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Christopher Piekarski chris-piekarski

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View gist:852572c81e195b930f297dc79c3df10f
alias randman='dir="/bin"; man $(ls $dir |sed -n "$(echo $(( $RANDOM % $(ls $dir |wc -l | awk "{ print $1; }" ) + 1 )) )p")'
chris-piekarski / build_opencv_ARM_cross
Created Mar 23, 2020 — forked from hrshovon/build_opencv_ARM_cross
Cross compile opencv3.3.0 for your raspberry pi and similar ARM devices with python support
View build_opencv_ARM_cross
This is a note on how to cross compile opencv for pretty much any ARM device(HardFP supported in this case) and deploy. Native
compiling in ARM devices can be painfully slow and they seem to hang often during build(mine got stuck at 43%). So if you happen
to have a desktop/laptop/server running ubuntu or similar linux distro, u can build opencv in fractionth of the time taken for
native compiling without any issues.
Building opencv3 with TBB and NEON and VFP support can boost opencv performance. Thanks to Adrian at pyimagesearch for pointing
that out.
Both my PC and target machine aka orange pi zero are running ubuntu 16.04 with python2.7 and python 3.5.
Let us use the term "build machine" for your PC where you are building opencv and "target machine" for the ARM single board computer.
1.Run the following commands in both machines(I think installing these in target machine only would do) to install the necessary libraries etc.(mine worked with them,so they should be enough
chris-piekarski / pre_commit_reject_wildcard_imports
Created Feb 27, 2019
Git pre-commit hook to check for wildcard imports
View pre_commit_reject_wildcard_imports
# cp to .git/hooks
# chomd +x .git/hooks/pre_commit
# This hook checks for wildcard imports (other than kotlinx) when added to staging.
# TODO: add ktlint check
chris-piekarski / size_up_tensorflow
Created Jan 31, 2019
current line count for tensorflow
View size_up_tensorflow
Python 2.7.12 (default, Nov 12 2018, 14:36:49)
[GCC 5.4.0 20160609] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import rglob
>>> rglob.lcount("/media/chris/UBNT/tensorFlowExample/tensorflow","*.py")
>>> rglob.lcount("/media/chris/UBNT/tensorFlowExample/tensorflow","*.java")
chris-piekarski / basic_file_nano_template
Last active Nov 26, 2018
Using NanoHTTPD in Android
View basic_file_nano_template
Add your index.html file to res/raw
Add dep to app gradle file:
dependencies {
implementation 'org.nanohttpd:nanohttpd-webserver:2.3.1'
Java class file:
import fi.iki.elonen.NanoHTTPD;
View gist:78284318cbad31d7fb92f8200213cec9
#create patches from author(s) into one without comments
#good for GPLv2 sharing
for c in `git log --format=format:%H --author=chris`;do git format-patch --stdout --format=format:%H --no-stat -1 $c;done | tee stuff.patch
View bash_pic_convert
for f in ./*.*;do convert -resize 1280x720 $f ./720p/$f; done
chris-piekarski / repo_grep_logs_by_author
Last active Feb 27, 2018
Grep all AOSP repos commit messages by author
View repo_grep_logs_by_author
repo forall -c git log --grep="partition" --author=Chris
repo forall -c 'echo $REPO_PATH; git log --grep "partition" --author=Chris'
chris-piekarski / git_pull_sub_repos
Last active May 28, 2019
Git Pull Multiple Subdirectory Repos
View git_pull_sub_repos
find . -maxdepth 1 -type d \( ! -name . \) -exec bash -c "cd '{}' && git pull" \;
View cli_vs_filereader
//1ms but uses file cache so not updated quickly
try {
String inputLine;
FileReader file = new FileReader("/sys/class/power_supply/battery/current_now");
BufferedReader bufferedReader = new BufferedReader(file);
inputLine = bufferedReader.readLine();
text = inputLine;
} catch (Exception e) {