CSE 8B: Introduction to Computer Science: Java (Winter, 2006)

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Programming Assignment 7

Due Monday, March 6 at 11:59 PM.

Last modified: 3/4/06 10:50 PM. Removed non-working link to humphrey-img.txt. It's on ieng6, as documented.

Previous modifications:

Overview

You'll be writing an image-viewing program that displays a picture it reads in from a text file. The sample text file we provide is a picture of a Mars rock.

The main class will be Image. You'll run it with:

java Image imageFileName

A sample can be found in ~/../public/P7/image.jar. Run it with

java -jar ~/../public/P7/image.jar imageFileName

This program is based on programming project 3 from Chapter 19 of Absolute Java.

Requirements

The program will need to satisfy the requirements as described in the book.
It'll need to take the filename to read as a command-line argument.
It'll need a fade-in mode where instead of displaying the image directly, it fades-in the image from an all-black display to the image itself. This fade-in mode should be specified from the command mode with:
```
java Image -fadein imageFileName
```
This fade-in mode should start with all-black and you should slowly see the image come into view. It'll look as if the lights were out and the lights were slowly turned on. The fade-in should be complete within about 15 seconds or so (not several minutes, and not 1 second).

Provided files

All files are in ~/../public/P7.

There is a sample implementation of this application in a jar file: image.jar.

The humphrey-img.txt sample file from the book's CD-ROM is also there.

Hints

Think of the fade-in as a percentage from 0% to 100%. At 100%, you should be displaying 100% of each pixel's value. At 0%, you should be displaying 0% of each pixel's value (which would mean every pixel is all-white). At 50%, each pixel should display at 50% of its value.
Use a timer to adjust the fade-in percentage every fraction of a second, and repaint the image.
Be careful not to ever display more than 100% of a pixel's value.

Turnin

Create a directory on ieng6 with the following file:

Image.java

To turn in your assignment, cd to that directory and run the command

  bundleP7

and carefully follow the dialog. If it is before the due deadline and all necessary assignment files are present, this will turn in your solution files. You can run bundleP7 more than once if you want; only the last one will count.

Grading

We'll be running your program and trying it out on ieng6, so make sure you've tested your app there.

The assignment is worth 20 points. Note that we'll be testing with both the humphrey image and with another image file.

5 points: part a) of the assignment.
5 points: part b) of the assignment (scaling values).
5 points: fade-in.
5 points: Style points for your class. Good naming, not repeating yourself, correct indentation, not exceeding 80 characters per line, short methods (not too much code in any one method), etc.

As always, an additional 5% (1 point) is available if you turn the assignment in at least 24 hours early.