暂时使用星下点坐标作为图像左上角坐标

pkg/auxilary/util.go

@@ -0,0 +1,51 @@
+package auxilary
+
+import (
+	"bytes"
+	"encoding/binary"
+)
+
+// int32ToBigEndian converts an int32 to a big-endian byte array.
+func int32ToBigEndian(num int32) ([]byte, error) {
+	buf := new(bytes.Buffer)
+	err := binary.Write(buf, binary.BigEndian, num)
+	if err != nil {
+		return nil, err
+	}
+	return buf.Bytes(), nil
+}
+
+// bigEndianToInt32 converts a big-endian byte array to an int32.
+func bigEndianToInt32(data []byte) int32 {
+	var num int32
+	buf := bytes.NewReader(data)
+	err := binary.Read(buf, binary.BigEndian, &num)
+	if err != nil {
+		return 0
+	}
+	return num
+}
+
+// bigEndianToInt24 converts a big-endian 3-byte array to an int32 (simulating int24).
+func bigEndianToInt24(data []byte) int32 {
+	if len(data) != 3 {
+		return 0
+	}
+	num := int32(data[0])<<16 | int32(data[1])<<8 | int32(data[2])
+	// Adjust for negative values
+	if num&0x800000 != 0 {
+		num |= ^0xFFFFFF
+	}
+	return num
+}
+
+// bigEndianToInt16 converts a big-endian byte array to an int16.
+func bigEndianToInt16(data []byte) int16 {
+	var num int16
+	buf := bytes.NewReader(data)
+	err := binary.Read(buf, binary.BigEndian, &num)
+	if err != nil {
+		return 0
+	}
+	return num
+}