Picture Compression

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woodchip
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Picture Compression

Post by woodchip »

I got a pic off the new camera and it was something like 9 meg in size. Using the jpeg interchange I could compress it down to 197K. I need to get it to 100K in order to post it to a web site. So how do I do this?
I already tried re-compressing the compressed version but the interchange won't let me do anything more.
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Tetrad
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Post by Tetrad »

... make it smaller?
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fliptw
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Post by fliptw »

I say: get the raw 9 meg file, and mess around with it inside something like photoshop.

you might have to resize it smaller to get under 100k.
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Jeff250
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Post by Jeff250 »

Tetrad wrote:... make it smaller?
MSPaint should do the trick.
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Avder
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Post by Avder »

Try neutering the color depth. Thats how I got my Gir icon down to DBB regulation size. At default its about 20K too big.
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DCrazy
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Post by DCrazy »

Except that yours is a GIF, Vader. Woodchip is using a JPEG. Reducing the color depth will do no good because at the compression level woodchip is apparently using the solid blocks of color will be rendered as muddy murky messes.
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Post by MD-2389 »

Try using the "Save for Web" feature of Photoshop? (CTRL ALT SHIFT S is the keyboard shortcut)

Also, are you reading the filesize in Photoshop or in Windows Explorer? Theres a BIG difference between the two, depending on the level of compression. If you really don't want to ★■◆● with it, get with me on ICQ, AIM, or send it to my gmail account. (md2389@gmail.com Nobody ask for invites because I don't have any yet.) Relevant info is in my profile.
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Avder
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Post by Avder »

Couldnt he drop it down from 24 bit to 16 or 8 tho?
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woodchip
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Post by woodchip »

Thanks for the help. Here's what I did.
I only have a starter photoshop which is worse than useless. With the camera was another software picture publisher by Arcsoft that allowed me to resize from 2100x1150 (size from flash card) down to 1078x 800. Then I cropped it. Then I saved it. Arcsoft does not have a jpeg interchange compression feature so I dug up my freebe Microgrfx software (from my old Matrox G200 set up disk...see why I keep all my old disks), loaded it and used that to jpeg it to the 100kb limit. Result is in the testing zone. Nice bike eh?
Oh and feel free to critique the pic as to composition color etc.
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Kyouryuu
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Post by Kyouryuu »

Correct me if I'm wrong, but JPEG always saves things as 16.7 million colors, so it is irrelevant what the original color depth of the image is? Color depth should affect formats like PNG and GIF, where file size is significantly determined by how many colors are present.

Another suggestion, woodchip, would be to download and try the Gimp 2.0. It's a freeware paint program that has support for dozens of formats and compression options for each. Another option is IrfanView.
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Wolf on Air
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Post by Wolf on Air »

Something to note is that photoshop saves about 20 KB of useless metainfo in addition to non-perfectly optimized huffman tables. Nice way to (mostly losslessly) cram your JPEGs down a bit further is to run "jpegtran -copy none -optimize -progressive" using jpegtran from ImageMagick.
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