The rationale for this function is reflected in the documentation for
it, and is copied here:
Clip a double value into the long long amin-amax range.
This function is needed because conversion of floating point to integers when
it does not fit in the integer's representation does not necessarily saturate
correctly (usually converted to a cvttsd2si on x86) which saturates numbers
> INT64_MAX to INT64_MIN. The standard marks such conversions as undefined
behavior, allowing this sort of mathematically bogus conversions. This provides
a safe alternative that is slower obviously but assures safety and better
mathematical behavior.
API:
@param a value to clip
@param amin minimum value of the clip range
@param amax maximum value of the clip range
@return clipped value
Note that a priori if one can guarantee from the calling side that the
double is in range, it is safe to simply do an explicit/implicit cast,
and that will be far faster. However, otherwise this function should be
used.
avutil minor version is bumped.
Reviewed-by: Ronald S. Bultje <rsbultje@gmail.com>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This is of use for defining comparator callbacks. Common approaches like
return x-y are not safe due to the risks of overflow.
Furthermore, the (x > y) - (x < y) trick is optimized to branchless
code.
This also documents this macro accordingly.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
This macro avoids the undefined corner case with the *_MIN values
Previous version Reviewed-by: Ganesh Ajjanagadde <gajjanag@mit.edu>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
there already is a function, av_clip_uintp2() that clips a signed integer
to an unsigned power-of-two range, i.e. 0,2^p-1
this patch adds a function av_clip_intp2() that clips a signed integer
to a signed power-of-two range, i.e. -(2^p),(2^p-1)
the new function can be used as a special case for av_clip(), e.g.
av_clip(x, -8192, 8191) can be rewritten as av_clip_intp2(x, 13)
there are ARM instructions, usat and ssat resp., which map nicely to these
functions (see next patch)
Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
programs using ffmpeg that are compiled with -Wshorten-64-to-32
gives a warning when using header files common.h and rational.h
cast 64-bit truncated values to (uint32_t) to avoid the warning
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
As far as I can tell the code should not change behaviour
depending on locale in any of these places.
Signed-off-by: Reimar Döffinger <Reimar.Doeffinger@gmx.de>
* commit '3b4296f41473a5b39e84d7a49d480624c9c60040':
avformat: clarify stream id for muxing
fate: Add dependencies for aac, alac, amrnb, amrwb, atrac tests
ppc: do not pass redundant compiler flags
avutil: change GET_UTF8 to not use av_log2()
segment: fix NULL pointer dereference in seg_write_header()
Conflicts:
tests/fate/aac.mak
Merged-by: Michael Niedermayer <michaelni@gmx.at>
* commit 'd15c21e5fa3961f10026da1a3080a3aa3cf4cec9':
avutil: Add a copy of ff_sqrt_tab back into avutil to restore ABI compatibility
avutil: make some tables visible again
avutil: remove inline av_log2 from public API
celp_math: rename ff_log2 to ff_log2_q15
Conflicts:
libavutil/libavutil.v
Merged-by: Michael Niedermayer <michaelni@gmx.at>
This removes inline av_log2 and av_log2_16bit from the public API,
instead exporting them as regular functions. In-tree code still
gets the inline and otherwise optimised variants.
Signed-off-by: Mans Rullgard <mans@mansr.com>
* qatar/master: (22 commits)
g723.1: do not pass large structs by value
g723.1: do not bounce intermediate values via memory
g723.1: declare a variable in the block it is used
g723.1: avoid saving/restoring excitation
g723.1: avoid unnecessary memcpy() in residual_interp()
g723.1: make postfilter write directly to output buffer
g723.1: drop unnecessary variable buf_ptr in formant_postfilter()
g723.1: make scale_vector() output to a separate buffer
g723.1: make autocorr_max() work on an arbitrary buffer
g723.1: do not needlessly use int64_t
g723.1: use saturating addition functions
g723.1: optimise scale_vector()
g723.1: remove useless uses of MUL64()
g723.1: remove unnecessary argument 'shift' from dot_product()
g723.1: deobfuscate "(x << 4) - x" to "15 * x"
celp: optimise ff_celp_lp_synthesis_filter()
libavutil: add saturating addition functions
cllc: Implement ARGB support
cllc: Add support for QRGB
cllc: Rename some funcs to represent what they actually do
...
