image reading

[vimal3271]

I want to know how to read image files in C.. what are the headers
that i should include? is there any tutorials regarding this ? pls
inform me.

[Richard Heathfield]

vi*******@gmail .com said:

I want to know how to read image files in C.. what are the headers
that i should include?

C doesn't directly support any particular image format (although one might
make out a case for XPM), but it's easy enough to open a file using fopen.
Then comes the fun part - working out which bit of the file means what.

is there any tutorials regarding this ?

http://www.wotsit.org has the specs on lots of file formats.

--
Richard Heathfield <http://www.cpax.org.uk >
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999

[vippstar]

On Oct 6, 4:18 pm, vimal3...@gmail .com wrote:

I want to know how to read image files in C.. what are the headers
that i should include? is there any tutorials regarding this ?

You can open files with fopen. You can read their data with various
functions, for example, fgetc, fread.
The headers that should be included depend on the functions you are
going to use.
Any decent C book will help you with all these.
I recommend K&R2.

pls inform me.

pls? Don't you mean please? Type the whole word, please.

[Richard Tobin]

In article <5a************ *************** *******@c22g200 0prc.googlegrou ps.com>,
<vi*******@gmai l.comwrote:

>I want to know how to read image files in C.. what are the headers
that i should include? is there any tutorials regarding this ? pls
inform me.

You probably don't want to write this yourself. There are free
libraries available for the common formats like JPEG and TIFF, and
they should be fairly portable. Obviously displaying an image is
system-dependent, but just reading in the data is much less so.

Start by Googling for libjpeg, libtiff, libpng...

-- Richard
--
Please remember to mention me / in tapes you leave behind.

[viza]

On Mon, 06 Oct 2008 06:18:32 -0700, vimal3271 wrote:

I want to know how to read image files in C.. what are the headers that
i should include? is there any tutorials regarding this ? pls inform me.

Simple:

libgd http://www.libgd.org

Powerful:

libvips http://vips.sf.net

[Richard Heathfield]

vi******@gmail. com said:

On Oct 6, 4:18 pm, vimal3...@gmail .com wrote:

>I want to know how to read image files in C.. what are the headers
that i should include? is there any tutorials regarding this ?

You can open files with fopen. You can read their data with various
functions, for example, fgetc, fread.
The headers that should be included depend on the functions you are
going to use.
Any decent C book will help you with all these.
I recommend K&R2.

Perhaps you could remind me which section of K&R2 deals with image formats?

--
Richard Heathfield <http://www.cpax.org.uk >
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999

[vippstar]

On Oct 6, 6:20 pm, Richard Heathfield <[e-mail].i nvalidwrote:

vipps...@gmail. com said:

On Oct 6, 4:18 pm, vimal3...@gmail .com wrote:

I want to know how to read image files in C.. what are the headers
that i should include? is there any tutorials regarding this ?

You can open files with fopen. You can read their data with various
functions, for example, fgetc, fread.
The headers that should be included depend on the functions you are
going to use.
Any decent C book will help you with all these.
I recommend K&R2.

Perhaps you could remind me which section of K&R2 deals with image formats?

OP mentioned image files, image files are just files.

[adam majewski]

vi*******@gmail .com pisze:

I want to know how to read image files in C.. what are the headers
that i should include? is there any tutorials regarding this ? pls
inform me.

For me the simplest image file is PPM. If you can create file you can
also read it.

=============== ===
#include <stdio.h>
int main() {
const int dimx = 800;
const int dimy = 800;
int i, j;
FILE * fp = fopen("first.pp m", "wb"); /* b - tryb binarny */
fprintf(fp, "P6\n%d %d\n255\n", dimx, dimy);
for(j=0; j<dimy; ++j){
for(i=0; i<dimx; ++i){
static unsigned char color[3];
color[0]=i % 255; /* red */
color[1]=j % 255; /* green */
color[2]=(i*j) % 255; /* blue */
fwrite(color,1, 3,fp);
}
}
fclose(fp);
return 0;
}

=============== =============== ======
Look also :

http://fraktal.republika.pl/g_file.html
HTH

Adam

[Richard Heathfield]

vi******@gmail. com said:

On Oct 6, 6:20 pm, Richard Heathfield <[e-mail].i nvalidwrote:

>vipps...@gmail .com said:

On Oct 6, 4:18 pm, vimal3...@gmail .com wrote:
I want to know how to read image files in C.. what are the headers
that i should include? is there any tutorials regarding this ?

You can open files with fopen. You can read their data with various
functions, for example, fgetc, fread.
The headers that should be included depend on the functions you are
going to use.
Any decent C book will help you with all these.
I recommend K&R2.

Perhaps you could remind me which section of K&R2 deals with image
formats?

OP mentioned image files, image files are just files.

On one level, yes, that's true - but if he just meant arbitrary files, he'd
have said so. He specifically mentioned image files, and it doesn't
require a genius to deduce that he wishes to do some kind of image
processing (even if it's only display), which means he's going to need to
be able to decode image formats. He realises this. I realise this. And I
suspect you realise this too. To pretend otherwise is disingenuous.

--
Richard Heathfield <http://www.cpax.org.uk >
Email: -http://www. +rjh@
Google users: <http://www.cpax.org.uk/prg/writings/googly.php>
"Usenet is a strange place" - dmr 29 July 1999

[jellybean stonerfish]

On Mon, 06 Oct 2008 06:18:32 -0700, vimal3271 wrote:

I want to know how to read image files in C.. what are the headers that
i should include? is there any tutorials regarding this ? pls inform me.

Well, it depends on which formats you need to open. Do you just want to
read the image files, or be able to display them.

You could try "Developer' s Image Library" and write code to use it.

http://directory.fsf.org/project/DevIL/

Or for more open source image libraries, you could look here.

http://directory.fsf.org/category/ilibs/

stonerfish