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Adobe Bicubic Smoother upsize vs Genuine Fractals

 
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John Navas

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Since: Nov 04, 2007
Posts: 1436



(Msg. 1) Posted: Tue Nov 27, 2007 7:39 pm
Post subject: Adobe Bicubic Smoother upsize vs Genuine Fractals
Archived from groups: rec>photo>digital (more info?)

Here's a comparison of Adobe Bicubic Smoother resizing in current
versions of Photoshop against Genuine Fractals v5. For a large amount of
realistic detail, I started with a 400x400 crop of leaves from my
Panasonic DMC-FZ8, and then upsampled to 200% (565x565), 300% (700x700),
and 400% (810x810), in a single step from the original in each case,
cropping back to 400x400 for inspection. (All images are 100% 1:1
crops.) Final comparison image was saved at JPEG quality 11 in
Photoshop.

<http://img265.imageshack.us/my.php?image=resizingns7.jpg>

200%: I see no real difference

300%: Genuine Fractals may be a tiny bit better, but may also be a tiny
bit harsher, and any difference is too small for me to care about

400%: Genuine Fractals is a bit better, but the difference may not be
visible in a print

Bottom line: I think Adobe Bicubic Smoother is fine for most purposes,
and wouldn't bother with Genuine Fractals except for very large
upsizing.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

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John Navas

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Since: Nov 04, 2007
Posts: 1436



(Msg. 2) Posted: Wed Nov 28, 2007 12:36 pm
Post subject: Bicubic Smoother vs Genuine Fractals vs Alienskin Blowup [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

Here's an updated comparison of Adobe Bicubic Smoother upsizing (in
current versions of Photoshop) versus Genuine Fractals 5.0.3 versus
Alienskin Blowup 1.0.2. For a large amount of realistic detail, I
started with a 400x400 crop of leaves from my Panasonic DMC-FZ8, and
then upsampled to 200% (565x565), 300% (700x700), and 400% (810x810), in
a single step from the original in each case, cropping back to 400x400
for comparison. (All images are 100% 1:1 crops.) Final comparison image
was saved at JPEG quality 10 in Photoshop.
http://img137.imageshack.us/img137/412/resizingtestsxh0.jpg
My take is that Blowup has a somewhat plastic look that increases with
increasing resizing. Genuine Fractals seems to have the most detail in
larger resizing, but to me it looks more like artifacting than real
detail. I personally think Bicubic Smoother is doing the best job
overall.
--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)

 >> Stay informed about: Adobe Bicubic Smoother upsize vs Genuine Fractals 
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Scott W

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Since: Apr 16, 2007
Posts: 607



(Msg. 3) Posted: Wed Nov 28, 2007 12:36 pm
Post subject: Re: Bicubic Smoother vs Genuine Fractals vs Alienskin Blowup [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

John Navas wrote:
> Here's an updated comparison of Adobe Bicubic Smoother upsizing (in
> current versions of Photoshop) versus Genuine Fractals 5.0.3 versus
> Alienskin Blowup 1.0.2. For a large amount of realistic detail, I
> started with a 400x400 crop of leaves from my Panasonic DMC-FZ8, and
> then upsampled to 200% (565x565), 300% (700x700), and 400% (810x810), in
> a single step from the original in each case, cropping back to 400x400
> for comparison. (All images are 100% 1:1 crops.) Final comparison image
> was saved at JPEG quality 10 in Photoshop.
> http://img137.imageshack.us/img137/412/resizingtestsxh0.jpg
> My take is that Blowup has a somewhat plastic look that increases with
> increasing resizing. Genuine Fractals seems to have the most detail in
> larger resizing, but to me it looks more like artifacting than real
> detail. I personally think Bicubic Smoother is doing the best job
> overall.

It took me a while to realize what you are calling 400% is in area not
linear dimensions.

You might want to use a number of images for your source before coming
to any hard conclusions. And image with a mix of low contrast content
mixed with some hard edges would be interesting.

