Search found 25 matches

by atariZen
2019-05-23T04:13:31-07:00
Forum: Users
Topic: searching for presence of a unique color in security cams to catch a bicycle thief
Replies: 1
Views: 3242

searching for presence of a unique color in security cams to catch a bicycle thief

If a stolen bicycle has a custom color that is so unique that no other object would likely appear on the surveillance cameras in the city with the same color, could IM be used to find images where the bike appears? Suppose we neglect the fact that the frame is a certain shape, and look simply for im...
by atariZen
2018-03-05T11:51:07-07:00
Forum: Users
Topic: resolution of PDF files forced to 72x72 even when -density is used
Replies: 4
Views: 11153

Re: resolution of PDF files forced to 72x72 even when -density is used

Thanks snibgo, you've cleared some things up. I'm happy to hear about "pdfimages -list".. that's quite useful. I now have a working solution that's verifiable. But I will mention some annoyances to warn others, perhaps to also serve as a note to developers: * ImageMagick alters the resolut...
by atariZen
2018-03-04T08:35:50-07:00
Forum: Users
Topic: resolution of PDF files forced to 72x72 even when -density is used
Replies: 4
Views: 11153

resolution of PDF files forced to 72x72 even when -density is used

I have a 600 dpi PBM file, and I simply want to wrap in a PDF with no changes. I would expect this to work, but it gets downsampled to 72x72: $ convert source.pbm target.pdf $ identify -verbose target.pdf | grep -i reso Resolution: 72x72 So I also tried to brute-force it to maintain the 600 dpi: $ c...
by atariZen
2018-02-13T12:09:48-07:00
Forum: Users
Topic: the -size and -resize options are ignored if the output is a fax filetype
Replies: 1
Views: 2035

the -size and -resize options are ignored if the output is a fax filetype

The source file has geometry 2592x1944+0+0 $ convert color_source.jpg -threshold 30% -rotate 90 -size 1734x2156 output.fax $ identify -verbose output.fax | grep geom Page geometry: 2592x2592+0+0 Imagemagic does the wrong thing when I omit the "-size" parameter. It should produce a fax-conf...
by atariZen
2018-02-10T09:27:39-07:00
Forum: Users
Topic: preparing a document for a FAX service (e.g. j2)
Replies: 1
Views: 3439

Re: preparing a document for a FAX service (e.g. j2)

For the record, apparently this is the answer, assuming the source is a vector PDF, and we're targeting the medium (fine) fax standard: $ pdf2djvu -o vector.djvu vector.pdf $ ddjvu -mode=black -format=tiff -aspect=no -size=1734x2156 vector.djvu raster.tiff $ convert raster.tiff raster.fax $ fax2tiff...
by atariZen
2018-02-10T07:07:23-07:00
Forum: IMagick
Topic: Making a colorful pdf fax-friendly
Replies: 7
Views: 17981

Re: Making a colorful pdf fax-friendly

Is that PERL? I can't read it. Would someone please post the answer in commandline format?

Thanks!
by atariZen
2018-02-10T06:21:59-07:00
Forum: Users
Topic: preparing a document for a FAX service (e.g. j2)
Replies: 1
Views: 3439

preparing a document for a FAX service (e.g. j2)

Fax services like j2 can accept documents in any format regardless of how high the quality is, and it gets converted to fax quality before sending. The problem is that the sender has no idea what documents look like on the receiving end. The sender should convert the doc to fax quality so they can s...
by atariZen
2016-05-29T00:55:34-07:00
Forum: Users
Topic: Removal lines vertical?
Replies: 15
Views: 15204

Re: Removal lines vertical?

Why should we assume the actual intent is honorable? As snibgo has said, there are plenty of available resources out there that can be Googled. The answer to your own question is right there in the next statement. Malicious hackers do opsec and they also social engineer. They're far more sophistica...
by atariZen
2016-05-28T23:57:59-07:00
Forum: Users
Topic: Removal lines vertical?
Replies: 15
Views: 15204

Re: Removal lines vertical?

You have no idea if the OP is defeating his own captcha, or someone else's. Even if that were true, it would make no difference. I won't help either side. When you said "I won't assist when I know I disapprove of the purpose," it was ambiguous. I thought you meant to disapprove of the pur...
by atariZen
2016-05-27T23:08:53-07:00
Forum: Users
Topic: Removal lines vertical?
Replies: 15
Views: 15204

Re: Removal lines vertical?

Even if I thought the OP had honourable intentions, Which should be the assumption here. I wouldn't help for reasons I've explained a few times. I won't contribute to the captcha arms race. You've unwittingly taken a stance against humanity. The status quo is a loss for humans. Machines are putting...
by atariZen
2016-05-26T14:02:40-07:00
Forum: Users
Topic: Removal lines vertical?
Replies: 15
Views: 15204

Re: Removal lines vertical?

It's clear you're approaching this from an image processing background, when the matter is really infosec-centric. When it comes to security, tools can be used for good and for evil, and attacks on tools can also be done for good for for evil. You don't get to choose whether good or evil is in play ...
by atariZen
2016-05-21T05:33:24-07:00
Forum: Users
Topic: Removal lines vertical?
Replies: 15
Views: 15204

Re: Removal lines vertical?

I would help if I knew the answer. Captchas are unethical. It's wrong to put humans to work for machines -- should be the other way around. Captcha solving is no work for a human. And it fails the objective it was meant for. Abusers/spammers are hiring Indian labor to solve captchas for $0.01 per ca...
by atariZen
2016-05-21T04:56:40-07:00
Forum: Users
Topic: threshold filter makes text blocky
Replies: 1
Views: 3173

threshold filter makes text blocky

I have a receipt that was scanned at 600dpi (because it has fine print). It looks good, until I try to bi-level it like this: convert -density 900 -threshold 60% -type bilevel receipt.png show: At first I did not use the "-density 900" option, but I tried adding that to improve the quality...
by atariZen
2016-05-21T04:26:43-07:00
Forum: Users
Topic: OCR a scan of a faded microfiche
Replies: 4
Views: 5817

Re: OCR a scan of a faded microfiche

Please don't use tinyurl. I cannot follow any of your links because tinyurl blocks Tor.

Anyway, without being able to see your links, I'll blindly suggest a tool called "unpaper". When I have to OCR a document, I use imagemagick in combination with unpaper.
by atariZen
2016-02-15T00:07:11-07:00
Forum: Users
Topic: How to convert large PDF with limit resources
Replies: 13
Views: 18670

Re: How to convert large PDF with limit resources

The PDF files are vector PDFs. Do you mean that we convert the PDFs to Djvu first and then convert the Djvu to image files? Since you're starting with vector PDFs, and must have non-djvu images in the end, I don't think my suggestions will help much. I would only use the lossy djvu format as a midd...