diff --git a/.gitignore b/.gitignore
index f32e31a..4a62f47 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 .idea/
 .DS_Store
+pdf_test.go
diff --git a/README.md b/README.md
index 477408c..2b01429 100644
--- a/README.md
+++ b/README.md
@@ -8,7 +8,7 @@ Features
 
 ## Install:
 
-`go get -u github.com/ledongthuc/pdf`
+`go get -u github.com/dslipak/pdf`
 
 
 ## Read plain text
@@ -20,7 +20,7 @@ import (
 	"bytes"
 	"fmt"
 
-	"github.com/ledongthuc/pdf"
+	"github.com/dslipak/pdf"
 )
 
 func main() {
@@ -92,7 +92,7 @@ import (
 	"fmt"
 	"os"
 
-	"github.com/dcu/pdf"
+	"github.com/dslipak/pdf"
 )
 
 func main() {
diff --git a/lex.go b/lex.go
index ee73fd9..652e18b 100644
--- a/lex.go
+++ b/lex.go
@@ -7,6 +7,7 @@
 package pdf
 
 import (
+	"errors"
 	"fmt"
 	"io"
 	"strconv"
@@ -78,11 +79,12 @@ func (b *buffer) readByte() byte {
 	return c
 }
 
-func (b *buffer) errorf(format string, args ...interface{}) {
-	panic(fmt.Errorf(format, args...))
+func (b *buffer) errorf(format string, args ...interface{}) string {
+	// panic(fmt.Errorf(format, args...))
+	return fmt.Sprintf(format, args...)
 }
 
-func (b *buffer) reload() bool {
+func (b *buffer) reload() (bool, error) {
 	n := cap(b.buf) - int(b.offset%int64(cap(b.buf)))
 	n, err := b.r.Read(b.buf[:n])
 	if n == 0 && err != nil {
@@ -90,24 +92,29 @@ func (b *buffer) reload() bool {
 		b.pos = 0
 		if b.allowEOF && err == io.EOF {
 			b.eof = true
-			return false
+			return false, err
 		}
-		b.errorf("malformed PDF: reading at offset %d: %v", b.offset, err)
-		return false
+		fmt.Sprint(b.errorf("malformed PDF: reading at offset %d: %v", b.offset, err))
+		return false, err
 	}
 	b.offset += int64(n)
 	b.buf = b.buf[:n]
 	b.pos = 0
-	return true
+	return true, err
 }
 
-func (b *buffer) seekForward(offset int64) {
+func (b *buffer) seekForward(offset int64) (err error) {
 	for b.offset < offset {
-		if !b.reload() {
-			return
+		rel, err := b.reload()
+		if err != nil {
+			return err
+		}
+		if !rel {
+			return err
 		}
 	}
 	b.pos = len(b.buf) - int(b.offset-offset)
+	return err
 }
 
 func (b *buffer) readOffset() int64 {
@@ -160,7 +167,7 @@ func (b *buffer) readToken() token {
 		return b.readLiteralString()
 
 	case '[', ']', '{', '}':
-		return keyword(string(c))
+		return keyword(c)
 
 	case '/':
 		return b.readName()
@@ -174,8 +181,9 @@ func (b *buffer) readToken() token {
 
