13. Input Source File Ser vice
Image13-1
Videopixels
A Video Signal
B Image
C TotalPixels
DStartPixels
EActivePixels
Image13-2
Videoclamping
A Clamp signal
B Leadingedge s ync signal
C Trailingedge sync signal
D Clamppulse delay
E Clamp pulse width
3:2 pull-down
Methodused to map the 24 fps of film onto the 30 fps (60 fields) or 25 fps (50 fields), so that one film frame occupies
threevideo fields, the next two, etc. Itmeans the two fields of every other video frame come from different film frames
makingoperations such as rotoscoping impossible, and requiring care in editing. Some sophisticated equipment can
unravel the 3:2 sequence to allow frame-by-frame treatmentand subsequently re-compose 3:2. The 3:2 sequence
repeatsevery five video frames and four film frames, the latter identified as A-D. Only film frame A is fully on a video
frameand so exists at one time code only, making it the editable point of the video sequence.
2:2 pull-down
Thepro cessof transferring 24-frames/sec film format into video by repeating each frame as two video fields. ( AD )
Artefacts
Undesirable elements or defects in a video picture. These may occur naturally in the video process and must be
eliminated in order toachieve a high-quality picture. Most common in analog are cross color and cross luminance.
Mostcommon in digital are macroblocks, which resemble pixelation of the video image.
13.4 Editing a FileHow to enter the Edit File menu:
1. From the adjustment mode m enu, select item RANDOM ACCESS. (menu 13-9)
TheRandom Access adjustment menu appears on-screen and in the graphical display. (menu 13-10)
2. From the Random Access adjustment mode menu, select item FILE SERVICE.
TheF ile Service menu appears on-screen and in the graphical display. (menu 13-11)
3. From the File Service menu, select item EDIT.
TheE ditF ile menu appears on-screen and in the graphical display. The Edit File menu contains a list of all stored files with on
top ofthe list the active file (mostly to be edited). (menu 13-12)
4. Select the filewhich has to be edited.
5. Press ENTER (RCU) or the selection wheel to confirm.
TheEdit File menu for that specific file appears on-screen and in the graphical display showing all the file parameters which can
bechanged. The file parameters are spread out over two menus, linked via item OPTION.
Parameters whichar e notadjustable are displayed light grey in the menu. (menu 13-13)
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