Legacy ImageMagick Discussions Archive

BTW. That command will also involve recompressing the image which by default will use a quality of 75. You can use "-quality 95" to get a better quality image but you can't avoid the image degradation caused by decompressing and recompressing it so you should try to combine these operation...

If you want to force the JPG header to 72 dpi use: Pete

-delete is not for deleting files. It deletes an image or group of images from an image sequence such as you would get from (for example) an animated GIF.
See: http://magick.imagemagick.org/script/co ... php#delete

Pete

Try adding "fclose(stdout);" after your system call.

Pete

Yes, I usually install Q8.

Pete

I think that system() just passes all its arguments to identify without interpreting ">out.txt" as redirection. You have to do the redirection yourself. I don't know how you would do this in C++ but in C I did this with the freopen function: freopen("out.txt","w",stdout...

The MagickWand source code says that "80% is a good starting point" and this means 80% of QuantumRange. If 50000 is giving you a good result that would make sense if you are using a Q16 version of IM because 80% of the Q16 QuantumRange is 52428.

Pete

I installed IM 6.3.1 and now it produces the same image.
I also installed MatrixReal and got the perspective transform to work.

Pete

I've got Perl installed on my WinXP system but I can't get the matrix package to install. So I just cut your result: det=-0.003057*i + -0.000389*j + 1; xx=(0.533277*i + -0.033042*j + 5.690943)/det; yy=(-0.392491*i + 0.833446*j + 15.611041)/det; and pasted it into the appropriate place in the convert...

Anthony: I tried out your transformation example but didn't get quite the same result as you did:
http://members.shaw.ca/el_supremo/build ... formed.png

I'm using 6.3.0 Q8. Would the Q8 version make a difference to the result?

Pete

It depends what you mean by the "correct" dpi
IM gets the dpi info from the jpg header. Photoshop (and GIMP?) gets the info from the EXIF header which is also in the file.

Pete

[edit]Oooops. I meant to reply to your post in the MagickWand forum. Oh well. I think this does what you wanted :-) I'd be interested if anyone has a better/alternate method. Pete MagickWand *magick_wand = NULL,*region_wand = NULL; int dx,dy,x,y; MagickWandGenesis(); magick_wand = NewMagickWand(); M...

I saw your other post and tried it too. Haven't solved it yet but will probably post what I have.

Seafood? YUMMY

Pete

I have a C function, which uses MagickWand to produce a plain transparent PNG. This should give you the essence of what is required for a PHP script. Pete /* Make a plain transparent image */ #include <windows.h> #include <wand/magick_wand.h> void test_wand(void) { MagickWand *magick_wand = NULL; Pi...

After PixelSetColor add a PixelSetOpacity - I think it will look like this:
PixelSetOpacity($pixel,"0.8");
for almost transparent text.

Pete