 	default:
 		if isDelim(c) {
-			b.errorf("unexpected delimiter %#q", rune(c))
-			return nil
+			// b.errorf("unexpected delimiter %#q", rune(c))
+			return b.errorf("unexpected delimiter %#q", rune(c))
+			// return nil
 		}
 		b.unreadByte()
 		return b.readKeyword()
@@ -200,7 +208,7 @@ func (b *buffer) readHexString() token {
 		}
 		x := unhex(c)<<4 | unhex(c2)
 		if x < 0 {
-			b.errorf("malformed hex string %c %c %s", c, c2, b.buf[b.pos:])
+			fmt.Sprint(b.errorf("malformed hex string %c %c %s", c, c2, b.buf[b.pos:]))
 			break
 		}
 		tmp = append(tmp, byte(x))
@@ -241,7 +249,8 @@ Loop:
 		case '\\':
 			switch c = b.readByte(); c {
 			default:
-				b.errorf("invalid escape sequence \\%c", c)
+				// b.errorf("invalid escape sequence \\%c", c)
+				fmt.Sprint(b.errorf("invalid escape sequence \\%c", c))
 				tmp = append(tmp, '\\', c)
 			case 'n':
 				tmp = append(tmp, '\n')
@@ -294,7 +303,8 @@ func (b *buffer) readName() token {
 		if c == '#' {
 			x := unhex(b.readByte())<<4 | unhex(b.readByte())
 			if x < 0 {
-				b.errorf("malformed name")
+				// b.errorf("malformed name")
+				fmt.Sprint(b.errorf("malformed name"))
 			}
 			tmp = append(tmp, byte(x))
 			continue
@@ -325,13 +335,15 @@ func (b *buffer) readKeyword() token {
 	case isInteger(s):
 		x, err := strconv.ParseInt(s, 10, 64)
 		if err != nil {
-			b.errorf("invalid integer %s", s)
+			// b.errorf("invalid integer %s", s)
+			fmt.Sprint(b.errorf("invalid integer %s", s))
 		}
 		return x
 	case isReal(s):
 		x, err := strconv.ParseFloat(s, 64)
 		if err != nil {
-			b.errorf("invalid real %s", s)
+			// b.errorf("invalid real %s", s)
+			fmt.Sprint(b.errorf("invalid real %s", s))
 		}
 		return x
 	}
@@ -409,19 +421,20 @@ type objdef struct {
 	obj object
 }
 
-func (b *buffer) readObject() object {
+func (b *buffer) readObject() (object, error) {
 	tok := b.readToken()
 	if kw, ok := tok.(keyword); ok {
 		switch kw {
 		case "null":
-			return nil
+			return nil, nil
 		case "<<":
-			return b.readDict()
+			return b.readDict(), nil
 		case "[":
-			return b.readArray()
+			return b.readArray(), nil
 		}
-		b.errorf("unexpected keyword %q parsing object", kw)
-		return nil
+		// b.errorf("unexpected keyword %q parsing object", kw)
+		return nil, errors.New(b.errorf("unexpected keyword %q parsing object", kw))
+		// return nil
 	}
 
 	if str, ok := tok.(string); ok && b.key != nil && b.objptr.id != 0 {
@@ -429,7 +442,7 @@ func (b *buffer) readObject() object {
 	}
 
 	if !b.allowObjptr {
-		return tok
+		return tok, nil
 	}
 
 	if t1, ok := tok.(int64); ok && int64(uint32(t1)) == t1 {
@@ -438,26 +451,30 @@ func (b *buffer) readObject() object {
 			tok3 := b.readToken()
 			switch tok3 {
 			case keyword("R"):
-				return objptr{uint32(t1), uint16(t2)}
+				return objptr{uint32(t1), uint16(t2)}, nil
 			case keyword("obj"):
 				old := b.objptr
 				b.objptr = objptr{uint32(t1), uint16(t2)}
-				obj := b.readObject()
+				obj, err := b.readObject()
+				if err != nil {
+					return nil, err
+				}
 				if _, ok := obj.(stream); !ok {
 					tok4 := b.readToken()
 					if tok4 != keyword("endobj") {
-						b.errorf("missing endobj after indirect object definition")
+						// b.errorf("missing endobj after indirect object definition")
+						fmt.Sprint(b.errorf("missing endobj after indirect object definition"))
 						b.unreadToken(tok4)
 					}
 				}
 				b.objptr = old
-				return objdef{objptr{uint32(t1), uint16(t2)}, obj}
+				return objdef{objptr{uint32(t1), uint16(t2)}, obj}, err
 			}
 			b.unreadToken(tok3)
 		}
 		b.unreadToken(tok2)
 	}
-	return tok
+	return tok, nil
 }
 
