[FFmpeg-devel] Support for dumping pgx for JPEG2000

[Carl Eugen Hoyos]

Am Mo., 22. Juni 2020 um 20:44 Uhr schrieb Gautam Ramakrishnan
<gautamramk at gmail.com>:

> Another issue is that as the .pgx format is tightly linked to JPEG2000,
> how could the format be restricted to conversions between j2k and jp2
> files only?

For the sake of this discussion, pgx has absolutely nothing to do with
j2k, and the decoder you suggested to create can especially not be
used to do any conversion from or to j2k or jp2, it can only be used
to read pgx files (I am all for unusual formats in FFmpeg but an
encoder for this format seems of little value).

> For example, the pgx header contains a field called signed, which
> indicates whether the component values are signed or unsigned.

Yes, and when implementing the decoder you have to keep this
field in mind.

> This seems very specific to jpeg2000 and would not probably
> allow conversion from pgx to other formats directly.

No, that's not correct / ask again when you get to a point where this
is an issue.

Carl Eugen