Problem with generating reflection

[ssaann]

Trying the example titled ' Gradient Attenuation' at
http://www.imagemagick.org/Usage/advanced/#reflections doesn't seem to work for me on a mac with version '6.7.9-0' using the same example image as on the webpage.

A black bar appears instead of the reflected image. Any ideas if it's platform/installation specific or anything else?

thanks!

[pipitas]

Trying the example titled ' Gradient Attenuation' at
http://www.imagemagick.org/Usage/advanced/#reflections doesn't seem to work for me on a mac with version '6.7.9-0' using the same example image as on the webpage.

It works for me on Mac OS X Lion with the same version number (installed via 'MacPorts'):

Code: Select all

Version: ImageMagick 6.7.9-0 2012-08-17 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2012 ImageMagick Studio LLC
Features:  OpenCL HDRI  

installed with this command:

Code: Select all

sudo port -p install ImageMagick +graphviz+hdri+jbig+jpeg2+lqr+mpeg+pango+perl+q16+rsvg+wmf

Which is your Mac OS X version?

How did you install your ImageMagick?

What's the exact version of ImageMagick? Please provide the full output of

Code: Select all

convert -version

and

Code: Select all

convert -list configure

A black bar appears instead of the reflected image. Any ideas if it's platform/installation specific or anything else?

How did you try to view your output?

For me the output looks Ok in 'Preview.app' as well as with ImageMagick's own 'display', just like the original one:

[ssaann]

I am on latest Mountain Lion, I reinstalled IM with same command as you used, earlier I had used - 'sudo port -p install ImageMagick'.

Now i used - 'sudo port -p install ImageMagick +graphviz+hdri+jbig+jpeg2+lqr+mpeg+pango+perl+q16+rsvg+wmf'

My version:
Version: ImageMagick 6.7.9-0 2012-08-22 Q16 http://www.imagemagick.org
Copyright: Copyright (C) 1999-2012 ImageMagick Studio LLC
Features: OpenCL HDRI

Output from:
$convert -list configure

Path: /opt/local/lib/ImageMagick-6.7.9/config/configure.xml

Name Value
-------------------------------------------------------------------------------
CC /usr/bin/clang
CFLAGS -I/opt/local/include/lqr-1 -I/opt/local/include/glib-2.0 -I/opt/local/lib/glib-2.0/include -I/opt/local/include -pipe -O2 -arch x86_64 -Wall -D_THREAD_SAFE -pthread
CODER_PATH /opt/local/lib/ImageMagick-6.7.9/modules-Q16/coders
CONFIGURE ./configure '--prefix=/opt/local' '--enable-shared' '--enable-static' '--disable-ltdl-install' '--with-frozenpaths' '--with-dps' '--with-bzlib' '--with-fontconfig' '--with-gslib' '--with-jpeg' '--with-lcms' '--with-png' '--with-tiff' '--with-webp' '--with-zlib' '--with-modules' '--with-xml' '--with-x' '--without-fpx' '--with-gs-font-dir=/opt/local/share/fonts/urw-fonts' '--with-gvc' '--with-openexr' '--enable-hdri' '--with-jbig' '--with-jp2' '--with-lqr' '--with-pango' '--with-perl=/opt/local/bin/perl' '--with-quantum-depth=16' '--with-rsvg' '--with-wmf' 'CC=/usr/bin/clang' 'CFLAGS=-pipe -O2 -arch x86_64' 'LDFLAGS=-L/opt/local/lib -arch x86_64' 'CPPFLAGS=-I/opt/local/include' 'CXX=/usr/bin/clang++' 'CXXFLAGS=-pipe -O2 -arch x86_64'
CONFIGURE_PATH /opt/local/etc/ImageMagick/
COPYRIGHT Copyright (C) 1999-2012 ImageMagick Studio LLC
CPPFLAGS -I/opt/local/include/ImageMagick
CXX /usr/bin/clang++
CXXFLAGS -pipe -O2 -arch x86_64 -D_THREAD_SAFE -pthread
DEFS -DHAVE_CONFIG_H
DELEGATES bzlib fftw fontconfig freetype gs gvc jbig jpeg jng jp2 lcms2 lqr lzma openexr pango png rsvg tiff x11 xml wmf zlib
DISTCHECK_CONFIG_FLAGS 'CC=/usr/bin/clang' 'CFLAGS=-pipe -O2 -arch x86_64' 'CPPFLAGS=-I/opt/local/include' 'CXX=/usr/bin/clang++' 'LDFLAGS=-L/opt/local/lib -arch x86_64' --disable-deprecated --with-quantum-depth=16 --with-umem=no --with-autotrace=no --with-fpx=no --with-fontpath= --with-gs-font-dir=/opt/local/share/fonts/urw-fonts --with-perl=/opt/local/bin/perl
DOCUMENTATION_PATH /opt/local/share/doc/ImageMagick-6.7.9
EXEC-PREFIX /opt/local
EXECUTABLE_PATH /opt/local/bin
FEATURES HDRI OpenCL
FILTER_PATH /opt/local/lib/ImageMagick-6.7.9/modules-Q16/filters
HOST x86_64-apple-darwin12.0.0
INCLUDE_PATH /opt/local/include/ImageMagick
LDFLAGS -L/opt/local/lib -L/opt/local/lib -arch x86_64 -L/opt/local/lib -L/opt/local/lib
LIB_VERSION 0x679
LIB_VERSION_NUMBER 6,7,9,0
LIBRARY_PATH /opt/local/lib/ImageMagick-6.7.9
LIBS -lMagickCore -llcms2 -ltiff -lfreetype -ljpeg -L/opt/local/lib -llqr-1 -lglib-2.0 -lintl -lfftw3 -L/opt/local/lib -lfontconfig -lXext -lSM -lICE -lX11 -lXt -L/opt/local/lib -llzma -lbz2 -lz -lm -Wl,-framework,OpenCL -lpthread -lltdl
NAME ImageMagick
PCFLAGS
PREFIX /opt/local
QuantumDepth 16
RELEASE_DATE 2012-08-22
SHARE_PATH /opt/local/share/ImageMagick-6.7.9
SVN_REVISION 8971
TARGET_CPU x86_64
TARGET_OS darwin12.0.0
TARGET_VENDOR apple
VERSION 6.7.9
WEBSITE http://www.imagemagick.org

