[PATCH v2] winegstreamer: Ensure that the source reports both PCM and floating point audio formats.

[Nikolay Sivov]

On 5/13/21 10:47 AM, Giovanni Mascellani wrote:
> Hi,
>
> Il 13/05/21 09:18, Nikolay Sivov ha scritto:
>> On 5/12/21 6:37 PM, Giovanni Mascellani wrote:
>>> diff --git a/dlls/winegstreamer/media_source.c
>>> b/dlls/winegstreamer/media_source.c
>>> index eb5b9e366ec..5249bc9c41d 100644
>>> --- a/dlls/winegstreamer/media_source.c
>>> +++ b/dlls/winegstreamer/media_source.c
>>> @@ -806,6 +806,31 @@ static HRESULT media_stream_init_desc(struct
>>> media_stream *stream)
>>>                   goto done;
>>>           }
>>>       }
>>> +    else if (format.major_type == WG_MAJOR_TYPE_AUDIO)
>>> +    {
>>> +        /* Expose at least one PCM and one floating point type for the
>>> +           consumer to pick from. */
>>> +        static const enum wg_audio_format audio_types[] =
>>> +        {
>>> +            WG_AUDIO_FORMAT_S16LE,
>>> +            WG_AUDIO_FORMAT_F64LE,
>>> +        };
>> Is F64LE correct? I thought before you used an equivalent of F32LE, if
>> that's what (Float, MF_MT_AUDIO_BITS_PER_SAMPLE=32) means.
>
> Ugh, I meant F32LE. My mistake.
>
>>> +
>>> +        stream_types = malloc( sizeof(IMFMediaType *) *
>>> (ARRAY_SIZE(audio_types) + 1) );
>>> +
>>> +        stream_types[0] = mf_media_type_from_wg_format(&format);
>>> +        type_count = 1;
>>> +
>>> +        for (i = 0; i < ARRAY_SIZE(audio_types); i++)
>>> +        {
>>> +            struct wg_format new_format;
>>> +            if (format.u.audio.format == audio_types[i])
>>> +                continue;
>>> +            new_format = format;
>>> +            new_format.u.audio.format = audio_types[i];
>>> +            stream_types[type_count++] =
>>> mf_media_type_from_wg_format(&new_format);
>>> +        }
>>> +    }
>>>       else
>>>       {
>>>           stream_type = mf_media_type_from_wg_format(&format);
>> Thanks, that looks fine to me. It could be reduced a bit more still, by
>> removing 'new_format' for example, but that's minor.
>
> That would be wrong, wouldn't it? If I change format.u.audio.format,
> then the "if () continue" at the beginning of the loop doesn't make
> sense any more. Unless I remember the original format in another
> variable, which would then have comparable complexity.
>
>>   Now we need someone
>> who knows gstreamer to comment, specifically if resampling PCM ->
>> PCM/float -> float would work. Or maybe you can test that yourself with
>> some sin wave data with rate not matching output device rate.
>
> I can't see how this is related to my patch: I don't think Gstreamer
> does any rate change at this level. It just advertises the native rate
> the audio stream supports. Whatever rate matching is required, it will
> be done downstream from the media source (both before and after my
> patch, which is only concerned with the sample format, not its rate).
Original patch added PCM->F32LE and float->S16LE conversions, this one
also adds conversions between different PCM and different float formats.
So the question is does it work? It was wrong to call it rate, I meant
bps of course, or format as whole.
>
> Thanks, Giovanni.
>