I want write long text in pdf. Does exist any way to split it to lines automaticly using only pdf specification?
6 0 obj
<< /Length 999 >>
stream
BT
/F1 24 Tf
100 520 Td
(loooooong looooo...ooong text) Tj
ET
endstream
endobj
As result text goes out of right border of page. I can split text by ', but it means I will have to calculate length of every word and split text, when sum of lengths reach some number.
6 0 obj
<< /Length 999 >>
stream
BT
/F1 24 Tf
30 TL
100 520 Td
(loooooong looooo...ooong text) Tj
(loooooong looooo...ooong text) '
(loooooong looooo...ooong text) '
ET
endstream
endobj
I want something like:
6 0 obj
<< /Length 999 >>
stream
BT
/F1 24 Tf
100 520 Td
YYY XX
(loooooong looooo...ooong text) Tj
ET
endstream
endobj
where YYY is length of line and XX some operator.
No.
Short answer, but that's because it's not possible. PDF allows you to very accurately specify where each character needs to go, but it can't automatically do line-splitting for you. That's always your responsibility.
Related
I have to write a multi lingual text a pdf using C++. I have unicode values as well as glyph id values with their advances and displacements for the string input.
But I need to know how to position the dependent glyph with the independent base glyph.
Suppose if I have a advance and displacement values using FreeType / HarfBuzz, how should I input these values into the pdf content stream along with the glyph ids in the input.
I have tried the output values of FreeType & HarfBuzz, which could print the individual glyphs properly, but the positioning of the glyphs with its base glyph is not proper still, even if i used the advance and displacement values given in their outputs.
I just need the logic of how to use the output values in the content stream to deliver a proper readable word/letter.
Example:
Text = tamil letter + hindi letter.
I need to print this output.proper output
But currently only I am able to print this. improper output
Tamil combined letter:
வ = U+0BB5 TAMIL LETTER VA = base glyph
ா = U+0BBE TAMIL VOWEL SIGN AA = dependent glyph
HarfBuzz run:
hb-shape.exe -O json -u u+0bb5,u+0bbe --no-glyph-names "C:\\Windows\\Fonts\\Nirmala.ttf"
gid output:
[{"g":2953,"cl":0,"dx":0,"dy":0,"ax":2111,"ay":0},{"g":2959,"cl":0,"dx":0,"dy":0,"ax":1453,"ay":0}]
Hindi combined letter:
म = U+092E DEVANAGARI LETTER MA = base glyph
ि = U+093F DEVANAGARI VOWEL SIGN I = dependent glyph
HarfBuzz run:
hb-shape.exe -O json -u u+092e,u+093f --no-glyph-names "C:\\Windows\\Fonts\\Nirmala.ttf"
gid output:
[{"g":302,"cl":0,"dx":0,"dy":0,"ax":532,"ay":0},{"g":273,"cl":0,"dx":0,"dy":0,"ax":1379,"ay":0}]
Subjecting these output values into the formula,
PDF doc formula
Assuming unity for all variables except width and advance,
by obtaining the width value using FreeType and computing them.
Glyph Advance values for four glyphs in order:
tx = 1769
tx = 1132
tx = 1586
tx = 1448
If I provide these values in the content stream in the order as
<glyph id 1> tx 1 <glyph id 2> tx 2 <glyph id 3> tx 3 <glyph id 4> tx 4
Content stream:
/OC /oc2 BDC q BT /FXF1 1 Tf 70.866142 0.000000 0.000000 70.866142 28.346457 141.732285 Tm[<0B89>-1769<0B8F>-1132<0111>-1586<012E>-1448]TJ ET Q EMC
PDF Doc says (+)ve value of advances will move the text towards left.
Is it other way...?
Or if the difference of the advances is to be obtained...?
Additional PDF objects:
Font descriptor object,Base font object,Font object.
I have tried using only advance values and only computed values also.
The only problem is the horizontal & vertical space within combined glyphs, which also affects the spacing between subsequent glyphs.
Any of these does not render the glyphs as legible, atleast in a generalised programmatic manner.
From my analysis of #mkl at various stack overflow places, I suspect the need for individual transformation matrix or Td for each glyph. But is it that complex...?
As per my thought, it must be easily be rendered.
If individual transformation matrix or Td is the need, then how to compute the values to be supplied in for them.
Any help & guidance is welcome and much appreciated.
