Multipage TIFF file not having original TIFF image quality.

[rajendram]

Hi,

I have following code which generates multipage TIFF file name as multi.TIFF from the img folder. However it is failed to keep original individual TIFF image quality.
Please have a look into this issue and provide valid solution/feedback on this.

Code: Select all

$multiTIFF = new Imagick(); 
$mytifspath = "z:/imagemagik/img/";

foreach(new DirectoryIterator('z:/imagemagik/img/') as $file) 
{
    if( $file->isFile() === TRUE && $file->getBasename() !== 'Thumbs.db') 
	{ 
		$auxIMG = new Imagick(); 
		$auxIMG->ReadImage($mytifspath.htmlentities($file->getBasename())); 	
		$multiTIFF->addImage($auxIMG);		
       }
}
 $multiTIFF->writeImages('z:/imagemagik/multi.TIFF', true); 

Feedback appreciated..!

Thanks,
Rajendra

[snibgo]

What IM version? What platform?

What quality loss do you see? Can you put up sample images?

What compression are you using, if any? If they are JPEG-compressed, then IM will read each image and re-write it, which will lose quality. Zip or Lzw are better (lossless compression).

[rajendram]

Hi,

Thank you for your quick reply.
However I am here unable to attach file as I tried to PM also but it is not allowing to upload tiff/zip file.

I am using latest windows version of Imagemagick version ImageMagick 6.8.6-8 2013-08-04 Q16 under XAMPP 3.2.1 under Windows 7.


Thanks,
Rajendra

[snibgo]

You can put files on Dropbox.com or other free hosting site, and post the URL here.

[rajendram]

Hi,

Please check this zip file http://tinyurl.com/lmwq838 .

It consist of original grey colored file name as GreyColoredFile.TIFF.
And generated multipage tiff file as multi.TIFF which is created after merging 3 TIFF files including GreyColoredFile.TIFF file.

Thanks

[snibgo]

Your input file is greyscale, JPEG compressed. Your output is bilevel, Group4 compressed, probably because the first file was like that.

You should ensure that all input files to your convert are greyscale (not bilevel), and use "-compress Zip".

[rajendram]

Hi,

Please check this file http://tinyurl.com/o6e7hh3.
It is generated through dotnet tool.

Can such type of multipage TIFF image can be achieved?

Also do you expect me to change the compression of created individual tiff files to keep original image quality in generated multi.TIFF file?

Thanks

[snibgo]

As far as I know, when ImageMagick creates a multi-page tiff, all images will be the same compression (none, Group4, LZW, etc) and same type (greyscale, bilevel, etc).

[rajendram]

Thanks snibgo,

Can you pls share a php code which keeps the TIFF image quality in generated multipage tiff image ?

[snibgo]

Sorry, I don't do PHP. There may be something on the PHP forum: viewforum.php?f=10

[rajendram]

Hi,

Can you pls tell :
1. How to change compression of current tiff file to COMPRESSION_LZW.
2. How can I change Photometric to Palette from MinIsBlack.

Thanks

[snibgo]

1. In a command, include "-compression LZW". I don't know how to do this in PHP.

2. Photometric can take values min-is-black or min-is-white only.

[fmw42]

see
http://www.imagemagick.org/Usage/formats/#tiff
http://www.imagemagick.org/script/comma ... php#define
http://www.imagemagick.org/script/formats.php