Re: [GD-DEVEL] Color bug in JPEG output with 2.0.36

Hi Ethan!

On Sun, Mar 30, 2008 at 6:01 AM, Ethan A Merritt
<[email protected]> wrote:
> I am forwarding a bug report from a gnuplot user who
>  tried out the current gd 2.0.36RC:

Thanks for this report! If it persists after our tests, can you open
an issue in bugs.libgd.org please?

>  > I updated from 2.0.33 to the most recent test version, 2.0.36RC.  The JPEG
>  > test no longer segfaults.  However, the color of the sinusoid is brown
>  > instead of bright red as it is for the PNG output.
>
>  And indeed, I can confirm that the colors coming out of JPEG are
>  strange.  In particular, pure red is rendered as brown.

As far as I can see, we did not change the JPEG codec since 2.0.29
except a sanity check
(http://cvs.php.net/viewvc.cgi/gd/libgd/src/gd_jpeg.c). I can't
reproduce the problem (if I got it correctly) here (linux/windows, 32
or 64bit).

Can you try using the attached code (result image attached too)?

Also it would help to have the script to reproduce it (gnuplot, c, php or perl).

Cheers,
-- 
Pierre
http://blog.thepimp.net | http://www.libgd.org

/* $Id: copyrotated.c,v 1.2 2008/02/28 09:49:52 pajoye Exp $ */
#include "gd.h"
#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **arg)
{
	FILE *fp;
	gdImagePtr im;

	im = gdImageCreateTrueColor(100, 100);
	if (!im) {
		fprintf(stderr, "Can't create a new image");
		gdImageDestroy(im);
		return 1;
	}
	gdImageFilledRectangle(im, 0, 0, gdImageSX(im), gdImageSY(im), gdTrueColorAlpha(255, 255, 255, 0));
	gdImageFilledRectangle(im, 20, 20, gdImageSX(im) - 21, gdImageSY(im) - 21,  gdTrueColorAlpha(255, 0, 0, 0));


	fp = fopen("jpeg_out.jpeg", "wb");
	if (!fp) {
		fprintf(stderr, "Can't open jpeg file\n");
		gdImageDestroy(im);
		return 1;
	}

	gdImageJpeg(im, fp, 90);
	fclose(fp);

	gdImageDestroy(im);
	return 0;
}