Thank you.
It helps to work out pdf as plain text you can compile by save in notepad.
Here I am altering a batch.cmd (work in progress :-) to test my compiler handles the changes as text but you can use raw pdf in editor too. beware cut and paste may need a value or two changed Also unknown yet how you can easily reference non Latin fonts (next hurdle after images, which are almost done), so I used "symbol" font as illustrative of those positioning mods.
Note for specific queries #mkl is the expert I simply do programming by examples, that function not by the book.
%PDF-1.0
%µ¶µ¶
1 0 obj<</Type/Catalog/Pages 2 0 R>>endobj
2 0 obj<</Type/Pages/Count 1/Kids[3 0 R]>>endobj
3 0 obj<</Type/Page/Parent 2 0 R/MediaBox [0 0 594 792]/Resources<</Font<< /F1 4 0 R /F2 5 0 R>>>>/Contents 6 0 R>>endobj
4 0 obj<</Type/Font/Subtype/Type1/BaseFont/Helvetica>>endobj
5 0 obj<</Type/Font/Subtype/Type1/BaseFont/Symbol>>endobj
%Comment the following /Length 0999 is a dummy value it should be altered to equal decimal stream length, but most readers will ignore or work around invalid
6 0 obj<</Length 1326>>
stream
q
BT /F1 20 Tf 072 740 Td (20 units (default units usually = pts) high Headline) Tj ET
BT /F1 16 Tf 036 700 Td (All text is "Body" text. (no heads or tails)) Tj ET
BT /F1 10 Tf 004 780 Td (Text can be any order see "Body" text above. (Printed by Filename="C:\Users\K\Downloads\Programming\CMDaPDF\MAKE2PDF.cmd") spot the escape errors) Tj ET
BT /F1 12 Tf 036 675 Td (Here # 12 units high you must include just enough text for parts of a line. PDF has no page feeds no wrapping,) Tj 0 -20 Td (nor \\new line feed, no ¶aragraphs) Tj 86 -15 Td (nor carriage \r\\return. \n\r ) Tj 100 5 Td ( It is not \007\010\011\012\\tabular, each page is one row of multiple pages,) Tj 50 -15 Td (each page is one text column wide .[ ×] no yes check) Tj 0 -10 Td (each row is one text column wide .[x] no is yes) Tj 0 -10 Td (each row is one text column wide . · bullet point OK) Tj ET
BT +0.50 Tc -1.4 Tw 999 TL /F1 1 Tf 15 001 10. 30 200.000 440.000 Tm [(Jane A)600(usten)] TJ ET
BT +0.50 Tc 0.00 Tw 000 TL /F2 1 Tf 15 000 000 15 200.000 430.000 Tm [(Ja)-1000(ne Austen)] TJ ET
BT -1.20 Tc 0.00 Tw 999 TL /F2 1 Tf 15 000 000 15 200.000 420.000 Tm [(J)-1200(a)800(ne Austen)] TJ ET
BT +0.00 Tc 0.00 Tw 000 TL /F2 1 Tf 15 000 000 15 200.000 410.000 Tm [(Jane A)100(us)-500(ten)] TJ ET
Q
endstream
xref
0 7
0000000000 65535 f
0000000019 00000 n
0000000065 00000 n
0000000117 00000 n
0000000242 00000 n
0000000306 00000 n
0000000527 00000 n
trailer<</Size 7/Root 1 0 R>>
startxref
1903
%%EOF
I have this s variable string:
ID#9NAME#9VALUE
How this string look like in PDF?
(ID) Tj (NAME) Tj (VALUE) Tj
I have to convert the s variable to PDF string.
How can I change the #9 character to a working tabstop character?
I can change the #9 character to 7 pieces of #20, but it is not good for me, because I and W are different widths.
Is there a trick?
Like horizontal spacing in percent?
(ID) Tj
some code that spacing 100 horizontal pixels
(NAME) Tj
some code that spacing 100 horizontal pixels
(VALUE) Tj
Your #9 seems to be ^09 i.e. (HT)
That should be x09 in (Base 16 / hex.) or \011 (base 8) or \t in literal string
IF defined like that in a base font, then you should be able to insert that.