 func (b *buffer) readArray() object {
@@ -468,7 +485,11 @@ func (b *buffer) readArray() object {
 			break
 		}
 		b.unreadToken(tok)
-		x = append(x, b.readObject())
+		res, err := b.readObject()
+		if err != nil {
+			return err
+		}
+		x = append(x, res)
 	}
 	return x
 }
@@ -482,10 +503,15 @@ func (b *buffer) readDict() object {
 		}
 		n, ok := tok.(name)
 		if !ok {
-			b.errorf("unexpected non-name key %T(%v) parsing dictionary", tok, tok)
+			// b.errorf("unexpected non-name key %T(%v) parsing dictionary", tok, tok)
+			fmt.Sprint(b.errorf("unexpected non-name key %T(%v) parsing dictionary", tok, tok))
 			continue
 		}
-		x[n] = b.readObject()
+		res, err := b.readObject()
+		if err != nil {
+			return nil
+		}
+		x[n] = res
 	}
 
 	if !b.allowStream {
@@ -506,7 +532,8 @@ func (b *buffer) readDict() object {
 	case '\n':
 		// ok
 	default:
-		b.errorf("stream keyword not followed by newline")
+		// b.errorf("stream keyword not followed by newline")
+		return b.errorf("stream keyword not followed by newline")
 	}
 
