How can I convert grayscale blob to PNG?

[star117]

HI!
I find way to convert 16 bits grayscale blob to PNG image from file:

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      convert -size 600x600 gray:rawdata.dat -depth 16 out.png

its working.
But I want to make this by PHP extension Imagick. Its not working.

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$fill="...long string witch have 16 bits pairs of grayscale...";
$im=new Imagick();
$im->setResolution($width,$height);
$im->readImageBlob($fill);
...exception...

in readImageBlob(...) I see exception:

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PHP Fatal error:  Uncaught exception 'ImagickException' with message 'no decode delegate for this image format `' @ error/blob.c/BlobToImage/364' in ...

Question is: How can I read blob (and convert to png, off course) with Imagick as in ImageMagick CLI?

P.S.: rawdata.dat and $fill have same data.

[dlemstra]

I am not an IMagick expert but I suspect you must tell it the format first. It looks like you can do that with $im->setFormat("gray").

[star117]

Yes, I agree with you. But then I try to setFormat() Imagick throw exception like "Can not process empty Imagick object"...

[star117]

Anyone can help? Maybe guru

[Bonzo]

Imagick is not written or maintained by the Imagemagick developers and there are a very few users here. I think I have seen an Imagick forum somewhere and it might be best asking them.

[snibgo]

I've never used Imagick, but the documentation http://php.net/manual/en/imagick.setsize.php says you need "setSize()".

"setResolution()" corresponds to command-line "-density" which is unimportant. At the CLI, "-size" is essential for raw images because there is no widthXheight metadata.

[star117]

I've never used Imagick, but the documentation http://php.net/manual/en/imagick.setsize.php says you need "setSize()".

"setResolution()" corresponds to command-line "-density" which is unimportant. At the CLI, "-size" is essential for raw images because there is no widthXheight metadata.

HI!
I try to setSize() before make readImageBlob() with same result, that's doesn't work.
I started thinking about I cannot make it in Imagick.

[snibgo]

What does your code now contain? What is the error message? What version of ImageMagick are you using?

[star117]

What does your code now contain? What is the error message? What version of ImageMagick are you using?

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...
$im=new Imagick();
$im->setSize($width,$height);
$im->readImageBlob($fill);
// формат
$im->setImageFormat("png");
$im->setOption('png:bit-depth', "16");
$im->setOption('png:color-type', 5);
$im->writeImage($outfpath);
$im->destroy();
...

Error is:

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PHP Fatal error:  Uncaught exception 'ImagickException' with message 'no decode delegate for this image format `' @ error/blob.c/BlobToImage/364' in ...

error occured in line with readImageBlob(...).

$fill - is string contains sequence pairs of symbols represented value of 16 bit big-endian.

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Imagick version: array (
  'versionNumber' => 1655,
  'versionString' => 'ImageMagick 6.7.7-10 2014-03-08 Q16 http://www.imagemagick.org',
)

Have some ideas?

[snibgo]

Why don't you set the format to "gray" before reading it?