2013/2/10 Gnome Nomad <gnomeno...@gmail.com> > > I just did a test with a jpg original, it lost 50% size with compressed >> tiff besides uncompressed tiff. But maybe a jpeg image lends itself well >> to compression. >> > > JPEG compresses by *throwing out parts of the image* like MP3 and other > audio formats. It is a LOSSY compression method. What they throw out is > determined by psycho-perceptual studies that showed, "We can throw this out > because the average human eye/ear doesn't really perceive them very well." > TIFF doesn't lose any parts of the image. > > When you uncompress a TIFF, you get back the exact image you compressed. > > When you uncompress a JPEG, you get back something that "looks" like the > uncompressed image, but isn't an exact match.
Yes, I know this. What I meant is that a JPEG image has much less data in it than for example a RAW image, precisely because JPEG compression throws out data. IIUC, one of JPEG's ways of compressing data is restricting the colour palette locally. It seems intuitively plausible that a JPEG image would lend itself better to LZW compression, because the colours variety would be locally poorer than in a RAW and this would make LZW more up to the task. -- Frederic Da Vitoria (davitof) Membre de l'April - « promouvoir et défendre le logiciel libre » - http://www.april.org -- -- You received this message because you are subscribed to the Google Groups "Hugin and other free panoramic software" group. A list of frequently asked questions is available at: http://wiki.panotools.org/Hugin_FAQ To post to this group, send email to hugin-ptx@googlegroups.com To unsubscribe from this group, send email to hugin-ptx+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/hugin-ptx --- You received this message because you are subscribed to the Google Groups "hugin and other free panoramic software" group. To unsubscribe from this group and stop receiving emails from it, send an email to hugin-ptx+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/groups/opt_out.
