[FFmpeg-devel] [PATCH v4] avcodec/pngdec: read colorspace info when decoding with AVDISCARD_ALL

[Ronald S. Bultje]

Hi,

On Tue, Feb 21, 2023 at 5:36 PM Leo Izen <leo.izen at gmail.com> wrote:

> These chunks are lightweight and it's useful information to have when
> running ffmpeg -i or ffprobe, for example.
>

I disagree conceptually with this. If we want to skip "all" decoding, we
should also skip metadata for said frames.

I think what we're looking for here is a partial decoding stage, e.g.
"header-only" or similar, instead of "including framedata", for some or all
frames. That's orthogonal to AVDISCARD_*.

Ronald