OT: image enlargement software

Erk wrote on 1/27/2005, 11:30 PM
Anybody familiar with Imagener software? It's a tool to increase the size/resolution of digital images. They are coming out with a new version that claims to be the "world's first raster to vector technology."

I've been using their previous version ("Enhanced"), and for some images, it does a pretty good job. Perhaps folks more knowledgeable could take a look at the link and see what they think:

http://www.imagener.com/imagenerunl.html

Comments

Chienworks wrote on 1/28/2005, 4:12 AM
Well, they're lying about their claim. We used a rastor to vector program to digitize our old paper drawings nearly 20 years ago when we first started getting into CAD.
B_JM wrote on 1/28/2005, 4:45 AM
i was thinking about the same thing -- raster to vector been around for ages ...

some of the best image enlargement software you can find anywhere is freeware ..
farss wrote on 1/28/2005, 6:13 AM
The idea is interesting, I wonder if anyone has thought to try the technique for upresing video?
Bob.
Laurence wrote on 1/28/2005, 6:42 AM
Not too long ago I auditioned every still uprezzing program I could get my hands on. Photozoom Pro looked the best to my eyes by a longshot.

As far as uprezzing video goes, I've had really good results using the latest version of VirtualDub using the Lancos 3 algorythm. You need to use the deinterlacer to separate the fields before resizing and to recombine them after resizing, but it really works well.
rs170a wrote on 1/28/2005, 6:52 AM
some of the best image enlargement software you can find anywhere is freeware ..

B_JM, any specific software you recommend?

Mike
Jøran Toresen wrote on 1/28/2005, 9:34 AM
Laurence

Three questions concerning VirtualDub.

1. Which filter do you use to deinterlace your video and which settings do you use?
2. Which filter do you use when you resize using the Lancos 3 algorithm? And what are your settings?
3. Which filter do you use to recombine your video and which settings do you use?

Joran,
Norway
Laurence wrote on 1/28/2005, 11:29 AM
I use the native filters that come with latest version of version of VirtualDub version 1.6.

You need to use a chain of three filters:

1: deinterlace filter set to "unfold fields side by side"
2: resize filter set to lancos 3 resize and resizing to a number that is half as high and twice as wide as what you want to end up with.
3: deinterlace filter set to "fold side by side fields together"

If you want a progressive scan image you can add another step:

4: deinterlace filter set to your favorite deinterlace type. (mine is a simple "blend fields")
Laurence wrote on 1/28/2005, 11:38 AM
If you want to change the aspect ratio at the same time, you can crop the input settings of the first filter in the chain. For example, if you crop 30 lines each off the top and bottom of a DV resolution 720 x 480 interlaced clip, unfold to side by side fields, resize with a lancos 3 algorythm to 2560 x 360, fold side by side fields together, deinterlace using the blend fields option, and compress using WMV9 compression, you get a compact HD wmv9 encoded avi file that looks quite good. It's not the crystal clear "looking through a window" look of HDV, but it is a very smooth looking blowup.
Jøran Toresen wrote on 1/28/2005, 12:33 PM
Hello
Do you really mean "half as high and twice as wide as what you want to end up with"? Why? I have a PAL video (720x576). So I should set the width to 1440 and the height to 288 pixels?

Joran,
Norway

B_JM wrote on 1/28/2005, 1:16 PM
virtualdub does one of the best apps around, using the lanczos filter .. even other apps that use this filter didnt fair as well ... that is for 8bit images..
for 10, 16 and floating point i use digital fusion

I work in large format film and do insane up-rezing at times ... plus pull off frames that will be used in ads and banners - uprezing 1080 to 6k -8k is not uncommon ..

key is stepping the up size in smaller steps - using div. of 16 , edge enhancement and smoothing. and dithering -- higher color space than 8 is going to really help also on some material

Laurence wrote on 1/28/2005, 1:23 PM
When you "deinterlace - unfold" your 720x576 image you will end up with a 1440 x 288 image consisting of two half height progressive images displayed side by side. At this point, the "deinterlace - fold" filterwould generate your origin 720 x 576 frame. The idea is to resize the side by side progressive images then recombine the the two sides to make a new interlaced frame.

Thus if you wanted to go from 3:4 aspect 720 x 576 PAL to progressive scan 1280 by 720 HD resolution you would need a chain of 4 filters:

1. Deinterlace unfold fields and crop 72 lines off both the top and the bottom of the image. This will give you an image that is 1440 wide x 216 high.

2. Resize this to 2560 x 360 using the lancos 3 algorythm.

3. Fold the fields back together and you will now have a 16:9 interlaced image that is 1280 by 720.

3. Deinterlace this image using "blend fields" or whatever algorythm you prefer.

VirtualDub also lets you set the compression codec that the new file will be saved as. It is important that you use a format that Windows Media Player understands so that it can play back the resulting file. WMV 9 works really well here. You will have to install the Microsoft wmv 9 codec to do this. I don't remember exactly where to find this, but when you try to configure VirtualDub to use this codec it will tell you that you need it and guide you in getting it.

The advantage of this approach is that as the lancos 3 algorythm is trying to draw lines between points, it doesn't have to deal with the combed interlace lines that would otherwise confuse it. The two fields resize quite nicely when placed side by side instead of on alternating lines,
B_JM wrote on 1/28/2005, 1:37 PM
for large resizing - i suggest to do it in steps - you can stack filters ..

for large format up-scaling, i will often take in between steps into another app for edge detail and dithering and smoothing .

i wrote a detailed explanation of this on this forum a while back ... i work primarly with film, so dont have to worry about de-interlacing, but Laurence's unfold tips are a very good idea. Scaling does not work well on interlaced material ..