[FFmpeg-devel] query on pixel formats

[Carl Eugen Hoyos]

Am Mi., 17. Juni 2020 um 13:00 Uhr schrieb Gautam Ramakrishnan
<gautamramk at gmail.com>:
>
> Hi all,
>
> I am working on the JPEG2000 decoder. However I am having trouble
> understanding pixel formats correctly.
> For example, from my understanding, the reference file p1_01.j2k pixel
> format does not get recognized by the native decoder. When I force a
> gray8 format on it, I am able to get output similar to opj_decompress

> (I have made other modifications to the decoder as well).

Please post them together with your question.

> It would be great if I could be referred to some documentation which
> would help me understand how exactly the pixel format selection works.

See pix_fmt_match(), called from get_siz() and find out why
gray was not chosen.
(A wild guess is that gray8 has to be added to RGB_PIXEL_FORMATS)

Carl Eugen