 	return stream{x, b.objptr, b.readOffset()}
diff --git a/pdf_test.go b/pdf_test.go
new file mode 100644
index 0000000..345ee95
--- /dev/null
+++ b/pdf_test.go
@@ -0,0 +1,48 @@
+package pdf
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+)
+
+const testFile = "/Users/dslipak/Documents/dslipak-20190925.pdf"
+
+func TestReadPdf(t *testing.T) {
+	f, err := Open(testFile)
+	if err != nil {
+		t.Error("Doc should not be nil', got ", err)
+	}
+
+	totalPage := f.NumPage()
+	var buf bytes.Buffer
+
+	for pageIndex := 1; pageIndex <= totalPage; pageIndex++ {
+		p := f.Page(pageIndex)
+		if p.V.IsNull() {
+			continue
+		}
+
+		texts := p.Content().Text
+		var lastY = 0.0
+		line := ""
+
+		for _, text := range texts {
+			if lastY != text.Y {
+				if lastY > 0 {
+					buf.WriteString(line + "\n")
+					line = text.S
+				} else {
+					line += text.S
+				}
+			} else {
+				line += text.S
+			}
+
+			lastY = text.Y
+		}
+		buf.WriteString(line)
+	}
+	fmt.Println(buf.String())
+}
+
diff --git a/pdfpasswd/main.go b/pdfpasswd/main.go
deleted file mode 100644
index 57fa88f..0000000
--- a/pdfpasswd/main.go
+++ /dev/null
@@ -1,110 +0,0 @@
-// Copyright 2014 The Go Authors.  All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Pdfpasswd searches for the password for an encrypted PDF
-// by trying all strings over a given alphabet up to a given length.
-package main
-
-import (
-	"flag"
-	"fmt"
-	"log"
-	"os"
-
-	"github.com/ledongthuc/pdf"
-)
-
-var (
-	alphabet  = flag.String("a", "0123456789", "alphabet")
-	maxLength = flag.Int("m", 4, "max length")
-)
-
-func usage() {
-	fmt.Fprintf(os.Stderr, "usage: pdfpasswd [-a alphabet] [-m maxlength] file\n")
-	os.Exit(2)
-}
-
-func main() {
-	log.SetFlags(0)
-	log.SetPrefix("pdfpasswd: ")
-
-	flag.Usage = usage
-	flag.Parse()
-	if flag.NArg() != 1 {
-		usage()
-	}
-
-	f, err := os.Open(flag.Arg(0))
-	if err != nil {
-		log.Fatal(err)
-	}
-
-	last := ""
-	alpha := *alphabet
-	ctr := make([]int, *maxLength)
-	pw := func() string {
-		inc(ctr, len(alpha)+1)
-		for !valid(ctr) {
-			inc(ctr, len(alpha)+1)
-		}
-		if done(ctr) {
-			return ""
-		}
-		buf := make([]byte, len(ctr))
-		var i int
-		for i = 0; i < len(buf); i++ {
-			if ctr[i] == 0 {
-				break
-			}
-			buf[i] = alpha[ctr[i]-1]
-		}
-		last = string(buf[:i])
-		println(last)
-		return last
-	}
-	st, err := f.Stat()
-	if err != nil {
-		log.Fatal(err)
-	}
-	_, err = pdf.NewReaderEncrypted(f, st.Size(), pw)
-	if err != nil {
-		if err == pdf.ErrInvalidPassword {
-			log.Fatal("password not found")
-		}
-		log.Fatal("reading pdf: %v", err)
-	}
-	fmt.Printf("password: %q\n", last)
-}
-
-func inc(ctr []int, n int) {
-	for i := 0; i < len(ctr); i++ {
-		ctr[i]++
-		if ctr[i] < n {
-			break
-		}
-		ctr[i] = 0
-	}
-}
-
-func done(ctr []int) bool {
-	for _, x := range ctr {
-		if x != 0 {
-			return false
-		}
-	}
-	return true
-}
-
-func valid(ctr []int) bool {
-	i := len(ctr)
-	for i > 0 && ctr[i-1] == 0 {
-		i--
-	}
-	for i--; i >= 0; i-- {
-		if ctr[i] == 0 {
-			return false
-		}
-	}
-	return true
-}
diff --git a/ps.go b/ps.go
index 90c551e..c7ec20e 100644
--- a/ps.go
+++ b/ps.go
@@ -59,6 +59,7 @@ func Interpret(strm Value, do func(stk *Stack, op string)) {
 	b.allowStream = false
 	var stk Stack
 	var dicts []dict
+
 Reading:
 	for {
 		tok := b.readToken()
@@ -118,7 +119,10 @@ Reading:
 			}
 		}
 		b.unreadToken(tok)
-		obj := b.readObject()
+		obj, err := b.readObject()
+		if err != nil {
+			return
+		}
 		stk.Push(Value{nil, objptr{}, obj})
 	}
 }
diff --git a/read.go b/read.go
index da5f76f..7905639 100644
--- a/read.go
+++ b/read.go
@@ -44,7 +44,7 @@
 // the package. Equally important, traversal of other PDF data structures can be implemented
 // in other packages as needed.
 //
-package pdf // import "rsc.io/pdf"
+package pdf
 
 // BUG(rsc): The package is incomplete, although it has been used successfully on some
 // large real-world PDF files.
@@ -190,6 +190,9 @@ func NewReaderEncrypted(f io.ReaderAt, size int64, pw func() string) (*Reader, e
 
 // Trailer returns the file's Trailer value.
 func (r *Reader) Trailer() Value {
+	if r == nil {
+		return Value{}
+	}
 	return Value{r, r.trailerptr, r.trailer}
 }
 
@@ -206,7 +209,10 @@ func readXref(r *Reader, b *buffer) ([]xref, objptr, dict, error) {
 }
 
 func readXrefStream(r *Reader, b *buffer) ([]xref, objptr, dict, error) {
-	obj1 := b.readObject()
+	obj1, err := b.readObject()
+	if err != nil {
+		return nil, objptr{}, nil, err
+	}
 	obj, ok := obj1.(objdef)
 	if !ok {
 		return nil, objptr{}, nil, fmt.Errorf("malformed PDF: cross-reference table not found: %v", objfmt(obj1))
@@ -225,7 +231,7 @@ func readXrefStream(r *Reader, b *buffer) ([]xref, objptr, dict, error) {
 	}
 	table := make([]xref, size)
 
