channel mapping used in your host DAW. If you use SMPTE/ITU channel order, simply select this option.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN Codec List Section CODEC LIST Displays a list of codecs chosen for auditioning. The codec type, bit-rate and codec mode are displayed at all times. Any codec pre-loaded in the list can be auditioned without glitches. To remove a codec, click the small red ‘x’ at the right hand side of each row. ARM (x5) Prepares an activated codec in the codec list for writing to disk. MON (x5) These select the active codec for routing to the output section.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN Filename Format pop-up panel Path Shows the destination path for output files. Click the folder browse button to select a new output path. Filename Displays the complete string that will be written to an output folder. You can re-order any of the elements for a completely custom filename. The filename elements are: Custom String Displays the identifying name string of the filename, eg. a song name. Codec Add the codec type. Optional.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN Codec Settings selector Codec Click to select a codec from the list. Some codecs will not be available, depending on the host sample rate and the number of channels. For example, HE-AACv2 is stereo only. Bitrate Choose the bit rate of the selected codec. Some bit-rates may not be available, depending on the sample rate of the host DAW and the number of channels. If the bit rate is accompanied by an asterisk, the codec is resampling the audio stream.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN Dither Only visible if the selected codec is HD-AAC. Only enable 16 or 24 bit dither if the input to the plug-in has not already been dithered and truncated to either 16 or 24 bits. Downmixing mode Only visible if the selected codec is AAC-LC MPS or HE-AAC MPS. This allows you to audition the various Fraunhofer downmixing algorithms. By default, no downmixing takes place.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN CODEC When selected, will route the encoded-decoded signal to the output. DIFF When selected will route the difference signal to the output. The difference signal is the encoded-decoded signal subtracted from the unprocessed input signal. MASTER IN With the IN button selected, all processing is active. If not selected, the outputs are disabled. However, much of the processing remains active, for example, the FFT display and the overload detection.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN COMP (compression) Tab Comp Tab COMPRESSION RATIOS (x5) Shows an indication of the amount of data compression in the output data stream or file. The compression is expressed as a ratio, from 1:1 down to around 128:1. A yellow asterisk denotes an estimated value. A-B Auditioning Tab[1] Comp Tab A (x5) Selects the codec to be routed through A. B (x5) Selects the codec or input to be routed through B.
5.10 Description of Controls 5 THE PRO-CODEC PLUG-IN A-B-X Test Tab[1] Comp Tab A (x5) Selects the codec to be routed through A. B (x5) Selects the codec or input to be routed through B. A/B/X Glitchlessly switches output routing between active codecs selected in A or B, or the anonymous codec in X. RESET Sets the ABX machine back to a start condition. Resets counters to zero and sets X to either A or B. CHOOSE Increments cycle counter. Examines whether choice of A or B correctly matches X.
6 6 PRESET MANAGER TOOLBAR Preset Manager Toolbar The Sonnox Fraunhofer Pro-Codec Plug-In comes equipped with its own onboard Preset Manager, which is displayed at the top of the plug-in window. The reasoning behind this is to allow increased portability of your presets across all the host applications, while also providing a consistent and versatile interface.
6.1 Presets and Project/Session Data Handling 6.1 6 PRESET MANAGER TOOLBAR Presets and Project/Session Data Handling The Sonnox Fraunhofer Pro-Codec plug-in contains internal data not normally found in a plug-in, such as filenames and folder paths. This has prompted the adoption of a slightly different preset model in order to allow the creation and utilization of independent libraries of data presets. 6.1.
6.2 Plug-In Signal and Control Flow Diagram 6 PRESET MANAGER TOOLBAR Note: Sonnox Toolbar preset loads must match the session sample rate and the session channel configuration to avoid incompatible codec settings (the codecs are sensitive to session sample rate and channel configuration). Presets that are incompatible with the current instance will appear greyed out in the preset load menu.
7 7 THE PRO-CODEC MANAGER APPLICATION The Pro-Codec Manager Application The Pro-Codec Toolbox Manager is a standalone application 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. The user interface of the Manager is separated into five main sections: 2. File List 5. Metadata Editor . 1. Folder Browser 3.
