File Information Modules 

 

Stream Manipulation Options 

The choices for stream manipulation depend on the source file type selected, as QT/MOV files and MXF files are inherently different in terms of internal structure. For MXF files, you will see the following, but the dialog does reconfigure slightly based upon the Stream Structure setting. Starting at the top of the dialog, we currently (September 2021) support three types of MXF files, selectable from the drop down menu.

These choices are:

• OP1A
• OP1A with RDD9 characteristics
• OP1A with D10 characteristics (Note that the D10 option is only compatible with 8 channel files) 

Selecting base OP1A will create files with the following –

• Any stream structure available to select
• Any number of channels of audio (between 0 and 64)
• Insertion of Language tags is supported
• BWF type audio container
• SDTI
• Simple track numbering available as choice – ie 1, 2, 3 etc.

 

Selecting RDD9 will create files with the following characteristics

• Mono stream structure only
• 2, 4, 8 audio channels, or 16 audio channels if ARD_ZDF is also selected
• Language tags are not supported
• AES type audio container
• SDTI
• Simple track numbering – 1, 2, 3 etc always used

 

Selecting D10 will create files with the following characteristics

• Single stream structure, so all audio channels interleaved in to this single stream
• Not more than 8 audio channels are supported
• Language tags are not supported
• D10 type audio container
• SDTI
• Simple track numbering – 1, 2, 3 etc always used

 

The dialog reconfigures based upon this initial selection so the remaining options described here may not always be available. Please see the table in appendix 2 to see which combinations of video frame rates and codec types are supported for file manipulation operations. Note though that for all simple workflows where the input and output type are selected as ‘Media’ and the number of channels remains constant, then all common frame rates and codecs are supported. So the grid of options in the appendix only applies when the source and destination types are selected as ‘MXF’, and a new file is being authored.

Next you can select the required stream structure for the output file that is being created.

The available Stream Structures are:

• Mono Stream Structure – creates an output file where each audio channel occupies a single stream
• Stereo Stream Structure – creates an output file where each pair of audio channels occupies a single stream
• Single Stream Structure – creates an output file where all of the audio channels are interleaved in a single stream. 
• Source Stream Structure – creates an output file where the stream structure is identical to that of the source file.
• Advanced Stream Structure – creates an output file where you can flexibly define the number of channels to include in each stream.

 

Advanced Stream Structure

The purpose of this option is to let you assign one stream per audio track. Once you select this from the drop down menu, a dialog appears to let you assign the number of audio channels to each stream.

You select the number of audio channels for the first stream and click ‘Add Stream++’. Then select the number of channels for the second stream, and so on, until all the audio channels in your workflow have been assigned. As you create a stream, the details appear on the left of the dialog.

Here is the same dialog, but now configured for a 16 channel file, containing stereo, 5.1, stereo, and 5.1 and this is a typical configuration that you might need for the newer AS11 formats.

You can choose what happens to the timecode in the destination file. You have the choice of entering a new start timecode for the content, or of using the same timecode as the source file.

For OP1A and RDD9 file characteristics, you can also select ARD_ZDF characteristics. If you chose OP1A, enabling this option makes the following change –

The Audio container changes from BWF to being AES.

You can also select Simple Track Numbering if required. Note this control is ignored for RRD and D10 formats as simple track numbering is mandatory for those formats. Simple track numbers is essentially using the lowest numbers for streams, starting usually with 0. If you selected Source Stream Structure, the metadata in the output file is fixed. However if you change to any of the other stream structures, and if you have the File Metadata option, you have the ability to insert language and channel position tags. The functionality will depend on the chosen stream structure and your choice of language tag format.

The available Language Tag formats are:

• DMS-1
• AS-11

If you click to enable ‘Language Tags’, and extra section appears where you can enter the required language information. You can enter one language per stream, so you need to select mono or stereo streams for most applications of this metadata.

DMS-1 metadata format lets you add language information only AS-11 metadata format lets you add language information and channel layout information. In both metadata formats, the language is entered as free text.

The AS11 channel position metadata is selected from a drop down menu and one value is available per stream. So for mono streams you can individually chose a channel to be Left, or Right, etc. With stereo streams you must choose a pair of values for the two channels, such as Centre + LFE.

In the following screenshot I have selected to add AS-11 metadata, in an advanced stream format. Therefore I can add language information for each stream, and specify the channel layout for the channels in each stream.

Under the Language metadata information, you can optionally control Timecode information. The feature is part of the File Manipulation module.

Here I have chosen to stamp 10:00:00:00 timecode in to the destination file if there is no timecode in the source file, but to carry the source timecode through to the destination file, if available.

 

If timecode control is enabled here, then it is then possible to specify the required timecode over the API. Click ‘Next >’ to exit this stage of workflow setup.

 

QT/MOV Stream Manipulation and Metadata Options

If you are working with QT/MOV files, you have a slightly different dialog to choose stream and metadata choices.

The available Stream Structures are:

• Mono Stream Structure – creates an output file where each audio channel occupies a single stream
• Stereo Stream Structure – creates an output file where each pair of audio channels occupies a single stream
• Single Stream Structure – creates an output file where all of the audio channels are interleaved in a single stream
• Source Stream Structure – creates an output file where the stream structure is identical to that of the source file.

If you select the ‘Source Stream Structure’, it is not possible to add channel layout metadata. However if you select ‘Mono Stream Structure’ or ‘Stereo Stream Structure’ you have the option to add layout metadata. The choices depend on the selected stream structure.

For Mono streams, you can specify any of ‘Left’, ‘Right’, ‘Centre’, ‘LFE’, ‘Left Surround’, ‘Right Surround’, ‘Left Total’ and ‘Right Total’, or Discrete Channel Zero through to Sixty Four (the number of possible Discrete Channel tags varies with the number of channels in the file). You can also add Language ID tags, and these can be in ISO format, or Standard format. In ISO format, you have to enter a valid three letter code for each stream. In Standard format, you select a predefined language ID for each stream from a drop down menu.

Under the Channel Tag section, you can optionally control Timecode information.

Here I have chosen to stamp 10:00:00:00 timecode in to the file. Alternatively I could have specified to carry the source timecode over to the destination file.

If timecode control is enabled here, then it is then possible to specify the required timecode over the API.

You can also select to create an Audio Only version of the MOV file. This keeps as much data from the original MOV as possible, but the video essence track is removed. This has the advantage of creating much smaller files, but still retaining the channel layout and language ID metadata labelling, which is not possible with WAV files.

Click ‘Next >’ to exit this stage of workflow setup.

Click ‘Save Settings’ and your new workflow is complete and ready for testing!