[FFmpeg-devel] [PATCH 08/21] fftools/ffmpeg_filter: add filtergraph private data

[James Almer]

On 4/28/2023 5:45 AM, Nicolas George wrote:
> Anton Khirnov (12023-04-27):
>> Start by moving OutputStream.filtered_frame to it, which really belongs
>> to the filtergraph rather than the output stream.
> 
> Then just move them to OutputStream. This is just code noise for no
> practical benefit, since ffmpeg is not a library and does not have to
> deal with ABI stability or types declared in private headers.

The longtime goal of this work is to have completely standalone modules 
within the CLI and each of them threaded. So while ffmpeg may not be a 
library, clearly defining what fields should be accessed from "the 
outside" and which shouldn't would have the same effect and benefits as 
if it was one, particularly ensuring no future accidental usage of 
fields that should not be touched. The decoder side for example has no 
need to touch a frame the filtering side is using internally, and more 
so if it could result in races.

There's also the fact Anton is maintaining this code and this helps him 
keep track of the nature of each field, plus the fact this same change 
has been done before elsewhere, so if you're going to argue you don't 
like it because in your opinion it's unnecessary, then that's not enough 
grounds to block it.