Quality adjustment

i3, our image management solution, allows for dynamic and transparent adjustment of image quality.

We achieve this by using our TCDN-i3-transform header and specifying the desired operation, in this case, quality. This operation requires a mandatory parameter: the quality level expressed as a percentage, indicating the resulting image's quality compared to the original image.

The exact syntax for this operation is as follows: quality:<porcentaje>%

However, there is an important restriction to note: this operation is only applicable to images in JPEG format (conversion to WebP has its own quality adjustment). For images in other formats, you can alternatively consider using the max_length operation, which is not limited by the image format.

For example, if we wanted all images on our domain mi-dominio.es under the URL /estaticos/imagenes to be served with a reduced quality of 75%, we would simply need to deploy a VCL configuration similar to the following from the dashboard:

# i3 - quality
sub vcl_recv {
    if (req.http.host == "www.mi-dominio.es") {
        if (req.url ~ "^/estaticos/imagenes/") {
            if (urlplus.get_extension() ~ "(?i)(jpe?g)") {
                set req.http.TCDN-i3-transform = "quality:75%";
            }
        }
    }
}