Legacy ImageMagick Discussions Archive

First, I sugget you upgrade to a more recent version of IM. That one is ancient. Second, I know nothing about XPM format. But converting a PNG with transparency to XPM and back to PNG works fine with no options at all, and no visible colour change. However, the alpha becomes binary, ie on or off, an...

I get an image with only part of the data. It looks like there were multiple layers but converting to png only takes one layer. In addition to fmw's comment, I see the file also has a clipping path. I'm not familiar with clipping paths, but this might be the cause of "only part of the data&quo...

Perhaps the image has transparency. Can you paste the output from "identify -verbose image.tiff" here? Put it between [ code ] and [ /code ] to preserve the formatting.

convert prova.jpg -alpha on maskcirc.png -compose Dst_In -composite -background Pink -alpha remove out.jpg JPEGs don't have a transparency channel, so I need to give it one before "-compose Dst_In -composite" will work. That leaves a transparent area outside the circle. When converted to ...

Sorry, I don't speak Perl.

I forgot to mention: I use Q16 IM, which will give different results to your Q8.

Try ...

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"%IMG6846%convert" alpha-gradient.png  -quantize RGB -alpha off -dither None -colors 256 -alpha on a8.png

... which gives a similar result to that old IM version but (I would argue) even more fantastic.

Yes, it gives me the warning but that doesn't stop it working. I mention it only because that tag might, theoretically, be what distinguishes the OP's tiffs that don't work under 6.5.2-5 from those that do.

Yup, "-normalize" needs "-set colorspace RGB" to work in the way we might expect.

So does "-threshold", "-equalize" and even "-contrast-stretch 0" though not "-auto-level".

What version of IM? What platform? Can you supply an example has this problem?

Both commands work without problems on v6.5.8-8 on Windows 7.

With more recent versions, I get a warning:

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identify.exe: Wrong data type 3 for "GainControl"; tag ignored. `TIFFReadCustomDirectory' @ warning/tiff.c/TIFFWarnings/821.

I find the Windows command processor usually mucks up commands containing UTF-8 text. I'm sure there is a workaround, but I don't know what it is. Instead, I put the text in a file, saved as UTF-8, and "@" caption. Thus ... "%IMG%convert" -background lightblue -fill blue -gravity...

In the UK, a 4TB external disk costs around £130. If an image takes 0.2 GB, the disk would hold 20,000 images. So less than a penny per image, and the cost keeps dropping. Double or treble that for backups, of course. But still less than the cost of negative sleeves and binders. Scaling algorithms k...

The oldest version I have is 6.5.8-8, on Windows 7. The command ...

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"%IMG658%identify" -format "%z\n %r\n %n\n" Brueckeninsp-123.tif

... works with no problem.

Regarding file sizes, are you using a "-compress" option? You might find that this significantly reduces file size without losing any data (at the expense of processing time). Eg:

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convert in.tiff -compress Zip out.tiff

If you want to replace all colours apart from a specified one with transparency, use "+transparent". See http://www.imagemagick.org/script/command-line-options.php#transparent convert input.jpg +transparent "#1A1414" output.jpg Your IM version is also very old; I don't know (and ...

Legacy ImageMagick Discussions Archive

Search found 12163 matches

Re: Converting .png to .xpm with transparency and RGB colors

Re: Error converting tiff

Re: Error converting tiff

Re: Set background color on composite

Re: Color reduction doesn't work well with alpha PNGs

Re: Color reduction doesn't work well with alpha PNGs

Re: Problem with ImageMagick 6.5.2-5

Re: Normalize filter does not work anymore

Re: Error converting tiff

Re: Problem with ImageMagick 6.5.2-5

Re: Caption error with french accent

Re: Scaling scans of analog photo negatives

Re: Problem with ImageMagick 6.5.2-5

Re: Scaling scans of analog photo negatives

Re: Problem with +transparent and +opaque