Welcome to the Java Programming Forums


The professional, friendly Java community. 21,500 members and growing!


The Java Programming Forums are a community of Java programmers from all around the World. Our members have a wide range of skills and they all have one thing in common: A passion to learn and code Java. We invite beginner Java programmers right through to Java professionals to post here and share your knowledge. Become a part of the community, help others, expand your knowledge of Java and enjoy talking with like minded people. Registration is quick and best of all free. We look forward to meeting you.


>> REGISTER NOW TO START POSTING


Members have full access to the forums. Advertisements are removed for registered users.

Results 1 to 2 of 2

Thread: Get greyscale pixel information from a png file

  1. #1
    Junior Member
    Join Date
    Jan 2018
    Posts
    1
    Thanks
    0
    Thanked 0 Times in 0 Posts

    Cool Get greyscale pixel information from a png file

    I have built a neural network that recognizes handwritten digits in java. This neural network accepts an array of greyscale values for each pixel in the image. I have already treined the network using the mnist database of handwritten digits. I would like to query it based on an image that I have made that is saved as a png file. How can get the greyscale information for each pixel so I can properly interface with my network. Each image is 28x28 so each array that is read as the input contains 784 elements.

    Here is an example file which evaluates as a 7:
    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,84,185,159,151,60,36,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,222,254,254,254,254,241,198,198,198,198,198,198,198,198,170,52,0,0,0,0,0,0,0,0,0,0,0,0,67,114,72,114,163,227,254,225,254,254,254,250,229,254,254,140,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,17,66,14,67,67,67,59,21,236,254,106,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,83,253,209,18,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,22,233,255,83,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,129,254,238,44,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,59,249,254,62,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,133,254,187,5,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,9,205,248,58,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,126,254,182,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,75,251,240,57,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,19,221,254,166,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,3,203,254,219,35,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,38,254,254,77,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,31,224,254,115,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,133,254,254,52,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,61,242,254,254,52,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,121,254,254,219,40,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,121,254,207,18,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0

  2. #2
    Super Moderator pbrockway2's Avatar
    Join Date
    Jan 2012
    Posts
    987
    Thanks
    6
    Thanked 206 Times in 182 Posts

    Default Re: Get greyscale pixel information from a png file

    I would like to query it based on an image that I have made that is saved as a png file. How can get the greyscale information for each pixel so I can properly interface with my network. Each image is 28x28 so each array that is read as the input contains 784 elements.
    Strictly speaking what you want is an array of pixel values, what you are starting with is a .png file.

    Reading image files is discussed in Sun's Tutorial's Reading/Loading an Image page and methods for extracting the pixels are documented in the BufferedImage API docs.[COLOR="Silver"]
    Last edited by pbrockway2; January 4th, 2018 at 08:01 PM. Reason: edit: double post

Similar Threads

  1. How do I update information in a file?
    By ineedahero in forum What's Wrong With My Code?
    Replies: 1
    Last Post: September 25th, 2013, 02:42 PM
  2. Replies: 21
    Last Post: May 5th, 2013, 07:04 PM
  3. Problems reading a pgm-file (pixel gray map).
    By morob05 in forum File I/O & Other I/O Streams
    Replies: 11
    Last Post: December 25th, 2012, 06:54 AM
  4. Reading from Text File and Processing Information
    By royalslim in forum File I/O & Other I/O Streams
    Replies: 2
    Last Post: December 13th, 2010, 02:27 PM
  5. select a color from a png file
    By strider in forum Java Theory & Questions
    Replies: 2
    Last Post: December 2nd, 2010, 05:20 AM

Tags for this Thread