(ID\t\tNAME\t\tVALUE) TJ
or
(ID\011\011NAME\011\011VALUE) Tj
However as pointed out by #mkl those were traditional mechanical printer carriage stops that could be set ON at 4 or 8 characters from line left or anything the printer operator chose to place indents or columns. Thus in a Word Processor are highly variable in number and position. But in a PDF are usually ignored.
In PDF it is more conventional to set each block of characters at a new x,y position, where y is constant for each text block at that elevation.
So for a tab stop approach with tabs at one inch (based on default 1 unit =1/72") try this
stream
q
BT
/F1 12 Tf
1 0 0 1 144 720 Tm
(ID) Tj
ET
BT
/F1 12 Tf
1 0 0 1 216 720 Tm
(NAME) Tj
ET
BT
/F1 12 Tf
1 0 0 1 288 720 Tm
(VALUE) Tj
ET
Q
endstream
Remember in PDF all whitespace is equal, but some is more so than others.
so here find id name value accepts the non existent tabs as a single white space:-
Finally to answer your query you can set fixed space from the start of a text to the start of another just like tab stops using Td. Note I had intentionally used TD and Td mixed to show it does not matter in such cases :-), however the Human readable convention is to use CAPS for the Object (Noun) and lowercase the "action" (Verb) so Td is better for debugging by eye.
This can be written as suggested by #mkl (with me adding a start point)
50 800 Td (ID) Tj 100 0 Td (NAME) Tj 100 0 Td (VALUE) Tj
In comments you asked about adding lines and the simplest, for line by line loop programming, is to use something like this. (In this case skipping 780) and contra my above comment BT and ET are usually both CAPS.
BT 50 800 Td (ID) Tj 100 0 Td (NAME) Tj 100 0 Td (VALUE) Tj ET
BT 50 760 Td (A1) Tj 100 0 Td (Example) Tj 100 0 Td (2000) Tj ET
BT 50 740 Td (B2) Tj 100 0 Td (Another) Tj 100 0 Td (1000) Tj ET
I'm trying to manually create a PDF document (using the PDFGen C code on github). This is on a small footprint device with limited storage.
All works fine until I want to embed (say) the Unicode Ohms character (U+2126).
Below is the test file I'm using, which should show "Hello" with an Ohms symbol after the 'H'.
However, it actually shows "H!&ello".
%PDF-1.4
<hex chars removed>
1 0 obj
<< /Pages 2 0 R /Type /Catalog >>
endobj
2 0 obj
<< /Count 1 /Kids [ 3 0 R ] /Type /Pages >>
endobj
3 0 obj
<< /Contents 4 0 R /MediaBox [ 0 0 500 800 ] /Parent 2 0 R /Resources 5 0 R /Type /Page >>
endobj
4 0 obj
<< /Length 57 >>
stream
BT /F1 24 Tf 175 720 Td <FEFF004821260065006C006C006F> Tj ET
endstream
endobj
5 0 obj
<< /Font << /F1 6 0 R >> >>
endobj
6 0 obj
<< /BaseFont /Courier /Subtype /Type1 /Type /Font >>
endobj
xref
0 7
0000000000 65535 f
0000000015 00000 n
0000000064 00000 n
0000000123 00000 n
0000000229 00000 n
0000000335 00000 n
0000000378 00000 n
trailer << /Root 1 0 R /Size 7 /ID [<89311a609a751f1666063e6962e79bd5><89311a609a751f1666063e6962e79bd5>] >>
startxref
448
%%EOF
I can only assume my Unicode hex string <FEFF004821260065006C006C006F> is badly formatted.
Or is the Font definition incorrect ?
Or is my understanding of how to embed Unicode wrong ?
I'm ultimately not wanting to embed any fonts as I don't have the storage space or processing power. I just want to add Unicode characters and rely on the PDF renderer to work out how to display them using the default Courier font.
Is that even possible ?
Thanks in advance for any help/advice/comments.
UPDATE
After some useful advice below, I've now managed to achieve what I needed.
I modded my code to switch fonts on a per-character basis between Courier and Symbol and now support (nearly) all the standard characters.
I also added some character scaling to keep the Symbol characters aligned with the Courier font but the end result works for me :)
Here's an image of my test PDF ...
Oddly the original PC IBM 437 code set included Ω wiki note i [03A9] (234) but did not make it to Courier ??
You could try coding those few characters you need as an embedded sub-setted symbol font and quite possibly do that using ascii(7bit) or ansi(8bit) but the overheads would be tremendous for your few characters.
