[PATCH 2/2] dsound: Added 7.1 to stereo downmix

[Andrew Eikum]

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=46996
Signed-off-by: Andrew Eikum <aeikum at codeweavers.com>

On Tue, Apr 23, 2019 at 08:04:23PM +0200, Nikola Pavlica wrote:
> Signed-off-by: Nikola Pavlica <pavlica.nikola at gmail.com>
> ---
>  dlls/dsound/dsound_convert.c | 47 ++++++++++++++++++++++++++++++++++++
>  dlls/dsound/dsound_private.h |  1 +
>  dlls/dsound/mixer.c          |  6 +++++
>  3 files changed, 54 insertions(+)
> 
> diff --git a/dlls/dsound/dsound_convert.c b/dlls/dsound/dsound_convert.c
> index 0da9823298..db04ec1466 100644
> --- a/dlls/dsound/dsound_convert.c
> +++ b/dlls/dsound/dsound_convert.c
> @@ -251,6 +251,53 @@ void put_surround512stereo(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD c
>      }
>  }
>  
> +void put_surround712stereo(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel, float value)
> +{
> +    /* based on analyzing a recording of a dsound downmix */
> +    switch(channel){
> + 
> +    case 6: /* back left */
> +        value *= 0.24f;
> +        dsb->put_aux(dsb, pos, 0, value);
> +        break;
> +
> +    case 4: /* surround left */
> +        value *= 0.24f;
> +        dsb->put_aux(dsb, pos, 0, value);
> +        break;
> +
> +    case 0: /* front left */
> +        value *= 1.0f; 
> +        dsb->put_aux(dsb, pos, 0, value);
> +        break;
> +
> +    case 7: /* back right */
> +        value *= 0.24f;
> +        dsb->put_aux(dsb, pos, 1, value);
> +        break;
> +
> +    case 5: /* surround right */
> +        value *= 0.24f;
> +        dsb->put_aux(dsb, pos, 1, value);
> +        break;
> +
> +    case 1: /* front right */
> +        value *= 1.0f;
> +        dsb->put_aux(dsb, pos, 1, value);
> +        break;
> +
> +    case 2: /* centre */
> +        value *= 0.7;
> +        dsb->put_aux(dsb, pos, 0, value);
> +        dsb->put_aux(dsb, pos, 1, value);
> +        break;
> +
> +    case 3:
> +        /* LFE is totally ignored in dsound when downmixing to 2 channels */
> +        break;
> +    }
> +}
> +
>  void put_quad2stereo(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel, float value)
>  {
>      /* based on pulseaudio's downmix algorithm */
> diff --git a/dlls/dsound/dsound_private.h b/dlls/dsound/dsound_private.h
> index 45a100eee7..b04ce06275 100644
> --- a/dlls/dsound/dsound_private.h
> +++ b/dlls/dsound/dsound_private.h
> @@ -179,6 +179,7 @@ void put_stereo2quad(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel
>  void put_mono2surround51(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel, float value) DECLSPEC_HIDDEN;
>  void put_stereo2surround51(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel, float value) DECLSPEC_HIDDEN;
>  void put_surround512stereo(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel, float value) DECLSPEC_HIDDEN;
> +void put_surround712stereo(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel, float value) DECLSPEC_HIDDEN;
>  void put_quad2stereo(const IDirectSoundBufferImpl *dsb, DWORD pos, DWORD channel, float value) DECLSPEC_HIDDEN;
>  
>  HRESULT secondarybuffer_create(DirectSoundDevice *device, const DSBUFFERDESC *dsbd,
> diff --git a/dlls/dsound/mixer.c b/dlls/dsound/mixer.c
> index 32bde3800e..05ca99b5df 100644
> --- a/dlls/dsound/mixer.c
> +++ b/dlls/dsound/mixer.c
> @@ -179,6 +179,12 @@ void DSOUND_RecalcFormat(IDirectSoundBufferImpl *dsb)
>  		dsb->put = put_surround512stereo;
>  		dsb->put_aux = putieee32_sum;
>  	}
> +	else if (ichannels == 8 && ochannels == 2)
> +	{
> +		dsb->mix_channels = 8;
> +		dsb->put = put_surround712stereo;
> +		dsb->put_aux = putieee32_sum;
> +	}
>  	else if (ichannels == 4 && ochannels == 2)
>  	{
>  		dsb->mix_channels = 4;
> -- 
> 2.21.0
> 
> 
>