Lack of interest Image processing for attachments with jpegtran


Active member
Most of my users upload images in baseline format. If uploaded images are processed through a cron job once everyday using a jpegtran we can improve the performance of the site.This would benefit not just loading speeds we could also use such an option to brand images.

ImageMagick is also another linux tool that could be used.


Active member
What sort of processing would be done? ImageMagick is already an option to use.
Reduce the size of original image file without much loss in quality. Some old Jpegs floating around the web are so bloated that we can take more than 70% of their file size.
Another option is to use Yahoo's smush it service. but we need to wait for some more time.

And this is what they use

We have found many good tools for reducing image size. Often times these tools are specific to particular image formats and work much better in certain circumstances than others. To "smush" really means to try many different image reduction algorithms and figure out which one gives the best result.

These are the algorithms currently in use:

  1. ImageMagick: to identify the image type and to convert GIF files to PNG files.
  2. pngcrush: to strip unneeded chunks from PNGs. We are also experimenting with other PNG reduction tools such as pngout, optipng, pngrewrite. Hopefully these tools will provide improved optimization of PNG files.
  3. jpegtran: to strip all metadata from JPEGs (currently disabled) and try progressive JPEGs.
  4. gifsicle: to optimize GIF animations by stripping repeating pixels in different frames.


Well-known member
Some members would get very upset if I did any compression on their image attachments.


Active member
Some members would get very upset if I did any compression on their image attachments.
Compression here is changing algorithm that is encoding here not size. I don't think most users would know whether their image is in baseline or progressive format has already been suggested. API is not available at the moment. On server processing of images don't take much processing power.


Active member
I looked into it but it takes up cpu resources and i like to optimise files individually so you have a better control
Not to sound pushy, but you should give it another shot and play with the config, then let it run for a few weeks. If you don't use settings that use a lot of extra CPU on each request then the initial CPU overhead is only high as it builds the initial cache. After that it's pretty much serving pages out of the cache and it stops processing things on each request.