[TYPO3-dev] JPEG quality

[Thomas "Thasmo" Deinhamer]

Franz Koch wrote:
> To complete the lecture about images and sizes :), the size of PNGs
> depends of course on the complexity of the image and it's original
> format. If the image was a JPG and should be rendered as PNG, then it's
> getting blown up in filesize by no means, due to the "noise" JPG is
> creating. But PNG/GIF resized and rendered as PNG again should have a
> moderate filesize though. Blurred edges and gradients also increase the
> filesize of PNGs of course - so sharpening and/or limiting the max
> colors will lead to smaller file sizes in those cases. PNG is only
> useful for "flat" graphics like diagrams, most Logos and images showing
> text and large areas of the same color. Anything with gradients or real
> photos is best saved as JPG.

Yeah, basically that's what I've also encountered, but in our case PNGs
which are just resized by ImageMagick increase their filesize immense.

E.g. if I check the image test #3 in the install tool at "PNG to PNG, 
150 pixels wide", the PNG on our server is 35K, while the reference is
only 4,1K. Now you can imagine images with dimensions like 640x480 have
a filesize which is just too large to download, even for super high
speed internet connections. (The images are really insanely huge.)

But I think there are some recent bugs which are beeing worked on
for 4.5, besides BE/FE login/session problems etc.

Thomas