XnView Software

Dear xnview advanced users,

Perhaps you can advise me on following.

• I have created two TIFF colour images with ZIP compression.
• I have selected them and then applied Create → Multi Page file (Format = TIFF, Options: Color compression = JPEG, Filename = result).

The original file sizes were 10Mb+10Mb. The resulting file size is 8Mb which is too big: when I convert the source files to JPEG with 80% quality I get sizes 500K+500K. Even if I use 100% quality, I get 3Mb+3Mb = 6Mb size, but not 8Mb.

I wonder, if saving to TIFF uses the write options for JPEG?

Also how is it possible to extract JPEG data from TIFF and save it as JPEG (loseless)?

Thanks.

dma_k wrote:when I convert the source files to JPEG with 80% quality I get sizes 500K+500K. Even if I use 100% quality, I get 3Mb+3Mb = 6Mb size, but not 8Mb.

I wonder, if saving to TIFF uses the write options for JPEG?

Oh right, the quality for TIFF jpeg is option/Write/Jpeg>quality, i'll add a quality settings in tiff options

xnview wrote:Oh right, the quality for TIFF jpeg is option/Write/Jpeg>quality, i'll add a quality settings in tiff options

I would be happy if it is so. But my calculations cannot prove this...

dma_k wrote:

xnview wrote:Oh right, the quality for TIFF jpeg is option/Write/Jpeg>quality, i'll add a quality settings in tiff options

I would be happy if it is so. But my calculations cannot prove this...

Is it possible to have the 2 tiff files?

Xnview does -not- use the tools->options->jpeg settings for jpeg compression of tiffs & never has for as long as I've used it. Perhaps that's how it's supposed to work, but it doesn't.
Go to the jpeg settings, set the quality very high, save an image as a tiff with jpeg compression. Now go back & set the jepg quality very low, save the same image as tiff with jpeg compression. Now compare the 2 resulting files. The filesize is identical.
Other settings such as progressive, DCT, smoothing, etc likewise have no effect on the tiff.

ok, i'll check...

I have also noticed SamplesPerPixel: 3 in properties for the this kind of images. Is there any way to set the higher quality (2x2 and 1x1 samples)?

The problem is not connected with multi-page processing, but rather with saving of TIFF images with JPEG compression. Just "save as" the original TIFF image (with colour compression set to JPEG), and afterwards convert the original TIFF file into JPEG (quality value is the same in my case). I've got the 5x difference in size, although I suppose the size should be nearly the same. Or TIFF container can't use the same algorithms / optimizations / profiles, applicable for normal JPEG?

P.S. I've found similar issue related to ImageMagic.