Document the TIFF image functions. Correct related documentation.

5 files changed, 19 insertions, 11 deletions

diff --git a/README.md b/README.md
index 96dfc33..94974ff 100644
--- a/README.md
+++ b/README.md
@@ -14,7 +14,7 @@ text, drawing and images.
 * Choice of measurement unit, page format and margins
 * Page header and footer management
 * Automatic page breaks, line breaks, and text justification
-* Inclusion of JPEG, PNG, GIF and basic path-only SVG images
+* Inclusion of JPEG, PNG, GIF, TIFF and basic path-only SVG images
 * Colors, gradients and alpha channel transparency
 * Outline bookmarks
 * Internal and external links
diff --git a/compare.go b/compare.go
index edc1ae4..416e545 100644
--- a/compare.go
+++ b/compare.go
@@ -113,9 +113,8 @@ func CompareBytes(sl1, sl2 []byte) (err error) {
 }
 
 // ComparePDFs reads and compares the full contents of the two specified
-// readers. The comparison is done byte-for-byte with the exception of the
-// CreationDate fields which are effectively ignored. Nil is returned if the
-// buffers are equal, otherwise an error.
+// readers byte-for-byte. Nil is returned if the buffers are equal, otherwise
+// an error.
 func ComparePDFs(rdr1, rdr2 io.Reader) (err error) {
 	var b1, b2 *bytes.Buffer
 	_, err = b1.ReadFrom(rdr1)
@@ -129,10 +128,8 @@ func ComparePDFs(rdr1, rdr2 io.Reader) (err error) {
 }
 
 // ComparePDFFiles reads and compares the full contents of the two specified
-// files. The comparison is done byte-for-byte with the exception of the
-// CreationDate fields which are effectively ignored. Nil is returned if the
-// file contents are equal, or if the second file is missing, otherwise an
-// error.
+// files byte-for-byte. Nil is returned if the file contents are equal, or if
+// the second file is missing, otherwise an error.
 func ComparePDFFiles(file1Str, file2Str string) (err error) {
 	var sl1, sl2 []byte
 	sl1, err = ioutil.ReadFile(file1Str)
diff --git a/contrib/tiff/tiff.go b/contrib/tiff/tiff.go
index 5bc34d9..3f13a38 100644
--- a/contrib/tiff/tiff.go
+++ b/contrib/tiff/tiff.go
@@ -30,7 +30,12 @@ import (
 	"golang.org/x/image/tiff"
 )
 
-// RegisterReader ...
+// RegisterReader registers a TIFF image, adding it to the PDF file but not
+// adding it to the page. imgName specifies the name that will be used in the
+// call to Image() that actually places the image in the document. options
+// specifies various image properties; in this case, the ImageType property
+// should be set to "tiff". The TIFF image is a reader from the reader
+// specified by r.
 func RegisterReader(fpdf *gofpdf.Fpdf, imgName string, options gofpdf.ImageOptions, r io.Reader) (info *gofpdf.ImageInfoType) {
 	var err error
 	var img image.Image
@@ -55,7 +60,12 @@ func RegisterReader(fpdf *gofpdf.Fpdf, imgName string, options gofpdf.ImageOptio
 	return
 }
 
-// RegisterFile ...
+// RegisterFile registers a TIFF image, adding it to the PDF file but not
+// adding it to the page. imgName specifies the name that will be used in the
+// call to Image() that actually places the image in the document. options
+// specifies various image properties; in this case, the ImageType property
+// should be set to "tiff". The TIFF image is read from the file specified by
+// tiffFileStr.
 func RegisterFile(fpdf *gofpdf.Fpdf, imgName string, options gofpdf.ImageOptions, tiffFileStr string) (info *gofpdf.ImageInfoType) {
 	var f *os.File
 	var err error
diff --git a/contrib/tiff/tiff_test.go b/contrib/tiff/tiff_test.go
index d222375..33b294b 100644
--- a/contrib/tiff/tiff_test.go
+++ b/contrib/tiff/tiff_test.go
@@ -6,6 +6,7 @@ import (
 	"github.com/jung-kurt/gofpdf/internal/example"
 )
 
+// ExampleRegisterFile demonstrates the loading and display of a TIFF image.
 func ExampleRegisterFile() {
 	pdf := gofpdf.New("L", "mm", "A4", "")
 	pdf.SetFont("Helvetica", "", 12)
diff --git a/doc.go b/doc.go
index d9302c3..a0af537 100644
--- a/doc.go
+++ b/doc.go
@@ -26,7 +26,7 @@ Features
 
 • Automatic page breaks, line breaks, and text justification
 
-• Inclusion of JPEG, PNG, GIF and basic path-only SVG images
+• Inclusion of JPEG, PNG, GIF, TIFF and basic path-only SVG images
 
 • Colors, gradients and alpha channel transparency