如何把图片格式JPEG改为JPGL.JPEGL.GIFL.PNG

发布网友 发布时间：2022-04-08 05:05

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懂视网 时间：2022-04-08 09:27

  从上面给出的链接下载到的程序中，有用户手册告诉你怎么使用这个程序。这个程序是用Ruby语言写的，需要在Cygwin下运行，用户手册中有介绍如何安装Cygwin及其他需要的工具。程序工作流程是使用者手动输入图像名称，程序先从FTP上下载该图像，然后经过几步转换，最终转换为PNG格式。我在按照用户手册运行这个程序时没有成功，用VS2013打开get-ddsm-mammo文件查看源码，发现是从FTP上下载图像环节出了问题，做了修改后，最终运行成功。我修改后的程序如下：    

#!/usr/bin/ruby

# This program gets a specified mammogram from the DDSM website and
# converts it to a PNG image. See the help message for full details.

require 'net/ftp'


# Specify the name of the info-file.
def info_file_name
 'info-file.txt'
end

def image_names
 'image_name.txt'
end

# Get an FTP file as specified by a DDSM path (e.g.,
# /pub/DDSM/cases/cancers/cancer_06/case1141/A-1141-1.ics) and return the
# local path to the file, or return nil if the file could not be dowloaded.
def get_file_via_ftp(ddsm_path)
 ftp = Net::FTP.new('figment.csee.usf.edu')
 ftp.passive = true
 ftp.login 
 ftp.chdir(File.dirname(ddsm_path)) 
 puts File.basename(ddsm_path) 
 ftp.getbinaryfile(File.basename(ddsm_path))
 #ftp.getbinaryfile(ddsm_path)
 
 # Will be stored local to this program, under the same file name
 
 # Check to make sure that we managed to get the file.
 if !FileTest.exist?(File.basename(ddsm_path))
 puts "Could not get the file #{File.basename(ddsm_path)} from the DDSM FTP server; perhaps the server is busy."
 exit(-1)
 end 
 return File.basename(ddsm_path)
end


# Return the string input with the system's filesep at the end; if there
# is one there already then return input.
def ensure_filesep_terminated(input)
 if input[input.length-1].chr != File::SEPARATOR
 input += File::SEPARATOR
 end

 return input
end

# Check program input; input is the program input (i.e ARGV).
def check_inputs(input)
 if input.length != 1
 puts get_help
 exit(-1)
 end
 
 # See if the user wanted the help docs.
 if input[0] == '--help'
 puts get_help
 exit(-1)
 end
 
 # Check to make sure that the info file exists.
 if !FileTest.exist?(info_file_name)
 puts "The file #{info_file_name} does not exist; use catalogue-ddsm-ftp-server.rb"
 exit(-1)
 end

end

# Given the name of a DDSM image, return the path to the
# .ics file associated with the image name. If we can't find the 
# path, then we return nil.
def get_ics_path_for_image(image_name)

 # Does image_name look right?
 if image_name[/._d{4,4}_...+/].nil?
 raise 'image_name seems to be wrong. It is: ' + image_name
 end

 # Edit the image name, as .ics files have the format 'A-0384-1.ics';
 # there is no '.RIGHT_CC' (for example).
 image_name = image_name[0..(image_name.rindex('.')-1)] # Strip everything after and including the last '.'.
 image_name[1] = '-'
 image_name[6] = '-' # Change the '_'s to '-'s (better regexp-based approach?).
 image_name+='.ics' # Add the file suffix.