Scott
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John Navas

External


Since: Nov 04, 2007
Posts: 1436



(Msg. 4) Posted: Wed Nov 28, 2007 4:37 pm
Post subject: Re: Bicubic Smoother vs Genuine Fractals vs Alienskin Blowup [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

On Wed, 28 Nov 2007 09:27:17 -1000, Scott W <biphoto.RemoveThis@hotmail.com> wrote
in <474dc11c$0$24288$4c368faf@roadrunner.com>:

>John Navas wrote:
>> Here's an updated comparison of Adobe Bicubic Smoother upsizing (in
>> current versions of Photoshop) versus Genuine Fractals 5.0.3 versus
>> Alienskin Blowup 1.0.2. For a large amount of realistic detail, I
>> started with a 400x400 crop of leaves from my Panasonic DMC-FZ8, and
>> then upsampled to 200% (565x565), 300% (700x700), and 400% (810x810), in
>> a single step from the original in each case, cropping back to 400x400
>> for comparison. (All images are 100% 1:1 crops.) Final comparison image
>> was saved at JPEG quality 10 in Photoshop.
>> http://img137.imageshack.us/img137/412/resizingtestsxh0.jpg
>> My take is that Blowup has a somewhat plastic look that increases with
>> increasing resizing. Genuine Fractals seems to have the most detail in
>> larger resizing, but to me it looks more like artifacting than real
>> detail. I personally think Bicubic Smoother is doing the best job
>> overall.
>
>It took me a while to realize what you are calling 400% is in area not
>linear dimensions.

The percentage is the amount of *image* (re)sizing, correct usage, and
the exact methodology is in what you quoted. Using the percentage for
both dimensions would have been misleading.

>You might want to use a number of images for your source before coming
>to any hard conclusions. And image with a mix of low contrast content
>mixed with some hard edges would be interesting.

I've actually tested lots of different images. I just don't have the
time to present it all here. This particular image seemed most
representative, which is why I used it. Feel free to contribute similar
results for whatever images you think would be interesting additions.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)
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Scott W

External


Since: Apr 16, 2007
Posts: 607



(Msg. 5) Posted: Wed Nov 28, 2007 4:37 pm
Post subject: Re: Bicubic Smoother vs Genuine Fractals vs Alienskin Blowup [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

John Navas wrote:
> On Wed, 28 Nov 2007 09:27:17 -1000, Scott W <biphoto.RemoveThis@hotmail.com> wrote
> in <474dc11c$0$24288$4c368faf@roadrunner.com>:
>
>> John Navas wrote:
>>> Here's an updated comparison of Adobe Bicubic Smoother upsizing (in
>>> current versions of Photoshop) versus Genuine Fractals 5.0.3 versus
>>> Alienskin Blowup 1.0.2. For a large amount of realistic detail, I
>>> started with a 400x400 crop of leaves from my Panasonic DMC-FZ8, and
>>> then upsampled to 200% (565x565), 300% (700x700), and 400% (810x810), in
>>> a single step from the original in each case, cropping back to 400x400
>>> for comparison. (All images are 100% 1:1 crops.) Final comparison image
>>> was saved at JPEG quality 10 in Photoshop.
>>> http://img137.imageshack.us/img137/412/resizingtestsxh0.jpg
>>> My take is that Blowup has a somewhat plastic look that increases with
>>> increasing resizing. Genuine Fractals seems to have the most detail in
>>> larger resizing, but to me it looks more like artifacting than real
>>> detail. I personally think Bicubic Smoother is doing the best job
>>> overall.
>> It took me a while to realize what you are calling 400% is in area not
>> linear dimensions.
>
> The percentage is the amount of *image* (re)sizing, correct usage, and
> the exact methodology is in what you quoted. Using the percentage for
> both dimensions would have been misleading.

When re-sizing Photoshop figures 200% is in both directions, so this can
be taken either way.

