[FFmpeg-devel] [PATCH] make img_convert symbol conditional on lavc version, not libswscale

Anssi Hannula anssi.hannula
Thu Jun 5 20:09:58 CEST 2008

Reinhard Tartler wrote:
> Michael Niedermayer <michaelni at gmx.at> writes:
>>> Is enabling img_convert really a problem?  Can't the scalers be used
>>> side by side?
>> Its duplicated code and bloat at least and as said i do not know if it works
>> at all.
> Duplicated code bloat is in general not an issue for general purpose
> distributions. I acklowledge that it does matter on embedded devices.
> Providing both scaler seems to work in at least mandriva and
> Debian. I've noticed that if done like in mandriva, both libavcodec and
> libswscale provide the following symbols with the same name:
>  - sws_getCachedContext
>  - sws_getContext
>  - sws_freeContext
>  - sws_scale.
> For all corresponding function I've checked that they feature the same
> signature, but provide a different implementation. I've therfore decided
> to disable the implementation in libavcodecs img_resaple.c for
> Debian.

I'll make this change to the Mandriva patch as well.

> I think if these four functions where conditionally compiled (only
> without libswscale) in libavcodec, it would be reasonable to apply that
> patch to ffmpeg upstream as transition help for downstreams.

Yeah, package maintainers usually do not have time to learn APIs and
port applications between them. That is left to the upstream developers.

I don't care that much whether the old api should be provided in
upstream ffmpeg, though. It is, after all, a deprecated api.

Anssi Hannula

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