New Forum | Previous | Next | (P-PDF) Developers
Topic: Text under Image (Via Email)
Conf: (P-PDF) Developers, Msg: 68812
Date: 7/17/2002 06:13 PM
I'm trying to create PDF files that contains an image and some text
hidden under it(the text is read by OCR).
For me to have not to bother with Fonts i've decided that i will always
store text using Courier Font but i need to recreate spacing info.
- My image is 200 DPI B/W
- My sample text is 100 pixels wide
- Let's say it's a five character word
i've to put in my content stream a text token that creates a 30 pixel
wide hidden text the user can select.
I understand that Courier is 600 Glyph Units Wide so i think that
- I create a page of the same size of the image
- I set CTM to have the image cover the entire page
- I set Text Matrix to identity
- So a Device Unit is 2.77 pixels (Unit= ImageRes / PDFRes = 200 / 72 =
- So Courier Width is 1.66 pixels (Width= 600 * Unit / 1000 = 600 * 2.77
/ 1000 = 1.66)
- I set Font Size to 10
- So my new Width is 16.60 (Width = Width * FontSize= 1.66 * 10 = 16.60)
- So my five character string will be 83 pixels wide (Wide= N * Width =
5 * 16.60= 83)
So the difference between the real text width (100 pixel) and the "PDF
one"(83) is 17.
Then i use PDF spacing commands to generate this gap but when i open the
PDF for viewing i get a smaller token then i espect.
Where is it wrong?