We can't predict if the quality is going to be below the threshold
eventually, so we might as well enable it always.
Change-Id: I30aedecc8c6d4daf159f6ef152697df0206d1e93
This fixes some color smearing due to heavy quantization.
This is only enabled for q <= 30 (cf ERROR_DIFFUSION_QUALITY)
Change-Id: I07e83a4d38461357a32c9e214f7eadc6db73baa9
only supported ones are: RGBA/BGRA/rgbA/bgrA (decoder)
as well as: WebPPictureImportRGB/RGBX/RGBA (encoder).
(note: extras/get_disto is affected too)
Change-Id: If6c4f95054ca15759c4e289fb3b4c352b3521c2c
(cherry picked from commit 6de20df02c63b88f408f4b6f52830db339dfdd04)
remove auto-filter (-af) support and make WebPPictureCopy,
WebPPictureIsView, WebPPictureView, WebPPictureCrop, and
WebPPictureRescale noops.
Change-Id: If39d512cc268a0015298a1138dbc94feb86575e5
Rewrote WebPPictureHasTransparency() to use them (even for argb).
This is 10% faster, for some reasons.
SSE2 version should be straightforward.
Removes a TODO.
Change-Id: I7ad5848fc5e355e2df505dbcd5a0f42fb6cbab41
For a pixel, we look for the longest match starting in a window around it.
For the following pixel, the previous result can be used and smaller
search window is used.
Change-Id: Ice16f9a7c8754099d068380848f0d77de3f756ac
this check was relocated in:
b903b80c Split cost-based backward references in its own file.
quiets -Wundef
Change-Id: I7f7a4773fb8cc77ca9f671b11f50d5db2275d415
If "exact" is false, we can modify the luma samples in fully transparent
areas to facilitate lossy compression. Experiments on some PNG images
show compression improvement of more than 20%.
Change-Id: I1a728cfa920a6652bc1f600d87c01f7f648c4942
Half of the functionality was duplicated.
The rest is about the alpha channel handling so we
might as well put it in the appropriate file.
Change-Id: I8d5ef0afce82cc4842ab7132fd97995c42e6140a
As backward references use the plane code when checking the cost
of a distance, statistics used to compute the cost should use it too.
This provides a small compression improvement at no speed cost.
Change-Id: Icade150929ee39ef6dc0d8b1fc85973086ecf41d
quiets undefined sanitizer warnings of the form:
left shift of 128 by 24 places cannot be represented in type 'int'
Change-Id: I8a389f2ac9238513517180f302f759425eeb7262
When re-initializing a bit writer, we could set invalid values because
the bit writer was not big enough.
Change-Id: Id25ab6712603245a5a12d5f4a86fe35a9a799a5d