democompress2d

来自「LastWave」· 代码 · 共 64 行

#
# This is a demo file for the compress2d package
#


setproc DemoCompress2d {} "{{{} {Displays the original 'lenna' image along with its compressed version and the error image}}}" {
  StartDemo DemoCompress2d
}

setproc _DemoCompress2d0 {} {

  import args 1 System

global _scriptDirectory objCur a2
_scriptDir = _scriptDirectory[0]

# We set the current object to be the 'owtrans2' named 'a2'. 
# This variable is automatically created when the package 'owtrans2d' is loaded
# (see the file owtrans2d.pkg)
a2


# Set the current color map to be the grey one 
colormap current 'grey'

# Pick up a wavelet filter (Daubechies 8)
owt2f 'Daub8'

# Read the image we want to compress
# (The '-c' option means that the file contains characters coding 
# grey levels between 0 and 255)
iread 0 _scriptDir+'/image/lenna.dat'

# Compute the wavelet decomposition of the image on 8 levels
owt2d 8

# Compress and code this wavelet transform using a quantization step of 20
# and store the result in the file scripts/compress2d/lenna.compressed
code2 _scriptDir+'/compress2d/lenna.compressed' 20

# Decode and Decompress the corresponding file and put the
# result image in the image number 1
decode2 _scriptDir+'/compress2d/lenna.compressed' 1

# Let's display from top to bottom :
#    - The original image
#    - The compressed image
#    - The error between these two images
disp {0 1 0a2-1a2} -size 3*(256+4) 256+21 -title "Original/compressed/error"



# Let's print some stats on the error 
istats print 0a2-1a2

  printf "\nIf you want to learn how these graphs were generated look at the procedure \
'_DemoCompress2d0' in the file 'scripts/compress2d/DemoCompress2d'\n"

}

help DemoCompress2d