[vlc-devel] [PATCH 16/16] wasapi: handle AUDIO_CHANNELS_TYPE_AMBISONICS

[Thomas Guillem]

---
 modules/audio_output/wasapi.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/modules/audio_output/wasapi.c b/modules/audio_output/wasapi.c
index e4803b2c6f..948deb24eb 100644
--- a/modules/audio_output/wasapi.c
+++ b/modules/audio_output/wasapi.c
@@ -480,9 +480,25 @@ static HRESULT Restart(aout_stream_t *s, audio_sample_format_t *restrict pfmt,
     AUDCLNT_SHAREMODE shared_mode;
     REFERENCE_TIME buffer_duration;
     audio_sample_format_t fmt = *pfmt;
-
+    bool low_latency = false;
     bool b_spdif = AOUT_FMT_SPDIF(&fmt);
     bool b_hdmi = AOUT_FMT_HDMI(&fmt);
+
+    if (fmt.channels_type == AUDIO_CHANNELS_TYPE_AMBISONICS)
+    {
+        fmt.channels_type = AUDIO_CHANNELS_TYPE_PHYSICAL;
+        assert(!b_spdif && !b_hdmi);
+
+        /* Request the maximum numbers of channels. The closest channel
+         * configuration will be used to configure ambisonics filters */
+        fmt.i_original_channels = fmt.i_physical_channels = AOUT_CHANS_7_1;
+        aout_FormatPrepare(&fmt);
+
+        /* Setup low latency in order to quickly react to ambisonics filters
+         * viewpoint changes. */
+        low_latency = true;
+    }
+
     if (b_spdif && !b_hdmi && fmt.i_format == VLC_CODEC_DTS && !force_dts_spdif
      && fmt.i_rate >= 48000)
     {
@@ -512,7 +528,8 @@ static HRESULT Restart(aout_stream_t *s, audio_sample_format_t *restrict pfmt,
     {
         vlc_ToWave(pwfe, &fmt);
         shared_mode = AUDCLNT_SHAREMODE_SHARED;
-        buffer_duration = AOUT_MAX_PREPARE_TIME * 10;
+        buffer_duration = (low_latency ? AOUT_MIN_PREPARE_TIME
+                                       : AOUT_MAX_PREPARE_TIME) * 10;
     }
     else
     {
-- 
2.11.0