AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

1999.05.17 01:34 "CCITT compressing without writing a file.", by Kevin D. Quitt
1999.05.17 17:04 "Re: CCITT compressing without writing a file.", by Tim McNerney
1999.05.17 17:41 "Re: CCITT compressing without writing a file.", by Eric Shapiro

1999.05.17 17:04 "Re: CCITT compressing without writing a file.", by Tim McNerney

I am currently processing images. They arrive with various types of compression and various bit depths. I reduce them to single-bit-per-pixel, and want to compress them with Group IV CCITT. Currently, I am doing this by writing a new TIFF file, then reading it back in to get the compressed data. Surely there is a way I can compress from memory to memory, avoiding the overhead of having to create a new TIFF image, and the disk activity.

I'm sure I'm overlooking something obvious; can I buy a clue?

Not that I was able to discover when I was doing a similar thing (what I needed was to encode an image using CCITT G4 for use in a PDF file). The TIFF format and the TIFF image file are too closely associated with the library. Things aren't well separated out so that you can simply perform such actions easily.

I eventually got it to work, but it was pretty ugly. Don't have the code around any more to let you know what I did, though. Sorry.

--Tim