Phil Pertermann's dB peak meter patch

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@2774 a1c6a512-1295-4272-9138-f99709370657

10 files changed, 1034 insertions, 98 deletions

diff --git a/apps/debug_menu.c b/apps/debug_menu.c
index 97db40ee7d..4dd98e0498 100644
--- a/apps/debug_menu.c
+++ b/apps/debug_menu.c
@@ -40,6 +40,7 @@
 #include "mpeg.h"
 #ifdef HAVE_LCD_BITMAP
 #include "widgets.h"
+#include "peakmeter.h"
 #endif
 
 /*---------------------------------------------------*/
@@ -1031,7 +1032,10 @@ bool debug_menu(void)
         { "View partitions", dbg_partitions },
 #ifdef HAVE_LCD_BITMAP
         { "View mpeg thread", dbg_mpeg_thread },
-#endif
+#ifdef PM_DEBUG
+        { "pm histogram", peak_meter_histogram},
+#endif /* PM_DEBUG */
+#endif /* HAVE_LCD_BITMAP */
     };
 
     m=menu_init( items, sizeof items / sizeof(struct menu_items) );
@@ -1042,4 +1046,3 @@ bool debug_menu(void)
 }
 
 #endif /* SIMULATOR */
-
diff --git a/apps/lang/english.lang b/apps/lang/english.lang
index 3f1eb6efb8..373e072395 100644
--- a/apps/lang/english.lang
+++ b/apps/lang/english.lang
@@ -866,6 +866,46 @@ desc: in the peak meter menu
 eng: "Units Per Read"
 new: 
 
+id: LANG_PM_PERFORMANCE
+desc: in the peak meter menu
+eng: "Performance"
+new:
+
+id: LANG_PM_HIGH_PERFORMANCE
+desc: in the peak meter menu
+eng: "High performance"
+new:
+
+id: LANG_PM_ENERGY_SAVER
+desc: in the peak meter menu
+eng: "Save energy"
+new:
+
+id: LANG_PM_SCALE
+desc: in the peak meter menu
+eng: "dBfs <-> linear"
+new:
+
+id: LANG_PM_DBFS
+desc: in the peak meter menu
+eng: "dBfs"
+new:
+
+id: LANG_PM_LINEAR
+desc: in the peak meter menu
+eng: "linear"
+new:
+
+id: LANG_PM_MIN
+desc: in the peak meter menu
+eng: "Minimum of range"
+new:
+
+id: LANG_PM_MAX
+desc: in the peak meter menu
+eng: "Maximum of range"
+new:
+
 id: LANG_BACKLIGHT_ON_WHEN_CHARGING
 desc: in display_settings_menu
 eng: "Backlight On When Plugged"
diff --git a/apps/recorder/peakmeter.c b/apps/recorder/peakmeter.c
index df7c672617..e1850a4bb0 100644
--- a/apps/recorder/peakmeter.c
+++ b/apps/recorder/peakmeter.c
@@ -46,24 +46,52 @@ static bool peak_meter_r_clip = false;
 static long peak_meter_clip_timeout_l;
 static long peak_meter_clip_timeout_r;
 
+static int  peak_meter_clip_hold;
+
+/* specifies the value range in peak volume values */
+unsigned short peak_meter_range_min;
+unsigned short peak_meter_range_max;
+
 /* if set to true clip timeout is disabled */
 static bool peak_meter_clip_eternal = false;
 
+static bool peak_meter_use_dbfs = true;
+
+
 #ifndef SIMULATOR
 static int peak_meter_src_l = MAS_REG_DQPEAK_L;
 static int peak_meter_src_r = MAS_REG_DQPEAK_R;
 #endif
 
 /* temporarily en- / disables peak meter. This is
-
    especially for external applications to detect 
-
    if the peak_meter is in use and needs drawing at all */
 bool peak_meter_enabled = true;
 
+/*
+bool peak_meter_use_thread = false;
+static char peak_meter_stack[DEFAULT_STACK_SIZE];
+*/
+/* used in wps.c to set the display frame rate of the peak meter */
+int peak_meter_fps = 20;
+
 static int peak_meter_l;
 static int peak_meter_r;
 
+static int peak_meter_hold = 1;
+static int peak_meter_release = 8;
+
+/* debug only */
+#ifdef PM_DEBUG
+static int peek_calls = 0;
+
+#define PEEKS_PER_DRAW_SIZE 40
+static unsigned int peeks_per_redraw[PEEKS_PER_DRAW_SIZE];
+
+#define TICKS_PER_DRAW_SIZE 20
+static unsigned int ticks_per_redraw[TICKS_PER_DRAW_SIZE];
+#endif
+
 /* time out values for max */
 static long max_time_out[] = {
     0 * HZ, HZ / 5, 30, HZ / 2, HZ, 2 * HZ, 
@@ -80,6 +108,353 @@ static long clip_time_out[] = {
     2700 * HZ, 5400 * HZ
 };
 