Simpler try switching fonts (as required per target characters) to Symbol font and it could look like this
P.S. the codes dont need to be "word" doubles there are only 256 chars.
<< /BaseFont /Symbol /Subtype /Type1 /Type /Font >>
BT /F2 24 Tf 175 720 Td <4857657C7C6F20766FC27C64> Tj ET
By alternating courier and symbol you will get your desired
In your code it could look something like (with included transforms)
BT
/F0 24 Tf 1 0 0 1 0 .0675 Tm (H) Tj
ET
BT
/F1 24 Tf 1 0 0 1 14.4 .0675 Tm <003a> Tj
ET
BT
/F0 24 Tf 1 0 0 1 32.832 .0675 Tm (ello) Tj
ET
Note my editor used F0 for Courier and F1 for Symbol (base 0 is more normal)
Also it used a slightly different code method of defining Omega as <003a>
Here I am tweaking the text in Windows Notepad to watch how compiling (Ctrl+S) moves the Omega character spacing whilst watching it slide sideways live in the Previewer. Also note that Upper case Omega is W in the raw symbol font !!
So my replacement fix for your code looks like this (You can easily make it look closer to yours, and leaner, by removing white space and line feeds)
%PDF-1.4
%µ¶
1 0 obj
<<
/Pages 2 0 R
/Type /Catalog
>>
endobj
2 0 obj
<<
/Count 1
/Kids [ 3 0 R ]
/Type /Pages
>>
endobj
3 0 obj
<<
/Contents 4 0 R
/MediaBox [ 0 0 500 800 ]
/Parent 2 0 R
/Resources <<
/Font <<
/F1 5 0 R
/F2 6 0 R
>>
>>
/Type /Page
>>
endobj
4 0 obj
<<
/Length 133
>>
stream
q
BT
/F1 24 Tf
1 0 0 1 175 720 Tm
(H) Tj
ET
BT
/F2 24 Tf
1 0 0 1 189 720 Tm
(W) Tj
ET
BT
/F1 24 Tf
1 0 0 1 206 720 Tm
(ello) Tj
ET
Q
endstream
endobj
5 0 obj
<<
/BaseFont /Courier
/Subtype /Type1
/Type /Font
>>
endobj
6 0 obj
<<
/BaseFont /Symbol
/Subtype /Type1
/Type /Font
>>
endobj
xref
0 7
0000000000 65536 f
0000000016 00000 n
0000000070 00000 n
0000000136 00000 n
0000000307 00000 n
0000000494 00000 n
0000000569 00000 n
trailer
<<
/Size 7
/Root 1 0 R
/ID [ <89311A609A751F1666063E6962E79BD5> <EE408A115072E92E3A34C8BB8BDC6AE6> ]
>>
startxref
643
%%EOF
You cannot do it.
Note: you want to insert a Unicode character (not a UTF-16, which it is just one of many representation/encoding of Unicode).
No fonts includes all glyphs, and as far I know, only few Latin-1 fonts are safe (and required) for PDF. Note: such fonts requires a Latin-1 encoding (contrary of all other fonts, this is just a portability issue, for "pre Unicode epoch"). An additional problem. Type1 uses glyph indices, which may not be the same as Unicode Codepoints (in fact, I think they are always different). IIRC Adobe has some documentation about this. And type1 is nearly out of support, maybe it is better not to use it for 2021 programs.
You may assume people will have Microsoft Windows, and so you can use Symbol font (and using Omega, instead of Ohm, which may be represented with the same glyph). But in this case you are creating a "Non-Portable" Portable Document format (PDF).
I am trying to learn structure of a pdf document from guide. I could add the text and shapes with lines, but I am having problem displaying the image.