>> You might want to use a number of images for your source before coming
>> to any hard conclusions. And image with a mix of low contrast content
>> mixed with some hard edges would be interesting.
>
> I've actually tested lots of different images. I just don't have the
> time to present it all here. This particular image seemed most
> representative, which is why I used it. Feel free to contribute similar
> results for whatever images you think would be interesting additions.

Here is a lot of other methods with more test images.
http://www.americaswonderlands.com/digital_photo_interpolation.htm

Some do a bit better then others, but over all you are far better off
starting with enough pixels.

Some of the methods do well with sharp edges but mess up the eye pretty bad.

Here is a rather extensive paper on Image Interpolation
http://www.math.ucla.edu/~wittman/thesis/Poral2.pdf

It would be interesting to test the best interpolation method against
bicubic starting with a bit more resolution.

My guess is that gains are small.

Scott
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John Navas

External


Since: Nov 04, 2007
Posts: 1436



(Msg. 6) Posted: Wed Nov 28, 2007 6:36 pm
Post subject: PhotoZoom Pro vs Bicubic Smoother vs Genuine Fractals vs Alienskin Blowup [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

My comparison expanded to include PhotoZoom Pro, all at 400% (both x and
y doubled). My own take is that Bicubic Smoother has a bit more detail
and a bit less blurring than PhotoZoom Pro.
Adobe Bicubic Smoother (PSE6):
<http://img86.imageshack.us/my.php?image=4810bicubicsmoothersa9.png>
PhotoZoom Pro (x-spline-xl):
<http://img81.imageshack.us/my.php?image=resizingtestsxh00mw2.png>
Genuine Fractals (5.0.3):
<http://img81.imageshack.us/my.php?image=7810genuinefractalshy0.png>
Alienskin Blowup (1.0.2):
<http://img128.imageshack.us/my.php?image=a810blowupho1.png>
--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)
--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)
 >> Stay informed about: Adobe Bicubic Smoother upsize vs Genuine Fractals 
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John Navas

External


Since: Nov 04, 2007
Posts: 1436



(Msg. 7) Posted: Wed Nov 28, 2007 9:35 pm
Post subject: Re: Bicubic Smoother vs Genuine Fractals vs Alienskin Blowup [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

On Wed, 28 Nov 2007 12:50:25 -1000, Scott W <biphoto DeleteThis @hotmail.com> wrote
in <474df0ba$0$2339$4c368faf@roadrunner.com>:

>John Navas wrote:

>> I've actually tested lots of different images. I just don't have the
>> time to present it all here. This particular image seemed most
>> representative, which is why I used it. Feel free to contribute similar
>> results for whatever images you think would be interesting additions.
>
>Here is a lot of other methods with more test images.
>http://www.americaswonderlands.com/digital_photo_interpolation.htm
>Some do a bit better then others, but over all you are far better off
>starting with enough pixels.
>Some of the methods do well with sharp edges but mess up the eye pretty bad.
>Here is a rather extensive paper on Image Interpolation
>http://www.math.ucla.edu/~wittman/thesis/Poral2.pdf
>It would be interesting to test the best interpolation method against
>bicubic starting with a bit more resolution.
>My guess is that gains are small.

Yep. Here are some good additional resources:
<http://www.general-cathexis.com/interpolation.html>
<http://www.ronbigelow.com/articles/interpolation/interpolation.htm>

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)
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Bill Tuthill

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Since: Sep 07, 2006
Posts: 243



(Msg. 8) Posted: Wed Nov 28, 2007 10:52 pm
Post subject: Re: Adobe Bicubic Smoother upsize vs Genuine Fractals [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

John Navas wrote:
> Here's a comparison of Adobe Bicubic Smoother resizing in current
> versions of Photoshop against Genuine Fractals v5...
>
> http://img265.imageshack.us/my.php?image=resizingns7.jpg
>
> 300%: Genuine Fractals may be a tiny bit better, but may also be a tiny
> bit harsher, and any difference is too small for me to care about
> ...
> Bottom line: I think Adobe Bicubic Smoother is fine for most purposes,
> and wouldn't bother with Genuine Fractals except for very large upsizing.

