text digitization

[jimgardener]

i am trying to digitize a text file into tiff image.the algorithm is
as follows,
There is a 8x16, 256 character font table with 16 columns and 256
rows .each row of table represents a character(like 0...32,A,a etc)
and each column represents a row of font (font is of height
16).elements of the table are like 0x00,0x7e,0x81,0xff etc.Finding the
dot pattern for any character is done by using the value of a
character as one index into the font array, with the font row being
the other index.
i want to get a line of text from the file and using a for loop of 16
times (fontheight is 16) each character is examined and values are
taken from the font table
if textline is a line of text (probably obtained by readLine() of
BufferedReader)
int imageoffset=0;
for (int row=0 ; row<FONTHEIGHT ; row++){

for(int i=0;i<lengthof_textline;i++){
if(textline>SPACE){
bitimage[imageoffset++]=fonts[textline][row] ;
}
}
bit_image[imageoffset++]=EOLFLAG ;

}


here some constants are used to denote EOLFLAG ,SPACE etc
EOLFLAG =0x01 (hoping it will not occur for any in font data)
SPACE =0x20

the idea is to build bit_image with these hexadecimal values and
finally use this array to write an image(Tiff).There are some points
i would like to know
1.should i use a char array to represent bit_image? i believe that the
font table's array should be char[16][256] .
2.if bit_image is a char array filled with these font codes,can any
api translate it to a tiff image?I couldn't work out how to do this
using JAI.if anyone can ,pls help
jim

 

[Roedy Green]

i am trying to digitize a text file into tiff image.the algorithm is
as follows,

see http://mindprod.com/project/screencapture.html

 

[jimgardener]

own font data and maps that into an explicit two-dimensional array based
on the text input?

yes, i need to use a given font data array .
in c ,this could be done using char data type for each value like
0x81,0xff...i was not sure how to proceed in java.i guess i will have
to use char and not byte because byte b=0x81 will cause type
mismatch..
if i build a array of chars containing these font values ,then i need
a way to use that as image data of tiff..this is something i (with my
limited exp)couldn't find in JAI..

 

[Neil Coffey]

i am trying to digitize a text file into tiff image.the algorithm is
as follows,
There is a 8x16, 256 character font table with 16 columns and 256
rows .each row of table represents a character(like 0...32,A,a etc)
and each column represents a row of font (font is of height
16).elements of the table are like 0x00,0x7e,0x81,0xff etc.Finding the
dot pattern for any character is done by using the value of a
character as one index into the font array, with the font row being
the other index.

It sounds to me like you're trying to program Java like you'd
program a ZX Spectrum. The great thing about modern programming
languages is that they provide libraries for things like image
manipulation without you having to poke about with raw bytes and
ints...

Why not:
- for each character in the font table, create a BufferedImage for
that character, reading from the table and calling setRGB() to
set each pixel of the character as appropriate
- create a BufferedImage to hold your final image, then for each
character you need to place on it, call drawImage(), with one
of the font

2.if bit_image is a char array filled with these font codes,can any
api translate it to a tiff image?I couldn't work out how to do this
using JAI.if anyone can ,pls help

Yes, JAI allows you to save an image as a TIFF file. But you go from
an image object, not from a raw primitive array.

Neil

 

[Mark Space]

As far as actually generating the TIFF file goes, if you can install JAI
on your computer (or whatever computer will be running your code), then
you should be able to just use the link Logan provided. If not, the

Just to emphasize this point:

<http://java.sun.com/products/java-media/jai/iio.html>