HD STANDARDS
In terms of broadcast television, the following formats are the most relevant:-
Format |
No. of Horizontal Lines |
Frame/Field Rate |
Vertical Scan Pattern |
1080/60i |
1080 |
30 Frames/sec |
Interlace |
1080/59.94i |
1080 |
29.97 Frames/sec |
Interlace |
1080/50i |
1080 |
25 Frames/sec |
Interlace |
1080/30Psf |
1080 |
30 Frames/sec |
Progressive Segmented Frames |
1080/29.97Psf |
1080 |
29.97 Frames/sec |
Progressive Segmented Frames |
1080/25Psf |
1080 |
25 Frames/sec |
Progressive Segmented Frames |
1080/24Psf |
1080 |
24 Frames/sec |
Progressive Segmented Frames |
1080/23.98Psf |
1080 |
23.98 Frames/sec |
Progressive Segmented Frames |
720/60p |
720 |
60 Frames/sec |
“True” Progressive |
720/59.94p |
720 |
59.94 Frames/sec |
“True” Progressive |
720/50p |
720 |
50 Frames/sec |
“True” Progressive |
The above formats are based on 2 line standards (1080, 720) and 3 scan patterns which are:
- Interlace
This is the long established, conventional TV scan pattern where a frame is composed of 2 interlaced fields; one containing the odd-numbered horizontal picture lines, followed by one containing the even-numbered lines scanned slightly later in time. The second field has the effect of filling in the vertical gaps between lines in the first field.
- Progressive
In this case, horizontal picture lines are scanned sequentially from the top to the bottom of the frame, with no field components.
- Progressive Segmented Frames (Psf)
Psf is a hybrid of the 2 previous scan patterns. In the camera, a complete progressive frame is scanned sequentially into a buffer memory from a `snapshot` picture stored once every frame period.
Information courtesy of Hi-DefHire.com