+/* precalculated peak values that represent magical
+   dBfs values. Used to draw the scale */
+#if 0
+static int db_scale_src_values[] = {
+    32767, /*   0 db */
+    23197, /* - 3 db */
+    16422, /* - 6 db */
+    11626, /* - 9 db */
+    8231,  /* -12 db */
+    4125,  /* -18 db */
+    2067,  /* -24 db */
+    1036,  /* -30 db */
+    328,   /* -40 db */
+    104,   /* -50 db */
+    33,    /* -60 db */
+};
+#else
+static int db_scale_src_values[] = {
+    32752, /*   0 db */
+    22784, /* - 3 db */
+    14256, /* - 6 db */
+    11752, /* - 9 db */
+    9256,  /* -12 db */
+    4256,  /* -18 db */
+    2186,  /* -24 db */
+    1186,  /* -30 db */
+    373,   /* -40 db */
+    102,   /* -50 db */
+    33,    /* -60 db */
+};
+#endif
+
+int db_scale_count = sizeof db_scale_src_values / sizeof (int);
+
+/* if db_scale_valid is false the content of 
+   db_scale_lcd_coord needs recalculation */
+static bool db_scale_valid = false;
+
+/* contains the lcd x coordinates of the magical
+   scale values in db_scale_src_values */
+static int db_scale_lcd_coord[sizeof db_scale_src_values / sizeof (int)];
+
+
+/**
+ * Calculates dB Value for the peak meter, uses peak value as input
+ * @param int sample - The input value 
+ *                    Make sure that 0 <= value < SAMPLE_RANGE
+ *
+ * @return int - The 2 digit fixed comma result of the euation
+ *               20 * log (sample / SAMPLE_RANGE) + 90
+ *               Output range is 0-8961 (that is 0,0 - 89,6 dB).
+ *               Normally 0dB is full scale, here it is shifted +90dB.
+ *               The calculation is based on the results of a linear
+ *               approximation tool written specifically for this problem
+ *               by Andreas Zwirtes (radhard@gmx.de). The result hat an
+ *               accurracy of better than 2%. It is highly runtime optimized,
+ *               the cascading if-clauses do an successive approximation on
+ *               the input value. This avoids big lookup-tables and
+ *               for-loops.
+ */
+
+int calc_db (int isample) {
+    /* return n+m*(isample-istart)/100 */
+    int n;
+    long m;
+    int istart;
+
+    /* Range 1-4 */
+    if (isample < 119) {
+
+        /* Range 1-2 */
+        if (isample < 5) {
+
+            /* Range 1 */
+            if (isample < 1) {
+                istart = 0;
+                n = 0;
+                m = 5900;
+            }
+
+            /* Range 2 */
+            else {
+                istart = 1;
+                n = 59;
+                m = 34950;
+            }
+        }
+
+        /* Range 3-4 */
+        else {
+
+            /* Range 3 */
+            if (isample < 24) {
+                istart = 5;
+                n = 1457;
+                m = 7168;
+            }
+
+            /* Range 4 */
+            else {
+                istart = 24;
+                n = 2819;
+                m = 1464;
+            }
+        }
+    }
+
+    /* Range 5-8 */
+    else {
+
+        /* Range 5-6 */
+        if (isample < 2918) {
+
+            /* Range 5 */
+            if (isample < 592) {
+                istart = 119;
+                n = 4210;
+                m = 295;
+            }
+
+            /* Range 6 */
+            else {
+                istart = 592;
+                n = 5605;
+                m = 60;
+            }
+        }
+
+        /* Range 7-8 */
+        else {
+
+            /* Range 7 */
+            if (isample < 15352) {
+                istart = 2918;
+                n = 7001;
+                m = 12;
+            }
+
+            /* Range 8 */
+            else {
+                istart = 15352;
+                n = 8439;
+                m = 3;
+            }
+        }
+    }
+   
+    return n + (m * (long)(isample - istart)) / 100L;
+}
+
+
+/**
+ * A helper function for db_to_sample. Don't call it separately but
+ * use db_to_sample. If one or both of min and max are outside the 
+ * range 0 <= min (or max) < 8961 the behaviour of this function is
+ * undefined. It may not return.
+ * @param int min - The minimum of the value range that is searched.
+ * @param int max - The maximum of the value range that is searched.
+ * @param int db  - The value in dBfs * (-100) for which the according
+ *                  minimal peak sample is searched.
+ * @return int - A linear volume value with 0 <= value < MAX_PEAK
+ */
+static int db_to_sample_bin_search(int min, int max, int db){
+    int test = min + (max - min) / 2;
+
+    if (min < max) {
+        if (calc_db(test) < db) {
+            test = db_to_sample_bin_search(test, max, db);
+        } else {
+            if (calc_db(test-1) > db) {
+                test = db_to_sample_bin_search(min, test, db);
+            }
+        }
+    }
+    return test;
+}
+
+/**
+ * Converts a value representing dBfs to a linear
+ * scaled volume info as it is used by the MAS.
+ * An incredibly inefficiant function which is
+ * the vague inverse of calc_db. This really 
+ * should be replaced by something better soon.
+ * 
+ * @param int db - A dBfs * 100 value with 
+ *                 -9000 < value <= 0
+ * @return int - The return value is in the range of
+ *               0 <= return value < MAX_PEAK
+ */
+static int db_to_sample(int db) {
+    int retval = 0;
+
+    /* what is the maximum pseudo db value */
+    int max_peak_db = calc_db(MAX_PEAK - 1);
+
+    /* range check: db value to big */
+    if (max_peak_db + db < 0) {
+        retval = 0;
+    } 
+    
+    /* range check: db value too small */
+    else if (max_peak_db + db >= max_peak_db) {
+        retval = MAX_PEAK -1;
+    } 
+    
+    /* value in range: find the matching linear value */
+    else {
+        retval = db_to_sample_bin_search(0, MAX_PEAK, max_peak_db + db);
+
+        /* as this is a dirty function anyway, we want to adjust the 
+           full scale hit manually to avoid users complaining that when
+           they adjust maximum for 0 dBfs and display it in percent it 
+           shows 99%. That is due to precision loss and this is the 
+           optical fix */
+    }
+
+    return retval;
+}
+
+/**
+ * Set the min value for restriction of the value range.
+ * @param int newmin - depending wether dBfs is used
+ * newmin is a value in dBfs * 100 or in linear percent values.
+ * for dBfs: -9000 < newmin <= 0
+ * for linear: 0 <= newmin <= 100
+ */
+void peak_meter_set_min(int newmin) {
+    if (peak_meter_use_dbfs) {
+        peak_meter_range_min = db_to_sample(newmin);
+
+    } else {
+        if (newmin < peak_meter_range_max) {
+            peak_meter_range_min = newmin * MAX_PEAK / 100;
+        }
+    }
+    db_scale_valid = false;
+}
+
+/**
+ * Returns the minimum value of the range the meter 
+ * displays. If the scale is set to dBfs it returns
+ * dBfs values * 100 or linear percent values.
+ * @return: using dBfs : -9000 < value <= 0
+ *          using linear scale: 0 <= value <= 100
+ */
+int peak_meter_get_min(void) {
+    int retval = 0;
+    if (peak_meter_use_dbfs) {
+        retval = calc_db(peak_meter_range_min) - calc_db(MAX_PEAK - 1);
+    } else {
+        retval = peak_meter_range_min * 100 / MAX_PEAK;
+    }
+    return retval;
+}
+
+/**
+ * Set the max value for restriction of the value range.
+ * @param int newmax - depending wether dBfs is used
+ * newmax is a value in dBfs * 100 or in linear percent values.
+ * for dBfs: -9000 < newmax <= 0
+ * for linear: 0 <= newmax <= 100
+ */
+void peak_meter_set_max(int newmax) {
+    if (peak_meter_use_dbfs) {
+        peak_meter_range_max = db_to_sample(newmax);
+    } else {
+        if (newmax > peak_meter_range_min) {
+            peak_meter_range_max = newmax * MAX_PEAK / 100;
+        }
+    }
+    db_scale_valid = false;
+}
+
+/**
+ * Returns the minimum value of the range the meter 
+ * displays. If the scale is set to dBfs it returns
+ * dBfs values * 100 or linear percent values
+ * @return: using dBfs : -9000 < value <= 0
+ *          using linear scale: 0 <= value <= 100
+ */
+int peak_meter_get_max(void) {
+    int retval = 0;
+    if (peak_meter_use_dbfs) {
+        retval = calc_db(peak_meter_range_max) - calc_db(MAX_PEAK - 1);
+    } else {
+        retval = peak_meter_range_max * 100 / MAX_PEAK;
+    }
+    return retval;
+}
+
+/**
+ * Returns 1 if the meter currently is
+ * displaying dBfs values, 0 if the meter
+ * displays percent values.
+ * @return int - returns 0 or 1.
+ */
+int peak_meter_get_use_dbfs(void) {
+    return peak_meter_use_dbfs ? 1 : 0;
+}
+
+/**
+ * Specifies wether the values displayed are scaled
+ * as dBfs or as linear percent values.
+ * @param int - Set to 0 for linear percent scale. Any other value
+ *              switches on dBfs.
+ */
+void peak_meter_set_use_dbfs(int use){
+    peak_meter_use_dbfs = ((use & 1) == 1);
+    db_scale_valid = false;
+}
+
+/**
+ * Initialize the range of the meter. Only values
+ * that are in the range of [range_min ... range_max]
+ * are displayed.
+ * @param bool dbfs - set to true for dBfs, 
+ *                    set to false for linear scaling in percent 
+ * @param int range_min - Specifies the lower value of the range. 
+ *                        Pass a value dBfs * 100 when dbfs is set to true.
+ *                        Pass a percent value when dbfs is set to false.
+ * @param int range_max - Specifies the upper value of the range. 
+ *                        Pass a value dBfs * 100 when dbfs is set to true.
+ *                        Pass a percent value when dbfs is set to false.
+ */
+void peak_meter_init_range( bool dbfs, int range_min, int range_max) {
+    peak_meter_use_dbfs = dbfs;
+    peak_meter_set_min(range_min);
+    peak_meter_set_max(range_max);
+}
+
+/**
+ * Initialize the peak meter with all relevant values concerning times.
+ * @param int release - Set the maximum amount of pixels the meter is allowed
+ *                      to decrease with each redraw
+ * @param int hold - Select the time preset for the time the peak indicator 
+ *                   is reset after a peak occurred. The preset values are 
+ *                   stored in max_time_out.
+ * @param int clip_hold - Select the time preset for the time the peak 
+ *                        indicator is reset after a peak occurred. The preset 
+ *                        values are stored in clip_time_out.
+ */
+void peak_meter_init_times(int release, int hold, int clip_hold) {
+    peak_meter_hold = hold;
+    peak_meter_release = release;
+    peak_meter_clip_hold = clip_hold;
+}
+
 /**
  * Set the source of the peak meter to playback or to 
  * record.
@@ -127,20 +502,58 @@ void peak_meter_peek(void) {
         (left  == MAX_PEAK - 1)) {
         peak_meter_l_clip = true;
         peak_meter_clip_timeout_l = 
-            current_tick + clip_time_out[global_settings.peak_meter_clip_hold];
+            current_tick + clip_time_out[peak_meter_clip_hold];
     }
 
