update flac errors

flac/errors.go

@@ -3,14 +3,14 @@ package flac
 import "errors"
 
 var (
-	ErrorNotVorbisComment = errors.New("Not a vorbis comment metadata block")
-	ErrorUnexpEof         = errors.New("Unexpected end of stream")
-	ErrorMalformedComment = errors.New("Malformed comment")
-	ErrorInvalidFieldName = errors.New("Malformed Field Name")
+	ErrorNotVorbisComment = errors.New("not a vorbis comment metadata block")
+	ErrorUnexpEof         = errors.New("unexpected end of stream")
+	ErrorMalformedComment = errors.New("malformed comment")
+	ErrorInvalidFieldName = errors.New("malformed field Name")
 	// ErrorNotPictureMetadataBlock is returned if the metadata provided is not a picture block.
-	ErrorNotPictureMetadataBlock = errors.New("Not a picture metadata block")
+	ErrorNotPictureMetadataBlock = errors.New("not a picture metadata block")
 	// ErrorUnsupportedMIME is returned if the provided image MIME type is unsupported.
-	ErrorUnsupportedMIME = errors.New("Unsupported MIME")
+	ErrorUnsupportedMIME = errors.New("unsupported MIME")
 	// ErrorNoFLACHeader indicates that "fLaC" marker not found at the beginning of the file
 	ErrorNoFLACHeader = errors.New("fLaC head incorrect")
 	// ErrorNoStreamInfo indicates that StreamInfo Metablock not present or is not the first Metablock

flac/flacfile.go

@@ -3,7 +3,6 @@ package flac
 import (
 	"bytes"
 	"io"
-	"io/ioutil"
 	"os"
 )
 
@@ -27,7 +26,7 @@ func (c *File) Marshal() []byte {
 
 // Save encapsulates Marshal and save the file to the file system
 func (c *File) Save(fn string) error {
-	return ioutil.WriteFile(fn, c.Marshal(), 0644)
+	return os.WriteFile(fn, c.Marshal(), 0644)
 }
 
 // ParseMetadata accepts a reader to a FLAC stream and consumes only FLAC metadata

flac/picture.go

@@ -2,6 +2,8 @@ package flac
 
 import (
 	"bytes"
+	"image/jpeg"
+	"image/png"
 )
 
 // PictureType defines the type of this image
@@ -132,3 +134,32 @@ func ParsePicFromMetaDataBlock(meta MetaDataBlock) (*MetadataBlockPicture, error
 
 	return res, nil
 }
+
+// ParsePicture decodes the image and inflated the Width, Height, ColorDepth, IndexedColorCount fields. This is called automatically by NewFromImageData
+func (c *MetadataBlockPicture) ParsePicture() error {
+	switch c.MIME {
+	case "image/jpeg":
+		img, err := jpeg.Decode(bytes.NewReader(c.ImageData))
+		if err != nil {
+			return err
+		}
+		c.IndexedColorCount = uint32(0)
+		size := img.Bounds()
+		c.Width = uint32(size.Max.X)
+		c.Height = uint32(size.Max.Y)
+		c.ColorDepth = uint32(24)
+	case "image/png":
+		img, err := png.Decode(bytes.NewReader(c.ImageData))
+		if err != nil {
+			return err
+		}
+		c.IndexedColorCount = uint32(0)
+		size := img.Bounds()
+		c.Width = uint32(size.Max.X)
+		c.Height = uint32(size.Max.Y)
+		c.ColorDepth = uint32(32)
+	default:
+		return ErrorUnsupportedMIME
+	}
+	return nil
+}

flac/streamdata.go

@@ -5,6 +5,8 @@ import (
 	"io"
 )
 
+type FrameData []byte
+
 // StreamInfoBlock represents the undecoded data of StreamInfo block
 type StreamInfoBlock struct {
 	// BlockSizeMin The minimum block size (in samples) used in the stream.

go.mod

@@ -6,7 +6,6 @@ require (
 	github.com/abema/go-mp4 v1.2.0
 	github.com/aler9/writerseeker v1.1.0
 	github.com/bogem/id3v2/v2 v2.1.4
-	github.com/orcaman/writerseeker v0.0.0-20200621085525-1d3f536ff85e
 	github.com/sunfish-shogi/bufseekio v0.1.0
 )