Hi Hans, On 28-03-2017 11:07, Hans Verkuil wrote: > On 27/03/17 13:58, Jose Abreu wrote: >> Hi Hans, >> >> >> On 24-03-2017 12:28, Hans Verkuil wrote: >>> On 03/24/17 13:21, Jose Abreu wrote: >>>> Hi Hans, >>>> >>>> >>>> On 24-03-2017 12:12, Hans Verkuil wrote: >>>>> On 03/24/17 12:52, Jose Abreu wrote: >>>>>> Hi Hans, >>>>>> >>>>>> >>>>>>>> Can you please review this series, when possible? And if you >>>>>>>> could test it on cobalt it would be great :) >>>>>>> Hopefully next week. >>>>>> Thanks :) >>>>>> >>>>>>> Did you have some real-world numbers w.r.t. measured >>>>>>> pixelclock frequencies and 60 vs 59.94 Hz and 24 vs 23.976 Hz? >>>>>> I did make some measurements but I'm afraid I didn't yet test >>>>>> with many sources (I mostly tested with signal generators which >>>>>> should have a higher precision clock than real sources). I have a >>>>>> bunch of players here, I will test them as soon as I can. >>>>>> Regarding precision: for our controller is theoretically and >>>>>> effectively enough: The worst case is for 640x480, and even in >>>>>> that case the difference between 60Hz and 59.94Hz is > 1 unit of >>>>>> the measuring register. This still doesn't solve the problem of >>>>>> having a bad source with a bad clock, but I don't know if we can >>>>>> do much more about that. >>>>> I would really like to see a table with different sources sending >>>>> these different framerates and the value that your HW detects. >>>>> >>>>> If there is an obvious and clear difference, then this feature makes >>>>> sense. If it is all over the place, then I need to think about this >>>>> some more. >>>>> >>>>> To be honest, I expect that you will see 'an obvious and clear' >>>>> difference, but that is no more than a gut feeling at the moment and >>>>> I would like to see some proper test results. >>>> Ok, I will make a table. The test procedure will be like this: >>>> - Measure pixel clock value using certified HDMI analyzer >>>> - Measure pixel clock using our controller >>>> - Compare the values obtained from analyzer, controller and >>>> the values that the source is telling to send (the value >>>> displayed in source menu for example [though, some of them may >>>> not discriminate the exact frame rate, thats why analyzer should >>>> be used also]). >>>> >>>> Seems ok? I will need some time, something like a week because my >>>> setup was "borrowed". >>> That sounds good. Sorry for adding to your workload, but there is no >>> point to have a flag that in practice is meaningless. >>> >>> I'm actually very curious about the results! >> I managed to do the tests but unfortunately I can't publish the >> full results (at least until I get approval). >> >> I can say that the results look good. As you expected we have >> some sources with a bad clock but this is correctly detected by >> the controller (and also by the HDMI analyzer). >> >> Using the v4l2_calc_framerate function I managed to get this: >> >> | Source | Resolution | v4l2_calc_framerate() >> ------------------------------------------------------------------------------ >> | Analyzer 1 | 640x480@59.94 | 59.92 >> | Analyzer 1 | 640x480@60 | 60 >> | Analyzer 1 | 1920x1080@60 | 60 >> | Player 1 | 1920x1080@59.94 | 59.94 >> | Player 2 | 1920x1080@59.94 | 59.93 >> | Player 3 | 3840x2160@59.94 | 59.94 >> | Player 4 | 1920x1080@59.94 | 59.94 >> | Player 5 | 1920x1080@59.94 | 59.93 >> | Player 6 | 1280x720@50 | 50 >> | Player 7 | 1920x1080@59.94 | 59.93 >> | Player 8 | 1920x1080@60 | 60 >> | Analyzer 2 | 720x480@59.94 | 59.94 >> | Analyzer 2 | 720x480@60 | 60 >> | Analyzer 2 | 1920x1080@59.94 | 59.93 >> | Analyzer 2 | 1920x180@60 | 60 >> | Analyzer 2 | 3840x2160@23.98 | 23.97 >> | Analyzer 2 | 3840x2160@24 | 24 >> | Analyzer 2 | 3840x2160@29.97 | 29.96 >> | Analyzer 2 | 3840x2160@30 | 30 >> | Analyzer 2 | 3840x2160@59.94 | 59.93 >> | Analyzer 2 | 3840x2160@60 | 60 > Nice! > > Are the sources with a bad clock included in these results? I only see deviations > of 0.02 at most, so I don't think so. The results include all the sources I have to test (Player x indicates a real player available in the market while Analyzer x indicates HDMI protocol analyzer). From the data I've collected the players are the ones with the less precise clock, thats what I was referring as a bad clock. But even with that deviations the algorithm computes the value ok. I think I don't have any player else to test here. Maybe, if you could, test the patch series with cobalt + adv with a player and check the precision? ( I think cobalt uses an adv as subdev, right? ) > >> ------------------------------------------------------------------------------ >> >> What do you think? Shall we continue integrating this new patch >> or drop it? > Yes, we can continue. This is what I wanted to know :-) > Thank you for testing this, much appreciated. No problem :) Please review the patch series (when you can) so that I can submit a next version. Best regards, Jose Miguel Abreu > > Regards, > > Hans
