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RJ Emery · 09-20-2006, 12:35 PM

On my W98 system, I have a very large (3 MB) JPEG file. The image is True Gray (256 shades). I thought to cut down its size, I could decrease the number of colors and make it a black and white file (1 bit instead of 8 bits per pixel). To my surprise, the resulting file was always larger by a substantial amount. The image itself is an ink drawing of a map, a prime candidate for making it b&w.

I used Paint Shop Pro version 7 and IrfanView 3.80 to attempt the reduction.

1) Should not a conversion from 256 colors to 2 colors result in a smaller JPEG file?

2) How might I do it using PSP7 or IrfanView?

3) What freeware tools (for W98) would be available to effect such a conversion with a corresponding reduction in file size?

09-20-2006, 12:35 PM	#1
RJ Emery Member Join Date: Mar 2005 Posts: 239	Black and White JPEG Files On my W98 system, I have a very large (3 MB) JPEG file. The image is True Gray (256 shades). I thought to cut down its size, I could decrease the number of colors and make it a black and white file (1 bit instead of 8 bits per pixel). To my surprise, the resulting file was always larger by a substantial amount. The image itself is an ink drawing of a map, a prime candidate for making it b&w. I used Paint Shop Pro version 7 and IrfanView 3.80 to attempt the reduction. 1) Should not a conversion from 256 colors to 2 colors result in a smaller JPEG file? 2) How might I do it using PSP7 or IrfanView? 3) What freeware tools (for W98) would be available to effect such a conversion with a corresponding reduction in file size? __________________ RJ Emery, Eastern USA WordPerfect 8 User on XP Pro SP3 System OCR ScanSoft PaperPort SE v9 on Brother MFC-8840DN Printer/Scanner/Fax

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