[FFmpeg-devel] Support for dumping pgx for JPEG2000

[Carl Eugen Hoyos]

Am Mo., 22. Juni 2020 um 20:08 Uhr schrieb Gautam Ramakrishnan
<gautamramk at gmail.com>:
>
> On Mon, Jun 22, 2020 at 11:30 PM Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
> >
> > Am Mo., 22. Juni 2020 um 19:40 Uhr schrieb Gautam Ramakrishnan
> > <gautamramk at gmail.com>:
> > >
> > > On Mon, Jun 22, 2020 at 8:07 PM Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
> > > >
> > > >
> > > >
> > > > > Am 22.06.2020 um 12:42 schrieb Moritz Barsnick <barsnick at gmx.net>:
> > > > >
> > > > >> On Mon, Jun 22, 2020 at 12:47:11 +0530, Gautam Ramakrishnan wrote:
> > > > >> On Mon, Jun 22, 2020 at 12:38 PM Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
> > > > >>>> Am 22.06.2020 um 07:32 schrieb Gautam Ramakrishnan <gautamramk at gmail.com>:
> > > > >>>> JPEG2000 uses .pgx format for conformance testing. Is it a good idea
> > > > >>>> to allow the ffmpeg native decoder to have an option to dump .pgx files?
> > > > >>> I believe it would be more useful if FFmpeg could read pgx files.
> > > > >> So could a new Codec be created for reading and writing pgx files?
> > > > >
> > > > > Actually, probably a very simple demuxer/muxer, as the payload seems
> > > > > to be uncompressed/raw.
> > > >
> > > > Most likely a decoder as for pnm or tga.
> >
> > > I shall work on this. The format seems really simple. However,
> > > how do I make the encoder write multiple files and the decoder
> > > read multiple files? Each component would map to one .pgx file.
> >
> > You only read one of the files at a time, the extractplanes filter can
> > be used to compare the content.

> So what you mean to say is if I am given say 3 pgx files for r g and b
> components respectively, the decoder would not decode all of them into
> one image. But as this is a testing format and only for conformance testing,
> that should not be an issue?

(Please cut the mailing list footer from your quotes)

Let's not overengineer reading a format that has very little use.

Carl Eugen