Pre-roll/Post-roll
Pre-roll is the amount of time elapsed before an event occurs. Post-roll is the amount of time after the event. Pre and post-roll have various uses in Sound Forge software. Pre-roll can be added to a crossfade preview to listen to the sound before the crossfade begins to give context to it. Pre-roll can also be used in the Playlist to hear previous regions when playback is initiated from the middle of the Playlist.
Preset
A preset calls up a bulk setting of a function in Sound Forge software. If you like the way you adjusted the EQ but do not want to have to spend the time getting it back for later use, save it as a preset. All presets show up in the drop-down list on the top of most function dialogs in Sound Forge software.
Punch-In
Punching-in during recording means automatically starting and stopping recording at user-specified times.
Pulldown
In telecine conversion, fields are added to convert 24 fps film to 30 fps video.
In 2-3 pulldown, for example, the first frame is scanned into two fields, the second frame is scanned into three fields, and so on for the duration of the film. 2-3 pulldown is the standard for NTSC broadcasts of 24p material. Use 2-3 pulldown when printing to tape, but not when you intend to use the rendered video as source media. Removing 2-3 pulldown is inefficient because the pulldown fields that are created for frame 3 span two frames:
24 fps film (top) and resulting NTSC video with 2-3 pulldown fields (bottom)
Use 2-3-3-2 pulldown when you plan to use your rendered video as source media. When removing 2-3-3-2 pulldown, Sound Forge software simply discards frame three and merges the pulldown fields in the remaining frames:
24 fps film (top) and resulting NTSC video with 2-3-3-2 pulldown fields (bottom)
Pulse Code Modulation (PCM)
PCM is the most common representation of uncompressed audio signals. This method of coding yields the highest fidelity possible when using digital storage. PCM is the standard format for .wav and .aif files.
Q Subcode
Compact disc players use the Q channel to display the music playing time. The Q channel is broken down into three modes:
•Mode 1 Contains the running times from both the beginning of the disc (total disc time) and the beginning of the track (track relative time).
•Mode 2 Identifies the track number, who recorded the track, where it was recorded and in what year.
•Mode 3 Identifies UPC media catalog number for the disc.
A special mode of Q data is stored within the lead-in area. This Q data contains information on two- or four- channel format, copy protection, and pre-emphasis.
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