shithub: choc

Info  •  Files  •  Log  •  Branches

Make use_libsamplerate be an integer value that controls conversion
quality, rather than an on/off setting.

Subversion-branch: /trunk/chocolate-doom
Subversion-revision: 1112

--- a/src/i_sdlsound.c

+++ b/src/i_sdlsound.c

@@ -39,6 +39,7 @@

 #endif

 #include "deh_main.h"

+#include "i_system.h"

 #include "s_sound.h"

 #include "m_argv.h"

 #include "w_wad.h"

@@ -93,6 +94,33 @@

 #ifdef HAVE_LIBSAMPLERATE

+// Returns the conversion mode for libsamplerate to use.

+

+static int SRC_ConversionMode(void)

+{

+    switch (use_libsamplerate)

+    {

+        // 0 = disabled

+

+        default:

+        case 0:

+            return -1;

+

+        // Ascending numbers give higher quality

+

+        case 1:

+            return SRC_LINEAR;

+        case 2:

+            return SRC_ZERO_ORDER_HOLD;

+        case 3:

+            return SRC_SINC_FASTEST;

+        case 4:

+            return SRC_SINC_MEDIUM_QUALITY;

+        case 5:

+            return SRC_SINC_BEST_QUALITY;

+    }

+}

+

 // libsamplerate-based generic sound expansion function for any sample rate

 //   unsigned 8 bits --> signed 16 bits

 //   mono --> stereo

@@ -132,7 +160,7 @@

     // Do the sound conversion

-    retn = src_simple(&src_data, SRC_SINC_BEST_QUALITY, 1);

+    retn = src_simple(&src_data, SRC_ConversionMode(), 1);

     assert(retn == 0);

     // Convert the result back into 16-bit integers.

@@ -614,14 +642,20 @@

     Mix_QuerySpec(&mixer_freq, &mixer_format, &mixer_channels);

 #ifdef HAVE_LIBSAMPLERATE

-    if (use_libsamplerate)

+    if (use_libsamplerate != 0)

     {

+        if (SRC_ConversionMode() < 0)

+        {

+            I_Error("I_SDL_InitSound: Invalid value for use_libsamplerate: %i",

+                    use_libsamplerate);

+        }

+

         ExpandSoundData = ExpandSoundData_SRC;

         I_PrecacheSounds();

     }

 #else

-    if (use_libsamplerate)

+    if (use_libsamplerate != 0)

     {

         fprintf(stderr, "I_SDL_InitSound: use_libsamplerate=%i, but "

                         "libsamplerate support not compiled in.\n",

--- a/src/m_config.c

+++ b/src/m_config.c

@@ -697,9 +697,16 @@

     CONFIG_VARIABLE_INT(dclick_use,                dclick_use),

     //!

-    // If non-zero, libsamplerate is used to resample sound effects to

-    // the output sample rate.  This has no effect if libsamplerate

-    // support has not been compiled into the game.

+    // Controls whether libsamplerate support is used for performing

+    // sample rate conversions of sound effects.  Support for this

+    // must be compiled into the program.

+    //

+    // If zero, libsamplerate support is disabled.  If non-zero, 

+    // libsamplerate is enabled. Increasing values roughly correspond

+    // to higher quality conversion; the higher the quality, the 

+    // slower the conversion process.  Linear conversion = 1; 

+    // Zero order hold = 2; Fast Sinc filter = 3; Medium quality

+    // Sinc filter = 4; High quality Sinc filter = 5.

     //

     CONFIG_VARIABLE_INT(use_libsamplerate,         use_libsamplerate),