A friend of mine has some quite larges images that needed resizing, so I told him about XnView.
He claims that the program can't handle the images ...
I wonder.. what is the max size XnView can handle ?
Very large images
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Re: large images
To clarify the question, I meant to say "What is the max FILE size XnView can handle ?"RaymondT wrote:I wonder.. what is he max size XnView can handle ?
If you have a modern OS like Win 2000 or XP, think the only thing that limits XnView from reading large files is the available memory (RAM). As you know, if the operating system (OS) has to swap to hard disk, all programs will get VERY slow and opening an image may take ages. If an image should be handled in XnView, the image should fully fit into the phyiscal memory (RAM).
So on Aokromes' system with 1024 MByte RAM, a 15000 x 15000 image opens without problems, whereas on an old system with less memory this image might cause problems, already.
Some calculation and numbers for those interested:
In an image with true colour (16 Mio. possible colours per pixel), one pixel of the image will need 8 bit per colour (Red, Green, and Blue), that is 24 bit altogether, which are 3 Bytes per pixel.
So the memory needed for the image calculates:
Image size (uncompressed) = Width [pixel] x Height [pixel] x 3 Bytes
For example:
6000 x 6000 pixels x 3 Bytes = 108,000,000 Bytes = 103 MBytes (Remember that 1 MByte has 1024 x 1024 Bytes)
8000 x 8000 pixel: ~ 192 MByte
9000 x 9000 pixel: ~ 256 MByte
13000x13000 pixel: ~512 MByte
Since the OS, drivers, virus scanner, and other programs started use memory, the image's size must be actually even smaller.
This is just some theories on image sizes and memory usage without considering or knowing XnView internals and optimizations. Pierre knows XnView best, so I am sure that he can give some background info, too. Perhaps other people can add their experience with opening and saving large images in XnView, here.
So on Aokromes' system with 1024 MByte RAM, a 15000 x 15000 image opens without problems, whereas on an old system with less memory this image might cause problems, already.
Some calculation and numbers for those interested:
In an image with true colour (16 Mio. possible colours per pixel), one pixel of the image will need 8 bit per colour (Red, Green, and Blue), that is 24 bit altogether, which are 3 Bytes per pixel.
So the memory needed for the image calculates:
Image size (uncompressed) = Width [pixel] x Height [pixel] x 3 Bytes
For example:
6000 x 6000 pixels x 3 Bytes = 108,000,000 Bytes = 103 MBytes (Remember that 1 MByte has 1024 x 1024 Bytes)
8000 x 8000 pixel: ~ 192 MByte
9000 x 9000 pixel: ~ 256 MByte
13000x13000 pixel: ~512 MByte
Since the OS, drivers, virus scanner, and other programs started use memory, the image's size must be actually even smaller.
This is just some theories on image sizes and memory usage without considering or knowing XnView internals and optimizations. Pierre knows XnView best, so I am sure that he can give some background info, too. Perhaps other people can add their experience with opening and saving large images in XnView, here.
