Re: MesaLib mpeg12 bug: lack of samples

[tlaronde%kergis.com@localhost]

On Sat, Dec 09, 2023 at 08:35:34PM +0100, tlaronde%kergis.com@localhost wrote:
> At least xine(1) and vlc(1) crashes, in various circumstances (xine(1)
> directly if invoked without argument; vlc(1) when trying to read a
> dvd) but the failure in both cases comes from MesaLib, gallium,
> namely, in MesaLib sources:
> 
> src/gallium/auxiliary/vl/vl_mpeg12_decoder.c
> 
> There are functions (not procedures) but treated like procedures i.e.
> the return value is in fact ignored, taken as granted with assertions
> being used to catch the failing cases by aborting.
> 
> And it aborts.
> 
> The problem is that a buffer is initted (guessing by the names),
> from samples. 3 planes are expected (a guess once more: red,
> green, blue in whatever order) but in my case there is only sample (one
> plane).
> 
> 	=> My screen has pixel depth = 16 bits stored in 2 bytes.
> 	XXX I should try if going 24 bits exhibit the problem or not...
> 
>[...]

Switching to 24 bits doesn't circumvent the problem but there is a
difference in behavior:

At the moment:

- xine(1) crashes at whatever depth when invoked without argument
because it tries to display the logo: "xine --no-logo" passes this and
doesn't crash at least then. If invoked with a mp4 file: at 16bits,
sound is here but no image; at 24 bits, rendering... In all cases,
unable to play a DVD (crashes): bug in MesaLib/gallium, at least
with radeon r600 driver;

- vlc(1): doesn't crash when invoked without argument. Renders mp4 at
whatever depth (16 bits or 24 bits). Unable to play a DVD (crashes):
bug in MesaLib/gallium, at least with radeon r600 driver;

- ogle(1): able to play a DVD since it doesn't use "new" stuff...

-- 
        Thierry Laronde <tlaronde +AT+ kergis +dot+ com>
                     http://www.kergis.com/
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