diff --git a/formats/dcc/direction.go b/formats/dcc/direction.go
index 6b6188a..06b4b90 100644
--- a/formats/dcc/direction.go
+++ b/formats/dcc/direction.go
@@ -19,13 +19,7 @@ type directionHeader struct {
 	CodedBytesBits      uint8
 }
 
-type direction struct {
-	header directionHeader
-	frames []frame
-	bounds bounds
-}
-
-func readDirectionHeader(bitReader *streaming.BitReader) directionHeader {
+func readDirectionHeader(bitReader *streaming.BitReader) (*directionHeader, error) {
 	var dirHead directionHeader
 
 	dirHead.CodedSize = uint32(bitReader.ReadUint(32))
@@ -39,18 +33,22 @@ func readDirectionHeader(bitReader *streaming.BitReader) directionHeader {
 	dirHead.OptionalBytesBits = uint8(bitReader.ReadUint(4))
 	dirHead.CodedBytesBits = uint8(bitReader.ReadUint(4))
 
-	return dirHead
+	if err := bitReader.Error(); err != nil {
+		return nil, err
+	}
+
+	return &dirHead, nil
 }
 
 func readDirection(reader io.ReadSeeker, fileHead fileHeader) (*direction, error) {
 	bitReader := streaming.NewBitReader(reader)
 
-	dirHead := readDirectionHeader(bitReader)
-	if err := bitReader.Error(); err != nil {
+	dirHead, err := readDirectionHeader(bitReader)
+	if err != nil {
 		return nil, err
 	}
 
-	frameHeads, err := readFrameHeaders(bitReader, fileHead, dirHead)
+	frameHeads, err := readFrameHeaders(bitReader, fileHead, *dirHead)
 	if err != nil {
 		return nil, err
 	}
@@ -89,12 +87,12 @@ func readDirection(reader io.ReadSeeker, fileHead fileHeader) (*direction, error
 
 	var entries []pixelBufferEntry
 
-	entries, err = decodeDirectionStage1(bitReader, &dirData, entries)
+	entries, err = dirData.decodeStage1(bitReader, entries)
 	if err != nil {
 		return nil, err
 	}
 
-	entries, err = decodeDirectionStage2(bitReader, &dirData, entries)
+	entries, err = dirData.decodeStage2(bitReader, entries)
 	if err != nil {
 		return nil, err
 	}
@@ -102,10 +100,16 @@ func readDirection(reader io.ReadSeeker, fileHead fileHeader) (*direction, error
 	return &dirData, nil
 }
 
-func decodeDirectionStage1(bitReader *streaming.BitReader, dirData *direction, entries []pixelBufferEntry) ([]pixelBufferEntry, error) {
+type direction struct {
+	header directionHeader
+	frames []frame
+	bounds bounds
+}
+
+func (d *direction) decodeStage1(bitReader *streaming.BitReader, entries []pixelBufferEntry) ([]pixelBufferEntry, error) {
 	return nil, nil
 }
 
-func decodeDirectionStage2(bitReader *streaming.BitReader, dirData *direction, entries []pixelBufferEntry) ([]pixelBufferEntry, error) {
+func (d *direction) decodeStage2(bitReader *streaming.BitReader, entries []pixelBufferEntry) ([]pixelBufferEntry, error) {
 	return nil, nil
 }
diff --git a/formats/dcc/frame.go b/formats/dcc/frame.go
index 8464354..563a730 100644
--- a/formats/dcc/frame.go
+++ b/formats/dcc/frame.go
@@ -22,7 +22,7 @@ type frame struct {
 	bounds bounds
 }
 
-func readFrameHeader(bitReader *streaming.BitReader, dirHead directionHeader) frameHeader {
+func readFrameHeader(bitReader *streaming.BitReader, dirHead directionHeader) (*frameHeader, error) {
 	var frameHead frameHeader
 
 	frameHead.Variable0 = uint32(bitReader.ReadUintPacked(int(dirHead.Variable0Bits)))
@@ -34,30 +34,34 @@ func readFrameHeader(bitReader *streaming.BitReader, dirHead directionHeader) fr
 	frameHead.CodedBytes = uint32(bitReader.ReadUintPacked(int(dirHead.CodedBytesBits)))
 	frameHead.FrameBottomUp = bitReader.ReadBool()
 
-	return frameHead
+	if err := bitReader.Error(); err != nil {
+		return nil, err
+	}
+
+	if frameHead.OptionalBytes != 0 {
+		return nil, errors.New("optional frame data not supported")
+	}
+
+	if frameHead.FrameBottomUp {
+		return nil, errors.New("bottom-up frames are not supported")
+	}
+
+	if frameHead.Width == 0 || frameHead.Height == 0 {
+		return nil, errors.New("invalid frame dimensions")
+	}
+
+	return &frameHead, nil
 }
 
 func readFrameHeaders(bitReader *streaming.BitReader, fileHead fileHeader, dirHead directionHeader) ([]frameHeader, error) {
 	var frameHeads []frameHeader
 	for i := 0; i < int(fileHead.FramesPerDir); i++ {
-		frameHead := readFrameHeader(bitReader, dirHead)
-		if err := bitReader.Error(); err != nil {
+		frameHead, err := readFrameHeader(bitReader, dirHead)
+		if err != nil {
 			return nil, err
 		}
 
-		if frameHead.OptionalBytes != 0 {
-			return nil, errors.New("optional frame data not supported")
-		}
-
-		if frameHead.FrameBottomUp {
-			return nil, errors.New("bottom-up frames are not supported")
-		}
-
-		if frameHead.Width == 0 || frameHead.Height == 0 {
-			return nil, errors.New("invalid frame dimensions")
-		}
-
-		frameHeads = append(frameHeads, frameHead)
+		frameHeads = append(frameHeads, *frameHead)
 	}
 
 	return frameHeads, nil