add replayGain stuff for flac from AliasMrJones

git-svn-id: https://svn.musicpd.org/mpd/trunk@943 09075e82-0dd4-0310-85a5-a0d7c8717e4f

1 files changed, 80 insertions, 0 deletions

diff --git a/src/replayGain.c b/src/replayGain.c
new file mode 100644
index 000000000..ece583a06
--- /dev/null
+++ b/src/replayGain.c
@@ -0,0 +1,80 @@
+
+#include "replayGain.h"
+
+#include "log.h"
+#include "conf.h"
+
+#include <string.h>
+#include <math.h>
+#include <stdlib.h>
+ 
+/* Added 4/14/2004 by AliasMrJones */
+static int replayGainState = REPLAYGAIN_OFF;
+
+void initReplayGainState() {
+	if(!getConf()[CONF_REPLAYGAIN]) return;
+
+	if(strcmp(getConf()[CONF_REPLAYGAIN],"track")==0) {
+		replayGainState = REPLAYGAIN_TRACK;
+	}
+	else if(strcmp(getConf()[CONF_REPLAYGAIN],"album")==0) {
+		replayGainState = REPLAYGAIN_ALBUM;
+	}
+	else {
+		ERROR("replaygain value \"%s\" is invalid\n",
+				getConf()[CONF_REPLAYGAIN]);
+		exit(EXIT_FAILURE);
+	}
+}
+
+int getReplayGainState() {
+	return replayGainState;
+}
+
+float computeReplayGainScale(float gain, float peak){
+	float scale;
+
+	if(gain == 0.0) return(1);
+	scale = pow(10.0, gain/20.0);
+	if(scale > 15.0) scale = 15.0;
+
+	if (scale * peak > 1.0) {
+		scale = 1.0 / peak;
+	}
+	return(scale);
+}
+
+void doReplayGain(char * buffer, int bufferSize, AudioFormat * format, 
+		float scale) 
+{
+	mpd_sint16 * buffer16 = (mpd_sint16 *)buffer;
+	mpd_sint8 * buffer8 = (mpd_sint8 *)buffer;
+	mpd_sint32 temp32;
+
+	if(scale == 1.0) return;
+	switch(format->bits) {
+		case 16:
+			while(bufferSize > 0){
+				temp32 = *buffer16;
+				temp32 *= scale;
+				*buffer16 = temp32>32767 ? 32767 : 
+					(temp32<-32768 ? -32768 : temp32);
+				buffer16++;
+				bufferSize-=2;
+			}
+			break;
+		case 8:
+			while(bufferSize>0){
+				temp32 = *buffer8;
+				temp32 *= scale;
+				*buffer8 = temp32>127 ? 127 : 
+					(temp32<-128 ? -128 : temp32);
+				buffer8++;
+				bufferSize--;
+			}
+			break;
+		default:
+			ERROR("%i bits not supported by doReplaygain!\n", format->bits);
+	}
+}
+/* End of added code */