[FFmpeg-devel] [PATCH 1/2 v3] lavf/isom: add Dolby Vision sample entry codes for HEVC and H.264

[Carl Eugen Hoyos]

2018-12-18 18:38 GMT+01:00, Jan Ekström <jeebjp at gmail.com>:
> On Tue, Dec 18, 2018 at 7:30 PM Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
>>
>> 2018-12-18 18:24 GMT+01:00, Jan Ekström <jeebjp at gmail.com>:
>> > On Tue, Dec 18, 2018 at 7:21 PM Carl Eugen Hoyos <ceffmpeg at gmail.com>
>> > wrote:
>> >>
>> >> 2018-12-18 18:17 GMT+01:00, Jan Ekström <jeebjp at gmail.com>:
>> >> > On Mon, Dec 17, 2018 at 10:17 PM Jan Ekström <jeebjp at gmail.com>
>> >> > wrote:
>> >> >>
>> >> >> On Mon, Dec 17, 2018 at 3:47 PM Carl Eugen Hoyos
>> >> >> <ceffmpeg at gmail.com>
>> >> >> wrote:
>> >> >> >
>> >> >> > 2018-12-17 7:58 GMT+01:00, Jan Ekström <jeebjp at gmail.com>:
>> >> >> > > On Mon, Dec 17, 2018, 03:02 Carl Eugen Hoyos <ceffmpeg at gmail.com
>> >> >> > > wrote:
>> >> >> > >
>> >> >> > >> 2018-12-17 1:58 GMT+01:00, Jan Ekström <jeebjp at gmail.com>:
>> >> >> >
>> >> >> > >> > So as far as it's been possible to test this, that's been
>> >> >> > >> > done
>> >> >> > >>
>> >> >> > >> Could you point me to a dva1 sample?
>> >> >> > >
>> >> >> > > I have not seen any dolby vision samples with avc in the wild.
>> >> >> > > You can ask Vittorio if he has some as he noted about
>> >> >> > > possibly being able to ask for some before.
>> >> >> >
>> >> >> > The patch is of course ok if Vittorio tested it with his samples.
>> >> >> >
>> >> >> > Thank you, Carl Eugen
>> >> >>
>> >> >> Unfortunately I have no idea what samples Vittorio does or does not
>> >> >> possess, he has only mentioned off-hand that he might able to get
>> >> >> hold
>> >> >> of some if required. And since you were the one requiring them, I
>> >> >> pointed you towards him.
>> >> >>
>> >> >> For myself, I am happy with the following points regarding this:
>> >> >> 1. The identifiers are registered at the MPEG-4 RA.
>> >> >> 2. There is a proper specification for these mappings that is
>> >> >> seemingly kept up-to-date.
>> >> >> 3. The mappings specification specifically notes that the only
>> >> >> difference between the AVC and HEVC identifiers are the semantics
>> >> >> mentioned in ISO/IEC 14496-15. We already have all of the
>> >> >> identifiers
>> >> >> specified which these mappings are based upon, so those semantics
>> >> >> should not matter to us (and if they do, we have already broken
>> >> >> those
>> >> >> constraints at this point).
>> >> >> 4. The mapping specification specifically notes that the given AVC
>> >> >> and
>> >> >> HEVC identifiers must also include the standard avcC and hvcC boxes
>> >> >> so
>> >> >> that they can be decoded normally without any additional custom
>> >> >> code.
>> >> >> 5. We have samples for at least one of the four identifiers that
>> >> >> matches points 1 to 4.
>> >> >> 6. Android, Chromium, VLC among others have already implemented
>> >> >> these
>> >> >> identifiers in the same way.
>> >> >>
>> >> >> Now, if you are not happy with these points, then please clearly
>> >> >> state
>> >> >> that you are blocking any and all additional identifier additions -
>> >> >> no
>> >> >> matter how specified - as long as there are no samples on hand for
>> >> >> them.
>> >> >
>> >> > After taking a second look at this sentence, I find this wording
>> >> > being
>> >> > loaded and antagonizing. It was unprofessional, and I apologize for
>> >> > it.
>> >> >
>> >> > But the wish underneath was to get a clear view into what it was it
>> >> > that you wanted. That was what was mostly clouded for me in your
>> >> > replies, and that annoyed me to no end.
>> >> >
>> >> > While I must say that I would have been happy if you had told me you
>> >> > were not blocking the patch (set), I did not want a specific outcome
>> >> > out of this sentence. I just wanted you to voice your level of
>> >> > discomfort with the patch (set) and to voice your current wishes
>> >> > regarding it. I had set my wishes on the table with the six points,
>> >> > and why I believed the patch (set) was fine as it was.
>> >> >
>> >> > That is why after I wrote this post I asked Michael what it was that
>> >> > was the procedure for cases where developers have seemingly
>> >> > irreconcilable differences in opinions regarding a patch set. I did
>> >> > not know if that was the case, but the main point was that in the
>> >> > unfortunate case that the patch was blocked, and we did not agree on
>> >> > some points heavily enough that we could not co-operate, that the
>> >> > next
>> >> > step could be taken right away so as to not have the patch (set) sit
>> >> > there untouched for another week or two.
>> >> >
>> >> > Unfortunately, you did not respond to or touch this sentence at all,
>> >> > which I then interpreted as your comments not being blockers.
>> >>
>> >> > I hope this makes my intentions and annoyances clear.
>> >>
>> >> Afaict, it contradicts what you wrote on irc yesterday.
>> >>
>> >> > I hope that in
>> >> > the future we can continue to co-operate, and that this makes it
>> >> > clear
>> >> > that I do not have any personal grievances nor a vendetta against
>> >> > you.
>> >>
>> >> Carl Eugen
>> >
>> > Feel free to quote the parts that you think contradict.
>>
>> I was under the assumption you had read this:
>> [21:26:03 CET] <durandal_1707> carl just officially approved your
>> patch with single condition to mention ticket #7347
>>
>> But re-reading it, there was no indication you actually understood
>> what Paul wrote (or even read it), so sorry if I was wrong.
>>
>
> Yes, that specific line I had no interest in. I was tired, and the
> ticket was not in my opinion getting fixed with this, as only after we
> got the Dolby Vision profile 5 color space reverse engineered would we
> actually have these clips properly playing (outside of hardware
> decoding paths specifically meant for Dolby Vision). I had commented
> in a way on the mailing list thread towards that e-mail that I thought
> made it clear that I would not be adding the ticket identifier

> (esp. not at the eleventh hour, which it really did feel like to me at that
> point).

No, November 6th is not the eleventh hour.

> For the record, me and Rodger had already worked on grasping what
> standard ICtCp was on the mpv development channel (and Rodger with
> Niklas already had a patch around which I still have had not the time
> to review on that side of open source), and that seemed to not be the
> thing (so the marketing text in Dolby's specification about it being
> proprietary in some way was not a lie).

Carl Eugen