     if ((right == peak_meter_r) && 
         (right == MAX_PEAK - 1)) {
         peak_meter_r_clip = true;
         peak_meter_clip_timeout_r = 
-            current_tick + clip_time_out[global_settings.peak_meter_clip_hold];
+            current_tick + clip_time_out[peak_meter_clip_hold];
     }
 
-    /* peaks are searched -> we have to find the maximum */
+    /* peaks are searched -> we have to find the maximum. When
+       many calls of peak_meter_peek the maximum value will be
+       stored in peak_meter_x. This maximum is reset by the
+       functions peak_meter_read_x. */
     peak_meter_l = MAX(peak_meter_l, left);
     peak_meter_r = MAX(peak_meter_r, right);
+
+#ifdef PM_DEBUG
+    peek_calls++;
+#endif
+}
+
+
+/**
+ * The thread function for the peak meter calls peak_meter_peek 
+ * to reas out the mas and find maxima, clips, etc. No display
+ * is performed.
+ */
+/*
+void peak_meter_thread(void) {
+    sleep(5000);
+    while (1) {
+        if (peak_meter_enabled && peak_meter_use_thread){
+            peak_meter_peek();
+        }
+        yield();
+    }
+}
+*/
+
+/**
+ * Creates the peak meter thread 
+ */
+/*
+void peak_meter_init(void) {
+    create_thread(
+        peak_meter_thread, 
+        peak_meter_stack, 
+        sizeof peak_meter_stack, 
+        "peakmeter");
 }
+*/
 
 /**
  * Reads out the peak volume of the left channel.
@@ -149,10 +562,20 @@ void peak_meter_peek(void) {
  * is in the range 0 <= value < MAX_PEAK.
  */
 static int peak_meter_read_l (void) {
+    /* peak_meter_l contains the maximum of
+       all peak values that were read by peak_meter_peek 
+       since the last call of peak_meter_read_r */
     int retval = peak_meter_l;
+#ifdef PM_DEBUG
+    peek_calls = 0;
+#endif
+
 #ifdef SIMULATOR
     peak_meter_l = 8000;
 #else
+    /* reset peak_meter_l so that subsequent calls of
+       peak_meter_peek doesn't get fooled by an old
+       maximum value */
     peak_meter_l = mas_codec_readreg(peak_meter_src_l);
 #endif
     return retval;
@@ -165,10 +588,20 @@ static int peak_meter_read_l (void) {
  * is in the range 0 <= value < MAX_PEAK.
  */
 static int peak_meter_read_r (void) {
+    /* peak_meter_r contains the maximum of
+       all peak values that were read by peak_meter_peek 
+       since the last call of peak_meter_read_r */
     int retval = peak_meter_r;
+#ifdef PM_DEBUG
+    peek_calls = 0;
+#endif
+
 #ifdef SIMULATOR
     peak_meter_l = 8000;
 #else
+    /* reset peak_meter_r so that subsequent calls of
+       peak_meter_peek doesn't get fooled by an old
+       maximum value */
     peak_meter_r = mas_codec_readreg(peak_meter_src_r);
 #endif
     return retval;
@@ -190,6 +623,51 @@ void peak_meter_set_clip_hold(int time) {
     }
 }
 
+/**
+ * Scales a peak value as read from the MAS to the range of meterwidth.
+ * The scaling is performed according to the scaling method (dBfs / linear)
+ * and the range (peak_meter_range_min .. peak_meter_range_max).
+ * @param unsigned short val - The volume value. Range: 0 <= val < MAX_PEAK
+ * @param int meterwidht - The widht of the meter in pixel
+ * @return unsigned short - A value 0 <= return value <= meterwidth
+ */
+unsigned short peak_meter_scale_value(unsigned short val, int meterwidth){
+    int range;
+    int retval;
+
+    if (val <= peak_meter_range_min) {
+        return 0;
+    }
+
+    if (val >= peak_meter_range_max) {
+        return meterwidth;
+    }
+
+    retval = val;
+
+    /* different scaling is used for dBfs and linear percent */
+    if (peak_meter_use_dbfs) {
+
+        /* needed the offset in 'zoomed' meters */
+        int dbmin = calc_db(peak_meter_range_min);
+
+        range = calc_db(peak_meter_range_max) - dbmin;
+
+        /* scale the samples dBfs */
+        retval  = (calc_db(retval) - dbmin) * meterwidth / range;
+    }
+
+    /* Scale for linear percent display */
+    else
+    {
+        range =(peak_meter_range_max - peak_meter_range_min);
+
+        /* scale the samples */
+        retval  = ((retval - peak_meter_range_min) * meterwidth) / range;
+    }
+    return retval;
+}
+
 
 /**
  * Draws a peak meter in the specified size at the specified position.
@@ -208,22 +686,66 @@ void peak_meter_draw(int x, int y, int width, int height) {
     int meterwidth = width - 3;
     int i;
 
+#ifdef PM_DEBUG
+    static long pm_tick = 0;
+    int tmp = peek_calls;
+#endif
+
     /* if disabled only draw the peak meter */
     if (peak_meter_enabled) {
+
         /* read the volume info from MAS */
         left  = peak_meter_read_l(); 
         right = peak_meter_read_r(); 
-
         peak_meter_peek();
 
+        /* restrict the range to avoid drawing outside the lcd */
+        left = MAX(peak_meter_range_min, left);
+        left = MIN(peak_meter_range_max, left);
+
+        right = MAX(peak_meter_range_min, right);
+        right = MIN(peak_meter_range_max, right);
+
+        /* scale the samples dBfs */
+        left  = peak_meter_scale_value(left, meterwidth);
+        right = peak_meter_scale_value(right, meterwidth);
+    
+        /* if the scale has changed -> recalculate the scale 
+           (The scale becomes invalid when the range changed.) */
+        if (!db_scale_valid){
+
+            if (peak_meter_use_dbfs) {
+                db_scale_count = sizeof db_scale_src_values / sizeof (int);
+                for (i = 0; i < db_scale_count; i++){
+                    /* find the real x-coords for predefined interesting
+                       dBfs values. These only are recalculated when the
+                       scaling of the meter changed. */
+                        db_scale_lcd_coord[i] = 
+                            peak_meter_scale_value(
+                                db_scale_src_values[i], 
+                                meterwidth - 1);
+                } 
+            }
 
-        /* scale the samples */
-        left  /= (MAX_PEAK / meterwidth);
-        right /= (MAX_PEAK / meterwidth);
+            /* when scaling linear we simly make 10% steps */
+            else {
+                int range = peak_meter_range_max - peak_meter_range_min;
+                db_scale_count = 10;
+                for (i = 0; i < db_scale_count; i++) {
+                    db_scale_lcd_coord[i] = 
+                        (i * (MAX_PEAK / 10) - peak_meter_range_min) *
+                        meterwidth / range;
+                }
+            }
+
+            /* mark scale valid to avoid recalculating dBfs values
+               of the scale. */
+            db_scale_valid = true;
+        }
 
