Re: [PATCH 6/6] Add demos/zone_plate.png
Siarhei Siamashka <[email protected]>
| Newsgroups | gmane.comp.graphics.pixman,gmane.comp.lib.cairo |
|---|---|
| Message-ID | <20121126092759.2c881d12@i7> |
On Fri, 23 Nov 2012 23:15:31 -0500 Søren Sandmann <[email protected]> wrote: > From: Søren Sandmann Pedersen <[email protected]> > > The zone plate image is a useful test case for image scalers because > it contains all representable frequencies, so any imperfection in > resampling filters will show up as Moire patterns. > > This version is symmetric around the midpoint of the image, so since > rotating it is supposed to be a noop, it can also be used to verify > that the resampling filters don't shift the image. > --- > demos/zone_plate.png | Bin 0 -> 522879 bytes > 1 files changed, 0 insertions(+), 0 deletions(-) > create mode 100644 demos/zone_plate.png Hi, the size of this PNG file can be cut in half: $ optipng -o7 zone_plate.png ** Processing: zone_plate.png 512x512 pixels, 3x8 bits/pixel, RGB Reducing image to 8 bits/pixel, grayscale Input IDAT size = 522048 bytes Input file size = 522879 bytes Trying: zc = 9 zm = 9 zs = 0 f = 0 IDAT size = 231093 zc = 8 zm = 9 zs = 0 f = 0 IDAT size = 231093 zc = 7 zm = 9 zs = 0 f = 0 IDAT size = 231093 zc = 6 zm = 9 zs = 0 f = 0 IDAT size = 231093 zc = 5 zm = 9 zs = 0 f = 0 IDAT size = 231093 zc = 3 zm = 9 zs = 0 f = 0 IDAT size = 228661 zc = 3 zm = 9 zs = 1 f = 0 IDAT size = 228661 Selecting parameters: zc = 3 zm = 9 zs = 1 f = 0 IDAT size = 228661 Output IDAT size = 228661 bytes (293387 bytes decrease) Output file size = 228732 bytes (294147 bytes = 56.26% decrease) -- Best regards, Siarhei Siamashka _______________________________________________ Pixman mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/pixman