diff --git a/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java b/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java
index 2c188e6..d7c6301 100644
--- a/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java
+++ b/src/main/java/cc/sukazyo/cono/morny/GradleProjectConfigures.java
@@ -6,5 +6,5 @@ package cc.sukazyo.cono.morny;
 public class GradleProjectConfigures {
 	public static final String VERSION = "0.8.0.8";
 	public static final String CODENAME = "putian";
-	public static final long COMPILE_TIMESTAMP = 1665999835121L;
+	public static final long COMPILE_TIMESTAMP = 1666028272898L;
 }
diff --git a/src/main/java/cc/sukazyo/cono/morny/util/BiliTool.java b/src/main/java/cc/sukazyo/cono/morny/util/BiliTool.java
new file mode 100644
index 0000000..b222828
--- /dev/null
+++ b/src/main/java/cc/sukazyo/cono/morny/util/BiliTool.java
@@ -0,0 +1,38 @@
+package cc.sukazyo.cono.morny.util;
+
+import javax.annotation.Nonnegative;
+import javax.annotation.Nonnull;
+import java.util.HashMap;
+import java.util.Map;
+
+public class BiliTool {
+	
+	private static final long V_CONV_XOR = 177451812L;
+	private static final long V_CONV_ADD = 8728348608L;
+	private static final char[] BV_TABLE = "fZodR9XQDSUm21yCkr6zBqiveYah8bt4xsWpHnJE7jL5VG3guMTKNPAwcF".toCharArray();
+	private static final int TABLE_INT = BV_TABLE.length;
+	private static final Map<Character, Integer> BV_TABLE_REVERSED = new HashMap<>();
+	static { for (int i = 0; i < BV_TABLE.length; i++) BV_TABLE_REVERSED.put(BV_TABLE[i], i); }
+	private static final char[] BV_TEMPLATE = "1  4 1 7  ".toCharArray();
+	private static final int[] BV_TEMPLATE_FILTER = new int[]{9, 8, 1, 6, 2, 4};
+	
+	@Nonnegative
+	public static long toAv (@Nonnull String bv) {
+		long av = 0;
+		for (int i = 0; i < BV_TEMPLATE_FILTER.length; i++) {
+			av += BV_TABLE_REVERSED.get(bv.charAt(BV_TEMPLATE_FILTER[i])) * Math.pow(TABLE_INT,i);
+		}
+		return (av-V_CONV_ADD)^V_CONV_XOR;
+	}
+	
+	@Nonnull
+	public static String toBv (@Nonnegative long av) {
+		av = (av^V_CONV_XOR)+V_CONV_ADD;
+		final char[] bv = BV_TEMPLATE.clone();
+		for (int i = 0; i < BV_TEMPLATE_FILTER.length; i++) {
+			bv[BV_TEMPLATE_FILTER[i]] = BV_TABLE[(int)(Math.floor(av/(Math.pow(TABLE_INT, i)))%TABLE_INT)];
+		}
+		return String.copyValueOf(bv);
+	}
+	
+}
diff --git a/src/test/java/cc/sukazyo/cono/morny/util/TestBiliTool.java b/src/test/java/cc/sukazyo/cono/morny/util/TestBiliTool.java
new file mode 100644
index 0000000..125d9c6
--- /dev/null
+++ b/src/test/java/cc/sukazyo/cono/morny/util/TestBiliTool.java
@@ -0,0 +1,30 @@
+package cc.sukazyo.cono.morny.util;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+import static cc.sukazyo.cono.morny.util.BiliTool.*;
+
+public class TestBiliTool {
+	
+	private static final String AV_BV_DATA_CSV = """
+			17x411w7KC, 170001
+			1Q541167Qg, 455017605
+			1mK4y1C7Bz, 882584971
+			1T24y197V2, 688730800
+			""";
+	
+	@ParameterizedTest
+	@CsvSource(textBlock = AV_BV_DATA_CSV)
+	void testAvToBv (String bv, int av) {
+		Assertions.assertEquals(bv, toBv(av));
+	}
+	
+	@ParameterizedTest
+	@CsvSource(textBlock = AV_BV_DATA_CSV)
+	void testBvToAv (String bv, int av) {
+		Assertions.assertEquals(av, toAv(bv));
+	}
+	
+}