         /* apply release */
-        left  = MAX(left , last_left  - global_settings.peak_meter_release);
-        right = MAX(right, last_right - global_settings.peak_meter_release);
+        left  = MAX(left , last_left  - peak_meter_release);
+        right = MAX(right, last_right - peak_meter_release);
 
         /* reset max values after timeout */
         if (TIME_AFTER(current_tick, peak_meter_timeout_l)){
@@ -250,13 +772,13 @@ void peak_meter_draw(int x, int y, int width, int height) {
         if (left > peak_meter_max_l) {
             peak_meter_max_l = left - 1;
             peak_meter_timeout_l = 
-                current_tick + max_time_out[global_settings.peak_meter_hold];
+                current_tick + max_time_out[peak_meter_hold];
         }
 
         if (right > peak_meter_max_r) {
             peak_meter_max_r = right - 1;
             peak_meter_timeout_r = 
-                current_tick + max_time_out[global_settings.peak_meter_hold];
+                current_tick + max_time_out[peak_meter_hold];
         }
     }
 
@@ -283,13 +805,90 @@ void peak_meter_draw(int x, int y, int width, int height) {
         lcd_fillrect(x + meterwidth, y + height / 2, 3, height / 2 - 1);
     }
 
-    /* draw scale */
+    /* draw scale end */
     lcd_drawline(x + meterwidth, y,
                  x + meterwidth, y + height - 2);
-    for (i = 0; i < 10; i++) {
-        lcd_invertpixel(x + meterwidth * i / 10, y + height / 2 - 1);
+    
+    /* draw dots for scale marks */
+    for (i = 0; i < db_scale_count; i++) {
+        /* The x-coordinates of interesting scale mark points 
+           have been calculated before */
+        lcd_invertpixel(db_scale_lcd_coord[i], y + height / 2 - 1);
+    }
+
+#ifdef PM_DEBUG
+    /* display a bar to show how many calls to peak_meter_peek 
+       have ocurred since the last display */
+    lcd_invertrect(x, y, tmp, 3);
+
+    if (tmp < PEEKS_PER_DRAW_SIZE) {
+        peeks_per_redraw[tmp]++;
+    }
+
+    tmp = current_tick - pm_tick;
+    if (tmp < TICKS_PER_DRAW_SIZE ){
+        ticks_per_redraw[tmp] ++;
     }
 
+    /* display a bar to show how many ticks have passed since 
+       the last redraw */
+    lcd_invertrect(x, y + height / 2, current_tick - pm_tick, 2);
+    pm_tick = current_tick;
+#endif
+
     last_left = left;
     last_right = right;
 }
+
+#ifdef PM_DEBUG
+static void peak_meter_clear_histogram(void) {
+    int i = 0;
+    for (i = 0; i < TICKS_PER_DRAW_SIZE; i++) {
+        ticks_per_redraw[i] = (unsigned int)0;
+    }
+
+    for (i = 0; i < PEEKS_PER_DRAW_SIZE; i++) {
+        peeks_per_redraw[i] = (unsigned int)0;
+    }
+}
+
+bool peak_meter_histogram(void) {
+    int i;
+    int btn = BUTTON_NONE;
+    while ((btn & BUTTON_OFF) != BUTTON_OFF )
+    {
+        unsigned int max = 0;
+        int y = 0;
+        int x = 0;
+        lcd_clear_display();
+
+        for (i = 0; i < PEEKS_PER_DRAW_SIZE; i++) {
+            max = MAX(max, peeks_per_redraw[i]);
+        }
+
+        for (i = 0; i < PEEKS_PER_DRAW_SIZE; i++) {
+            x = peeks_per_redraw[i] * (LCD_WIDTH - 1)/ max;
+            lcd_drawline(0, y + i, x, y + i);
+        }
+
+        y = PEEKS_PER_DRAW_SIZE + 1;
+        max = 0;
+
+        for (i = 0; i < TICKS_PER_DRAW_SIZE; i++) {
+            max = MAX(max, ticks_per_redraw[i]);
+        }
+
+        for (i = 0; i < TICKS_PER_DRAW_SIZE; i++) {
+            x = ticks_per_redraw[i] * (LCD_WIDTH - 1)/ max;
+            lcd_drawline(0, y + i, x, y + i);
+        }
+        lcd_update();
+        
+        btn = button_get(true);
+        if (btn == BUTTON_PLAY) {
+            peak_meter_clear_histogram();
+        }
+    }
+    return false;
+}
+#endif 
diff --git a/apps/recorder/peakmeter.h b/apps/recorder/peakmeter.h
index a5f25808e6..356926f9de 100644
--- a/apps/recorder/peakmeter.h
+++ b/apps/recorder/peakmeter.h
@@ -19,12 +19,32 @@
 #ifndef __PEAKMETER_H__
 #define __PEAKMETER_H__
 
+/*#define PM_DEBUG */
+#ifdef PM_DEBUG 
+extern bool peak_meter_histogramm(void);
+#endif
+
+
 extern bool peak_meter_enabled;
+extern int  peak_meter_fps;
 
-extern void peak_meter_init(void);
 extern void peak_meter_playback(bool playback);
 extern void peak_meter_draw(int x, int y, int width, int height);
 extern void peak_meter_set_clip_hold(int time);
 extern void peak_meter_peek(void);
+extern void peak_meter_init_range( bool dbfs, int range_min, int range_max);
+extern void peak_meter_init_times(int release, int hold, int clip_hold);
+
+extern void peak_meter_set_min(int newmin);
+extern int  peak_meter_get_min(void);
+extern void peak_meter_set_max(int newmax);
+extern int  peak_meter_get_max(void);
+extern void peak_meter_set_use_dbfs(int use);
+extern int  peak_meter_get_use_dbfs(void);
+extern int  calc_db (int isample);
+extern unsigned short peak_meter_scale_value(unsigned short val, int meterwidth);
+
+extern unsigned short peak_meter_range_min;
+extern unsigned short peak_meter_range_max;
 
 #endif /* __PEAKMETER_H__ */
diff --git a/apps/settings.c b/apps/settings.c
index cee7a286f6..c17f42fd52 100644
--- a/apps/settings.c
+++ b/apps/settings.c
@@ -44,6 +44,7 @@
 #ifdef HAVE_LCD_BITMAP
 #include "icons.h"
 #include "font.h"
+#include "peakmeter.h"
 #endif
 #include "lang.h"
 #include "language.h"
@@ -52,7 +53,7 @@
 struct user_settings global_settings;
 char rockboxdir[] = ROCKBOX_DIR;       /* config/font/data file directory */
 
-#define CONFIG_BLOCK_VERSION 2
+#define CONFIG_BLOCK_VERSION 3
 #define CONFIG_BLOCK_SIZE 512
 #define RTC_BLOCK_SIZE 44
 
@@ -89,10 +90,14 @@ offset  abs
 0x16    0x2a    <(int) Byte offset into resume file>
 0x1a    0x2e    <time until disk spindown>
 0x1b    0x2f    <browse current, play selected>
-0x1c    0x30    <peak meter hold timeout (bit 0-4)>
-0x1d    0x31    <peak meter clip hold timeout (bit 0-4)>
-0x1e    0x32    <peak meter release step size>
-0x1f    0x33    <repeat mode>
+0x1c    0x30    <peak meter hold timeout (bit 0-4)>, 
+                 peak_meter_performance (bit 7)
+0x1d    0x31    <peak meter clip hold timeout (bit 0-4)
+0x1e    0x32    <peak meter release step size, 
+                 peak_meter_dbfs (bit 7)
+0x1f    0x33    <peak meter min either in -db or in percent>
+0x20    0x34    <peak meter max either in -db or in percent>
+0x21    0x35    <repeat mode>
 
