added audio_out_format_bits to calc len alignment

git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@6027 b3059339-0415-0410-9bf9-f77b7e298cf2

libao2/afmt.c

@@ -45,3 +45,40 @@ char *audio_out_format_name(int format)
     }
     return("Unknown");
 }
+
+// return number of bits for 1 sample in one channel, or 8 bits for compressed
+int audio_out_format_bits(int format){
+    switch (format)
+    {
+/*
+  the following two formats are not available with old linux kernel
+  headers (e.g. in 2.2.16)
+*/
+#ifdef AFMT_S32_LE
+	case AFMT_S32_LE:
+	return 32;
+#endif
+#ifdef AFMT_S32_BE
+	case AFMT_S32_BE:
+	return 32;
+#endif
+
+	case AFMT_U16_LE:
+	case AFMT_U16_BE: 
+	case AFMT_S16_LE:
+	case AFMT_S16_BE:
+	return 16;//16 bits
+	
+	case AFMT_MU_LAW:
+	case AFMT_A_LAW:
+	case AFMT_IMA_ADPCM:
+	case AFMT_S8:
+	case AFMT_U8:
+	case AFMT_MPEG:
+	case AFMT_AC3:
+	default:
+	    return 8;//default 1 byte
+	
+    }
+    return 8;
+}

libao2/audio_out.h

@@ -42,6 +42,7 @@ extern ao_data_t ao_data;
 
 // prototypes
 extern char *audio_out_format_name(int format);
+extern int   audio_out_format_bits(int format);
 
 // NULL terminated array of all drivers
 extern ao_functions_t* audio_out_drivers[];