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I know TIFF and BMP do and PNG doesn't. I'm planning to use this file format to store images that in turn will display on a web page via normal directly. I don't plan to alter them with filters on the client side.

What will work for this scenario?

https://en.wikipedia.org/wiki/Group_4_compression This link says that there are many standard and proprietary image formats that support storing these kind of images but doesn't say which exactly.

unom
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    I think PNG does, actually. GIF as well. That is, PNG and GIF will support black&white images, and will support choosing a palette with just two colors, and thus storing the images in a smaller format. I don't know whether they use the actual group 4 compression, but I can't really tell if (and why) this would be important. There may be many proprietary formats, but those won't be supported by web browsers. – GolezTrol Feb 17 '15 at 19:36
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    Why wouldn't tiff, bmp, png support storing binary images ( cf. bmp 1bpp, png grayscale, 1 channel, 1bpc; tiff bilevel ) ? they all come with lossless compression, which is the way to go in binary images regardless of the image format chosen. – collapsar Feb 17 '15 at 19:41
  • I was under the impression that some had this limitation. Tried PNG from Photoshop once, and true I had to convert to Indexed color first. TIFF had a 1 bit option and I thought they weren't equivalent. Maybe I need to look deeper. Will the formats enumerated by you work in Web Browsers with those settings? @collapsar – unom Feb 17 '15 at 20:02
  • Just try it. For best support in web browsers choose png. Btw, itmay not be crucial to store the fax images in a 1-bit format. Store them in a n-bit format and use exactly 2 values and you'll be fine. The incurred overhead in file size is reduced very well by the common compression methods and probably wouldn't matter in the first place unless you plan to deliver data to the client in bulk amounts. NB: Wrt programmatic image processing, consider the [ImageMagick](http://www.imagemagick.org/) library. It's free, available for each major Os and has bindings for many programming languages. – collapsar Feb 17 '15 at 20:15

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PNG certainly supports 1bit B/W images, either as gray or as indexed.

If what you want is some image format that is standard for web pages and that uses internally the same compression algorithm as CCITT Group 4 compression, then, no, you are out of luck. But why would you want that?

leonbloy
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  • Edited out the Group-4 thing, it's not really an issue. I was under the impression that some had this limitation. Tried PNG from Photoshop once, and true I had to convert to Indexed color first. TIFF had a 1 bit option and I thought they weren't equivalent. Maybe I need to look deeper. – unom Feb 17 '15 at 20:03