It may not reduce noise, but Norman Koren says it does not alias.
Noise would be reduced through averaging, but the amount may not
be that visible as it goes as the square root of size. However, down
sampling *has* to do anti-alias or it is a very bad down sample function
and would create all sorts of problems with image resizing.
Wayne
At 12:13 PM 3/15/2009, you wrote:
>I remember I have seen someone mentioned here that resize does not reduce
>noise, I'm not sure if it is true. I did try to resize the image and see no
>reduction of grain, could you tell me how you do it?
>
>C.H.Ling
>
>----- Original Message -----
>From: "Chuck Norcutt"
>
>> Well, I thought I was at double or more since since the image resolution
>> was probably 500 ppi or less. But I didn't know about the film grain
>> impact. Anyhow, since the image is already scanned at 4000 ppi it
>> should only require downsizing and not rescanning. But my little
>> experiment did show that grain was almost invisible when downsized to
>> 31%... getting close to my 1000-1200 ppi... at least as final resolution.
>>
>> Chuck Norcutt
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