Nice work, but it's too bad you didn't compare Adobe Bicubic Smoother
to a really good upsampling algorithm such as that in Qimage,
or data-dependent Lanczos filters in SAR from general-cathexis.com.
 >> Stay informed about: Adobe Bicubic Smoother upsize vs Genuine Fractals 
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trent kingston

External


Since: Nov 29, 2007
Posts: 1



(Msg. 9) Posted: Thu Nov 29, 2007 2:03 am
Post subject: Re: Adobe Bicubic Smoother upsize vs Genuine Fractals [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

On Wed, 28 Nov 2007 22:52:53 -0800, Bill Tuthill
<ccreekin.TakeThisOut@yahoo.com> wrote:

>John Navas wrote:
>> Here's a comparison of Adobe Bicubic Smoother resizing in current
>> versions of Photoshop against Genuine Fractals v5...
>>
>> http://img265.imageshack.us/my.php?image=resizingns7.jpg
>>
>> 300%: Genuine Fractals may be a tiny bit better, but may also be a tiny
>> bit harsher, and any difference is too small for me to care about
>> ...
>> Bottom line: I think Adobe Bicubic Smoother is fine for most purposes,
>> and wouldn't bother with Genuine Fractals except for very large upsizing.
>
>Nice work, but it's too bad you didn't compare Adobe Bicubic Smoother
>to a really good upsampling algorithm such as that in Qimage,
>or data-dependent Lanczos filters in SAR from general-cathexis.com.

Keeping in mind too that extrapolation is different than
interpolation. Results found upsizing are not applicable to
downsizing, and vice-versa. Bicubic usually makes a mess of
things in downsizing. Lanczos to the rescue.
 >> Stay informed about: Adobe Bicubic Smoother upsize vs Genuine Fractals 
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rphunter

External


Since: Jun 06, 2004
Posts: 3286



(Msg. 10) Posted: Thu Nov 29, 2007 4:10 am
Post subject: Re: Bicubic Smoother vs Genuine Fractals vs Alienskin Blowup [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

Scott W wrote:
> John Navas wrote:
>> Here's an updated comparison of Adobe Bicubic Smoother upsizing (in
>> current versions of Photoshop) versus Genuine Fractals 5.0.3 versus
>> Alienskin Blowup 1.0.2. For a large amount of realistic detail, I
>> started with a 400x400 crop of leaves from my Panasonic DMC-FZ8, and
>> then upsampled to 200% (565x565), 300% (700x700), and 400% (810x810), in
>> a single step from the original in each case, cropping back to 400x400
>> for comparison. (All images are 100% 1:1 crops.) Final comparison image
>> was saved at JPEG quality 10 in Photoshop.
>> http://img137.imageshack.us/img137/412/resizingtestsxh0.jpg
>> My take is that Blowup has a somewhat plastic look that increases with
>> increasing resizing. Genuine Fractals seems to have the most detail in
>> larger resizing, but to me it looks more like artifacting than real
>> detail. I personally think Bicubic Smoother is doing the best job
>> overall.
>
> It took me a while to realize what you are calling 400% is in area not
> linear dimensions.
>
> You might want to use a number of images for your source before coming
> to any hard conclusions. And image with a mix of low contrast content
> mixed with some hard edges would be interesting.
>
> Scott

I agree. I suspect some methods would do better with one type of image.
For instance, Genuine Fractals would probably do better with scenes
like trees, grass, etc. Still, they all look pretty good in the
examples, although at 400% the GF image began to show some noise.
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John Navas

External


Since: Nov 04, 2007
Posts: 1436



(Msg. 11) Posted: Thu Nov 29, 2007 4:43 pm
Post subject: Re: Adobe Bicubic Smoother upsize vs Genuine Fractals [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

