MultiPage, but single file TIFFs - Hundreds of Images Lost.

[rjt]

Opening a 100 page mulitpage TIFF file and then saving it deletes 99 pages without any warning. Our scanning employees lost a great deal of work today trying out a great new program.

Please look at the following website

http://www.mikekohn.net/file_formats/tiff.php

which explains the compression involved in CCITT Group 4 Fax.

The TIFF format is the standard in document imaging and document management systems using CCITT Group IV 2D compression, which supports black-and-white (bitonal, monochrome) images. In high-volume storage scanning, documents are scanned in black and white (not in colour or in grayscale) to conserve storage capacity. An average A4 scanning produces 30 KB of data at 200 ppi (pixels per inch of resolution) and 50 KB of data at 300 ppi; 300 ppi is more common than 200 ppi.

The TIFF format can save multi-page documents to a single TIFF file rather than a series of files for each scanned page. Multi-page support and 2D compression of bitonal images led to the TIFF's becoming the standard storage format facsimiles, especially on Fax Servers.

[Mike Ryan]

TIFF stands for 'Tagable Image File Format' which means that there is no way that one single program could have support for every variation of a TIFF file. I am sorry to hear about your loss, but you must understand the image format and why certain aspects are not supported.

[Rick Brewster]

Paint.NET supports TIFF mostly as a convenience because it was very easy to add the support. It's not really designed to be a good TIFF editor, and it can't save in the 1-bit format.

[rjt]

i understand it is complicated, but there are still options that a reasonable developer would consider:

1.) Easy - Refuse to resave a TIFF file unless the user affirms they are super sure that they are willing to risk losing secondary pages. Optional warning on by default.

2.) More Complex - Detect if there is more than one page in a TIFF and just flat out refuse to save.

Our scanners scan 30 pages or so per minute and the original paper had not made it to the shredder, so we were ok. However, i noticed this problem years ago and so was able to show them what happened. They had no idea that they lost about everything - there is no warning and the first page appears ok.