jpeg compression

You can do that with paint, with the shrink/stretch function, but you have to calculate the percentage. Also the B/W conversion is faulty in paint. I use the free screen capture program 20/20

Hi All,

I want to take a simple JPEG file on a PC and compress it say in to 320x240 B&W file.

What steps do I need to take?

Where can I get the JPEG std file format?

What challengers do you think I need to meet?

Regards Joseph

Same here, I have Photoshop, but use Irfanview 95% of the time for light conversion work (also batch conversion!)

Or, you can use a subset of XNVIEW which is NCONVERT on the same site. Nconvert is a command line converter, perfect for batch jobs/scripts and calling from other programs. Cost: free. Works on most common operating systems.

Since nconvert is hard to figure out, here is a starter for you: nconvert -grey 256 -resize 320 240 -out jpeg -o OutName.jpg InName.jpg

You many want to set the compression level (-q) as the default is best quality.

=== Mark

The GIMP. Really good but hell on wheels to get to grips with at first. It's cheap too, like in freeware.

While you're there have a gander at the docs and tuts, you'll need them.

- YD.

If you want to do it yourself out of curiosity, I'd start by looking at jpeg-6b from IJG.

You can get it here: ftp://ftp.uu.net/graphics/jpeg/

It compiles in windows and unix/linux/etc.

If you want to implement it yourself, it's quite complex. I'd start with reading the docs and looking around jpeg-6b. btw, most JPEGs you get are in "JFIF" format.

--buddy

If you have a not-too recent copy of Microsoft Office (up to Office XP but not 2003), there's a program called Microsoft Photo Editor that comes with it that does a dandy job of resizing image (including JPG) files, among other things.

Norm