Improving low resolution images downloaded from some librari

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Piupianissimo
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Re: Improving low resolution images downloaded from some librari

Post by Piupianissimo »

coulonnus wrote:...but it is more than 10 times bigger!
Is this a complaint?
Was my explanation of what I do not good enough?
I try it again:
1. resizing should be done with a Lanczos filter and, if possible, on the original color or grayscale picture (that seems to work)
and now:
2. after resizing the color data can be converted to monocrome
3. save the monocrome picture as CCITT Fax-4 compressed TIFF
Was my explanation lacking this information???
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Re: Improving low resolution images downloaded from some librari

Post by coulonnus »

Piupianissimo wrote:
coulonnus wrote:...but it is more than 10 times bigger!
Is this a complaint?
Sorry, it was a complaint about what I obtain here with Imagemagick.
Piupianissimo wrote:Was my explanation of what I do not good enough?[...]
I'll try IrfanView when I am less busy with scanning and typesetting!
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Re: Improving low resolution images downloaded from some librari

Post by coulonnus »

Piupianissimo wrote:I don't use ImageMagic but IrfanView, but whatever software you use the resizing should be done with a Lanczos filter and, if possible, on the original color or grayscale picture.[...]
I found some way to obtain a reasonable pdf size: I make the Lanczos filter with Imagemagick, but afterwards I do the conversion to pdf without Imagemagick.

But I think the initial images you have converted in your Liszt examples were not that bad, compared to those I had in mind. I'll provide you the URLs if you are ready for the challenge.
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Re: Improving low resolution images downloaded from some librari

Post by Piupianissimo »

coulonnus wrote:But I think the initial images you have converted in your Liszt examples were not that bad, compared to those I had in mind. I'll provide you the URLs if you are ready for the challenge.
OK, perhaps a bit late but I am ready!
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Re: Improving low resolution images downloaded from some librari

Post by coulonnus »

="Piupianissimo"]OK, perhaps a bit late but I am ready!
I was out of town too!

http://levysheetmusic.mse.jhu.edu/levy-search.html Make a search with 'Schubert'
and 'parisiennes' in the search fields.
There is already a decent .pdf on the site, but starting from the .jpg of page 2, can you provide a filtering that cleans the background and does not darken the gap between the double-bar lines?

http://www.lib.unc.edu/music/eam/viewer ... s=ns1_14p4

This one has dark areas near the binding.
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