Recherche avancée

Sur d’autres sites (4011)

• Make better marketing decisions with attribution modeling

  19 décembre 2017, par InnoCraft — Community, Plugins

  Do you suspect some traffic sources are not getting the rewards they deserve ? Do you want to know how much credit each of your marketing channel actually gets ?

  When you look at which referrers contribute the most to your goal conversions or purchases, Piwik shows you only the referrer of the last visit. However, in reality, a visitor often visits a website multiple times from different referrers before they convert a goal. Giving all credit to the referrer of the last visit ignores all other referrers that contributed to a conversion as well.

  You can now push your marketing analysis to the next level with attribution modeling and finally discover the true value of all your marketing channels. As a result, you will be able to shift your marketing efforts and spending accordingly to maximize your success and stop wasting resources. In marketing, studying this data is called attribution modeling.

  Get the true value of your referrers

  Attribution is a premium feature that you can easily purchase from the Piwik marketplace.

  Once installed, you will be able to :

  • identify valuable referrers that you did not see before
  • invest in potential new partners
  • attribute a new level of conversion
  • make this work very easily by filling just a couple of form information

  Identify valuable referrers that you did not see before

  You probably have hundreds or even thousands of different sources listed within the referrer reports. We also guess that you have the feeling that it is always the same referrers which are credited of conversions.
  Guess what, those data are probably biased or at least are not telling you the whole story.
  Why ? Because by default, Piwik only attributes all credit to the last referrer.

  

  It is likely that many non credited sources played a role in the conversion process as well as people often visit your website several times before converting and they may come from different referrers.

  This is exactly where attribution modeling comes into play. With attribution modeling, you can decide which touchpoint you want to study. For example, you can choose to give credit to all the referrers a single visitor came from each time the user visits your website, and not only look at the last one. Without this feature, chances are, that you have spent too much money and / or efforts on the wrong referrer channels in the past because many referrers that contributed to conversions were ignored. Based on the insights you get by applying different attribution models, you can make better decisions on where to shift your marketing spending and efforts.

  Invest in potential new partners

  Once you apply different attribution models, you will find out that you need to consider a new list of referrers which you before either over- or under-estimated in terms of how much they contributed to your conversions. You probably did not identify those sources before because Piwik shows only the last referrer before a conversion. But you can now also look at what these newly discovered referrers are saying about your company, looking for any advertising programs they may offer, getting in contact with the owner of the website, and more.

  Apply up to 6 different attribution models

  By default, Piwik is attributing the conversion to the last referrer only. With attribution modeling you can analyze 6 different models :

  • Last Interaction : the conversion is attributed to the last referrer, even if it is a direct access.
  • Last Non-Direct : the conversion is attributed to the last referrer, but not in the case of a direct access.
  • First Interaction : the conversion is attributed to the first referrer which brought you the visit.
  • Linear : whatever the number of referrers which brought you the conversion, they will all get the same value.
  • Position Based : first and last referrer will be attributed 40% each the conversion value, the remaining 60% is divided between the rest of the referrers.
  • Time Decay : this attribution model means that the closer to the date of the conversion is, the more your last referrers will get credit.

  Those attribution models will enable you to analyze all your referrers deeply and increase your conversions.

  Let’s look at an example where we are comparing two models : “last interaction” and “first interaction”. Our goal is to identify whether some referrers that we are currently considering as less important, are finally playing a serious role in the total amount of conversions :

  

  Comparing Last Interaction model to First Interaction model

  Here it is interesting to observe that the website www.hongkiat.com is bringing almost 90% conversion more with the first interaction model rather than the last one.

  As a result we can look at this website and take the following actions :

  • have a look at the message on this website
  • look at opportunities to change the message
  • look at opportunities to display extra marketing messages
  • get in contact with the owner to identify any other communication opportunities

  The Multi Channel Attribution report

  Attribution modeling in Piwik does not require you to add any tracking code. The only thing you need is to install the plugin and let the magic happen.
  Simple as pie is the word you should keep in mind for this feature. Once installed, you will find the report within the goal section, just above the goals you created :

  

  The Multi Attribution menu

  There you can select the attribution model you would like to apply or compare.

  Attribution modeling is not just about playing with a new report. It is above all an opportunity to increase the number of conversions by identifying referrers that you may have not recognized as valuable in the past. To grow your business, it is crucial to identify the most (and least) successful channels correctly so you can spend your time and money wisely.

  Learn more about Multi Channel Conversion Attribution

• Why is ffmpeg linking with too many libraries ?

  2 décembre 2020, par Thomas

  I'm trying to build ffmpeg shared libraries for decoding video on Linux systems. The build is done on Arch Linux but the resulting shared libraries need to be as portable as possible.

  


  Fortunately, the functionality built into ffmpeg is sufficient, so I don't want to link with any libraries that might or might not be present on the target system. I'm taking libvdpau as an example of an unwanted dependency here, but there are many more.

