[TYPO3-dev] JPEG quality

[Thomas "Thasmo" Deinhamer]

Franz Koch wrote:
> Hey,

Hey ho!

>> I tend to have a default of 55 and raise it up to
>> 75 if needed.
>
> my default in TYPO3 is 70. Everything lower then that just looks awful
> with 50% of the images.
> When exporting images from Photoshop etc I'm using 55 as default, which
> is about the same quality level as 70/75 with imagemagick.

Ah, thanks for that hint. I didn't yet realize that Photoshop 55%
will match to about 70/75% when using ImageMagick.

>> The problem we have with clients is that they sometimes
>> complain that images (especiall RED ones) look "awful"
>> in their oppinion. Unfortunately this is true to a
>> certain degree - red images/jpegs look not as good
>> as other colors.
>
> The JPG algorithm in general has a issue with the color red (especially
> saturated shades covering larger areas). And compared to other tools
> imageMagick/graphicsMagick don't have the best JPG implementation.
> Whereas all tools creating JPGs (also Photoshop) have issues with red
> colors, from my experience they deal a bit better with it.

Indeed, happens within larger areas.

>> This ends up in setting the quality to 90 or even higher
>> to satisfy the customer - but imo this really bugs me!!
>
> my limit is 90 - if customers still complain I say it's already the
> maximum setting and they can live with it.
>
>> How do you handle this? How to you argument a higher
>> compression ratio?
>
> there are no arguments as long as the used images look like crap. A
> website is a 24/7 representation of the customer/company, so it has to
> look good and professional. Of course it should also be loaded fast, but
> most customers don't care about that - so they should get what the ask
> for. I can only advise them - if they don't care it's not my problem and
> not my fault. Easy as that.
>
> The only thing you could do is to advise the customer to use PNG instead
> of JPG for images that are no photos but stuff like diagrams.

The problem with our TYPO3 installations using PNG is, that
these images get _drastically_ huge after ImageMagick resizes them.
(There must be some sort of issue with TYPO3 and the version
of IM we use or anything else which would cause this.)

Thanks for your detailed reply anyway!

Thomas