$ convert a.png -background  skyblue -flatten a_flatten.jpg

convert img1.png -background white -flatten img1-white.png

convert -flatten img1.png img1-white.png
convert sourceimage.png -background BackgroundColor -flatten destinationimage.png

convert image.png -alpha off image.png

xc:none or -background none

animate   sphere*.gif

convert   -delay 20   -loop 0   sphere*.gif   animatespheres.gif

convert -size 200x100 big.gif -resize 200x10 small.gif



convert big.gif -coalesce coalesce.gif
convert -size 200x100 coalesce.gif -resize 200x10 small.gif



  convert -channel RGBA -fill white \
          \( medical.gif -repage 100x100+34+65 -coalesce -set delay 200 \) \
          \( +clone -motion-blur 0x20+90 -blur 0x3 -colorize 100% \
                +clone -colorize 30%  +swap  -composite  -set delay 10  \) \
          \( +clone -roll +0-20 -blur 0x3 -colorize 30% \
             -motion-blur 0x15+90 -motion-blur 0x15-90 -set delay 10 \) \
          \( +clone -colorize 30% \
             -motion-blur 0x30+90 -blur 0x5 -crop +0+10\! \) \
          \( +clone -motion-blur 0x50+90 -blur 0x2 -crop +0+20\! \) \
          \( +page -size 100x100 xc:none -set delay 200 \) \
          -set dispose background -coalesce   -loop 0     teleport.miff
  gif_anim_montage teleport.miff teleport_frames.png


  convert teleport.miff teleport_thres.gif
  gif_anim_montage teleport_thres.gif teleport_thres_frames.gif



 identify -format "Number of Frames: %n\n" speed.miff | head -1
 identify -format "Colors in Frame %p: %k\n"  speed.miff

  convert speed.miff +append  -format "Total Number of Colors: %k"  info:

-thumbnail "120x90>" -quality 95 -background transparent -gravity Center -extent 120x90 img.png

convert.exe -thumbnail "120x90>" -quality 95 -background transparent -gravity Center -extent 120x90 monalisa171p.jpg monalisa171p_thumb.jpg




 <?php
exec(" convert -size 500x300 xc:white -font ../jd.ttf -pointsize 30 \\
-draw \"gravity center fill black text 0,0 'Center' \" \\
-draw \"gravity North fill black text 0,0 'North' \" \\
-draw \"gravity Northeast fill black text 0,0 'Northeast' \" \\
-draw \"gravity East fill black text 0,0 'East' \" \\
-draw \"gravity Southeast fill black text 0,0 'Southeast' \" \\
-draw \"gravity South fill black text 0,0 'South' \" \\
-draw \"gravity Southwest fill black text 0,0 'Southwest' \" \\
-draw \"gravity West fill black text 0,0 'West' \" \\
-draw \"gravity Northwest fill black text 0,0 'Northwest' \" \\
-bordercolor black -border 1x1 gravity.jpg" );
?> 
 <?php
// Array of values
$arr = array("North", "Northeast", "East", "Southeast", "South", "Southwest", "West", "Northwest",
 "Center");
// Set $command
$command ="";
// Setup loop for the array
foreach ($arr as $value) {
// Create the individual draw commands and add them to the previous value of $command
$command .= " -draw \"gravity $value fill black text 0,0 $value \" " ;  }
// Create the image using php
exec(" convert -size 500x300 xc:white -font ../jd.ttf -pointsize 30 \\
$command bordercolor black -border 1x1 gravity.jpg" );
?> 


convert -size 300x300 xc:white -stroke black \
 -linewidth 3 -fill white -draw "rectangle 15,15 285,285" \
 -linewidth 2 -draw "rectangle 120,80 260,160" \
cv.png

The four corners of the inner rectangle are (120,80), (260,80), (120,160), (260,160) and the center is (190,120). 
convert cv.png -draw "text 190,120 'abc'" test1.png

 convert dragon.gif   -background Khaki  label:'Faerie Dragon' \
          -gravity Center -append    anno_label.jpg

convert dragon.gif   -background Orange  label:'Faerie Dragon' \
          +swap  -gravity Center -append    anno_label2.jpg

 convert dragon.gif \
          -gravity South   -background Plum   -splice 0x18 \
          -annotate +0+2 'Faerie Dragon'   anno_splice.gif

  montage -label "Faerie Dragon" dragon.gif \
          -font Candice -pointsize 15 \
          -frame 5  -geometry +0+0 anno_montage2.jpg

composite -gravity center  castle.gif  frame.gif  castle_button.gif


composite -geometry +31+105  hand_point.gif dragon.gif \
            dragon_claw_pointed.jpg


  composite -geometry +31+105  hand_point.gif dragon.gif \
            dragon_claw_pointed.jpg

our dragon image before using "-compose bumpmap" to draw it on a paper scroll image.


  composite \( dragon.gif -resize 50% \) scroll.gif \
            -compose bumpmap -gravity center   dragon_scroll.gif

 convert logo.jpg  -font Arial -pointsize 20 \
          -draw "gravity south \
                 fill black  text 0,12 'Copyright' \
                 fill white  text 1,11 'Copyright' " \
          wmark_text_drawn.jpg

 convert -size 140x80 xc:none -fill grey \
          -gravity NorthWest -draw "text 10,10 'Copyright'" \
          -gravity SouthEast -draw "text 5,15 'Copyright'" \
          miff:- |\
    composite -tile - logo.jpg  wmark_text_tiled.jpg


  composite -dissolve 25% -gravity south \
            wmark_image.png   logo.jpg  wmark_dissolve.jpg

composite -gravity center overlay.png  background.jpg  result1.jpg


Re: Layering Images with convert -composite with gravity cen

Postby anthony » 2012-01-27T04:39:28+00:00
You can start by using the operators in the right order. That is set the 'settings' first.
"Composite" command is 'read all settings then apply ONE operation, type of command (traditional UNIX)
"Convert" is a 'do options as you see them', with MULTIPLE operations possible. (script-like command)

Code: Select all
    convert  background.jpg  tool_marker.png -geometry +50+50 -composite result4.jpg



  convert rose:   -modulate 0     mod_bright_0.gif
  convert rose:   -modulate 50    mod_bright_50.gif
  convert rose:   -modulate 80    mod_bright_80.gif
  convert rose:   -modulate 100   mod_bright_100.gif
  convert rose:   -modulate 150   mod_bright_150.gif
  convert rose:   -modulate 200   mod_bright_200.gif


  convert rose:   -modulate 100,100,0      mod_hue_0.gif
  convert rose:   -modulate 100,100,33.3   mod_hue_33.gif
  convert rose:   -modulate 100,100,66.6   mod_hue_66.gif
  convert rose:   -modulate 100,100,100    mod_hue_100.gif
  convert rose:   -modulate 100,100,133.3  mod_hue_133.gif
  convert rose:   -modulate 100,100,166.6  mod_hue_166.gif
  convert rose:   -modulate 100,100,200    mod_hue_200.gif

  convert -size 40x20 xc:red  xc:blue \
          -append   -rotate 90    append_rotate.gif



convert -size 30x30 xc:black -fill white  -draw 'circle 15,15 5,15' \
          \( +clone -shade 110x90 -normalize -negate +matte \) \
          \( +clone -clone -2 -compose Plus -composite \) \
          \( -clone 0 -shade 110x50 -normalize +matte \) \
          \( +clone -gamma 1,0,0 \) \
          \( -clone 2,-1  -compose Multiply -composite \) \
          -append  seq_process_fx.gif

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