Hi Sakari, On Tuesday 10 January 2012 10:52:26 Sakari Ailus wrote: > Laurent Pinchart wrote: > > On Tuesday 10 January 2012 10:42:58 Sakari Ailus wrote: > >> Laurent Pinchart wrote: > >>> On Tuesday 10 January 2012 00:26:46 Sakari Ailus wrote: > >>>> Laurent Pinchart wrote: > >>>>> On Monday 09 January 2012 23:32:06 Sakari Ailus wrote: > >>>>>> Laurent Pinchart wrote: > >>>>>>> On Monday 09 January 2012 18:38:25 Sakari Ailus wrote: > >>>> ... > >>>> > >>>>>>>> A fourth section may be required as well: at this level the frame > >>>>>>>> rate (or frame time) range makes more sense than the low-level > >>>>>>>> blanking values. The blanking values can be calculated from the > >>>>>>>> frame time and a flag which tells whether either horizontal or > >>>>>>>> vertical blanking should be preferred. > >>>>>>> > >>>>>>> How does one typically select between horizontal and vertical > >>>>>>> blanking ? Do mixed modes make sense ? > >>>>>> > >>>>>> There are minimums and maximums for both. You can increase the frame > >>>>>> time by increasing value for either or both of them --- to achieve > >>>>>> very long frame times you may have to use both, but that's not very > >>>>>> common in practice. I think we should have a flag to tell which one > >>>>>> should be increased first --- the effect would be to have the > >>>>>> minimum possible value on the other. > >>>>> > >>>>> But how do you decide in practice which one to increase when you're > >>>>> an application (or middleware) developer ? > >>>> > >>>> I think it's the responsibility of this library to do that, unless the > >>>> user wants really, really precise control in which case they have to > >>>> deal with the blanking values directly. In general it should be the > >>>> library. > >>> > >>> And how does the library decide ? :-) > >> > >> frame_time = pixel_rate / ((width + hblank) * (height + vblank)) > >> > >> The user gives you frame time and the configuration contains the > >> information which one to prefer. Let's say the user prefers hblank (from > > > >> the above): > > That was my question, how does the user decide whether hblank or vblank > > is preferred ? > > I think that should be defined in the configuration itself. It's very > unlikely there's any need to change this dynamically. Sure, but that's not my point. How does the user decide in the first place when writing the configuration ? -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