Conflicts:
LICENSE
libavcodec/g723_1.c
libavcodec/x86/Makefile
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Fixed-point audio codecs often use saturating arithmetic, and
special instructions for these operations are common.
Signed-off-by: Mans Rullgard <mans@mansr.com>
* qatar/master:
fate: add dxtory test
adx_parser: rewrite.
adxdec: Validate channel count to fix a division by zero.
adxdec: Do not require extradata.
cmdutils: K&R reformatting cosmetics
alacdec: implement the 2-pass prediction type.
alacenc: implement the 2-pass prediction type.
alacenc: do not generate invalid multi-channel ALAC files
alacdec: fill in missing or guessed info about the extradata format.
utvideo: proper median prediction for interlaced videos
lavu: bump lavu minor for av_popcount64
dca: K&R formatting cosmetics
dct: K&R formatting cosmetics
lavf: flush decoders in avformat_find_stream_info().
win32: detect number of CPUs using affinity
Add av_popcount64
snow: Restore three mistakenly removed casts.
Conflicts:
cmdutils.c
doc/APIchanges
libavcodec/adx_parser.c
libavcodec/adxdec.c
libavcodec/alacenc.c
libavutil/avutil.h
tests/fate/screen.mak
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Casting the left-most byte to unsigned avoids an undefined
result of the shift by 24 if bit 7 is set. This affects
the rm demuxer.
Signed-off-by: Mans Rullgard <mans@mansr.com>
* qatar/master:
doxygen: Consistently use '@' instead of '\' for Doxygen markup.
Use av_printf_format to check the usage of printf style functions
Add av_printf_format, for marking printf style format strings and their parameters
ARM: enable thumb for Cortex-M* CPUs
nsvdec: Propagate error values instead of returning 0 in nsv_read_header().
build: remove SRC_PATH_BARE variable
build: move basic rules and variables to main Makefile
build: move special targets to end of main Makefile
lavdev: improve feedback in case of invalid frame rate/size
vfwcap: prefer "framerate_q" over "fps" in vfw_read_header()
v4l2: prefer "framerate_q" over "fps" in v4l2_set_parameters()
fbdev: prefer "framerate_q" over "fps" in device context
bktr: prefer "framerate" over "fps" for grab_read_header()
ALSA: implement channel layout for playback.
alsa: support unsigned variants of already supported signed formats.
alsa: add support for more formats.
ARM: allow building in Thumb2 mode
Conflicts:
common.mak
doc/APIchanges
libavcodec/vdpau.h
libavdevice/alsa-audio-common.c
libavdevice/fbdev.c
libavdevice/libdc1394.c
libavutil/avutil.h
Merged-by: Michael Niedermayer <michaelni@gmx.at>
* qatar/master:
swscale: properly inline bits/endianness in yuv2yuvX16inC().
(We didnt pull the bug) swscale: fix clipping of 9/10bit YUV420P.
Add av_clip_uintp2() function
(our patch / duplicate) dfa: fix buffer overflow checks to avoid integer overflows.
(our patch / duplicate) movenc: always write esds descriptor length using 4 bytes.
(our patch / duplicate) ffmpeg: use parse_number_and_die() when it makes sense
(No thanks) ffmpeg: get rid of the 'q' key schizofrenia
Merged-by: Michael Niedermayer <michaelni@gmx.at>
On some versions of gcc, these weren't always getting inlined due to hitting
the inline cap limit in some files. This is generally bad, as most of these
functions are smaller inlined than not.
(cherry picked from commit eb3755a5aa)
On some versions of gcc, these weren't always getting inlined due to hitting
the inline cap limit in some files. This is generally bad, as most of these
functions are smaller inlined than not.