  


  Here's what I tried :

  


  $ git clone https://git.ffmpeg.org/ffmpeg.git --branch n4.3.1 --depth 1
$ cd ffmpeg
$ mkdir build
$ cd build
$ ../configure \
    --enable-shared \
    --disable-programs --disable-doc \
    --disable-avdevice --disable-postproc --disable-avfilter \
    --disable-autodetect
$ make -j9


  


  Notice --disable-autodetect which should prevent autodetection of which dependencies happen to be present on the build system.

  


  And yet, when I check the resulting libraries, all of them have dependencies that I didn't ask for. For example :

  


  $ ldd libavcodec/libavcodec.so
    linux-vdso.so.1 (0x00007ffcd73cd000)
    libswresample.so.3 => /usr/lib/libswresample.so.3 (0x00007fba1e45c000)
    libavutil.so.56 => /usr/lib/libavutil.so.56 (0x00007fba1e1a7000)
    libm.so.6 => /usr/lib/libm.so.6 (0x00007fba1e061000)
    libpthread.so.0 => /usr/lib/libpthread.so.0 (0x00007fba1e03f000)
    libc.so.6 => /usr/lib/libc.so.6 (0x00007fba1de76000)
    libsoxr.so.0 => /usr/lib/libsoxr.so.0 (0x00007fba1ddf4000)
    libva-drm.so.2 => /usr/lib/libva-drm.so.2 (0x00007fba1dded000)
    libva.so.2 => /usr/lib/libva.so.2 (0x00007fba1ddc0000)
    libva-x11.so.2 => /usr/lib/libva-x11.so.2 (0x00007fba1ddb8000)
    libvdpau.so.1 => /usr/lib/libvdpau.so.1 (0x00007fba1ddb3000)     <- Why is this here?
    libX11.so.6 => /usr/lib/libX11.so.6 (0x00007fba1dc72000)
    libdrm.so.2 => /usr/lib/libdrm.so.2 (0x00007fba1dc5d000)
    libmfx.so.1 => /usr/lib/libmfx.so.1 (0x00007fba1dc4d000)
    libdl.so.2 => /usr/lib/libdl.so.2 (0x00007fba1dc47000)
    /usr/lib64/ld-linux-x86-64.so.2 (0x00007fba1f971000)
    libgomp.so.1 => /usr/lib/libgomp.so.1 (0x00007fba1dc06000)
    libXext.so.6 => /usr/lib/libXext.so.6 (0x00007fba1dbf1000)
    libXfixes.so.3 => /usr/lib/libXfixes.so.3 (0x00007fba1dbe8000)
    libxcb.so.1 => /usr/lib/libxcb.so.1 (0x00007fba1dbbc000)
    libstdc++.so.6 => /usr/lib/libstdc++.so.6 (0x00007fba1d9df000)
    libgcc_s.so.1 => /usr/lib/libgcc_s.so.1 (0x00007fba1d9c5000)
    libXau.so.6 => /usr/lib/libXau.so.6 (0x00007fba1d9c0000)
    libXdmcp.so.6 => /usr/lib/libXdmcp.so.6 (0x00007fba1d9b8000)


  


  I also tried listing all disable flags explicitly, such as --disable-vdpau, but this didn't change anything ; libvdpau.so.1 is still listed in ldd output.

  


  Maybe they are just being linked, but not actually used ? readelf -d seems to point in that direction :

  


  $ ls */*.so
libavcodec/libavcodec.so    libavutil/libavutil.so          libswscale/libswscale.so
libavformat/libavformat.so  libswresample/libswresample.so
$ readelf -d */*.so | grep 'Shared library:' | sort -u
 0x0000000000000001 (NEEDED)             Shared library: [libavcodec.so.58]
 0x0000000000000001 (NEEDED)             Shared library: [libavutil.so.56]
 0x0000000000000001 (NEEDED)             Shared library: [libc.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libm.so.6]
 0x0000000000000001 (NEEDED)             Shared library: [libpthread.so.0]
 0x0000000000000001 (NEEDED)             Shared library: [libswresample.so.3]


  


  This is a nice and tight set of dependencies, the way I actually want them to be.

  


  So maybe the build system is stupid and always adds all detected libraries to the linker command line anyway ? To suppress this, I tried adding --extra-ldflags=-Wl,--as-needed, but that doesn't seem to have any effect either.

  


  The resulting linker command line looks like this (abridged) :

  


  $ make -n libavcodec/libavcodec.so.58
gcc \
    -shared \
    -Wl,-soname,libavcodec.so.58 \
    -Wl,-Bsymbolic \
    -Wl,--version-script,libavcodec/libavcodec.ver \
    -Llibavcodec -Llibavdevice -Llibavfilter -Llibavformat -Llibavresample -Llibavutil -Llibpostproc -Llibswscale -Llibswresample \
    -Wl,--as-needed \
    -Wl,-z,noexecstack \
    -Wl,--warn-common \
    -Wl,-rpath-link=:libpostproc:libswresample:libswscale:libavfilter:libavdevice:libavformat:libavcodec:libavutil:libavresample \
    -Wl,--as-needed \
    -o libavcodec/libavcodec.so.58 \
    [...all .o files...] \
    -lswresample -lavutil -pthread -lm -lm -pthread -lm


  


  It looks like -Wl,--as-needed was already added anyway.

