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Re: ImageIO/BufferedImage behaving inconsistently from one day to the next.

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On 6/20/2012 9:58 PM, Fred Greer wrote:
> On Wed, 20 Jun 2012 21:23:35 -0700, Knute Johnson wrote:
>
>> On 6/20/2012 5:23 PM, Fred Greer wrote:
>>> On Wed, 20 Jun 2012 08:39:37 -0700, Knute Johnson wrote:
>>>
>>>> On 6/19/2012 7:31 PM, Fred Greer wrote:
>>>>> I have code that used to work perfectly, which processes images in
>>>>> certain ways, and today it suddenly was not working. I hadn't changed
>>>>> the code at all. I tracked the problem down to spurious
>>>>> IllegalArgumentExceptions being thrown by this code:
>>>>>
>>>>> public class ImageUtils {
>>>>>
>>>>>        private static float[] BLUR = {0.1111111, 0.1111111, 0.1111111,
>>>>>                                       0.1111111, 0.1111111, 0.1111111,
>>>>>                                       0.1111111, 0.1111111, 0.1111111}
>>>>> ...
>>>>>        public static BufferedImage blur (BufferedImage img) {
>>>>>            Kernel k = new Kernel(3, 3, BLUR);
>>>>>            ConvolveOp co = new ConvolveOp(k, ConvolveOp.EDGE_NO_OP,
>>>>>            null); BufferedImage dest = new
>>>>>            BufferedImage(img.getWidth(),
>>>>>                img.getHeight(),img.getType());
>>>>
>>>> Please try just putting BufferedImage.TYPE_INT_ARGB here instead of
>>>> getting the type from the other image and tell us what happens.
>>>
>>> Are 32-bit PNGs loaded via ImageIO.read guaranteed to be ARGB, or at
>>> least compatible with ARGB destination images for the purposes of
>>> ConvolveOp and friends?
>>
>> I am certainly no expert but I would think that a PNG file would create
>> an ARGB image without any problems and I was curious what would happen.
>>
>> The other option is to not even create a new image and just convert the
>> one you have by putting null destination field.
>
> I thought that didn't work, at least for some transformations? At the
> same time, I prefer to minimize mutation and prefer creating new objects.
> There's much less scope for concurrency problems and some other sorts of
> bugs that way, particularly when a single object is used in various
> places and none of them expect it to change because of one of the other
> places.
>

All right then, that's all I've got for you.

-- 

Knute Johnson

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ImageIO/BufferedImage behaving inconsistently from one day to the next. Fred Greer <fggreer@nospam.invalid> - 2012-06-20 02:31 +0000
  Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. markspace <-@.> - 2012-06-19 19:38 -0700
    Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Fred Greer <fggreer@nospam.invalid> - 2012-06-20 03:07 +0000
  Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. markspace <-@.> - 2012-06-19 20:22 -0700
    Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. "John B. Matthews" <nospam@nospam.invalid> - 2012-06-20 14:26 -0400
  Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Patricia Shanahan <pats@acm.org> - 2012-06-19 20:38 -0700
    Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Fred Greer <fggreer@nospam.invalid> - 2012-06-20 04:08 +0000
  Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Roedy Green <see_website@mindprod.com.invalid> - 2012-06-20 01:16 -0700
    Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Joerg Meier <joergmmeier@arcor.de> - 2012-06-20 11:44 +0200
    Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Fred Greer <fggreer@nospam.invalid> - 2012-06-21 00:22 +0000
  Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Knute Johnson <nospam@knutejohnson.com> - 2012-06-20 08:39 -0700
    Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Fred Greer <fggreer@nospam.invalid> - 2012-06-21 00:23 +0000
      Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Knute Johnson <nospam@knutejohnson.com> - 2012-06-20 21:23 -0700
        Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Fred Greer <fggreer@nospam.invalid> - 2012-06-21 04:58 +0000
          Re: ImageIO/BufferedImage behaving inconsistently from one day to the next. Knute Johnson <nospam@knutejohnson.com> - 2012-06-21 05:58 -0700

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