7.1 Folder Browser 7.1 7 THE PRO-CODEC MANAGER APPLICATION Folder Browser The leftmost section of the Pro-Codec Manager presents controls for browsing folders on your system. From here, individual folders can be selected so that their contents can be loaded into the File List. This section describes the different components that make up the Folder Browser section, including details about some common operations you may need to perform.
7.1 Folder Browser 7.1.2 7 THE PRO-CODEC MANAGER APPLICATION 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 folders using the operating-system pop-up browser (accessible via the Browse button at the top of the section).
7.2 File List 7.1.3 7 THE PRO-CODEC MANAGER APPLICATION 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. 7.
7.2 File List 7.2.1 7 THE PRO-CODEC MANAGER APPLICATION Selecting Multiple Files for 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.
7.3 Encode-Decode Section 7.3 7.3.1 7 THE PRO-CODEC MANAGER APPLICATION Encode-Decode Section Encoding The Clip Safe button enables a level-correction feature. This works by decoding the newly compressed file, calculating the maximum sample value in the PCM stream and, if necessary, applying the precise amount of gain trim required when the source file is encoded a second time.
7.3 Encode-Decode Section 7.3.2 7 THE PRO-CODEC MANAGER APPLICATION Codec Settings Presets Codec settings can be saved as presets for later use. To display the codec settings preset manager, click the Codec Presets tab in the lower right-hand area of the Manager. Hover the mouse cursor over a preset name to preview the saved codec settings. Click on a preset name to load these settings into the Codec List.
7.3 Encode-Decode Section 7 THE PRO-CODEC MANAGER APPLICATION decoded to WAV/AIFF with the peaks intact and reduced to below 0 dBFS, potentially restoring some fidelity to the programme material. If the source audio file is very quiet, NORMALISE can be enabled in addition to CLIP SAFE in order to ensure that the decoded level of the file is as close to 0 dBFS as possible. Use the Output Path field to select where you would like the decoded files to be saved to.
7.4 Auditioning Files in the Manager 7.3.5 7 THE PRO-CODEC MANAGER APPLICATION Dither When Clip Safe or Clip Safe + Normalise are used, the Manager may need to dither after applying the required gain trim. When encoding, dither is only applied if an HD-AAC encode produces overs and requires some gain trim before the re-encode process. When decoding, dither is applied when any encoded file (HD-AAC or otherwise) requires gain trim before being written to 16 or 24 bit WAV/AIFF. 7.
7.5 The Metadata Editor 7.5 7 THE PRO-CODEC MANAGER APPLICATION The Metadata Editor 7.5.1 Overview The MP3 and M4A audio file formats can optionally contain information about a file. This information is commonly known as METADATA. Typical metadata tags could include the Title, Artist, Track Number, and Cover Art. The Title tag of a file is distinct from its file name.
7.5 The Metadata Editor 7 THE PRO-CODEC MANAGER APPLICATION Write to File Write the contents of the Metadata Editor to the selected file. This alters the selected file, and cannot be undone. 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.
7.5 The Metadata Editor 7.5.3 7 THE PRO-CODEC MANAGER APPLICATION 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.
7.5 The Metadata Editor 7.5.4 7 THE PRO-CODEC MANAGER APPLICATION 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.
7.5 The Metadata Editor 7.5.6 7 THE PRO-CODEC MANAGER APPLICATION Writing Tags to Multiple Files Metadata tags are written to all selected files. Unsupported tags will simply be skipped. For example, if M4A and MP3 files are selected, the Gapless tag will be skipped for all MP3 files, but still written to the selected M4A files. 7.5.7 Importing Tags from Another File Any audio files that contain metadata are listed in the File List with a small arrow button in the right-most column.
7.5 The Metadata Editor 7 THE PRO-CODEC MANAGER APPLICATION The list of presets is ordered alphabetically, and is immediately re-ordered when a new preset is saved. Empty presets cannot be saved, so the + button is not displayed when the Metadata Editor is empty. To delete or remove a preset, hover your mouse cursor over the preset name, and press the red X button that appears at the right-hand side of the row. A pop-up window will ask for confirmation before deleting the preset. 7.5.
