FFmpeg

580MB

Tree: a9c20e922c

Author	SHA1	Message	Date
Ganesh Ajjanagadde	92e483f8ed	all: use FFDIFFSIGN to resolve possible undefined behavior in comparators FFDIFFSIGN was created explicitly for this purpose, since the common return a - b idiom is unsafe regarding overflow on signed integers. It optimizes to branchless code on common compilers. FFDIFFSIGN also has the subjective benefit of being easier to read due to lack of ternary operators. Tested with FATE. Things not covered by this are unsigned integers, for which overflows are well defined, and also places where overflow is clearly impossible, e.g an instance where the a - b was being done on 24 bit values. Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Reviewed-by: Clément Bœsch <u@pkh.me> Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>	10 years ago
Ganesh Ajjanagadde	68a0a164d1	avfilter/vf_removegrain: replace qsort with AV_QSORT filter_slice calls qsort, so qsort is in a performance critical position. AV_QSORT is substantially faster due to the inlining of the comparison callback. Thus, the increase in performance is worth the increase in binary size. Sample benchmark (x86-64, Haswell, GNU/Linux), filter-removegrain-mode-02 (from FATE) new: 24060 decicycles in qsort, 1 runs, 0 skips 15690 decicycles in qsort, 2 runs, 0 skips 9307 decicycles in qsort, 4 runs, 0 skips 5572 decicycles in qsort, 8 runs, 0 skips 3485 decicycles in qsort, 16 runs, 0 skips 2517 decicycles in qsort, 32 runs, 0 skips 1979 decicycles in qsort, 64 runs, 0 skips 1911 decicycles in qsort, 128 runs, 0 skips 1568 decicycles in qsort, 256 runs, 0 skips 1596 decicycles in qsort, 512 runs, 0 skips 1614 decicycles in qsort, 1024 runs, 0 skips 1874 decicycles in qsort, 2046 runs, 2 skips 2186 decicycles in qsort, 4094 runs, 2 skips old: 246960 decicycles in qsort, 1 runs, 0 skips 135765 decicycles in qsort, 2 runs, 0 skips 70920 decicycles in qsort, 4 runs, 0 skips 37710 decicycles in qsort, 8 runs, 0 skips 20831 decicycles in qsort, 16 runs, 0 skips 12225 decicycles in qsort, 32 runs, 0 skips 8083 decicycles in qsort, 64 runs, 0 skips 6270 decicycles in qsort, 128 runs, 0 skips 5321 decicycles in qsort, 256 runs, 0 skips 4860 decicycles in qsort, 512 runs, 0 skips 4424 decicycles in qsort, 1024 runs, 0 skips 4191 decicycles in qsort, 2046 runs, 2 skips 4934 decicycles in qsort, 4094 runs, 2 skips Reviewed-by: Michael Niedermayer <michael@niedermayer.cc> Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>	10 years ago
James Darnley	bff7242608	avfilter/vf_removegrain: add x86 and x86_64 SSE2 functions Speed of all modes increased by a factor between 7.4 and 19.8 largely depending on whether bytes are unpacked into words. Modes 2, 3, and 4 have been sped-up by a factor of 43 (thanks quick sort!) All modes are available on x86_64 but only modes 1, 10, 11, 12, 13, 14, 19, 20, 21, and 22 are available on x86 due to the number of SIMD registers used. With a contribution from James Almer <jamrial@gmail.com>	10 years ago
Paul B Mahol	ae55fc82a8	avfilter/vf_removegrain: clip to uint16 instead to uint8 This is how original filter behaves. Signed-off-by: Paul B Mahol <onemda@gmail.com>	10 years ago
Paul B Mahol	91748662bc	avfilter: add removegrain Signed-off-by: Paul B Mahol <onemda@gmail.com>	10 years ago

5 Commits (a9c20e922cee435c9ad2dc78f6c50651f353329c)