Path: [built-in]

Name Value
-------------------------------------------------------------------------------
NAME ImageMagick

Ran this command as is -
$convert pokemon.gif -alpha on \( +clone -flip -size 64x28 gradient:gray40-black -alpha off -compose CopyOpacity -composite \) -append -gravity North -crop 100x100+0-5\! -background black -compose Over -flatten reflect_attenuated.png

It generates this image -
http://www.tiikoni.com/tis/view/?id=446537b

This image doesn't show any reflection in preview.app or any other viewers.

[pipitas]

Ok, I can confirm what you see -- the following command does NOT work to create the reflection when using v6.7.9-0 Q16 (it DID work in v6.7.6-9 though):

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  convert              \
    pokemon.gif        \
   -alpha on           \
    \(                         \
        +clone                 \
        -flip                  \
        -size 64x28            \
         gradient:gray40-black \
        -alpha off             \
        -compose CopyOpacity   \
        -composite             \
    \)                        \
    -append             \
    -gravity North      \
    -crop 100x100+0-5\! \
    -background black   \
    -compose Over       \
    -flatten            \
     reflect_attenuated.png

Using '-alpha on' in the clone does make the refection visible, but it's without the transparency of course.

Switching over to my (selfcompiled) version v6.7.6-9 Q16 has this same command working.

The command which I had used (and which still works on v6.7.9-0 Q16, producing the reflection image in my previous answer) is this:

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  convert              \
    pokemon.gif        \
    \(                     \
       +clone              \
       -flip               \
       -fill black         \
       -colorize 65%       \
    \)                     \
    -append            \
    -size 100x100      \
     xc:black          \
    +swap              \
    -gravity North     \
    -geometry +0+5     \
    -composite         \
     reflect_colored.png

[pipitas]

Ok, I can confirm what you see -- the following command does NOT work to create the reflection when using v6.7.9-0 Q16 (it DID work in v6.7.6-9 though):

Code: Select all

  convert              \
    pokemon.gif        \
   -alpha on           \
    \(                         \
        +clone                 \
        -flip                  \
        -size 64x28            \
         gradient:gray40-black \
        -alpha off             \
        -compose CopyOpacity   \
        -composite             \
    \)                        \
    -append             \
    -gravity North      \
    -crop 100x100+0-5\! \
    -background black   \
    -compose Over       \
    -flatten            \
     reflect_attenuated.png

Upon closer look, the problem seems to be connected with the 'gradient:gray40-black' part of the command. Replacing this with 'gradient:white-black' made it work (but of course, it isn't the wanted output...).

'gradient:gray70-black' also works, for example. It produces a similar result as 'gradient:gray40-black' did in v6.7.6-9 for the brighter part of the reflection, but the gradient does much more quickly fade into black here.

Since both versions do produce the very same PNG output with 'convert -size 64x28 :gray40-black gradient.png' I think the change comes from a different behavior of the 'compose Over' part of the command...

[ssaann]

thanks for trying it out
Yes with gradient:gray70-black it works but the result is not what I want.

Is there another way to apply gradient fade to the image and maybe I can pipeline multiple steps to crop and combine images?

[pipitas]

Is there another way to apply gradient fade to the image and maybe I can pipeline multiple steps to crop and combine images?

Did you try the command I originally used to test? This one:

Code: Select all

 convert                   \
    pokemon.gif            \
    \(                     \
       +clone              \
       -flip               \
       -fill black         \
       -colorize 65%       \
    \)                     \
    -append                \
    -size 100x100 xc:black \
    +swap                  \
    -gravity North         \
    -geometry +0+5         \
    -composite             \
     reflect_colored.png

[ssaann]

But that one doesn't produce a gradient in the reflection, which gradually fades/blurs out, or does it?
for me it creates a reflection that goes up to the bottom of image without any gradient..

[fmw42]

This works for me, note the size must be 64x64 not 64x28


convert pokemon.gif -alpha on \
\( +clone -flip \( -size 64x64 gradient:"gray70-black" \) -alpha off -compose Copy_Opacity -composite \) \
-append -gravity North -crop 100x100+0-5\! -background black -compose Over -flatten pokemon_reflect_attenuated.png

[ssaann]

This should do, works great!

thanks a lot for your help. much appreciated..

[ssaann]

Found another solution from here for someone looking for it -
viewtopic.php?f=1&t=15371

[fmw42]

Found another solution from here for someone looking for it -
viewtopic.php?f=1&t=15371

Yes, those were my responses/solutions also.