Perform various types of temporal field interlacing.
Frames are counted starting from 1, so the first input frame is considered odd.
The filter accepts the following options:
- mode
-
Specify the mode of the interlacing. This option can also be specified as a value alone. See below for a list of values for this option.
Available values are:
- merge, 0
-
Move odd frames into the upper field, even into the lower field, generating a double height frame at half frame rate.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 Output: 11111 33333 22222 44444 11111 33333 22222 44444 11111 33333 22222 44444 11111 33333 22222 44444
- drop_even, 1
-
Only output odd frames, even frames are dropped, generating a frame with unchanged height at half frame rate.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 Output: 11111 33333 11111 33333 11111 33333 11111 33333
- drop_odd, 2
-
Only output even frames, odd frames are dropped, generating a frame with unchanged height at half frame rate.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 Output: 22222 44444 22222 44444 22222 44444 22222 44444 - pad, 3
-
Expand each frame to full height, but pad alternate lines with black, generating a frame with double height at the same input frame rate.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 Output: 11111 ..... 33333 ..... ..... 22222 ..... 44444 11111 ..... 33333 ..... ..... 22222 ..... 44444 11111 ..... 33333 ..... ..... 22222 ..... 44444 11111 ..... 33333 ..... ..... 22222 ..... 44444
- interleave_top, 4
-
Interleave the upper field from odd frames with the lower field from even frames, generating a frame with unchanged height at half frame rate.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111<- 22222 33333<- 44444 11111 22222<- 33333 44444<- 11111<- 22222 33333<- 44444 11111 22222<- 33333 44444<- Output: 11111 33333 22222 44444 11111 33333 22222 44444
- interleave_bottom, 5
-
Interleave the lower field from odd frames with the upper field from even frames, generating a frame with unchanged height at half frame rate.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111 22222<- 33333 44444<- 11111<- 22222 33333<- 44444 11111 22222<- 33333 44444<- 11111<- 22222 33333<- 44444 Output: 22222 44444 11111 33333 22222 44444 11111 33333
- interlacex2, 6
-
Double frame rate with unchanged height. Frames are inserted each containing the second temporal field from the previous input frame and the first temporal field from the next input frame. This mode relies on the top_field_first flag. Useful for interlaced video displays with no field synchronisation.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 Output: 11111 22222 22222 33333 33333 44444 44444 11111 11111 22222 22222 33333 33333 44444 11111 22222 22222 33333 33333 44444 44444 11111 11111 22222 22222 33333 33333 44444
- mergex2, 7
-
Move odd frames into the upper field, even into the lower field, generating a double height frame at same frame rate.
------> time Input: Frame 1 Frame 2 Frame 3 Frame 4 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 11111 22222 33333 44444 Output: 11111 33333 33333 55555 22222 22222 44444 44444 11111 33333 33333 55555 22222 22222 44444 44444 11111 33333 33333 55555 22222 22222 44444 44444 11111 33333 33333 55555 22222 22222 44444 44444
Numeric values are deprecated but are accepted for backward compatibility reasons.
Default mode is
merge. - flags
-
Specify flags influencing the filter process.
Available value for flags is:
- low_pass_filter, vlpf
-
Enable linear vertical low-pass filtering in the filter. Vertical low-pass filtering is required when creating an interlaced destination from a progressive source which contains high-frequency vertical detail. Filtering will reduce interlace ’twitter’ and Moire patterning.
- complex_filter, cvlpf
-
Enable complex vertical low-pass filtering. This will slightly less reduce interlace ’twitter’ and Moire patterning but better retain detail and subjective sharpness impression.
- bypass_il
-
Bypass already interlaced frames, only adjust the frame rate.
Vertical low-pass filtering and bypassing already interlaced frames can only be enabled for modeinterleave_top and interleave_bottom.