The code I am writing to display an image is (on page 54):
%PDF-1.2
% based on e08.pdf
1 0 obj
<<
/Type /Page
/Parent 5 0 R
/Resources 3 0 R
/Contents 2 0 R
>>
endobj
2 0 obj
<< /Length 51 >>
stream
BT
/F1 24 Tf
1 0 0 1 260 254 Tm
/CS1 cs
63 127 127 sc
(Hello World)Tj
ET
100 0 127 sc
/CS2 CS
0 0 1 SC
315 226 m
299 182 l
339 208 l
291 208 l
331 182 l
b
100 0 0 100 65 326 cm
BI /W 36 /H 32 /BPC 8
/CS /DeviceGray
ID
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EI
endstream
endobj
3 0 obj
<<
/ProcSet[/PDF/Text]
/Font <</F1 4 0 R>>
/ColorSpace
<<
/CS1
[
/Lab
<<
/Range [-128 127 -128 127]
/WhitePoint [ 0.951 1 1.089]
>>
]
/CS2
[
/CalRGB
<<
/Gamma [2.222 2.222 2.222]
/Matrix
[
0.412 0.213 0.019
0.358 0.715 0.119
0.181 0.072 0.951
]
/WhitePoint [0.951 1 1.089]
>>
]
>>
>>
endobj
4 0 obj
<<
/Type /Font
/Subtype /Type1
/Name /F1
/BaseFont/Helvetica
>>
endobj
5 0 obj
<<
/Type /Pages
/Kids [ 1 0 R ]
/Count 1
/MediaBox [ 0 0 612 446 ]
>>
endobj
6 0 obj
<<
/Type /Catalog
/Pages 5 0 R
>>
endobj
trailer
<< /Root 6 0 R >>
What I expect from it is:
But when I open the file in Acrobat Reader DC 2015, I see the text and the star, but not the image logo.
Note:
I have formatted the code myself, so please let me know if it is not proper.
I assume that there are problems with the characters that are used to show the Adobe logo. I guess the characters should be binary data, and when the PDF is generated, they are converted to those symbols.
Here the author is using pdf 1.2, that is pretty old, but as far as I know it should not make a problem, since pdf is backward compatible.
My question:
Why I cannot see the desired result as shown in the image using this code?
How to get the codes needed to use in PDF to display an image. Let us say this textual representation of the binary code (or even the binary itself) that I have used in my code?
Update:
As mentioned in the comment, cross reference table does not exist in my code, but when I generated that with pdftk tool, the result was the same.
The major problem with your inline image is that you try to create a binary data block using text.
The data between ID and EI is interpreted as a stream of a single (!) white space character followed by height x width x bits-per-component/8 x number-of-components data bytes, i.e. in your case (according to /W 36 /H 32 /BPC 8 /CS /DeviceGray) 32 * 36 * 8/8 * 1 bytes.
This is not the case in your sample. In your question you have that data block indented which adds numerous bytes to the stream. Furthermore you have lines containing different numbers of bytes (even though they may look equally long in an editor).
Your binary download differs substantially from your question text, e.g. instead of the ˇ characters filling the A you have . characters there. If suffers from unequal line lengths, too
I assume you use a text editor to write that PDF which is a bad choice because you do not correctly see the real number of bytes used. Especially problematic are control characters and byte values not associated with a character in your encoding.
Let's therefore try something more simple and only use characters in the ASCII range and a smaller, simpler form:
Depending on your end-of-line sequence (their bytes are part of the data bytes!!) use either of the following two samples
in case of single byte end-of-line sequences (only CR or only LF, typical for Mac or Unix):
BI /W 5 /H 4 /BPC 8
/CS /DeviceGray
ID
zzzz
z..z
z..z
zzzz
EI
in case of two byte end-of-line sequences (CR LF, typical for DOS / MS Windows):
BI /W 6 /H 4 /BPC 8
/CS /DeviceGray
ID
zzzz
z..z
z..z
zzzz
EI
Do take care not to add any leading or trailing spaces! They would also be interpreted as data bytes!
The result looks like this in the first case
and this in the second case
The dark bar(s) on the right / on both right and left is/are due to the line ending character(s).
If you don't want such bars, you have to get rid of the line endings, e.g.
BI /W 4 /H 4 /BPC 8
/CS /DeviceGray
ID zzzzz..zz..zzzzz EI
resulting in
That all been said, please do yourself a favor and
don't create PDFs as text, e.g. in a text editor! While they can be understood to a certain degree in a text viewer, creating them in a text editor very soon becomes hell;
don't use inline images but instead image resources! Inline images have proved to be troublesome and in PDF 2.0 will be deprecated or at least restricted to very small sizes; and finally
don't use the PDF 1.2 reference but instead the current PDF standard ISO 32000-1! Adobe personal called the old PDF references not normative in nature, so you can not count on what they say.
