B-intra enabled for medium-preset

[The Stilt]

B-intra is currently enabled for medium, slower, veryslow and placebo preset. Based on the documentation (preset options), it should be only enabled on the three of the slowest presets. B-intra being disabled even on the slow-preset supports the assumption that this is not intentional.

[Dendraspis]

Current state:

preset	0	1	2	3	4	5	6	7	8	9
b-intra [CODE]	0	0	0	0	0	1	0	1	1	1
b-intra [DOCS]	0	0	0	0	0	0	0	1	1	1

‌

Enables the evaluation of intra modes in B slices. Default disabled.

Sources:
https://x265.readthedocs.io/en/default/cli.html#cmdoption-b-intra
https://x265.readthedocs.io/en/default/presets.html

[Trent Piepho]

I found this same thing and came here to report it.

I think the what was intended is that bIntraInBFrame be turned on for medium (5) and above and the docs were not updated. I.e., yhe mistake is not preset 5 being on, but preset 6 being off.

It was as documented until commit 94c9ba1f0d4341a1854129cc48c08deac9f31f73, where the default value was changed to true along with changes to some other settings' defaults. It seems like the purpose of the commit was move b-intra from veryslow to default.

Then in commit e3ad6c927754a235f5b7ae2c303f5218edf95ea7 the presets were adjusted to produce the same values as before. So b-intra was explicitly turned off in the presets below medium. And here’s the mistake: It was turned off for slow too because it was off there before. So only the medium preset was changed. But it doesn’t make sense to change only medium.

These commits above are kind of sloppy. Git username isn’t correct. They add whitespace errors. So it follows that they also were a bit sloppy when it comes to updating the docs or considering that turning b-intra on at 5, off at 6, then on again at 7 doesn’t make sense.