         <all unused space filled with 0xff>
 
@@ -316,9 +321,13 @@ int settings_save( void )
          ((global_settings.play_selected & 1) << 1));
     
     config_block[0x1c] = (unsigned char)global_settings.peak_meter_hold;
-    config_block[0x1d] = (unsigned char)global_settings.peak_meter_clip_hold;
-    config_block[0x1e] = (unsigned char)global_settings.peak_meter_release;
-    config_block[0x1f] = (unsigned char)global_settings.repeat_mode;
+    config_block[0x1d] = (unsigned char)global_settings.peak_meter_clip_hold |
+        (global_settings.peak_meter_performance ? 0x80 : 0);
+    config_block[0x1e] = global_settings.peak_meter_release |
+        (global_settings.peak_meter_dbfs ? 0x80 : 0);
+    config_block[0x1f] = (unsigned char)global_settings.peak_meter_min;
+    config_block[0x20] = (unsigned char)global_settings.peak_meter_max;
+    config_block[0x21] = (unsigned char)global_settings.repeat_mode;
 
     memcpy(&config_block[0x24], &global_settings.total_uptime, 4);
 
@@ -355,6 +364,35 @@ int settings_save( void )
     return 0;
 }
 
+#ifdef HAVE_LCD_BITMAP
+/**
+ * Applies the range infos stored in global_settings to 
+ * the peak meter. 
+ */
+void settings_apply_pm_range(void)
+{
+    int pm_min, pm_max;
+
+    /* depending on the scale mode (dBfs or percent) the values
+       of global_settings.peak_meter_dbfs have different meanings */
+    if (global_settings.peak_meter_dbfs) 
+    {
+        /* convert to dBfs * 100          */
+        pm_min = -(((int)global_settings.peak_meter_min) * 100);
+        pm_max = -(((int)global_settings.peak_meter_max) * 100);
+    }
+    else 
+    {
+        /* percent is stored directly -> no conversion */
+        pm_min = global_settings.peak_meter_min;
+        pm_max = global_settings.peak_meter_max;
+    }
+
+    /* apply the range */
+    peak_meter_init_range(global_settings.peak_meter_dbfs, pm_min, pm_max);
+}
+#endif /* HAVE_LCD_BITMAP */
+
 void settings_apply(void)
 {
     char buf[64];
@@ -381,6 +419,13 @@ void settings_apply(void)
         CHARGE_RESTART_LO : CHARGE_RESTART_HI;
 #endif
 
+#ifdef HAVE_LCD_BITMAP
+    settings_apply_pm_range();
+    peak_meter_init_times(
+        global_settings.peak_meter_release, global_settings.peak_meter_hold, 
+        global_settings.peak_meter_clip_hold);
+#endif
+
     if ( global_settings.wps_file[0] && 
          global_settings.wps_file[0] != 0xff ) {
         snprintf(buf, sizeof buf, ROCKBOX_DIR "/%s.wps",
@@ -500,14 +545,25 @@ void settings_load(void)
         if (config_block[0x1c] != 0xFF)
             global_settings.peak_meter_hold = (config_block[0x1c]) & 0x1f;
 
-        if (config_block[0x1d] != 0xFF)
+        if (config_block[0x1d] != 0xFF) {
             global_settings.peak_meter_clip_hold = (config_block[0x1d]) & 0x1f;
+            global_settings.peak_meter_performance = 
+                (config_block[0x1d] & 0x80) != 0;
+        }
 
-        if (config_block[0x1e] != 0xFF)
-            global_settings.peak_meter_release = config_block[0x1e];
+        if (config_block[0x1e] != 0xFF) {
+            global_settings.peak_meter_release = config_block[0x1e] & 0x7f;
+            global_settings.peak_meter_dbfs = (config_block[0x1e] & 0x80) != 0;
+        }
 
         if (config_block[0x1f] != 0xFF)
-            global_settings.repeat_mode = config_block[0x1f];
+            global_settings.peak_meter_min = config_block[0x1f];
+
+        if (config_block[0x20] != 0xFF)
+            global_settings.peak_meter_max = config_block[0x20];
+
+        if (config_block[0x21] != 0xFF)
+            global_settings.repeat_mode = config_block[0x21];
 
         if (config_block[0x24] != 0xFF)
             memcpy(&global_settings.total_uptime, &config_block[0x24], 4);
@@ -685,8 +741,12 @@ void settings_reset(void) {
     global_settings.browse_current = false;
     global_settings.play_selected = true;
     global_settings.peak_meter_release = 8;
-    global_settings.peak_meter_hold = 1;
+    global_settings.peak_meter_hold = 3;
     global_settings.peak_meter_clip_hold = 16;
+    global_settings.peak_meter_dbfs = true;
+    global_settings.peak_meter_min = 60;
+    global_settings.peak_meter_max = 0;
+    global_settings.peak_meter_performance = false;
     global_settings.wps_file[0] = 0;
     global_settings.font_file[0] = 0;
     global_settings.lang_file[0] = 0;
diff --git a/apps/settings.h b/apps/settings.h
index bc8767d532..655b2e0245 100644
--- a/apps/settings.h
+++ b/apps/settings.h
@@ -100,6 +100,10 @@ struct user_settings
     int peak_meter_release;   /* units per read out */
     int peak_meter_hold;      /* hold time for peak meter in 1/100 s */
     int peak_meter_clip_hold; /* hold time for clips */
+    bool peak_meter_dbfs;     /* show linear or dbfs values */
+    bool peak_meter_performance;  /* true: high performance, else save energy*/
+    unsigned char peak_meter_min; /* range minimum */
+    unsigned char peak_meter_max; /* range maximum */
 
     /* show status bar */
     bool statusbar;    /* 0=hide, 1=show */
@@ -121,6 +125,7 @@ int settings_save(void);
 void settings_load(void);
 void settings_reset(void);
 void settings_apply(void);
+void settings_apply_pm_range(void);
 void settings_display(void);
 
 bool settings_load_config(char* file);
diff --git a/apps/settings_menu.c b/apps/settings_menu.c
index 6f527f5224..ed2f97e390 100644
--- a/apps/settings_menu.c
+++ b/apps/settings_menu.c
@@ -74,27 +74,44 @@ static bool volume_type(void)
                        names, 2, NULL);
 }
 
+#ifdef PM_DEBUG
+static bool peak_meter_fps_menu(void) {
+    bool retval = false;
+    retval = set_int( "Refresh rate", "/s", 
+             &peak_meter_fps,
+             NULL, 1, 5, 40);
+    return retval;
+}
+#endif /* PM_DEBUG */
+
 /**
  * Menu to set the hold time of normal peaks.
  */
-static bool peak_meter_hold(void) 
-{
+static bool peak_meter_hold(void) {
+    bool retval = false;
     char* names[] = { str(LANG_OFF),
                       "200 ms ", "300 ms ", "500 ms ", "1 s ", "2 s ",
                       "3 s ", "4 s ", "5 s ", "6 s ", "7 s",
                       "8 s", "9 s", "10 s", "15 s", "20 s",
                       "30 s", "1 min"
     };
-    return set_option( str(LANG_PM_PEAK_HOLD), 
+    retval = set_option( str(LANG_PM_PEAK_HOLD), 
                        &global_settings.peak_meter_hold, names,
                        18, NULL);
+
+    peak_meter_init_times(global_settings.peak_meter_release,
+        global_settings.peak_meter_hold, 
+        global_settings.peak_meter_clip_hold);
+
+    return retval;
 }
 
