tags:

views:

80

answers:

1
Q: 

opencv: execution halting at double pointer arithmetic for image pixel access

A single channel image is my input. ( defalut IPL_DEPTH_8U)

I am multiplying each pixel of my input image with scalar floating point numbers like 2.8085 (as a part of my algorithm).

So this needs me to increase the depth and change the image type to IPL_DEPTH_64F

But whenever I am trying to change my image datatype to IPL_DEPTH_64F and have a double* to access each pixel, my program execution stops abruptly, cribbing that "file.exe has stopped working. A problem caused the program to stop working."

Does it mean, my processor is not able to handle the double ptr arithmetic ???

+1  A: 

You have to create a new image - I'd recommend making a new image of depth IPL_DEPTH_64F and setting each pixel to the appropriate value (2.8085*value).

Also, can you post the code you used?

Jacob  2010-02-16 02:50:37
U were right. It was easier to create a new image of 64depth and then do a cvconvertscale rather than pointer typecasting.
Geeta V  2010-02-16 17:36:34
Pointer typecasting would not have worked since the memory allocated would've been `sizeof(uchar)*heigh*width` for `IPL_DEPTH_8U`
Jacob  2010-02-16 18:07:31

related questions

Java: Double Value Comparison
Java doesn't seem to be comparing Doubles right.
How do you round a Double down to the nearest integer in VB .NET?
Should I use decimal, float or double for this simple math result?
Check variable type in C++
Float or Double Special Value
How do I convert a double into a string in C++?
Decimal vs Double Speed
Using double, return string
Retain precision with Doubles in java.
static_cast confusion caused by inconsistencies
What column type in Oracle can take full range of java double values
Smarty replace text with double quotes
Firefox sending request twice
Which is the best way to compare the integer part of two non-integer numbers?
Compare double in VBA precision problem
Applications using Decimal versus double . . .
Converting a byte() array to a double in VB.Net
Double quotes in Oracle Alias
Letters within integers. What are they?
Are doubles faster than floats in c#?
How to convert a unmanaged double to a managed string?
Why would I use 2's complement to compare two doubles instead of comparing their differences against an epsilon value?
Can cout alter variables somehow?
Most Efficient Way to Test Object Type