I have a source pdf which I am modifying by adding text objects. I am using "Incremental Updates" which is mentioned in the PDF specification. But while adding text objects using this method I am making some mistakes due to which the pdf doesn't render properly in Adobe Reader 11. When the pdf is opened and I double-click on it, the added text objects get deleted. I figured out that this is due to text annotation.
Now I want to know how a new text object can be added using incremental update? How do the Contents and RC of a free text annotation have to be to maintained?
Also is it possible to disable or delete the annotation so that my problem can be avoided easily? Because I want a simple pdf, I don't want annotation options.
The source pdf I am using is here.
The modified pdf after adding text object is here.
I am not sure that source pdf is itself proper according to pdf specification.
First off let me show you how easy things are if you can use a decent PDF library. I use iTextSharp as an example but the same can also be done with others like PDFBox or PDFNet (already mentioned by #Ika in his answer):
PdfReader reader = new PdfReader(sourcePdf);
using (PdfStamper stamper = new PdfStamper(reader, targetPdfStream)) {
Font FONT = new Font(Font.FontFamily.HELVETICA, 12, Font.BOLD, new GrayColor(0.75f));
PdfContentByte canvas = stamper.GetOverContent(1);
ColumnText.ShowTextAligned(
canvas,
Element.ALIGN_LEFT,
new Phrase("Hello people!", FONT),
36, 540, 0
);
}
(Derived from the Webified iTextSharp Example StampText.cs explained in chapter 6 of iText in Action — 2nd Edition.)
(Which PDF library you choose, depends on your general requirements and available license models.)
If, in spite of the ease of use of such PDF libraries, you insist on doing it manually, here some remarks:
First you have to find the Page dictionary of the page you want to add content to. Depending on the type of PDF this already might require decompression of object streams etc. but in your sample modified1.pdf that is not necessary:
7 0 obj
<</Rotate 90
/Type /Page
/TrimBox [ 9.54 6.12 585.68 835.88 ]
/Resources 8 0 R
/CropBox [ 0 0 595.22 842 ]
/ArtBox [ 9.54 18.36 585.68 842 ]
/Contents [ 9 0 R 10 0 R 11 0 R 12 0 R 13 0 R 14 0 R 15 0 R 16 0 R ]
/Parent 6 0 R
/MediaBox [ 0 0 595.22 842 ]
/Annots 17 0 R
/BleedBox [ 9.54 6.12 585.68 835.88 ]
>>
endobj
You see the array of references to content streams. This is where you have to add new page content to. You can manipulate an existing stream or create a new stream and add it to that array.
(Most PDFs have their content stream compressed. For the general case, therefore, you'd have to decompress a stream before you can work on it. Thus, in my eyes, the easier way would be to start a new stream.)
You chose to manipulate the last referenced stream 16 0 which in your PDF is uncompressed:
16 0 obj
<</Length 37 0 R>>
stream
S 1 0 0 1 13.183 0 cm 0 0 m
[...]
0 10 -10 -0 506.238 342.629 Tm
.13333 .11765 .12157 scn
-.0002 Tc
.0006 Tw
(the Bank and branch on which cheque is drawn\).)Tj
/F1 2 Tf
-15.1279 10.9462 Td
(abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789~!##$%^&*aaaaaaaaaaaaa)Tj
/F2 1 Tf
015.1279 01.9462 Td
(ANAabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789)Tj
ET
endstream
endobj
Your additions, I gather, are the two 3-liners at the bottom which first select a font, then position the insertion point and finally print a selection of letters.
Now you say you added text abc..z and ABC...Z just for testing. But letters b j k q v etc not appearing in the pdf. The problem becomes even more visible for your second addition of letters; here only the capital 'A' and 'N' are displayed.
This is due to the fact that the fonts in question are embedded into the PDF --- fonts are embedded into PDFs to allow PDF viewers on systems which don't have the font in question, to display the PDF --- but they are not completely embedded, only the subset of characters required from that font.