  


  Interestingly, -Llibavdevice is also listed, even though I passed --disable-avdevice --disable-postproc --disable-avfilter to the configure script. That might be a clue : it would pick up my system's libavdevice, which of course comes with far more dependencies. Still I'd expect -Wl,--as-needed to trim these unbuilt dependencies out as well.

  


  Where do these dependencies come from, and how do I get rid of them ?

  


• Compiling FFMPEG with x265 has ERROR : x265 not found using pkg-config

  23 mars 2023, par timweiliu

  At first, I have a project with ffmpeg build support x264 for android in Mac OS.

  



  Now, I want to add x265 support.

  



  I have compiled the x265 with make & make install like this :

  



  [ 81%] Built target x265-static
[100%] Built target cli
Install the project...
-- Install configuration: "Release"
-- Up-to-date: /usr/local/lib/libx265.a
-- Up-to-date: /usr/local/include/x265.h
-- Up-to-date: /usr/local/include/x265_config.h
-- Up-to-date: /usr/local/lib/pkgconfig/x265.pc
-- Up-to-date: /usr/local/bin/x265


  



  and then, I run this shell script :

  



  make distclean 

NDK_PATH=$NDK_HOME
NDK_ARM_PATH=${NDK_PATH}/platforms/android-9/arch-arm
NDK_ARM_BIN_PATH=${NDK_PATH}/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64/bin

CC=${NDK_ARM_BIN_PATH}/arm-linux-androideabi-gcc

chmod +x configure
chmod +x version.sh

if [ $APP_ABI = "armeabi-v7a" ]; then
LOCAL_CFLAGS="-O3 -DANDROID -fpic -I/usr/local/include -march=armv7-a -mfloat-abi=softfp -mfpu=neon"
ABLES="--enable-asm --enable-thumb --enable-hwaccels --cpu=armv7-a --enable-neon"
elif [ $APP_ABI = "armeabi" ]; then
LOCAL_CFLAGS="-O3 -DANDROID -fpic -I/usr/local/include"
ABLES="--disable-neon"
fi
echo $LOCAL_CFLAGS
echo $ABLES
echo $PKG_CONFIG_PATH

echo "开始configure"
./configure \
--disable-yasm \
--disable-debug \
--disable-doc \
--disable-ffmpeg \
--disable-ffprobe \
--disable-ffplay \
--disable-ffserver \
--disable-stripping \
--disable-avdevice \
--disable-postproc \
--disable-network \
--enable-pthreads \
--enable-small \
--disable-encoders \
--enable-encoder=libx264 \
--enable-encoder=libfdk_aac \
--enable-libx265 \
--pkg-config-flags="--static" \
...

echo "开始make"
make -j4

echo "开始install"
sudo make install


  



  It results in an error :

  



  -O3 -DANDROID -fpic -I/usr/local/include -march=armv7-a -mfloat-abi=softfp -mfpu=neon
--enable-asm --enable-thumb --enable-hwaccels --cpu=armv7-a --enable-neon
/usr/local/lib/pkgconfig
开始configure
ERROR: x265 not found using pkg-config


  



  I looked at the config.log :

  



  use_pkg_config x265 x265.h x265_api_get
check_pkg_config x265 x265.h x265_api_get
false --exists --print-errors x265
ERROR: x265 not found using pkg-config


  



  but, the file of x265.pc is existing on the path. Its content is :

  



  prefix=/usr/local
exec_prefix=${prefix}
libdir=${exec_prefix}/lib
includedir=${prefix}/include

Name: x265
Description: H.265/HEVC video encoder
Version: 0.0
Libs: -L${libdir} -lx265
Libs.private: -lstdc++ -lm -lgcc -ldl -lgcc -ldl
Cflags: -I${includedir}


  



  and the x265.h is in include path too.

  



  I run

  



  pkg-config --list-all


  



  It also finds x265 :

  



  TIMWEILIU-MC0:libSrc timweiliu$ pkg-config --list-all
libecpg_compat libecpg_compat - PostgreSQL libecpg_compat library
fdk-aac        Fraunhofer FDK AAC Codec Library - AAC codec library
apr-1          APR - The Apache Portable Runtime library
apr-util-1     APR Utils - Companion library for APR
libpq          libpq - PostgreSQL libpq library
libpcre        libpcre - PCRE - Perl compatible regular expressions C library with 8 bit character support
libpgtypes     libpgtypes - PostgreSQL libpgtypes library
libecpg        libecpg - PostgreSQL libecpg library
x264           x264 - H.264 (MPEG4 AVC) encoder library
x265           x265 - H.265/HEVC video encoder
libpcreposix   libpcreposix - PCREPosix - Posix compatible interface to libpcre
libiodbc       iODBC - iODBC Driver Manager


  



  Now, I don’t know why it does not work.
Why does pkg-config still not find the x265 ?