How can I predict which image will big smaller ?

palkia has asked for the wisdom of the Perl Monks concerning the following question:

Hi everyone.
I'm trying to find a way to predict which image (Imager)
will take the smaller size once saved to a file (before saving).
Since I'm planning this process to run many times,
I don't want to slow down my program by actually saving the images to files and than comparing sizes, and removing the bigger one.

Your thoughts ?
Thx

Comment on How can I predict which image will big smaller ?

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Re: How can I predict which image will big smaller ? by BrowserUk (Patriarch) on Aug 03, 2012 at 14:55 UTC
Why not have it write all the filetypes to a ramfile first: `my %sizes; for my $type ( Imager->write_types ) { open my $ramFH, '>:raw', \$buffer; $im->write( fh => $ramFH, type => $type ); $sizes{ length $buffer } = $type; } ## Pick type of smallest my $filetype = $sizes{ (sort{ $a <=> $b } keys %sizes)[0] }; ## write to real file ...` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. The start of some sanity?	[reply] [d/l]
Re: How can I predict which image will big smaller ? by ww (Archbishop) on Aug 03, 2012 at 15:06 UTC
Did you read the documentation? ... especially `# try to save in one of these formats SAVE:`" (assumption: you mean smaller file size). Or, "`# Create smaller version # documented in Imager::Transformations`" if "smaller size" refers to dimensions in pixels.	[reply]