RetroTINK-4K Custom Input Mode Detection
Instructions
Custom input mode definitions (up to 24)
can be stored in the 'input_database.txt' file. If a RGB or YPbPr
signal does not match to an existing known definition, the RT4K will attempt to
find a match in this database.
The parameters for each custom input mode is a single line of csv values with the format:
1. Minimum
acceptable frame rate (floating point)
2. Maximum
acceptable frame rate (floating point)
3. Minimum
acceptable number of lines per frame (integer, note interlaced signals are
treated on a frame, not field basis, so 525 for 480i or 625 for 576i)
4. Maximum
acceptable number of lines per frame (integer)
5. Horizontal
Sync Polarity (integer, 0 = don't care, 1 = negative, 2 = positive)
6. Vertical
Sync Polarity (integer, 0 = don't care, 1 = negative, 2 = positive)
7. Horizontal
Sync + Back Porch Pixels (integer)
8. Horizontal
Active Pixels (integer)
9. Horizontal
Total (Front Porch + Sync + Back Porch + Active) Pixels (integer)
10. Vertical
Sync + Back Porch Lines (integer)
11. Vertical
Active Lines (integer)
12. Vertical
Total (Front Porch + Sync + Back Porch + Active) Lines (integer)
13. Actual
Horizontal Sampling Pixels (integer)
14. PAR
Factor (float)
15. Desired
Slot Number in Profile (integer 1-24)
16. String
Name for Mode
Parameters 1-6 are checked against an
unknown input format. If a match is found, Parameters 7-14 are then used for sampling
and cropping the signal.
Note: The actual sample rate (item 13) can
be different from the "canonical" sample rate (item 9) for the input
mode.
As an example, see the input mode
definition for a standard 480i signal:
"55.0, 65.0, 523, 527, 0, 0, 1, 122,
720, 858, 18, 240, 263, 1716, 0.90909, 10, 480iCustom"
BT.656 480i signals are conventionally
sampled with 858 pixels/per line with a PAR of 10/11 (0.9090). However, the modeline specifies that the RT4K should actually sample at
1716 pixels per line (which will result in improved image quality due to
oversampling). The RT4K will use the "canonical" sample rate, the PAR
factor and the actual sample rate such that the final image is scaled
correctly.