On Thu, 29 Nov 2007 02:03:36 -0600, trent kingston
<tkingston0002 DeleteThis @gmail.com> wrote in
<mcssk3d65dsie308ijtqir23sf3f5s7k9d DeleteThis @4ax.com>:

>On Wed, 28 Nov 2007 22:52:53 -0800, Bill Tuthill
><ccreekin DeleteThis @yahoo.com> wrote:
>
>>John Navas wrote:
>>> Here's a comparison of Adobe Bicubic Smoother resizing in current
>>> versions of Photoshop against Genuine Fractals v5...
>>>
>>> http://img265.imageshack.us/my.php?image=resizingns7.jpg
>>>
>>> 300%: Genuine Fractals may be a tiny bit better, but may also be a tiny
>>> bit harsher, and any difference is too small for me to care about
>>> ...
>>> Bottom line: I think Adobe Bicubic Smoother is fine for most purposes,
>>> and wouldn't bother with Genuine Fractals except for very large upsizing.
>>
>>Nice work, but it's too bad you didn't compare Adobe Bicubic Smoother
>>to a really good upsampling algorithm such as that in Qimage,
>>or data-dependent Lanczos filters in SAR from general-cathexis.com.

Thanks. I was sticking to readily-available plugins for Photoshop.

>Keeping in mind too that extrapolation is different than
>interpolation. Results found upsizing are not applicable to
>downsizing, and vice-versa. Bicubic usually makes a mess of
>things in downsizing. Lanczos to the rescue.

YMMV: I've gotten good downsizing results from Bicubic Sharper.

--
Best regards,
John Navas
Panasonic DMC-FZ8 (and several others)
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Scott W

External


Since: Apr 16, 2007
Posts: 607



(Msg. 12) Posted: Thu Nov 29, 2007 4:43 pm
Post subject: Re: Adobe Bicubic Smoother upsize vs Genuine Fractals [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

John Navas wrote:
> On Thu, 29 Nov 2007 02:03:36 -0600, trent kingston
> <tkingston0002.TakeThisOut@gmail.com> wrote in
> <mcssk3d65dsie308ijtqir23sf3f5s7k9d.TakeThisOut@4ax.com>:
>
>> On Wed, 28 Nov 2007 22:52:53 -0800, Bill Tuthill
>> <ccreekin.TakeThisOut@yahoo.com> wrote:
>>
>>> John Navas wrote:
>>>> Here's a comparison of Adobe Bicubic Smoother resizing in current
>>>> versions of Photoshop against Genuine Fractals v5...
>>>>
>>>> http://img265.imageshack.us/my.php?image=resizingns7.jpg
>>>>
>>>> 300%: Genuine Fractals may be a tiny bit better, but may also be a tiny
>>>> bit harsher, and any difference is too small for me to care about
>>>> ...
>>>> Bottom line: I think Adobe Bicubic Smoother is fine for most purposes,
>>>> and wouldn't bother with Genuine Fractals except for very large upsizing.
>>> Nice work, but it's too bad you didn't compare Adobe Bicubic Smoother
>>> to a really good upsampling algorithm such as that in Qimage,
>>> or data-dependent Lanczos filters in SAR from general-cathexis.com.
>
> Thanks. I was sticking to readily-available plugins for Photoshop.
>
>> Keeping in mind too that extrapolation is different than
>> interpolation. Results found upsizing are not applicable to
>> downsizing, and vice-versa. Bicubic usually makes a mess of
>> things in downsizing. Lanczos to the rescue.
>
> YMMV: I've gotten good downsizing results from Bicubic Sharper.
>
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Scott W

External


Since: Apr 16, 2007
Posts: 607



(Msg. 13) Posted: Thu Nov 29, 2007 4:43 pm
Post subject: Re: Adobe Bicubic Smoother upsize vs Genuine Fractals [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

