The picture colors was changed obviously after convert

[needkane]

origin: http://img.dajia365.com/8d7f61050f7075e ... 99da9f.jpg
command : convert 8d7f61050f7075ec55eaff82a999da9f.jpg -thumbnail 370x370 -quality 100 result.jpg

we found result.jpg colors was changed obviously.
And we test others parameter value,there's not no change.

convert 8d7f61050f7075ec55eaff82a999da9f.jpg -thumbnail 370x370 -quality 90 result.jpg //ok
convert 8d7f61050f7075ec55eaff82a999da9f.jpg -thumbnail 371x371 -quality 100 result.jpg //ok

[dlemstra]

Can you specify your operating system and the output from convert - version

[needkane]

OS is Ubuntu 12.04 , imagick 6.9.1

[needkane]

Can you specify your operating system and the output from convert - version

convert -version
Version: ImageMagick 6.9.1-2 Q16 x86_64 2015-05-18 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2015 ImageMagick Studio LLC
License: http://www.imagemagick.org/script/license.php
Features: DPC OpenMP
Delegates (built-in): bzlib djvu fftw fontconfig freetype jng jpeg lcms lqr lzma openexr pangocairo png tiff webp x xml zlib

[dlemstra]

The link of your original file seems to be missing?

[needkane]

The link of your original file seems to be missing?

origin: http://s3-us-west-2.amazonaws.com/qiniu-bs/370blue

[fmw42]

It would be helpful to see your JPG result that you say has changed colors. JPG is a lossy compression and will always change pixel values. If you say the actual overall color has changed. That is different. It could be a bug in IM or that you are using an older version of libjpeg.

I have tested your command on this image in IM 6.9.2.3 Q16 Mac OSX with jpeg 9a_1 (from MacPorts) and it works fine for me. I see no color changes.

[needkane]

It would be helpful to see your JPG result that you say has changed colors. JPG is a lossy compression and will always change pixel values. If you say the actual overall color has changed. That is different. It could be a bug in IM or that you are using an older version of libjpeg.

I have tested your command on this image in IM 6.9.2.3 Q16 Mac OSX with jpeg 9a_1 (from MacPorts) and it works fine for me. I see no color changes.

I use libjpeg.so.8

[fmw42]

Perhaps you should upgrade both IM and libjpeg. Also again, it would be interesting to see your resulting image that you say is changed?

[needkane]

Perhaps you should upgrade both IM and libjpeg. Also again, it would be interesting to see your resulting image that you say is changed?

It's also failed with use imagick 6.9.2-3
ldd /usr/local/bin/convert |grep jpeg
libjpeg.so.8 => /usr/lib/x86_64-linux-gnu/libjpeg.so.8 (0x00007fd0d99d9000)
convert -version
Version: ImageMagick 6.9.2-3 Q16 x86_64 2015-10-22 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2015 ImageMagick Studio LLC
License: http://www.imagemagick.org/script/license.php
Features: Cipher DPC OpenMP
Delegates (built-in): bzlib djvu fftw fontconfig freetype gvc jbig jng jpeg lcms lqr lzma openexr pangocairo png tiff webp wmf x xml zlib

cmd :convert 370blue -thumbnail 370x370 -quality 100 result.jpg

origin:http://s3-us-west-2.amazonaws.com/qiniu-bs/370blue
result:http://7xlywb.com1.z1.glb.clouddn.com/result.jpg

[fmw42]

convert 370blue -thumbnail 370x370 -quality 100 result.jpg

your input image 370blue is missing a suffix.

This works fine for me on IM 6.9.2.4 Q16 Mac OSX

Code: Select all

convert 370blue.jpeg -thumbnail 370x370 -quality 100 result.jpg

[needkane]

convert 370blue -thumbnail 370x370 -quality 100 result.jpg

your input image 370blue is missing a suffix.

This works fine for me on IM 6.9.2.4 Q16 Mac OSX

Code: Select all

convert 370blue.jpeg -thumbnail 370x370 -quality 100 result.jpg

At 2015-09-24 you say:

fmw42 wrote:
It would be helpful to see your JPG result that you say has changed colors. JPG is a lossy compression and will always change pixel values. If you say the actual overall color has changed. That is different. It could be a bug in IM or that you are using an older version of libjpeg.

I have tested your command on this image in IM 6.9.2.3 Q16 Mac OSX with jpeg 9a_1 (from MacPorts) and it works fine for me. I see no color changes



Now ,i use imagick 6.9.2-3 is failed