[PATCH 0/5] MR9583: dmusic: SF2 fixes, part 2

[PATCH 1/5] dmusic: Take coarse tune into account in instrument_add_soundfont_region().

[Anton Baskanov]

From: Anton Baskanov

---
 dlls/dmusic/instrument.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/dmusic/instrument.c b/dlls/dmusic/instrument.c
index 1710cbc690d..2c7bfc7862a 100644
--- a/dlls/dmusic/instrument.c
+++ b/dlls/dmusic/instrument.c
@@ -576,7 +576,7 @@ static HRESULT instrument_add_soundfont_region(struct instrument *This, struct s

unity_note = generators->amount[SF_GEN_OVERRIDING_ROOT_KEY].value;
     if (unity_note == (WORD)-1) unity_note = sample->original_key;
-    region->wave_sample.usUnityNote = unity_note;
+    region->wave_sample.usUnityNote = unity_note - (SHORT)generators->amount[SF_GEN_COARSE_TUNE].value;
     region->wave_sample.sFineTune = generators->amount[SF_GEN_FINE_TUNE].value;
     region->wave_sample.lAttenuation = sample->correction;

[PATCH 2/5] dmusic: Set attenuation based on SF_GEN_INITIAL_ATTENUATION.

[Anton Baskanov]

From: Anton Baskanov

---
 dlls/dmusic/instrument.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/dlls/dmusic/instrument.c b/dlls/dmusic/instrument.c
index 2c7bfc7862a..13f0434f677 100644
--- a/dlls/dmusic/instrument.c
+++ b/dlls/dmusic/instrument.c
@@ -18,6 +18,8 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
  */

+#include <math.h>
+
 #include "dmusic_private.h"
 #include "soundfont.h"
 #include "dls2.h"
@@ -563,6 +565,7 @@ static HRESULT instrument_add_soundfont_region(struct instrument *This, struct s
     UINT start_loop, end_loop, unity_note, sample_index = generators->amount[SF_GEN_SAMPLE_ID].value;
     struct sf_sample *sample = soundfont->shdr + sample_index;
     struct region *region;
+    double attenuation;

if (!(region = calloc(1, sizeof(*region)))) return E_OUTOFMEMORY;
     list_init(&region->articulations);
@@ -574,11 +577,15 @@ static HRESULT instrument_add_soundfont_region(struct instrument *This, struct s

region->wave_link.ulTableIndex = sample_index;

+    /* SF2 implementation for the original hardware applies a factor of 0.4 to
+     * the attenuation value. Although this does not comply with the SF2 spec,
+     * most soundfonts expect this behavior. */
+    attenuation = (SHORT)generators->amount[SF_GEN_INITIAL_ATTENUATION].value * 0.4;
     unity_note = generators->amount[SF_GEN_OVERRIDING_ROOT_KEY].value;
     if (unity_note == (WORD)-1) unity_note = sample->original_key;
     region->wave_sample.usUnityNote = unity_note - (SHORT)generators->amount[SF_GEN_COARSE_TUNE].value;
     region->wave_sample.sFineTune = generators->amount[SF_GEN_FINE_TUNE].value;
-    region->wave_sample.lAttenuation = sample->correction;
+    region->wave_sample.lAttenuation = (LONG)floor(attenuation * -65536. + 0.5);

start_loop = generators->amount[SF_GEN_STARTLOOP_ADDRS_OFFSET].value;
     start_loop += generators->amount[SF_GEN_STARTLOOP_ADDRS_COARSE_OFFSET].value * 32768;

[PATCH 3/5] dmusic: Add IIR filter resonance hump compensation.

[Anton Baskanov]

From: Anton Baskanov

---
 dlls/dmusic/instrument.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/dlls/dmusic/instrument.c b/dlls/dmusic/instrument.c
index 13f0434f677..ce8894ac835 100644
--- a/dlls/dmusic/instrument.c
+++ b/dlls/dmusic/instrument.c
@@ -581,6 +581,10 @@ static HRESULT instrument_add_soundfont_region(struct instrument *This, struct s
      * the attenuation value. Although this does not comply with the SF2 spec,
      * most soundfonts expect this behavior. */
     attenuation = (SHORT)generators->amount[SF_GEN_INITIAL_ATTENUATION].value * 0.4;
+    /* Normally, FluidSynth adds a resonance hump compensation in
+     * fluid_iir_filter_q_from_dB, but as DLS has no such compensation, it's
+     * disabled in the budled version of FluidSynth. Add it back here. */
+    attenuation += -15.05;
     unity_note = generators->amount[SF_GEN_OVERRIDING_ROOT_KEY].value;
     if (unity_note == (WORD)-1) unity_note = sample->original_key;
     region->wave_sample.usUnityNote = unity_note - (SHORT)generators->amount[SF_GEN_COARSE_TUNE].value;

[PATCH 4/5] dmusic: Add an 8 dB attenuation to normalize SF2 instrument volume.