 /**
  * Menu to set the hold time of clips.
  */
-static bool peak_meter_clip_hold(void) 
-{
+static bool peak_meter_clip_hold(void) {
+    bool retval = false;
+
     char* names[] = { str(LANG_PM_ETERNAL),
                       "1s ", "2s ", "3s ", "4s ", "5s ",
                       "6s ", "7s ", "8s ", "9s ", "10s",
@@ -103,19 +120,167 @@ static bool peak_meter_clip_hold(void)
                       "10min", "20min", "45min", "90min"
     };
 
-    return set_option( str(LANG_PM_CLIP_HOLD), 
+    retval = set_option( str(LANG_PM_CLIP_HOLD), 
                        &global_settings.peak_meter_clip_hold, names,
                        25, peak_meter_set_clip_hold);
+
+    peak_meter_init_times(global_settings.peak_meter_release,
+        global_settings.peak_meter_hold, 
+        global_settings.peak_meter_clip_hold);
+
+    return retval;
 }
 
 /**
  * Menu to set the release time of the peak meter.
  */
-static bool peak_meter_release(void)  
-{
-    return set_int( str(LANG_PM_RELEASE), str(LANG_PM_UNITS_PER_READ), 
+static bool peak_meter_release(void)  {
+    bool retval = false;
+
+    /* The range of peak_meter_release is restricted so that it
+       fits into a 7 bit number. The 8th bit is used for storing
+       something else in the rtc ram.
+       Also, the max value is 0x7e, since the RTC value 0xff is reserved */
+    retval = set_int( str(LANG_PM_RELEASE), str(LANG_PM_UNITS_PER_READ), 
                     &global_settings.peak_meter_release,
-                    NULL, 1, 1, LCD_WIDTH);
+             NULL, 1, 1, 0x7e);
+
+    peak_meter_init_times(global_settings.peak_meter_release,
+        global_settings.peak_meter_hold, 
+        global_settings.peak_meter_clip_hold);
+
+    return retval;
+}
+
+/**
+ * Menu to select wether the scale of the meter 
+ * displays dBfs of linear values.
+ */
+static bool peak_meter_scale(void) {
+    bool retval = false;
+    bool use_dbfs = global_settings.peak_meter_dbfs;
+    retval = set_bool_options(str(LANG_PM_SCALE), 
+        &use_dbfs, 
+        str(LANG_PM_DBFS), str(LANG_PM_LINEAR));
+
+    /* has the user really changed the scale? */
+    if (use_dbfs != global_settings.peak_meter_dbfs) {
+
+        /* store the change */
+        global_settings.peak_meter_dbfs = use_dbfs;
+        peak_meter_set_use_dbfs(use_dbfs);
+
+        /* If the user changed the scale mode the meaning of
+           peak_meter_min (peak_meter_max) has changed. Thus we have
+           to convert the values stored in global_settings. */
+        if (use_dbfs) {
+
+            /* we only store -dBfs */
+            global_settings.peak_meter_min = -peak_meter_get_min() / 100;
+            global_settings.peak_meter_max = -peak_meter_get_max() / 100;
+        } else {
+            int max;
+            
+            /* linear percent */
+            global_settings.peak_meter_min = peak_meter_get_min();
+
+            /* converting dBfs -> percent results in a precision loss.
+               I assume that the user doesn't bother that conversion
+               dBfs <-> percent isn't symmetrical for odd values but that
+               he wants 0 dBfs == 100%. Thus I 'correct' the percent value
+               resulting from dBfs -> percent manually here */
+            max = peak_meter_get_max();
+            global_settings.peak_meter_max = max < 99 ? max : 100;
+        }
+        settings_apply_pm_range();
+    }
+    return retval;
+}
+
+/**
+ * Adjust the min value of the value range that
+ * the peak meter shall visualize.
+ */
+static bool peak_meter_min(void) {
+    bool retval = false;
+    if (global_settings.peak_meter_dbfs) {
+
+        /* for dBfs scale */
+        int range_max = -global_settings.peak_meter_max;
+        int min = -global_settings.peak_meter_min;
+
+        retval =  set_int(str(LANG_PM_MIN), str(LANG_PM_DBFS),
+            &min, NULL, 1, -89, range_max);
+
+        global_settings.peak_meter_min = - min;
+    } 
+
+    /* for linear scale */
+    else {
+        int min = global_settings.peak_meter_min;
+
+        retval =  set_int(str(LANG_PM_MIN), "%",
+            &min, NULL, 
+            1, 0, global_settings.peak_meter_max - 1);
+
+        global_settings.peak_meter_min = (unsigned char)min;
+    }
+
+    settings_apply_pm_range();
+    return retval;
+}
+
+
+/**
+ * Adjust the max value of the value range that
+ * the peak meter shall visualize.
+ */
+static bool peak_meter_max(void) {
+    bool retval = false;
+    if (global_settings.peak_meter_dbfs) {
+
+        /* for dBfs scale */
+        int range_min = -global_settings.peak_meter_min;
+        int max = -global_settings.peak_meter_max;;
+
+        retval =  set_int(str(LANG_PM_MAX), str(LANG_PM_DBFS),
+            &max, NULL, 1, range_min, 0);
+
+        global_settings.peak_meter_max = - max;
+
+    } 
+    
+    /* for linear scale */
+    else {
+        int max = global_settings.peak_meter_max;
+
+        retval =  set_int(str(LANG_PM_MAX), "%",
+            &max, NULL, 
+            1, global_settings.peak_meter_min + 1, 100);
+
+        global_settings.peak_meter_max = (unsigned char)max;
+    }
+
+    settings_apply_pm_range();
+    return retval;
+}
+
+/**
+ * Menu to select wether the meter is in
+ * precision or in energy saver mode
+ */
+static bool peak_meter_performance(void) {
+    bool retval = false;
+    retval = set_bool_options(str(LANG_PM_PERFORMANCE), 
+        &global_settings.peak_meter_performance, 
+        str(LANG_PM_HIGH_PERFORMANCE), str(LANG_PM_ENERGY_SAVER));
+
+    if (global_settings.peak_meter_performance) {
+        peak_meter_fps = 25;
+    } else {
+        peak_meter_fps = 20;
+    }
+    return retval;
 }
 
 /**
@@ -130,6 +295,13 @@ static bool peak_meter_menu(void)
         { str(LANG_PM_RELEASE)  , peak_meter_release   },  
         { str(LANG_PM_PEAK_HOLD), peak_meter_hold      },  
         { str(LANG_PM_CLIP_HOLD), peak_meter_clip_hold },
+        { str(LANG_PM_PERFORMANCE), peak_meter_performance },
+#ifdef PM_DEBUG
+        { "Refresh rate"        , peak_meter_fps_menu  },
+#endif
+        { str(LANG_PM_SCALE)    , peak_meter_scale     },
+        { str(LANG_PM_MIN)      , peak_meter_min       },
+        { str(LANG_PM_MAX)      , peak_meter_max       },
     };
     
     m=menu_init( items, sizeof items / sizeof(struct menu_items) );
@@ -137,7 +309,7 @@ static bool peak_meter_menu(void)
     menu_exit(m);
     return result;
 }
-#endif
+#endif /* HAVE_LCD_BITMAP */
 
 static bool shuffle(void)
 {
diff --git a/apps/wps-display.c b/apps/wps-display.c
index 6bca8cb40d..b70c1359d1 100644
--- a/apps/wps-display.c
+++ b/apps/wps-display.c
@@ -55,17 +55,10 @@
 #endif
 
