Resizing to Specific File Size

Hey guys,

In an effort to not violate the 1st rule of forums, I have spent the last several minutes searching to see if my question has already been answered. Unfortunately I did not find it.

What I want to do, is like the title says. I need to batch resize images to a specific file size. I do not want to have to set the longest side, or change that kind of thing. I will be doing this for thousands of images at a time, some vertical, some horizontal, many starting out at different file sizes.

So for example if I have 2,000 images that are all between 70-100mb and I need them all to be 50mb each to send out. Is there a program that can do this?

I know in PS you can do "Save for Web" but that limits you to I believe 2mb file size. I need high resolution images.

Also, if there is indeed a thread already created on this topic that I missed, please feel free to just guide me in that direction. I dont mind reading

Cheers,
Brian

Lightroom will do this upon export, but I think it accomplishes the file size requirement by on-the-fly adjustment of the jpeg quality/compression level.

At my day job as a professional cubicle jockey, we occasionally use FastStone image resizer but that doesn't seem to have any file size option.

Thanks for the feedback, I will checkout the Lightroom option

The image processor in Photoshop should be able to do it.
File > Scripts > Image Processor...

With Lightroom, the assumption is that you want it to Export JPG files from RAW, and you want LR to resize to certain pixel resolution dimensions (H x V). Another alternative, if you have JPG files already at some larger size (such as JPG direct from camera) is to use a program like Paintshop Pro, and have it execute a script on files, to Image Resize (to certain percentage or to certain pixel count) and Save the result in a specified location

Having a jpeg at 50 meg does not make sense, do you mean a minimum of 50meg uncompressd?(size given in Photoshop), this is what a lot of places require, not the file size on HDD.

Normally I would agree, but it is for a stock photo agency. Many of the images are HDR (proper HDR) images of interiors etc. that are very high resolution to start with. When someone purchases an image, they need to have the highest resolution possible in all file types. Depending on licensing agreements they get a different resolution delivered to them.

I dont see a way in image processor to set the desired file size.

Lightroom will only set a maximum and even that will not be exact. If you specify a 500 KB max, you might get 432 KB, it all depends on how the compression goes.

I still think you should check with the agency as I believe they are asking for the uncompressed size that shows in photoshop, this can be adjusted with a script IE:

if(documents.length) resizeToFiftyMeg();
function resizeToFiftyMeg(){
var SizeOfFile = 50; //This is the actual size required.
var current_units = preferences.rulerUnits​; 
preferences.rulerUnits = Units.PIXELS;  
var width_pixels = activeDocument.width; 
var height_pixels = activeDocument.height; 
var channel_count = activeDocument.channel​s.length; 
var image_bytes = width_pixels * height_pixels; 
var actual =((image_bytes/1024/10​24)*channel_count).toF​ixed(2);
if(actual >= SizeOfFile) return;
var final_size = ( 1024 * 1024 * SizeOfFile ) / channel_count; 
var image_scale = Math.sqrt( final_size/ image_bytes ); 
var final_width = width_pixels * image_scale; 
var final_height = height_pixels * image_scale; 
var final_ppi = activeDocument.resolut​ion;
activeDocument.resizeI​mage( final_width, final_height, final_ppi, ResampleMethod.BICUBIC​SMOOTHER );
preferences.rulerUnits = current_units; 
}