Re: [hugin-ptx] Re: Best TIFF format
On 02/10/2013 02:31 AM, Frederic Da Vitoria wrote: 2013/2/10 Gnome Nomad mailto: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. Possible. I don't know how LZW works in that conjunction. Or even what algorithm JPEG uses after it's thrown out "unneeded" image data. -- Gnome Nomad gnomeno...@gmail.com wandering the landscape of god http://www.clanjones.org/david/ http://dancing-treefrog.deviantart.com/ http://www.cafepress.com/otherend/ -- -- 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.
Re: [hugin-ptx] Re: Best TIFF format
On 02/10/2013 05:04 AM, Erik Krause wrote: Am 10.02.2013 09:56, schrieb Gnome Nomad: Hmm, have never had LZW compress a 16-bit TIFF and make it LARGER than the uncompressed version. Just tested here with single-layer TIFFs converted from 48-bit RAW files (6MP image): 8-bit TIFF: 17.2 MB (uncompressed) => 6.1 MB (LZW) 16-bit TIFF: 34.4 MB (uncompressed) => 30.7 MB (LZW) Interesting. I have this all the time. Could it be photoshop LZW compression is less good? I doubt that. Photoshop would use the same LZW algorithm everyone else does. However, try the following: don't denoise in the raw conversion step and sharpen the image, then try to save LZW compressed again. Images compress better if there are less fine details. I didn't denoise them or sharpen them. They were ISO100 images from my DSLR, and have no discernible noise. One reason I use TIFF files is they don't lose fine details, or possibly express them as JPEG artifacts. I think you'd have to walk through the LZW compression algorithm itself to see where it's not being as successful with 16-bit TIFF as it is with 8-bit, if that's what you're focusing on. -- Gnome Nomad gnomeno...@gmail.com wandering the landscape of god http://www.clanjones.org/david/ http://dancing-treefrog.deviantart.com/ http://www.cafepress.com/otherend/ -- -- 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.
Re: [hugin-ptx] Re: Best TIFF format
Am 10.02.2013 09:56, schrieb Gnome Nomad: Hmm, have never had LZW compress a 16-bit TIFF and make it LARGER than the uncompressed version. Just tested here with single-layer TIFFs converted from 48-bit RAW files (6MP image): 8-bit TIFF: 17.2 MB (uncompressed) => 6.1 MB (LZW) 16-bit TIFF: 34.4 MB (uncompressed) => 30.7 MB (LZW) Interesting. I have this all the time. Could it be photoshop LZW compression is less good? However, try the following: don't denoise in the raw conversion step and sharpen the image, then try to save LZW compressed again. Images compress better if there are less fine details. -- Erik Krause -- -- 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.
Re: [hugin-ptx] Re: Best TIFF format
2013/2/10 Gnome Nomad > > 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.
Re: [hugin-ptx] Re: Best TIFF format
On 02/05/2013 10:48 AM, Frederic Da Vitoria wrote: 2013/2/5 Erik Krause mailto:erik.kra...@gmx.de>> Am 05.02.2013 09:58, schrieb MaTa: Please I need you help. I always export my photos from Lighthoom as TIFF 16bits, LZW compressed at full resolution/size. It's the best way? LZW doesn't compress 16 bit very good. In fact I found LZW compressed 16 bit TIFFs larger than the uncompressed version most of the time. Hmm, have never had LZW compress a 16-bit TIFF and make it LARGER than the uncompressed version. Just tested here with single-layer TIFFs converted from 48-bit RAW files (6MP image): 8-bit TIFF: 17.2 MB (uncompressed) => 6.1 MB (LZW) 16-bit TIFF: 34.4 MB (uncompressed) => 30.7 MB (LZW) 8-bit JPG: 4 MB LZW compresses both TIFFs to less than the original size. Just for grins, same results using ImageMagick's ZIP compression option: ZIP compressed 8-bit TIFF: 5.7 MB ZIP compressed 16-bit TIFF: 25.5 MB And DevalVR standalone (which is my favorite spherical viewer) doesn't show LZW compressed TIFFs... Sounds like a feature they should add. But TIFFs aren't used much for image display on the web, because they're too large. 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. -- Gnome Nomad gnomeno...@gmail.com wandering the landscape of god http://www.clanjones.org/david/ http://dancing-treefrog.deviantart.com/ http://www.cafepress.com/otherend/ -- -- 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.
Re: [hugin-ptx] Re: Best TIFF format
2013/2/5 Bruno Postle > On Tue 05-Feb-2013 at 21:48 +0100, Frederic Da Vitoria wrote: > > 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. >> > > You need to be careful how you do this, if you convert a JPEG to TIFF with > ImageMagick then you end up with a JPEG compressed TIFF. > I did it with Gimp, the tiff export options are (among others) uncompressed, lzw, jpg. Also, the compressed tiff was still more than 3 times as large as the original jpeg. I just checked that tiff with jpeg compression gives a size similar to the original. -- 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.
Re: [hugin-ptx] Re: Best TIFF format
On Tue 05-Feb-2013 at 21:48 +0100, Frederic Da Vitoria wrote: 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. You need to be careful how you do this, if you convert a JPEG to TIFF with ImageMagick then you end up with a JPEG compressed TIFF. -- Bruno -- -- 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.
Re: [hugin-ptx] Re: Best TIFF format
2013/2/5 Erik Krause > Am 05.02.2013 09:58, schrieb MaTa: > > Please I need you help. I always export my photos from Lighthoom as TIFF >> 16bits, LZW compressed at full resolution/size. It's the best way? >> > > LZW doesn't compress 16 bit very good. In fact I found LZW compressed 16 > bit TIFFs larger than the uncompressed version most of the time. And > DevalVR standalone (which is my favorite spherical viewer) doesn't show LZW > compressed TIFFs... > 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. -- 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.