[Anton Baskanov]

From: Anton Baskanov

---
 dlls/dmusic/instrument.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/dlls/dmusic/instrument.c b/dlls/dmusic/instrument.c
index ce8894ac835..fe1862dd4b0 100644
--- a/dlls/dmusic/instrument.c
+++ b/dlls/dmusic/instrument.c
@@ -585,6 +585,11 @@ static HRESULT instrument_add_soundfont_region(struct instrument *This, struct s
      * fluid_iir_filter_q_from_dB, but as DLS has no such compensation, it's
      * disabled in the budled version of FluidSynth. Add it back here. */
     attenuation += -15.05;
+    /* Add some attenuation to normalize the volume. The value was determined
+     * experimentally by comparing instruments from SF2 soundfonts to the
+     * gm.dls equivalents. The value is approximate, as there is some volume
+     * variation from instrument to instrument. */
+    attenuation += 80.;
     unity_note = generators->amount[SF_GEN_OVERRIDING_ROOT_KEY].value;
     if (unity_note == (WORD)-1) unity_note = sample->original_key;
     region->wave_sample.usUnityNote = unity_note - (SHORT)generators->amount[SF_GEN_COARSE_TUNE].value;

[PATCH 5/5] dmusic: Take sample correction into account.

[Anton Baskanov]

From: Anton Baskanov

---
 dlls/dmusic/instrument.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/dmusic/instrument.c b/dlls/dmusic/instrument.c
index fe1862dd4b0..99232998f0b 100644
--- a/dlls/dmusic/instrument.c
+++ b/dlls/dmusic/instrument.c
@@ -593,7 +593,7 @@ static HRESULT instrument_add_soundfont_region(struct instrument *This, struct s
     unity_note = generators->amount[SF_GEN_OVERRIDING_ROOT_KEY].value;
     if (unity_note == (WORD)-1) unity_note = sample->original_key;
     region->wave_sample.usUnityNote = unity_note - (SHORT)generators->amount[SF_GEN_COARSE_TUNE].value;
-    region->wave_sample.sFineTune = generators->amount[SF_GEN_FINE_TUNE].value;
+    region->wave_sample.sFineTune = sample->correction + generators->amount[SF_GEN_FINE_TUNE].value;
     region->wave_sample.lAttenuation = (LONG)floor(attenuation * -65536. + 0.5);

start_loop = generators->amount[SF_GEN_STARTLOOP_ADDRS_OFFSET].value;

[Rémi Bernon (＠rbernon)]

Rémi Bernon (@rbernon) commented about dlls/dmusic/instrument.c:
>  region->wave_link.ulTableIndex = sample_index;
>
> - /* SF2 implementation for the original hardware applies a factor of 0.4 to
> -
> * the attenuation value. Although this does not comply with the SF2 spec,
> -
> * most soundfonts expect this behavior. */
> - attenuation = (SHORT)generators->amount[SF_GEN_INITIAL_ATTENUATION].value * 0.4;
> unity_note = generators->amount[SF_GEN_OVERRIDING_ROOT_KEY].value;
> if (unity_note == (WORD)-1) unity_note = sample->original_key;
> region->wave_sample.usUnityNote = unity_note - (SHORT)generators->amount[SF_GEN_COARSE_TUNE].value;
> region->wave_sample.sFineTune = generators->amount[SF_GEN_FINE_TUNE].value;
> - region->wave_sample.lAttenuation = sample->correction;
> - region->wave_sample.lAttenuation = (LONG)floor(attenuation * -65536. + 0.5);

Is this really supposed to be rounding like that? It's kind of weird.

[Anton Baskanov (＠baskanov)]

On Tue Nov 25 10:57:06 2025 +0000, Rémi Bernon wrote:
> Is this really supposed to be rounding like that? It's kind of weird.

It's just rounding to a nearest integer. I can change it to a simple cast if it's confusing.

[Rémi Bernon (＠rbernon)]

On Tue Nov 25 11:57:43 2025 +0000, Anton Baskanov wrote:
> It's just rounding to a nearest integer. I can change it to a simple
> cast if it's confusing.

Well not exactly, it rounds (v + 0.5) towards -inf. If you actually want to round to nearest, you should use `round` I think.