[FFmpeg-user] decoding jpeg2000 problem

[Carles Vila]

On 4 September 2015 at 15:45, Paul B Mahol <onemda at gmail.com> wrote:

> On 9/4/15, Carl Eugen Hoyos <cehoyos at ag.or.at> wrote:
> > Carles Vila <cvilad <at> gmail.com> writes:
> >
> >> Here's the command line. I had to include
> >> -pix_fmt xyz12le in order to have it detect
> >> xyz of the jpeg2000.
> >> However, the output still looks posterized.
> >
> > I am not sure if I understand the word posterized,
> > but concerning "still" the output looks very
> > different here if I omit -pix_fmt xyz12
>
> Compare native decoder output with one from ImageMagick.
>
> >
> > Carl Eugen
> >
> > _______________________________________________
> > ffmpeg-user mailing list
> > ffmpeg-user at ffmpeg.org
> > http://ffmpeg.org/mailman/listinfo/ffmpeg-user
> >
> _______________________________________________
> ffmpeg-user mailing list
> ffmpeg-user at ffmpeg.org
> http://ffmpeg.org/mailman/listinfo/ffmpeg-user
>

Hi Carl Eugen,
Sorry, I'm not explaining too clearly.
If I omit -pix_fmt xyz12 the output looks weird (greenish) because no
colour transformation is done. This is absolutely normal.

If I include -pix_fmt xyz12, the colours are OK, but the dark levels seem
posterized.

by posterized I mean this: https://svi.nl/PosterizationArtifacts
Let me know if you see it too, it is particularly obvious at the very
beginning, when the blue light comes in.

What I wanted to point out is that in the output which is not
color-transformed, this artifact is less noticeable.
Thanks