7.6 7.
8 8 ONLINE VS. OFFLINE ENCODING Online vs. Offline Encoding We can now discuss the advantages and disadvantages of online encoding with the Plug-In (see section 5) and offline encoding with the Manager application (see section 7). Offline Encoding is now done with the included desktop application – the Pro-Codec Manager. Advantages of Offline Encoding: • Bit stream overloads are consistent, • The original file length features of the files can be employed (meaning consistent start and end points).
8.1 8.1 When to Use Online Encode 8 ONLINE VS. OFFLINE ENCODING When to Use Online Encode In general, offline encoding with the Pro-Codec Manager application should be used when a bounced WAV/AIFF file exists. If there is no WAV/AIFF file (perhaps instead there is a work-in-progress mix) online mode will be quicker and easier, hence more appropriate.
9 9 SPECIFICATIONS Specifications 9.1 9.1.1 Plug-In Delays and CPU Usage The sample delay (latency) of the plug-in depends upon the particular codecs selected. The monitor outputs are delay compensated, so if more than one codec is selected in the Codec List, then the reported delay is the maximum of the individual codec delays. This field is updated in the GUI immediately a new codec or other setting is selected.
9.1 Plug-In 9 SPECIFICATIONS CPU Use All codecs are mathematically intense (some more than others), and some have significant latency as a result. The user can take advantage of advances in CPU power in modern computers if appropriate, but can also use the plug-in extensively with older and possibly lower-powered computers by selecting fewer codecs simultaneously. In particular, the HD-AAC lossless codec creates a heavy CPU load.
9.1 Plug-In 9 SPECIFICATIONS Graphical Display Frequency 20 Hz – 20 kHz (44.1 and 48 kHz) Graphical Display Gain +10 dB – -120 dB (to -180 dB with zoom) Bitstream Level Trim -12 dB – 0 dB Trim Meter 0 dB – +10 dB Trim Display -144 dB to +10 dB www.sonnox.
9.2 Manager 9.2 9 SPECIFICATIONS Manager 9.2.1 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.
9.3 Codec Specifications 9.3 Codec Specifications 9.3.1 Bit Rate vs Sample Rate 9 SPECIFICATIONS Available bit rates are dependent upon the selected sample rate. Encoder MP3 Channel Configurations Mono, Stereo Sample Rates (kHz) 8, 11.025, 12, 16, 22.05, 24, 32, 44.1, 48 Bit Rates (kbps) Mono: 8-320 CBR and VBR Stereo: 16-320 CBR and VBR Encoder AAC-LC, HE-AAC Channel Configurations Mono, Stereo, 5.1 Sample Rates (kHz) AAC-LC: 11.025-96 HE-AAC: 22.05-96 HE-AAC v2: 22.
9.3 Codec Specifications 9 SPECIFICATIONS Encoder HD-AAC Channel Configurations Mono, Stereo, 5.1 Sample Rates (kHz) 44.1, 48, 88.2, 96, 176.4, 192 Bit Rates (kbps) Variable (lossless) Limitations Supported oversampling modes: 1 for input sample rate 44.1 or 48kHz 2 for input sample rate 88.2 or 96kHz 4 for input sample rate 176.4 or 192kHz 9.3.2 Codec and Session Sample Rate The Plug-In and many of the codecs are sensitive to the session sample rate and channel configuration.
9.3 Codec Specifications 9 SPECIFICATIONS doesn’t support the sample rate at any bit rate, the codec will default to AAC-LC at the closest bit rate. To illustrate this behaviour, consider a stereo session at 48 kHz with three codecs selected.
9.3 Codec Specifications 9 SPECIFICATIONS A Sonnox Fraunhofer Pro-Codec is instantiated and shows the default codec as AAC-LC 192 kpbs. Note the usual default of 256 kbps is not valid for a mono WAV file (see section 9.3.4 for the full table of codec supported sample rates). If the 22.05 kHz file is selected, and play stopped and re-started, the codec will automatically select 28 kbps (which is the closest to 192 kbps that the codec supports at 22.05 kHz). If the 44.