Let's look for the font F2 for which only 'N' and 'A' appear:
According to the page object, the page resources can be found in object 8 0:
8 0 obj
<</Font <</F1 45 0 R /TT2 46 0 R /F2 47 0 R>>
/ExtGState <</GS2 48 0 R>>
/ProcSet [ /PDF /Text ]
/ColorSpace <</Cs6 49 0 R>>
>>
endobj
So F2 is defined in 47 0:
47 0 obj
<</Subtype /Type1
/Type /Font
/Widths [ 722 250 250 250 250 250 250 250 250 250 250 250 250 722 ]
/Encoding 52 0 R
/FirstChar 65
/FontDescriptor 53 0 R
/ToUnicode 54 0 R
/BaseFont /ILBPOB+TimesNewRomanPSMT-Bold
/LastChar 78
>>
endobj
In the referenced ToUnicode map 54 0 you see
54 0 obj
<</Length 55 0 R>>stream
/CIDInit /ProcSet findresource begin 12 dict begin begincmap /CIDSystemInfo <<
/Registry (AAAAAA+F2+0) /Ordering (T1UV) /Supplement 0 >> def
/CMapName /AAAAAA+F2+0 def
/CMapType 2 def
1 begincodespacerange <41> <4e> endcodespacerange
2 beginbfchar
<41> <0041>
<4e> <004E>
endbfchar
endcmap CMapName currentdict /CMap defineresource pop end end
endstream
endobj
In this mapping you see that only character codes 0x41 'A' and 0x4e 'N' are mapped
In your document the font is used only to print "NA" in the amount table cells and for nothing else. Thus, only those two letters 'N' and 'A' are embedded, which results in your addition with that font only outputting these letters.
Thus, to successfully add text to the page you either have to check the font ressources associated with the page for the glyphs they provide (and restrict your additions to those glyphs) or you have to add your own font resource.
As the presence of characters in the encoding often is not as easy to see as it is here (ToUnicode is optional), I would propose, you add your own font ressources. The PDF specification ISO 32000-1 explains how to do that.
Furthermore you state the x and y axis position for the text is not properly displaying in pdf. While you don't say what exactly you mean, you should be aware that in the content stream you can apply affine transformations to the coordinate system of the page, i.e. stretch, skew, rotate, and move the axis.
If you want to use the original coordinate system and not depend on the coordinates to be proper at your additions, you should add an initial content stream to the page containing a q operator (to save the current graphics state on the graphics state stack) and start your additions in a new final content stream with a Q operator (to restore the graphics state by removing the most recently saved state from the stack and making it the current state).
EDIT As a sample I applied the Java equivalent of the C# code at the top to your modified1.pdf with append mode activated. The following objects were changed or added as a result:
The page object 7 0 has been updated:
7 0 obj
<</CropBox[0 0 595.22 842]
/Parent 6 0 R
/Contents[69 0 R 9 0 R 10 0 R 11 0 R 12 0 R 13 0 R 14 0 R 15 0 R 16 0 R 70 0 R]
/Type/Page
/Resources<<
/ExtGState<</GS2 48 0 R>>
/ProcSet [/PDF /Text /ImageB /ImageC /ImageI]
/ColorSpace<</Cs6 49 0 R>>
/Font<</F1 45 0 R/F2 47 0 R/TT2 46 0 R/Xi0 68 0 R>>
>>
/MediaBox[0 0 595.22 842]
/TrimBox[9.54 6.12 585.68 835.88]
/BleedBox[9.54 6.12 585.68 835.88]
/Annots 17 0 R
/ArtBox[9.54 18.36 585.68 842]
/Rotate 90
>>
endobj
If you compare with your former version, you see that
two new content streams have been added, 69 0 at the start and 70 0 at the end;
the resources are not an indirect object anymore but instead are directly included here;
the resources contain a new Font ressource Xi0 at 68 0.
Now let's look at the added objects.
This is the font ressource for Helvetica-Bold named Xi0 at 68 0:
68 0 obj
<</BaseFont/Helvetica-Bold
/Type/Font
/Encoding/WinAnsiEncoding
/Subtype/Type1
>>
endobj
Non-embedded, standard 14 font resources are not complicated at all...
Now there are the additional content streams. iText does compress them, but I'll show them in an uncompressed state here:
69 0 obj
<</Length 1>>stream
q
endstream
endobj
70 0 obj
<</Length 106>>stream
Q
q
0 1 -1 0 595.22 0 cm
q
BT
1 0 0 1 36 540 Tm
/Xi0 12 Tf
0.75 g
(Hello people!)Tj
0 g
ET
Q
Q
endstream
endobj
So the new content stream at the start stores the current graphic state, and the new one at the end retrieves that stored state, changes the coordinate system, positions for text insertion, selects font, font size, and the fill colour, and finally prints a string.