 # Get the path to the .ics file for the specified image.
 File.open(info_file_name) do |file|
 file.each_line do |line|
 # Does this line specify the .ics file for the specified image name?
 if !line[/.+#{image_name}/].nil?
 # If so, we can stop looking		
 return line		
 end
 end
 end
 
 # If we get here, then we did not find a match, so we will return nil.
 return nil
end

# Given a line from a .ics file, return a string that specifies the
# number of rows and cols in the image described by the line. The
# string would be '123 456' if the image has 123 rows and 456 cols.
def get_image_dims(line)
 rows = line[/.+LINESsd+/][/d+/]
 cols = line[/.+PIXELS_PER_LINEsd+/][/PIXELS_PER_LINEsd+/][/d+/]

 return rows + ' ' + cols
end

# Given an image name and a string representing the location of a
# local .ics file, get the image dimensions and digitizer name for
# image_name. Return a hash which :image_dims maps to a string of the
# image dims (which would be '123 456' if the image has 123 rows and
# 456 cols) and :digitizer maps to the digitizer name. If we can't
# determine the dimensions and/or digitizer name, the corresponding
# entry in the hash will be nil.
def get_image_dims_and_digitizer(image_name, ics_file)
 # Get the name of the image view (e.g. 'RIGHT_CC')
 image_view = image_name[image_name.rindex('.')+1..image_name.length-1]

 image_dims = nil
 digitizer = nil

 # Read the image dimensions and digitizer name from the file.
 File.open(ics_file, 'r') do |file|
 file.each_line do |line|
 if !line[/#{image_view}.+/].nil?
 # Read the image dimensions
 image_dims = get_image_dims(line)
 end
 if !line[/DIGITIZER.+/].nil?
 # Read the digitizer type from the file.
 digitizer = line.split[1].downcase # Get the second word in the DIGITIZER line.

 # There are two types of Howtek scanner and they are
 # distinguished by the first letter in image_name.
 if digitizer == 'howtek'
  if image_name[0..0].upcase == 'A'
  digitizer += '-mgh'
  elsif image_name[0..0].upcase == 'D'
  digitizer += '-ismd'
  else
  raise 'Error trying to determine Howtek digitizer variant.'
  end
 end
 end
 end
 end

 # Return an associative array specifying the image dimensions and
 # digitizer used.
 return {:image_dims => image_dims, :digitizer =>digitizer}
end

# Given the name of a DDSM image, return a string that describes
# the image dimensions and the name of the digitizer that was used to
# capture it. If 
def do_get_image_info(image_name)
 # Get the path to the ics file for image_name.
 ftp_path = get_ics_path_for_image(image_name)
 ftp_path.chomp!
 
 # Get the ics file; providing us with a string representing
 # the local location of the file.
 ics_file = get_file_via_ftp(ftp_path)

 # Get the image dimensions and digitizer for image_name.
 image_dims_and_digitizer = get_image_dims_and_digitizer(image_name, ics_file)

 # Remove the .ics file as we don't need it any more.
 File.delete(ics_file)

 return image_dims_and_digitizer
end



# Given a mammogram name and the path to the image info file, get the
# image dimensions and digitizer name string.
def get_image_info(image_name)
 # Get the image dimensions and digitizer type for the specified
 # image as a string.
 image_info = do_get_image_info(image_name)
 
 # Now output the result to standard output.
 all_ok = !image_info[:image_dims].nil? && !image_info[:digitizer].nil? # Is everything OK?
 if all_ok
 ret_val = image_info[:image_dims] + ' ' + image_info[:digitizer]
 end

 return ret_val
end

# Return a non-existant random filename.
def get_temp_filename
 rand_name = "#{rand(10000000)}" # A longish string
 if FileTest.exist?(rand_name)
 rand_name = get_temp_filename
 end

 return rand_name
end

# Retrieve the LJPEG file for the mammogram with the specified
# image_name, given the path to the info file. Return the path to the
# local file if successful. If we can't get the file, then return nil.
def get_ljpeg(image_name)
 # Get the path to the image file on the mirror of the FTP server.
 path = nil
 
 File.open(info_file_name) do |file|
 file.each_line do |line|
 if !line[/.+#{image_name}.LJPEG/].nil?
 # We've found it, so get the file.
 line.chomp!
 local_path = get_file_via_ftp(line)		
 return local_path
 end
 end
 end

 # If we get here we didn't find where the file is on the server.
 return nil
end

# Given the path to the dir containing the jpeg program, the path to a
# LJPEG file, convert it to a PNM file. Return the path to the PNM
# file.
def ljpeg_to_pnm(ljpeg_file, dims_and_digitizer)
 # First convert it to raw format.
 command = "./jpeg.exe -d -s #{ljpeg_file}"
 `#{command}` # Run it.
 raw_file = ljpeg_file + '.1' # The jpeg program adds a .1 suffix.
 
