# Resizing pictures for file size **URL:** \ **Category:** Ruby\ **Created:** [February 3, 2008, 11:30pm UTC](https://www.ruby-forum.com/t/resizing-pictures-for-file-size/127988 "2008-02-03T23:30:49Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![JSPablo\_FernSSSSnd](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e9bcb4/32.png) [@JSPablo\_FernSSSSnd](https://www.ruby-forum.com/u/JSPablo_FernSSSSnd)\ **Post date:** [February 3, 2008, 11:30pm UTC](https://www.ruby-forum.com/t/resizing-pictures-for-file-size/127988/1 "2008-02-03T23:30:49Z")
Hello, I’m using rmagick but I’m open to other libraries if needed. I want to resize an image, scale actually (mantaining the aspect ratio) so that the size of the file is lower than a certain amount of bytes. Any ideas how to do this? Thanks. ---
**Author:** ![JSPablo\_FernSSSSnd](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e9bcb4/32.png) [@JSPablo\_FernSSSSnd](https://www.ruby-forum.com/u/JSPablo_FernSSSSnd)\ **Post date:** [February 4, 2008, 12:35am UTC](https://www.ruby-forum.com/t/resizing-pictures-for-file-size/127988/2 "2008-02-04T00:35:25Z")
J. Pablo Fernández wrote: > – > J. Pablo Fernández [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ([http://pupeno.com](http://pupeno.com)) I can’t speak for other libraries, but this is not possible with RMagick. This question comes up from time-to-time on the ImageMagick forum but the answer is always “not possible” other than just by trial-and-error. ---
**Author:** ![JSPablo\_FernSSSSnd](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e9bcb4/32.png) [@JSPablo\_FernSSSSnd](https://www.ruby-forum.com/u/JSPablo_FernSSSSnd)\ **Post date:** [February 4, 2008, 2:18am UTC](https://www.ruby-forum.com/t/resizing-pictures-for-file-size/127988/3 "2008-02-04T02:18:01Z")
On Mon, 2008-02-04 at 08:34 +0900, Tim H. wrote: > > ## Thanks. > > > > J. Pablo Fernández [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) ([http://pupeno.com](http://pupeno.com)) > > I can’t speak for other libraries, but this is not possible with > RMagick. This question comes up from time-to-time on the ImageMagick > forum but the answer is always “not possible” other than just by > trial-and-error. What exactly is not possible? Resize according to the certain amount of bytes after the resize? ---
**Author:** ![JSPablo\_FernSSSSnd](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e9bcb4/32.png) [@JSPablo\_FernSSSSnd](https://www.ruby-forum.com/u/JSPablo_FernSSSSnd)\ **Post date:** [February 4, 2008, 2:30am UTC](https://www.ruby-forum.com/t/resizing-pictures-for-file-size/127988/4 "2008-02-04T02:30:19Z")
David Moreno wrote: > > > > > bytes after the resize? There is no method in RMagick that takes an image and a file size in bytes and returns an image that, when saved to a file, produces a file close to or no larger than the specified size. The file size depends on the image format, the compression level, and the image itself. ---
**Author:** ![JSPablo\_FernSSSSnd](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e9bcb4/32.png) [@JSPablo\_FernSSSSnd](https://www.ruby-forum.com/u/JSPablo_FernSSSSnd)\ **Post date:** [February 4, 2008, 3:10am UTC](https://www.ruby-forum.com/t/resizing-pictures-for-file-size/127988/5 "2008-02-04T03:10:10Z")
Marcin R. wrote: > mean and min from qualities. > > now you have 2 qualities - one that 50% of images should fit with size - > and second that almost all should fit. > > that’s assuming that your surce images have simillar resolutions. > > greets Sounds like a plan. Maybe the OP will adopt it if he can’t find a library that will do what he wants automatically. ---
**Author:** ![JSPablo\_FernSSSSnd](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/e9bcb4/32.png) [@JSPablo\_FernSSSSnd](https://www.ruby-forum.com/u/JSPablo_FernSSSSnd)\ **Post date:** [February 4, 2008, 3:03am UTC](https://www.ruby-forum.com/t/resizing-pictures-for-file-size/127988/6 "2008-02-04T03:03:42Z")
> There is no method in RMagick that takes an image and a file size in > bytes and returns an image that, when saved to a file, produces a file > close to or no larger than the specified size. The file size depends on > the image format, the compression level, and the image itself. There are tools that can estaminate size of file after compresion - but they’ll never give you exact size without actual compression. So … you take script, 20-30 simple images, take each one, start with some quality - and incrementally decrase untill size fits, then you take mean and min from qualities. now you have 2 qualities - one that 50% of images should fit with size - and second that almost all should fit. that’s assuming that your surce images have simillar resolutions. greets