Pending Problems reading large compressed tiff files with single strip per image

[DonM]

I have a program that saves large multi-page tiff files (multiple frames per file). This is data streamed from a high speed (250 fps) camera, and I generate files up to just under 2 GB in size. Normally, to maximize throughput, I save the data uncompressed, using a single strip for each image. Irfanview has no problems opening and displaying these files.

At slower frame rates I will save the data compressed (tiff with LZW) to save space. I keep the number of frames in the file the same, so that when uncompressed, the file size would still be below 2 GB. If I strip the data with the usual 8KB strips, again Irfanview has no problems. However, if I write compressed data with one strip per frame, Irfanview has problems displaying these. The initial frames are displayed as all black, then the rest of the frames display correctly. For a file which is close to 2 GB when uncompressed (about 1 GB compressed), it displays around the first 400 frames as black, out of 3500.

This is not a big issue for me (now that I understand it), because I can write striped data when using compression. Compressing the data is so slow that any difference between striped and non-striped is irrelevant.

I am not sure you want to bother looking into this, as I am probably the only user who has or will run into it. If you do want to look into this, do you have a way to generate large multi-page tiff files, with and without compression, and with and without stripping? If not, I can try to figure out how to get you a test file, and/or copies of the libtiff utilities.

Thanks for your excellent program
Don

[derniwi]

Hi Don,

I'm not sure if I can help you with this problem. Irfan usually does not read this forum, soi if it is a big deal contact him directly.

But one thing I know is that IView can just allocate 2GB of Ram since it is an 32 Bit application. So opening a file with almost 2GB may cause such a problem, a file with compressed data inside which are close to 2GB if it will be uncompressed may also make trouble because IView has to load the data and has to uncompress it. And if this will exceed the 2GB several effects are possible.

But again, ask Irfan if you need more information about this problem and how to avoid it.

Regards
Nils

[DonM]

To follow-up: I emailed Irfan about this issue. He found the problem is in an older version of LibTiff that he was using. He sent me a test build with a newer version of LibTiff, and that fixed the problem. Presumably this will be included in the next version of Irfanview (4.34).

As far as I am concerned, you can mark this issue fixed.

Regarding files close to 2 GB -- in a multii-page tiff file, Irfanview only reads the current image. So the entire file can be up to 2 GB in size, and Irfanview can read the file and display individual images (pages) from it without problems.

Thanks,

Don