2009.10.28 09:01 "[Tiff] Number of images in a multi-tiff file?", by Mark Pereira

2009.10.28 16:22 "Re: [Tiff] Number of images in a multi-tiff file?", by Frank Warmerdam

On Wednesday 28 October 2009 20:01:21 Mark Pereira wrote:

Is there a way to know the number of images present in a multi-tiff file in constant time.

TIFFNumberOfDirectories()?

Mark,

No, there is not since the directory list needs to be walked to count them. The count is not available in a header or anything like that.

Skimming the code briefly it appears that TIFFNumberOfDirectories() is careful to read the minimum amount of information from the file (a few numbers from the start of each directory) to count through the file so the cost should be minimal, but not constant time.

Best regards,
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