f7e187d362
Change Ice204e86 identified a problem with bitrate undershoot due to low precision in the timestamps passed to the library. This patch takes a different approach by calculating the duration of this frame and passing it to the library, rather than using a fixed duration and letting the library average it out with higher precision timestamps. This part of the fix only applies to vpxenc. This patch also attempts to fix the problem for generic applications that may have made the same mistake vpxenc did. Instead of calculating this frame's duration by the difference of this frame's and the last frame's start time, we use the end times instead. This allows the framerate calculation to scavenge "unclaimed" time from the last frame. For instance: start | end | calculated duration ======+=======+==================== 0ms 33ms 33ms 33ms 66ms 33ms 66ms 99ms 33ms 100ms 133ms 34ms Change-Id: I92be4b3518e0bd530e97f90e69e75330a4c413fc |
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build | ||
examples | ||
libmkv | ||
nestegg | ||
tools | ||
vp8 | ||
vpx | ||
vpx_mem | ||
vpx_ports | ||
vpx_scale | ||
.gitattributes | ||
.gitignore | ||
.mailmap | ||
args.c | ||
args.h | ||
AUTHORS | ||
CHANGELOG | ||
configure | ||
docs.mk | ||
example_xma.c | ||
examples.mk | ||
keywords.dox | ||
libs.doxy_template | ||
libs.mk | ||
LICENSE | ||
mainpage.dox | ||
md5_utils.c | ||
md5_utils.h | ||
PATENTS | ||
README | ||
solution.mk | ||
tools_common.c | ||
tools_common.h | ||
usage_cx.dox | ||
usage_dx.dox | ||
usage.dox | ||
vp8_api1_migration.txt | ||
vpxdec.c | ||
vpxenc.c | ||
wince_wmain_adapter.cpp | ||
y4minput.c | ||
y4minput.h |
vpx Multi-Format Codec SDK README - 19 May 2010 Welcome to the WebM VP8 Codec SDK! COMPILING THE APPLICATIONS/LIBRARIES: The build system used is similar to autotools. Building generally consists of "configuring" with your desired build options, then using GNU make to build the application. 1. Prerequisites * All x86 targets require the Yasm[1] assembler be installed. * All Windows builds require that Cygwin[2] be installed. * Building the documentation requires PHP[3] and Doxygen[4]. If you do not have these packages, you must pass --disable-install-docs to the configure script. [1]: http://www.tortall.net/projects/yasm [2]: http://www.cygwin.com [3]: http://php.net [4]: http://www.doxygen.org 2. Out-of-tree builds Out of tree builds are a supported method of building the application. For an out of tree build, the source tree is kept separate from the object files produced during compilation. For instance: $ mkdir build $ cd build $ ../libvpx/configure <options> $ make 3. Configuration options The 'configure' script supports a number of options. The --help option can be used to get a list of supported options: $ ../libvpx/configure --help 4. Cross development For cross development, the most notable option is the --target option. The most up-to-date list of supported targets can be found at the bottom of the --help output of the configure script. As of this writing, the list of available targets is: armv5te-linux-rvct armv5te-linux-gcc armv5te-symbian-gcc armv5te-wince-vs8 armv6-darwin-gcc armv6-linux-rvct armv6-linux-gcc armv6-symbian-gcc armv6-wince-vs8 iwmmxt-linux-rvct iwmmxt-linux-gcc iwmmxt-wince-vs8 iwmmxt2-linux-rvct iwmmxt2-linux-gcc iwmmxt2-wince-vs8 armv7-linux-rvct armv7-linux-gcc mips32-linux-gcc ppc32-darwin8-gcc ppc32-darwin9-gcc ppc64-darwin8-gcc ppc64-darwin9-gcc ppc64-linux-gcc x86-darwin8-gcc x86-darwin8-icc x86-darwin9-gcc x86-darwin9-icc x86-linux-gcc x86-linux-icc x86-solaris-gcc x86-win32-vs7 x86-win32-vs8 x86_64-darwin9-gcc x86_64-linux-gcc x86_64-solaris-gcc x86_64-win64-vs8 universal-darwin8-gcc universal-darwin9-gcc generic-gnu The generic-gnu target, in conjunction with the CROSS environment variable, can be used to cross compile architectures that aren't explicitly listed, if the toolchain is a cross GNU (gcc/binutils) toolchain. Other POSIX toolchains will likely work as well. For instance, to build using the mipsel-linux-uclibc toolchain, the following command could be used (note, POSIX SH syntax, adapt to your shell as necessary): $ CROSS=mipsel-linux-uclibc- ../libvpx/configure In addition, the executables to be invoked can be overridden by specifying the environment variables: CC, AR, LD, AS, STRIP, NM. Additional flags can be passed to these executables with CFLAGS, LDFLAGS, and ASFLAGS. 5. Configuration errors If the configuration step fails, the first step is to look in the error log. This defaults to config.err. This should give a good indication of what went wrong. If not, contact us for support. SUPPORT This library is an open source project supported by its community. Please please email webm-users@webmproject.org for help.