From: Chandrabhanu Mahapatra Date: Mon, 19 Dec 2011 08:33:44 +0000 (+0530) Subject: OMAPDSS: DISPC: Update Fir Coefficients X-Git-Tag: v3.3-rc1~59^2~2^2~9 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=debd90749b7440ad5fc02e4f0d1e8a696385f196;p=pandora-kernel.git OMAPDSS: DISPC: Update Fir Coefficients The FIR coefficients present in kernel are being updated to new coefficients consisting of 24 coefficient tables, with 12 each for 3 tap and 5 tap scenario, which are chosen on the basis of DISPC up/downsampling filters M value. M is the inverse of low pass cut off frequency of the sampling filter. For vertical scaling 3 tap or 5 tap tables are used based on the clock rate and width of the line buffer whereas in OMAP2 3 tap is always used. For horizontal scaling however 5 tap tables are always used. New coefficients and the corresponding logic have been tested on OMAP2, OMAP3 and OMAP4. Horizontal and vertical scaling worked fine except for some 3 tap vs 5 tap issue during vertical upscaling and clock failing issues which is acknowledged in the next patch. Vertical upscaling was found to perform better under 5 taps. The 24 coefficient tables have been moved to another file dispc_coefs.c for proper maintainance. This code is written based on code written by Lajos Molnar in Android Kernel for scaling. Lajos Molnar had fine tuned the FIR coefficient selection process and reduced outliness and blockiness around images when upscaling more than 2 times. Signed-off-by: Chandrabhanu Mahapatra Signed-off-by: Tomi Valkeinen --- Reading git-diff-tree failed