Changeset 380 for dsfilters/demux_mpc/src/mpc_file.cpp

Timestamp:

01/05/08 20:49:27 (16 years ago)

Author:

radscorpion

Message:

Fixed SV7 seeking artifacts. Fixed gain info.

File:

• dsfilters/demux_mpc/src/mpc_file.cpp (modified) (5 diffs)

dsfilters/demux_mpc/src/mpc_file.cpp

@@ -8 +8 @@
 #include "stdafx.h"
 #include <math.h>
+
+#define OLD_GAIN_REF            64.82
 
 
@@ -164 +166 @@
 
         b.NeedBits32();
-        gain_title_db = b.SGetBits(16) / 100.0;         // title gain
+        gain_title_db = ((int16)b.SGetBits(16)) / 100.0;                // title gain
         int title_peak = b.UGetBits(16);
-        if (title_peak != 0) {
-                gain_title_peak_db = 20 * log10f((float)title_peak);            // title peak
+        if (title_peak != 0) {          
+                gain_title_peak_db = (title_peak / 32767.0);
         } else {
                 gain_title_peak_db = 0;
@@ -173 +175 @@
 
         b.NeedBits32();
-        gain_album_db = b.SGetBits(16) / 100.0;         // album gain
+        gain_album_db = ((int16)b.SGetBits(16)) / 100.0;                // album gain
         int album_peak = b.UGetBits(16);
         if (album_peak != 0) {
-                gain_album_peak_db = 20 * log10f((float)album_peak);            // album peak
+                gain_album_peak_db = (album_peak / 32767.0);
         } else {
                 gain_album_peak_db = 0;
         }
 
-        #define OLD_GAIN_REF            64.82
-        if (gain_title_db != 0) {
-                gain_title_db = OLD_GAIN_REF - gain_title_db;
-        }
-        if (gain_album_db != 0) {
-                gain_album_db = OLD_GAIN_REF - gain_album_db;
-        }
 
         b.NeedBits32();
@@ -300 +295 @@
         int16   val;
         b.NeedBits();   val = b.SGetBits(16);   gain_title_db = val / 256.0;
-        b.NeedBits();   val = b.SGetBits(16);   gain_title_peak_db = val / 256.0;
+        b.NeedBits();   val = b.UGetBits(16);   gain_title_peak_db = val;
         b.NeedBits();   val = b.SGetBits(16);   gain_album_db = val / 256.0;
-        b.NeedBits();   val = b.SGetBits(16);   gain_album_peak_db = val / 256.0;
+        b.NeedBits();   val = b.UGetBits(16);   gain_album_peak_db = val;
+
+        if (gain_title_db != 0) gain_title_db = OLD_GAIN_REF - gain_title_db;
+        if (gain_album_db != 0) gain_album_db = OLD_GAIN_REF - gain_album_db;
+        if (gain_title_peak_db != 0) {
+                gain_title_peak_db = pow((double)10.0, (double)(gain_title_peak_db / (20*256))) / (double)(1 << 15);
+        }
+        if (gain_album_peak_db != 0) {
+                gain_album_peak_db = pow((double)10.0, (double)(gain_album_peak_db / (20*256))) / (double)(1 << 15);
+        }
 
         return 0;
@@ -480 +484 @@
 
         int packet_num = seek_sample / (1152*audio_block_frames);
+
+        // we need to seek back a little to avoid artifacts
+        if (stream_version == 7) {
+                if (packet_num > 32) {
+                        packet_num -= 32;
+                } else {
+                        packet_num = 0;
+                }
+        }
+
         int i = (packet_num >> (seek_pwr - block_pwr));
         if (i >= seek_table_size) {
                 i = seek_table_size-1;
         }
+
 
         // seek to position