+#include "mdct.h"
+
+#define VE_PRE 16
+#define VE_WIN 4
+#define VE_POST 2
+#define VE_AMP (VE_PRE+VE_POST-1)
+
+#define VE_BANDS 7
+#define VE_NEARDC 15
+
+#define VE_MINSTRETCH 2 /* a bit less than short block */
+#define VE_MAXSTRETCH 12 /* one-third full block */
+
+typedef struct {
+ float ampbuf[VE_AMP];
+ int ampptr;
+
+ float nearDC[VE_NEARDC];
+ float nearDC_acc;
+ float nearDC_partialacc;
+ int nearptr;
+
+} envelope_filter_state;
+
+typedef struct {
+ int begin;
+ int end;
+ float *window;
+ float total;
+} envelope_band;