-	table, err := readXrefStreamData(r, strm, table, size)
+	table, err = readXrefStreamData(r, strm, table, size)
 	if err != nil {
 		return nil, objptr{}, nil, fmt.Errorf("malformed PDF: %v", err)
 	}
@@ -236,7 +242,10 @@ func readXrefStream(r *Reader, b *buffer) ([]xref, objptr, dict, error) {
 			return nil, objptr{}, nil, fmt.Errorf("malformed PDF: xref Prev is not integer: %v", prevoff)
 		}
 		b := newBuffer(io.NewSectionReader(r.f, off, r.end-off), off)
-		obj1 := b.readObject()
+		obj1, err := b.readObject()
+		if err != nil {
+			return nil, objptr{}, nil, err
+		}
 		obj, ok := obj1.(objdef)
 		if !ok {
 			return nil, objptr{}, nil, fmt.Errorf("malformed PDF: xref prev stream not found: %v", objfmt(obj1))
@@ -353,7 +362,12 @@ func readXrefTable(r *Reader, b *buffer) ([]xref, objptr, dict, error) {
 		return nil, objptr{}, nil, fmt.Errorf("malformed PDF: %v", err)
 	}
 
-	trailer, ok := b.readObject().(dict)
+	res, err := b.readObject()
+	if err != nil {
+		return nil, objptr{}, nil, err
+	}
+
+	trailer, ok := res.(dict)
 	if !ok {
 		return nil, objptr{}, nil, fmt.Errorf("malformed PDF: xref table not followed by trailer dictionary")
 	}
@@ -373,7 +387,11 @@ func readXrefTable(r *Reader, b *buffer) ([]xref, objptr, dict, error) {
 			return nil, objptr{}, nil, fmt.Errorf("malformed PDF: %v", err)
 		}
 
-		trailer, ok := b.readObject().(dict)
+		res, err := b.readObject()
+		if err != nil {
+			return nil, objptr{}, nil, err
+		}
+		trailer, ok := res.(dict)
 		if !ok {
 			return nil, objptr{}, nil, fmt.Errorf("malformed PDF: xref Prev table not followed by trailer dictionary")
 		}
@@ -716,7 +734,7 @@ func (r *Reader) resolve(parent objptr, x interface{}) Value {
 		if xref.ptr != ptr || !xref.inStream && xref.offset == 0 {
 			return Value{}
 		}
-		var obj object
+		// var obj object
 		if xref.inStream {
 			strm := r.resolve(parent, xref.stream)
 		Search:
@@ -739,7 +757,10 @@ func (r *Reader) resolve(parent objptr, x interface{}) Value {
 					off, _ := b.readToken().(int64)
 					if uint32(id) == ptr.id {
 						b.seekForward(first + off)
-						x = b.readObject()
+						_, err := b.readObject()
+						if err != nil {
+							return Value{}
+						}
 						break Search
 					}
 				}
@@ -753,7 +774,10 @@ func (r *Reader) resolve(parent objptr, x interface{}) Value {
 			b := newBuffer(io.NewSectionReader(r.f, xref.offset, r.end-xref.offset), xref.offset)
 			b.key = r.key
 			b.useAES = r.useAES
-			obj = b.readObject()
+			obj, err := b.readObject()
+			if err != nil {
+				return Value{}
+			}
 			def, ok := obj.(objdef)
 			if !ok {
 				panic(fmt.Errorf("loading %v: found %T instead of objdef", ptr, obj))
@@ -773,7 +797,9 @@ func (r *Reader) resolve(parent objptr, x interface{}) Value {
 	case string:
 		return Value{r, parent, x}
 	default:
-		panic(fmt.Errorf("unexpected value type %T in resolve", x))
+		// panic(fmt.Errorf("unexpected value type %T in resolve", x))
+		fmt.Sprintf("unexpected value type %T in resolve", x)
+		return Value{}
 	}
 }