 #define FORMAT_BUFFER_SIZE 300
-struct format_flags
-{
-    bool dynamic;
-    bool scroll;
-    bool player_progress;
-    bool peak_meter;
-};
 
 static char format_buffer[FORMAT_BUFFER_SIZE];
 static char* format_lines[MAX_LINES];
-static bool dynamic_lines[MAX_LINES];
+static unsigned char line_type[MAX_LINES];
 static int ff_rewind_count;
 bool wps_time_countup = true;
 static bool wps_loaded = false;
@@ -218,9 +211,7 @@ static char* get_dir(char* buf, int buf_size, char* path, int level)
  * buf      - buffer to certain tags, such as track number, play time or 
  *           directory name.
  * buf_size - size of buffer.
- * flags    - flags in this struct will be set depending on the tag:
- *            dynamic - if the tag data changes over time (like play time);
- *            player_progress - set if the tag is %pb.
+ * flags    - returns the type of the line. See constants i wps-display.h
  *
  * Returns the tag. NULL indicates the tag wasn't available.
  */
@@ -228,7 +219,7 @@ static char* get_tag(struct mp3entry* id3,
                      char* tag, 
                      char* buf, 
                      int buf_size,
-                     struct format_flags* flags)
+                     unsigned char* flags)
 {
     if ((0 == tag[0]) || (0 == tag[1]))
     {
@@ -238,6 +229,7 @@ static char* get_tag(struct mp3entry* id3,
     switch (tag[0])
     {
         case 'i':  /* ID3 Information */
+            *flags |= WPS_REFRESH_STATIC;
             switch (tag[1])
             {
                 case 't':  /* ID3 Title */
@@ -263,6 +255,7 @@ static char* get_tag(struct mp3entry* id3,
             break;
 
         case 'f':  /* File Information */
+            *flags |= WPS_REFRESH_STATIC;
             switch(tag[1])
             {
                 case 'v':  /* VBR file? */
@@ -310,40 +303,42 @@ static char* get_tag(struct mp3entry* id3,
             switch(tag[1])
             {
                 case 'b':  /* progress bar */
-                    flags->player_progress = true;
-                    flags->dynamic = true;
+                    *flags |= WPS_REFRESH_PLAYER_PROGRESS;
                     return "\x01";
 
                 case 'p':  /* Playlist Position */
+                    *flags |= WPS_REFRESH_STATIC;
                     snprintf(buf, buf_size, "%d", id3->index + 1);
                     return buf;
 
                 case 'n':  /* Playlist Name (without path) */
+                    *flags |= WPS_REFRESH_STATIC;
                     return playlist_name(buf, buf_size);
 
                 case 'e':  /* Playlist Total Entries */
+                    *flags |= WPS_REFRESH_STATIC;
                     snprintf(buf, buf_size, "%d", playlist_amount());
                     return buf;
 
                 case 'c':  /* Current Time in Song */
-                    flags->dynamic = true;
+                    *flags |= WPS_REFRESH_DYNAMIC;
                     format_time(buf, buf_size, id3->elapsed + ff_rewind_count);
                     return buf;
 
                 case 'r': /* Remaining Time in Song */
-                    flags->dynamic = true;
+                    *flags |= WPS_REFRESH_DYNAMIC;
                     format_time(buf, buf_size, 
                                 id3->length - id3->elapsed - ff_rewind_count);
                     return buf;
 
                 case 't':  /* Total Time */
+                    *flags |= WPS_REFRESH_STATIC;
                     format_time(buf, buf_size, id3->length);
                     return buf;
 
 #ifdef HAVE_LCD_BITMAP
                 case 'm': /* Peak Meter */
-                    flags->peak_meter = true;
-                    flags->dynamic = true;
+                    *flags |= WPS_REFRESH_PEAK_METER;
                     return "\x01";
 #endif
             }
@@ -351,6 +346,7 @@ static char* get_tag(struct mp3entry* id3,
     
         case 'd': /* Directory path information */
             {
+                *flags |= WPS_REFRESH_STATIC;
                 int level = tag[1] - '0';
                 /* d1 through d9 */
                 if ((0 < level) && (9 > level))
@@ -437,16 +433,13 @@ static char* skip_conditional(char* fmt, bool to_else)
  * buf_size - the size of buffer.
  * id3      - the ID3 data to format with.
  * fmt      - format description.
- * flags    - flags in this struct will be set depending on the tag:
- *            dynamic - if the tag data changes over time (like play time);
- *            player_progress - set if the tag is %pb.
- *            scroll - if line scrolling is requested.
+ * flags    - returns the type of the line. See constants i wps-display.h
  */
 static void format_display(char* buf, 
                            int buf_size, 
                            struct mp3entry* id3, 
                            char* fmt, 
-                           struct format_flags* flags)
+                           unsigned char* flags)
 {
     char temp_buf[128];
     char* buf_end = buf + buf_size - 1;   /* Leave room for end null */
@@ -483,7 +476,7 @@ static void format_display(char* buf,
                 break;
         
             case 's':
-                flags->scroll = true;
+                *flags |= WPS_REFRESH_SCROLL;
                 ++fmt;
                 break;
         
@@ -526,10 +519,10 @@ static void format_display(char* buf,
     *buf = 0;
 }
 
-bool wps_refresh(struct mp3entry* id3, int ffwd_offset, bool refresh_all)
+bool wps_refresh(struct mp3entry* id3, int ffwd_offset, unsigned char refresh_mode)
 {
     char buf[MAX_PATH];
-    struct format_flags flags;
+    unsigned char flags;
     int i;
 #ifdef HAVE_LCD_BITMAP
     /* to find out wether the peak meter is enabled we
@@ -554,16 +547,15 @@ bool wps_refresh(struct mp3entry* id3, int ffwd_offset, bool refresh_all)
         if ( !format_lines[i] )
             break;
 
-        if (dynamic_lines[i] || refresh_all)
+        if ((line_type[i] & refresh_mode) || 
+            (refresh_mode == WPS_REFRESH_ALL))
         {
-            flags.dynamic = false;
-            flags.scroll = false;
-            flags.player_progress = false;
-            flags.peak_meter = false;
+            flags = 0;
             format_display(buf, sizeof(buf), id3, format_lines[i], &flags);
-            dynamic_lines[i] = flags.dynamic;
+            line_type[i] = flags;
             
-            if (flags.player_progress) {
+            /* progress */
+            if (flags & refresh_mode & WPS_REFRESH_PLAYER_PROGRESS) {
 #ifdef HAVE_LCD_CHARCELLS
                 draw_player_progress(id3, ff_rewind_count);
 #else
@@ -578,11 +570,12 @@ bool wps_refresh(struct mp3entry* id3, int ffwd_offset, bool refresh_all)
             }
 
 #ifdef HAVE_LCD_BITMAP
-            if (flags.peak_meter) {
+            /* peak meter */
+            if (flags & refresh_mode & WPS_REFRESH_PEAK_METER) {
                 int peak_meter_y;
-                int w,h;
+                struct font *fnt = font_get(FONT_UI);
+                int h = fnt->height;
                 int offset = global_settings.statusbar ? STATUSBAR_HEIGHT : 0;
-                lcd_getstringsize("M",&w,&h);
 
                 peak_meter_y = i * h + offset;
 
@@ -601,10 +594,13 @@ bool wps_refresh(struct mp3entry* id3, int ffwd_offset, bool refresh_all)
             }
 #endif
 
