Add fade in/out to the sound tests

[Francois Gouget]

Running the winmm test on a laptop in Windows XP I got loud pops between 
each test tone. It's not really a big problem. It just distracts testers 
from the real problems. I don't think this is an issue with the sound 
driver. It's more likely bad electronics which is unable to properly 
control the even worse speakers.

So I added a simple 1/100 second linear fade in and fade out to each 
test tone and this eliminated the pops for all tests with a sampling 
rate >22050Hz, and significatly reduced them for the 11025Hz tests.

So I propose to just make this fade in/fade out standard in our test 
tones but I'm open to suggestions.


Changelog:

  * dlls/dsound/tests/dsound.c
    dlls/winmm/tests/wave.c

    Francois Gouget <fgouget at codeweavers.com>
    Add a 1/100 second fade in/out to reduce the pops between the test 
tones.


-- 
Francois Gouget
fgouget at codeweavers.com

-------------- next part --------------
Index: dlls/dsound/tests/dsound.c
===================================================================
RCS file: /var/cvs/wine/dlls/dsound/tests/dsound.c,v
retrieving revision 1.20
diff -u -r1.20 dsound.c
--- a/dlls/dsound/tests/dsound.c	20 Jan 2004 21:49:48 -0000	1.20
+++ b/dlls/dsound/tests/dsound.c	18 May 2004 21:38:12 -0000
@@ -73,16 +73,21 @@
 #define PI 3.14159265358979323846
 static char* wave_generate_la(WAVEFORMATEX* wfx, double duration, DWORD* size)
 {
-    int i;
+    int i,fade;
     int nb_samples;
     char* buf;
     char* b;
 
+    fade=wfx->nSamplesPerSec/100;
     nb_samples=(int)(duration*wfx->nSamplesPerSec);
     *size=nb_samples*wfx->nBlockAlign;
     b=buf=malloc(*size);
     for (i=0;i<nb_samples;i++) {
 	double y=sin(440.0*2*PI*i/wfx->nSamplesPerSec);
+        if (i<fade)
+            y=y*i/fade;
+        else if (nb_samples-i<fade)
+            y=y*(nb_samples-1-i)/fade;
 	if (wfx->wBitsPerSample==8) {
 	    unsigned char sample=(unsigned char)((double)127.5*(y+1.0));
 	    *b++=sample;
Index: dlls/winmm/tests/wave.c
===================================================================
RCS file: /var/cvs/wine/dlls/winmm/tests/wave.c,v
retrieving revision 1.22
diff -u -r1.22 wave.c
--- a/dlls/winmm/tests/wave.c	14 May 2004 04:54:54 -0000	1.22
+++ b/dlls/winmm/tests/wave.c	18 May 2004 22:07:03 -0000
@@ -73,16 +54,21 @@
 #define PI 3.14159265358979323846
 static char* wave_generate_la(WAVEFORMATEX* wfx, double duration, DWORD* size)
 {
-    int i;
+    int i,fade;
     int nb_samples;
     char* buf;
     char* b;
 
-    nb_samples=(int)(duration*wfx->nSamplesPerSec);
+    fade=wfx->nSamplesPerSec/100;
+    nb_samples=(int)(duration*wfx->nSamplesPerSec)+1;
     *size=nb_samples*wfx->nBlockAlign;
     b=buf=malloc(*size);
     for (i=0;i<nb_samples;i++) {
         double y=sin(440.0*2*PI*i/wfx->nSamplesPerSec);
+        if (i<fade)
+            y=y*i/fade;
+        else if (nb_samples-i<fade)
+            y=y*(nb_samples-1-i)/fade;
         if (wfx->wBitsPerSample==8) {
             unsigned char sample=(unsigned char)((double)127.5*(y+1.0));
             *b++=sample;