 # See if the .1 file was created.
 if !FileTest.exist?(raw_file)
 raise 'Could not convert from LJPEG to raw.'
 end

 # Now convert the raw file to PNM and delete the raw file.
 command = "./ddsmraw2pnm.exe #{raw_file} #{dims_and_digitizer}"
 pnm_file = `#{command}`
 File.delete(raw_file)
 if $? != 0
 raise 'Could not convert from raw to PNM.'
 end

 # Return the path to the PNM file.
 return pnm_file.split[0]
end

# Convert a PNM file to a PNG file. pnm_file is the path to the pnm file
# and target_png_file is the name of the PNG file that we want created.
def pnm_to_png(pnm_file, target_png_file)
 command = "convert -depth 16 #{pnm_file} #{target_png_file}"
 `#{command}`

 if !FileTest.exist?(target_png_file)
 raise 'Could not convert from PNM to PNG.'
 end

 return target_png_file
end

#write image_names to image_nama.txt
def write_image_names(name)
 namefile=File.open(image_names,'a') 
 namefile.puts name
 namefile.puts "
"
 namefile.close
end

# The entry point of the program.
def main 
 # Check to see if the input is sensible.
 #check_inputs(ARGV)
 
 #image_name = ARGV[0]

 File.open('read_names.txt','r') do |file|
 file.each_line do |line|
	 image_name = line
	 image_name.chomp!
	 
	 # Get the image dimensions and digitizer name string for the
	 # specified image.
	 image_info = get_image_info(image_name)
 
	 # Get the LJPEG file from the mirror of the FTP site, returning the
	 # path to the local file.
	 ljpeg_file = get_ljpeg(image_name)
 
	 # Convert the LJPEG file to PNM and delete the original LJPEG.
	 pnm_file = ljpeg_to_pnm(ljpeg_file, image_info)
	 File.delete(ljpeg_file)

	 # Now convert the PNM file to PNG and delete the PNG file.
	 target_png_file = image_name + '.png'
	 png_file = pnm_to_png(pnm_file, target_png_file)
	 File.delete(pnm_file)

	 # Test to see if we got something.
	 if !FileTest.exist?(png_file)
		raise 'Could not create PNG file.'
		exit(-1)
	 end

	 # Display the path to the file.
	 puts File.expand_path(png_file)

	 #write image name
	 write_image_names(image_name)

	 #exit(0)
	end 
 end
 exit(0)
end

# The help message
def get_help
 <<END_OF_HELP

 This program gets a specified mammogram from a local mirror of the
 DDSM FTP Server, converts it to a PNG image and saves it to a target
 directory; if the target directory already contains a suitably-named
 file, the download and conversion are skipped.

Call this program using:

 ruby get-ddsm-mammo.rb <image-name>

 (Note: the '\' simply indicates that the above command should be on
 one line.)

 where:

 * <image-name> is the name of the DDSM image you want to get and
 convert, for example: 'A_1141_1.LEFT_MLO'.

 If successful, the program will print the path to the PNG file of
 the requested mammogram to standard output and will return a status
 code of 0. If unsuccessful, the program should display a
 useful error message and return a non-zero status code.

END_OF_HELP
end

# Call the entry point.
main

  每处理完一张图像，程序会将图像的名称写在一个名为image_name的txt文件里，所以在运行程序前要先创建一个名为image_name的txt文件。

  最后一点要说明的是，用户手册中提到在安装Cygwin时要同时安装Ruby,因为当时的Cygwin版本较低，Ruby已不在手册中所示位置，而是单独拿出来的，要安装如下图所示的两个：

和

版权声明：本文为博主原创文章，未经博主允许不得转载。

DDSM数据库转换图像格式——LJPEG转为PNG格式

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热心网友 时间：2022-04-08 06:35