John Navas wrote:
> On Thu, 29 Nov 2007 02:03:36 -0600, trent kingston
> <tkingston0002 RemoveThis @gmail.com> wrote in
> <mcssk3d65dsie308ijtqir23sf3f5s7k9d RemoveThis @4ax.com>:
>
>> On Wed, 28 Nov 2007 22:52:53 -0800, Bill Tuthill
>> <ccreekin RemoveThis @yahoo.com> wrote:
>>
>>> John Navas wrote:
>>>> Here's a comparison of Adobe Bicubic Smoother resizing in current
>>>> versions of Photoshop against Genuine Fractals v5...
>>>>
>>>> http://img265.imageshack.us/my.php?image=resizingns7.jpg
>>>>
>>>> 300%: Genuine Fractals may be a tiny bit better, but may also be a tiny
>>>> bit harsher, and any difference is too small for me to care about
>>>> ...
>>>> Bottom line: I think Adobe Bicubic Smoother is fine for most purposes,
>>>> and wouldn't bother with Genuine Fractals except for very large upsizing.
>>> Nice work, but it's too bad you didn't compare Adobe Bicubic Smoother
>>> to a really good upsampling algorithm such as that in Qimage,
>>> or data-dependent Lanczos filters in SAR from general-cathexis.com.
>
> Thanks. I was sticking to readily-available plugins for Photoshop.
>
>> Keeping in mind too that extrapolation is different than
>> interpolation. Results found upsizing are not applicable to
>> downsizing, and vice-versa. Bicubic usually makes a mess of
>> things in downsizing. Lanczos to the rescue.
>
> YMMV: I've gotten good downsizing results from Bicubic Sharper.

I get good results from Bicubic as well, down sample and then use a bit
of USM.

I seem to have more problems with Lanczos, using IrfanView.

Here are my test images, the 1000 x 1000 image was my starting image, I
down sided to 345 x 345 pixels in both cases.

http://www.pbase.com/konascott/downsampling

If anyone want to try their hand at down sampling the 1000 x 1000 image
free free to use it.

Scott
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davidjl

External


Since: Jun 03, 2004
Posts: 1804



(Msg. 14) Posted: Thu Nov 29, 2007 7:46 pm
Post subject: Re: Adobe Bicubic Smoother upsize vs Genuine Fractals [Login to view extended thread Info.]
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"Scott W" <biphoto.DeleteThis@hotmail.com> wrote:
>
> I seem to have more problems with Lanczos, using IrfanView.
>
> Here are my test images, the 1000 x 1000 image was my starting image, I
> down sided to 345 x 345 pixels in both cases.
>
> http://www.pbase.com/konascott/downsampling
>
> If anyone want to try their hand at down sampling the 1000 x 1000 image
> free free to use it.

It was more fun with the maximally disoptimal bar pattern....

David J. Littleboy
Tokyo, Japan
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Scott W

External


Since: Apr 16, 2007
Posts: 607



(Msg. 15) Posted: Thu Nov 29, 2007 7:47 pm
Post subject: Re: Adobe Bicubic Smoother upsize vs Genuine Fractals [Login to view extended thread Info.]
Archived from groups: per prev. post (more info?)

David J. Littleboy wrote:
> "Scott W" <biphoto.DeleteThis@hotmail.com> wrote:
>> I seem to have more problems with Lanczos, using IrfanView.
>>
>> Here are my test images, the 1000 x 1000 image was my starting image, I
>> down sided to 345 x 345 pixels in both cases.
>>
>> http://www.pbase.com/konascott/downsampling
>>
>> If anyone want to try their hand at down sampling the 1000 x 1000 image
>> free free to use it.
>
> It was more fun with the maximally disoptimal bar pattern....
>
> David J. Littleboy
> Tokyo, Japan
>
>
Yeah, but people got hung up on that and it is not very real world.

But anyone who wants to play with that one here it is.
http://www.pbase.com/konascott/image/69543104/original
The challenge is to down sample by a factor of 4, linear.
The bar patter should disappear if there is no aliasing, but you can't
get a sharp looking down sized image without some aliasing.

The only method that I have run across that is way bad is nearest
neighbor, which is bad beyond believe.

Scott
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