-            if (flags.scroll && !flags.dynamic)
+            /* static line */
+            if (flags & WPS_REFRESH_SCROLL)
             {
+                if (refresh_mode & WPS_REFRESH_SCROLL) {
                 lcd_puts_scroll(0, i, buf);
             }
+            }
             else
             {
                 lcd_puts(0, i, buf);
@@ -656,7 +652,7 @@ bool wps_display(struct mp3entry* id3)
             }
         }
     }
-    wps_refresh(id3, 0, true);
+    wps_refresh(id3, 0, WPS_REFRESH_ALL);
     status_draw();
     lcd_update();
     return false;
diff --git a/apps/wps-display.h b/apps/wps-display.h
index fc40e19136..cda90ffffe 100644
--- a/apps/wps-display.h
+++ b/apps/wps-display.h
@@ -22,7 +22,18 @@
 #include <stdbool.h>
 #include "id3.h"
 
-bool wps_refresh(struct mp3entry* id3, int ffwd_offset, bool refresh_scroll);
+/* constants used in line_type and as refresh_mode for wps_refresh */
+#define WPS_REFRESH_STATIC          1    /* line doesn't change over time */
+#define WPS_REFRESH_DYNAMIC         2    /* line may change (e.g. time flag) */
+#define WPS_REFRESH_SCROLL          4    /* line scrolls */
+#define WPS_REFRESH_PLAYER_PROGRESS 8    /* line contains a progress bar */
+#define WPS_REFRESH_PEAK_METER      16   /* line contains a peak meter */
+#define WPS_REFRESH_ALL             0xff /* to refresh all line types */
+/* to refresh only those lines that change over time */
+#define WPS_REFRESH_NON_STATIC (WPS_REFRESH_ALL & ~WPS_REFRESH_STATIC & ~WPS_REFRESH_SCROLL)
+
+
+bool wps_refresh(struct mp3entry* id3, int ffwd_offset, unsigned char refresh_mode);
 bool wps_display(struct mp3entry* id3);
 bool wps_load(char* file, bool display);
 void wps_reset(void);
diff --git a/apps/wps.c b/apps/wps.c
index 3e48333818..8f9295a293 100644
--- a/apps/wps.c
+++ b/apps/wps.c
@@ -68,7 +68,7 @@ void player_change_volume(int button)
                 if(global_settings.volume > mpeg_sound_max(SOUND_VOLUME))
                     global_settings.volume = mpeg_sound_max(SOUND_VOLUME);
                 mpeg_sound_set(SOUND_VOLUME, global_settings.volume);
-                wps_refresh(id3,0,false);
+                wps_refresh(id3, 0, WPS_REFRESH_NON_STATIC);
                 settings_save();
                 break;
 
@@ -78,7 +78,7 @@ void player_change_volume(int button)
                 if(global_settings.volume < mpeg_sound_min(SOUND_VOLUME))
                     global_settings.volume = mpeg_sound_min(SOUND_VOLUME);
                 mpeg_sound_set(SOUND_VOLUME, global_settings.volume);
-                wps_refresh(id3,0,false);
+                wps_refresh(id3, 0, WPS_REFRESH_NON_STATIC);
                 settings_save();
                 break;
 
@@ -100,7 +100,7 @@ void player_change_volume(int button)
             button = button_get(true);
     }
     status_draw();
-    wps_refresh(id3,0,true);
+    wps_refresh(id3,0, WPS_REFRESH_ALL);
 }
 #endif
 
@@ -366,9 +366,9 @@ static bool ffwd_rew(int button)
                 }
 
                 if(wps_time_countup == false)
-                    wps_refresh(id3, -ff_rewind_count, false);
+                    wps_refresh(id3, -ff_rewind_count, WPS_REFRESH_PLAYER_PROGRESS);
                 else
-                    wps_refresh(id3, ff_rewind_count, false);
+                    wps_refresh(id3, ff_rewind_count, WPS_REFRESH_PLAYER_PROGRESS);
 
                 break;
 
@@ -399,7 +399,7 @@ static bool ffwd_rew(int button)
         if (!exit)
             button = button_get(true);
     }
-    wps_refresh(id3,0,true);
+    wps_refresh(id3, 0, WPS_REFRESH_ALL);
     return usb;
 }
 
@@ -415,11 +415,11 @@ static bool update(void)
         if (wps_display(id3))
             retcode = true;
         else
-            wps_refresh(id3,0,true);
+            wps_refresh(id3, 0, WPS_REFRESH_ALL);
     }
 
     if (id3)
-        wps_refresh(id3,0,false);
+        wps_refresh(id3, 0, WPS_REFRESH_NON_STATIC);
 
     status_draw();
 
@@ -453,7 +453,7 @@ static bool keylock(void)
 #endif
     display_keylock_text(true);
     keys_locked = true;
-    wps_refresh(id3,0,true);
+    wps_refresh(id3, 0, WPS_REFRESH_ALL);
     if (wps_display(id3)) {
         keys_locked = false;
 #ifdef HAVE_LCD_CHARCELLS
@@ -511,7 +511,7 @@ static bool keylock(void)
             default:
                 display_keylock_text(true);
                 while (button_get(false)); /* clear button queue */
-                wps_refresh(id3,0,true);
+                wps_refresh(id3, 0, WPS_REFRESH_ALL);
                 if (wps_display(id3)) {
                     keys_locked = false;
 #ifdef HAVE_LCD_CHARCELLS
@@ -628,7 +628,7 @@ static bool menu(void)
 #endif
 
     wps_display(id3);
-    wps_refresh(id3,0,true);
+    wps_refresh(id3, 0, WPS_REFRESH_ALL);
     return false;
 }
 
@@ -659,7 +659,7 @@ int wps_show(void)
         if (id3) {
             if (wps_display(id3))
                 return 0;
-            wps_refresh(id3,0,true);
+            wps_refresh(id3, 0, WPS_REFRESH_ALL);
         }
         restore = true;
     }
@@ -674,14 +674,44 @@ int wps_show(void)
             isn't displayed */
         if (peak_meter_enabled) {
             int i;
+
+            /* In high performance mode we read out the mas as
+               often as we can. There is no sleep for cpu */
+            if (global_settings.peak_meter_performance) {
+                long next_refresh = current_tick;
+                long next_big_refresh = current_tick + HZ / 5;
+                button = BUTTON_NONE;
+                while (!TIME_AFTER(current_tick, next_big_refresh)) {
+                    button = button_get(false);
+                    if (button != BUTTON_NONE) {
+                        break;
+                    }
+                    peak_meter_peek();
+                    yield();
+
+                    if (TIME_AFTER(current_tick, next_refresh)) {
+                        wps_refresh(id3, 0, WPS_REFRESH_PEAK_METER);
+                        next_refresh = current_tick + HZ / peak_meter_fps;
+                    }
+                }
+            } 
+            
+            /* In energy saver mode the cpu may sleep a 
+               little bit while waiting for buttons */
+            else {
             for (i = 0; i < 4; i++) {
-                button = button_get_w_tmo(HZ / 20);
+                    button = button_get_w_tmo(HZ / peak_meter_fps);
                 if (button != 0) {
                     break;
                 }
-                wps_refresh(id3, 0, false);
+                    wps_refresh(id3, 0, WPS_REFRESH_PEAK_METER);
+                }
             }
-        } else {
+        } 
+        
+        /* The peak meter is disabled 
+           -> no additional screen updates needed */
+        else {
             button = button_get_w_tmo(HZ/5);
         }
 #else
@@ -880,7 +910,7 @@ int wps_show(void)
             if (wps_display(id3))
                 return 0;
             if (id3)
-                wps_refresh(id3,0,false);
+                wps_refresh(id3, 0, WPS_REFRESH_NON_STATIC);
         }
         if(button != BUTTON_NONE)
             lastbutton = button;