Thomas Mundt a7f6bfdc18 avfilter/interlace: prevent over-sharpening with the complex low-pass filter ... The complex vertical low-pass filter slightly over-sharpens the picture. This becomes visible when several transcodings are cascaded and the error potentises, e.g. some generations of HD->SD SD->HD. To prevent this behaviour the destination pixel must not exceed the source pixel when the average of the pixels above and below is less than the source pixel. And the other way around. Tested and approved in a visual transcoding cascade test by video professionals. SSIM/PSNR test with the first generation of an HD->SD file as a reference against the 6th generation(3 x SD->HD HD->SD): Results without the patch: SSIM Y:0.956508 (13.615881) U:0.991601 (20.757750) V:0.993004 (21.551382) All:0.974405 (15.918463) PSNR y:31.838009 u:48.424280 v:48.962711 average:34.759466 min:31.699297 max:40.857847 Results with the patch: SSIM Y:0.970051 (15.236232) U:0.991883 (20.905857) V:0.993174 (21.658049) All:0.981290 (17.279202) PSNR y:34.412108 u:48.504454 v:48.969496 average:37.264644 min:34.310637 max:42.373392 Signed-off-by: Thomas Mundt <tmundt75@gmail.com> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>		2017-09-15 22:40:21 +02:00
..
api	tests: do not use AVFrame accessor	2017-04-23 14:47:54 +07:00
checkasm	checkasm: use perf API on Linux ARM*	2017-09-08 18:51:05 +02:00
fate	fate: add test for asetnsamples filter with padding disabled	2017-09-08 08:54:20 +02:00
filtergraphs	FATE: Add test for libavfilter/scale2ref	2017-06-05 01:50:25 +02:00
ref	avfilter/interlace: prevent over-sharpening with the complex low-pass filter	2017-09-15 22:40:21 +02:00
.gitignore
audiogen.c
audiomatch.c
base64.c
copycooker.sh
extended.ffconcat
fate-run.sh	fate: use do_md5sum instead of the md5 protocol for most md5 fate tests	2017-06-18 23:19:48 +02:00
fate-valgrind.supp
fate.sh	Merge commit '35d1f726eb9fdd376ab900587fb02122b72f2b9a'	2017-05-05 09:27:18 +02:00
ffserver-regression.sh
ffserver.conf
ffserver.regression.ref
lavf-regression.sh	FATE: Add FITS tests	2017-08-30 12:13:02 +02:00
Makefile	fate/pixlet : add test for rgb	2017-08-31 02:53:11 +02:00
md5.sh
reference.pnm
regression-funcs.sh
rotozoom.c
simple1.ffconcat
simple2.ffconcat
test.ffmeta
tiny_psnr.c
tiny_ssim.c
utils.c
videogen.c