Solved

Cast int[] array to byte[] array?

Posted on 2009-05-14
8
1,469 Views
Last Modified: 2012-05-07
Hi,

I'm doing some image work. One image class wants a pixel buffer in the form of an int[] array, another image class wants a pixel buffer in the form of a byte[] array. Is there a way to cast between to the two? I don't want to manually iterate through each pixel, converting, it will be very slow. Example below, thanks:
Image img;
int width = img.getWidth();
int height = img.getHeight();
 
// Pixels are stored in aarrggbb format in a single integer.
int argb[] = new int[width * height];
img.getPixels(argb);
 
 
// Now this other image class wants the pixel buffer as a byte array.
byte argb2[] = new byte[width * height * 4];
ImgOther img2 = new ImgOther(argb2);
 
// But is there any way to do something like:
byte argb2[] = (byte[])argb;
ImgOther img3 = new ImgOther(argb3);

Open in new window

0
Comment
Question by:DJ_AM_Juicebox
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
8 Comments
 
LVL 86

Expert Comment

by:CEHJ
ID: 24384923
Casting is not possible in non-native languages like Java. You need to create a new array and copy
0
 
LVL 1

Expert Comment

by:mohgupta
ID: 24385588
Type casting is not possible from a data type up in hierarchy to lower data types i.e from integer to byte but the reverse is possible i.e you can convert byte to integer..
There is no other way to directly cast byte array to integer. you need to iterate or use recursion for each value.
0
 
LVL 86

Accepted Solution

by:
CEHJ earned 500 total points
ID: 24385795
>>Type casting is not possible from a data type up in hierarchy to lower data types i.e from integer to byte

It is actually (see below) but the question's really nothing to do with the casting of primitives
        int i = 128;
        byte b = (byte)i;

Open in new window

0
Technology Partners: We Want Your Opinion!

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

 

Author Comment

by:DJ_AM_Juicebox
ID: 24386241
blast!
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 24386331
:-)
0
 
LVL 92

Expert Comment

by:objects
ID: 24391732
typically in image processing you do not need to convert between array types, sounds like a limitation in the classes you are using.

0
 

Author Comment

by:DJ_AM_Juicebox
ID: 24392455
Yeah I am working on blackberry phones using j2me - the j2me Image class only has a method to give you the pixel data as an integer array. The native blackberry image class only has a constructor using a byte array. How annoying. My sadness is unprecedented.
0
 

Author Comment

by:DJ_AM_Juicebox
ID: 24392457
Oh yeah and the reason I wanted to mix the two was because the native BB image class has some rescaling functions built-in, which the j2me version amazingly does not.
0

Featured Post

Creating Instructional Tutorials  

For Any Use & On Any Platform

Contextual Guidance at the moment of need helps your employees/users adopt software o& achieve even the most complex tasks instantly. Boost knowledge retention, software adoption & employee engagement with easy solution.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
servlet example 11 59
servlet and mdb, jms error 1 57
Java program running SQL query 5 50
Find out all repos that a user is most active on Github 1 33
INTRODUCTION Working with files is a moderately common task in Java.  For most projects hard coding the file names, using parameters in configuration files, or using command-line arguments is sufficient.   However, when your application has vi…
After being asked a question last year, I went into one of my moods where I did some research and code just for the fun and learning of it all.  Subsequently, from this journey, I put together this article on "Range Searching Using Visual Basic.NET …
Viewers learn about the “for” loop and how it works in Java. By comparing it to the while loop learned before, viewers can make the transition easily. You will learn about the formatting of the for loop as we write a program that prints even numbers…
This tutorial will introduce the viewer to VisualVM for the Java platform application. This video explains an example program and covers the Overview, Monitor, and Heap Dump tabs.

726 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question