9.3 Codec Specifications 9 SPECIFICATIONS Summary These complications arise mostly when low sample rates (32 kHz) are combined with low bit rate codecs; or when high sample rates are combined with high bit rates. Generally Pro Tools, Logic, Cubase, and Nuendo are among the hosts that are immune to this behaviour, but Sequoia, Samplitude and WaveLab are examples of hosts that can exhibit these issues.
9.3 Codec Specifications 9 SPECIFICATIONS MP3 stereo, session 44.1 kHz or 88.2 kHz Bit Rate Supported Preferred Quality Setting Actual (kbps) Sample Rates Sample Rate Sample Rate (kHz) (kHz) Used (kHz) 96 32/44.1 32 Fast 44.1 96 32/44.1 32 Highest 32 128 32/44.1/48 44.1 Fast 44.1 128 32/44.1/48 44.1 Highest 44.1 320 32/44.1/48 44.1/48 Fast 44.1 320 32/44.1/48 44.1/48 Highest 44.
9.3 Codec Specifications 9.3.4 9 SPECIFICATIONS Preferred Sample Rates The supported session sample rates of the plug-in are from 32 kHz minimum to 192 kHz maximum (where the host DAW allows). The supported codec sample rates are from 8 kHz minimnum to a maximum of 48 kHz (MP3), 96 kHz (AAC family) or 192 kHz (HD-AAC only, see above). Under certain settings at higher session sample rates, downsampling occurs between the session and the audition path, or between the session and the encoder.
9.3 Codec Specifications 9 SPECIFICATIONS AAC-LC Bit Rate Range (kbps) Supported Sample Rates Preferred Sample Rate Channel Count 32 – 55 32 32 1 56 – 127 32/44.1/48 44.1 1 128 – 191 32/48/96 48 1 192 – 264 44.1/48/96 96 1 264 – 288 48/88.2/96 96 1 40 – 95 32 32 2 96 – 111 32/44.1/48 32 2 112 – 255 32/44.1/48 44.1 2 256 – 384 32/48/96 48 2 384 – 529 44.1/48/96 96 2 529 – 576 48/88.2/96 96 2 160 – 239 32 32 5, 5.1 240 – 279 32/44.1/48 32 5, 5.
9.3 Codec Specifications 9 SPECIFICATIONS HE-AAC v2 Bit Rate Range (kbps) Supported Sample Rates Preferred Sample Rate Channel Count 12 – 17 32 32 2 18 – 39 32/44.1/48 44.1 2 40 – 56 32/44.1/48 48 2 AAC-LC MPS (MPEG Surround) Bit Rate Range (kbps) Supported Sample Rates Preferred Sample Rate Channel Count 192 44.1/48 44.1 5.1 256 44.1/48 44.1 5.1 320 44.1/48 44.1 5.
10 10 COMMERCIAL USE OF MP3 CONTENT Commercial use of MP3 Content It is important to distinguish between the use of codecs and the use of content produced by the codecs. 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.
12 11 SYSTEM REQUIREMENTS Supported Platforms • Avid Pro Tools (AAX Native 32/64-bit) • VST hosts (32/64-bit) • AU hosts (32/64-bit) • Mac Intel OSX 10.6 or higher • Windows 7 and 8 (32/64-bit) 12 System Requirements For latest System requirements, please visit www.sonnox.com. All versions • Free iLok account • Appropriate product licence • iLok2 Pro Tools • Approved Digidesign/Avid CPU and hardware configuration • Pro Tools 10.3.
13 13 COPYRIGHT AND ACKNOWLEDGEMENTS Copyright and Acknowledgements Trademarks and content copyright © 2007-present Sonnox® Ltd. All rights reserved. Sonnox® and the five dots logo are registered trademarks of Sonnox Ltd. This product is manufactured and supplied by Sonnox Ltd. This product is protected by one or more European and/or US patents. DIGIDESIGN, AVID and PRO TOOLS are trademarks or registered trademarks of Avid Technology Inc. VST is a trademark of Steinberg AG.
