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Enlarging raster images?

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emkemner

Technical User
Oct 6, 2003
59
US
Quick question. Are there any programs out there that will either, 1) take a raster image and convert it to a vector image. or 2) increase the size of a raster file without pixlating the hell out of it.
 
1) NO
2) NO

Open up illustrator and outline it like everyone else does.

There might be some ways to speed it up or programs but ive never come across any method that beat a good ol outlining in illustrator.

zzzzzz
 
As to part one of your question; actually there are a hell of a lot of Raster>Vector conversion programs around, Streamline and Flash, Panopticum Vectorizer, to name a few.

Moe: It could have been a real ugly situation, but luckily I managed to shoot him in the spine.
 
But let's be realistic... most of those raster to vector programs create so many nodes that the time taken to delete the excess and otherwise clean up, you might as well trace it yourself from scratch. However, it depends a lot on the content of the original as to how well the conversion goes.
 
Outlineing it wont work, Its a photograph not a graphic. I need to put a photo on a billboard. The current photo size is 5 inches by 3.5 inches at 72 dpi and it needs to be printed at 6 foot by 4.75 foot. If it cant be done how do people get crisp looking pictures to 14 foot on highway billboards? Theres got to be a way finding it is the problem.
 
>>The current photo size is 5 inches by 3.5 inches at 72 dpi and it needs to be printed at 6 foot by 4.75 foot.<<

Ha ha. You've GOT to be joking!!!

It is simply not possible to vectorise a photo - and have it still look like a photo - any more thn you can reasonably expect 360 (5x72) pixels x 252 (3.5x72) pixels to look anything other than c**p at 6' x 4.75'. I mean, they're not even in the same proportion, so one side or another will have to be cropped, losing even more pixels. But let's say that you could keep all the pixels. At 6' wide (72") each pixel would be 1" square. Think it would be obvious?

Most billboards DO have visible pixels up close, but I think the minimum acceptable resolution is around 50-60 dpi at 100% size. That is, across the 6' you need 72" x 55dpi = 3960 px. You've got less than a tenth of that.

3960 px across is equivalent to an image 13.2" across @ 300 dpi, a not unreasonable size/resolution for a professional photo.

>>how do people get crisp looking pictures on highway billboards? <<

They get good quality images to start with, and remember that since billboards are not designed to be viewed up close, final resolution can be quite low (50-60dpi). But NOT in the original image!!

 
It seems a bit difficult to get exact data on resolution preferred by billboard printers. But one site
had this to say:

For our 300 DPI output vinyl banner printing, we need a raster file resolution of 72 DPI at actual size. For instance, a 6' x 20' vinyl print could be set up at 6" x 20" @ 864 DPI, which is equivalent to 6' x 20' @ 72 DPI.

For our 70 DPI printed billboards, we need a raster file resolution of 25 DPI at actual size. For instance, a 14' x 48' billboard could be set up at 14" x 48" @ 300 DPI, which is equivalent to 14' x 48' @ 25 DPI.

These resolutions work well, but you may add more resolution if you wish. Our general rule of thumb for resolution is the more resolution you put into the system, the more you will get out of the system.

Of course, you need not worry about the resolution for vector graphics from programs such as Adobe Illustrator. It is wise to keep in mind that the DPI suggestions above still apply to raster images placed in vectorized graphics.

This PDF also has some artwork specs for billboards:


There apeared to be some variation for resolution required, but most seemed to be in the region I quoted in the earlier post, although some were lower, such as 20-30 dpi. Most recommended setting up the file in the ratio of 0.5" or 1" for each 1' of final size. And using 300 dpi images means that the final resolution will be 50 dpi or 25dpi respectively.
 
I worked in large format printing for about 10 years, and I can only echo what Eggles has already posted. The file you have is too small for what you need. The exact resolution you need depends on who's printing it, so check with them.

However, all is not lost. If you accept that your existing image will not look good, then try changing it's appearance. One successful example I've seen and used involves enlarging the image using Image Size, then applying an effect, such as Filter > Noise > Median, to hide the fact that it has been enlarged. It won't look like you originally wanted it too, but it will look like a sharp filtered image, rather than a badly enlarged photo. Experiment and see what filters work for you.
 
Well i spent hours searching the web but i found something that works and works well. The program is called genuine fractiles. It basicaly increases the pixle count and image size with almost no distortion. I'm guessing its rather new since information on it was so difficult to find. Hopefully this helps someone other than me out.

heres the link.
 
Genuine FRACTALS is well known in this forum(you could also have tried Photozoom, SmartScale, Xfile and more), but none of them will increase your pics to the size you want without loss of quality. Nothing will.

Your best bet would be to do as blueark suggests, use the resized image to create a new image.

Moe: It could have been a real ugly situation, but luckily I managed to shoot him in the spine.
 
We've all heard of Genuine Fractals, and although it can create pixels (by averaging the colours of surrounding pixles and thus increasing resolution in small increments), you sure aren't going to get a clear picture on the sort of scale you need.

What I want to know is, how can someone who has no concept of resolution, and refuses to accept the advice given on this forum, gets to do the job you have been asked to do?
 
I have been doing this work for years and have an excelent understanding of resolution and have a nikon d100 that takes 300dpi pics at 3008 pi X 2000 pi resolution. I however dont have the means to reshoot the picture i was asked to place on this particular bill board. I take the advise of the users of this forum very seriously and i know i dont know everything. The question I had was not answered in this forum and was answered in another forum by telling me to check out genuine fractals. I figured i would share that with this forum..... if I was wrong in thinking that you all didnt know about it then my bad but I felt since no one here offered the solution i would share. And I know it will not increase the size of the pic i have to what i wanted it to but it did increase it enough to be veiwed from a distance and still look good.
I dont come on this message board to put people down and i dont expect to be put down. I have an excelent concept of resolution.... Obviuosly some people have no concept of new technology that can and will be created, i was simply asking if it has been created yet or not.


Just because something can not be done at the time does not me it never will be able to be done.
 
Emkemner, I have read all the replies to your original question, and it seems to me that we have all tried to advise you to the best of our ability.

If you had asked 'How do I enlarge images?' We probably would have mentioned the various methods and Progs that would help you to do this.

However, the question you actually asked (after a few posts)was answered fully - You can't enlarge small images to that size with any software yet in existence.

Saying that no one answered your question is unfair and untrue. Sorry you feel slighted, but I don't see any reason for you to feel so.

PS; The mention of the GF plugin WAS appreciated, even if it was known.
Also a tip for you would be to search the previous threads about enlarging images - this is a topic that comes up at least once a month; you will find plenty of different methods explained for enlarging, not just the use of plugins.

Moe: It could have been a real ugly situation, but luckily I managed to shoot him in the spine.
 
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