My first android Flash light application as "Power Light"



Power Light 



This application is created for the full utilization of camera flash as torch. It has a special technique for determining hardware and software intensity control mechanism. If the device don't have the hardware intensity control, then this application will fallback to software intensity control. It has camera preview. On camera icon click you can start the camera and on camera window use the floating flash light button for your unreachable area searching.v1.1
Graphics update:
* iPhone style icon.
* Beautiful camera preview button.
* Flashy flash light button.
* Floating button on camera view.
Functional update:
* Live feed from camera.
* Flash on/off in live camera preview.
* All orientation support for camera preview.
* Auto transition from camera preview to main window.

* Light On/Off.
* Intensity Control.
* Hardware Intensity Control.
* Software Intensity Control.

Google's webRTC AECM for Android Mobile devices in C++

Now a days many of mobile devices comes with built-in hardware echo canceler.  But the low end devices that cost little doesn't have this feature integrated. And moreover the previous older android devices doesn't have the echo canceler. In my journey of echo cancellation I have came across a valuable library that will do everything for you , if you provide it the necessary gasoline .

I have tested this echo canceler tool with my HTC desire 610. Which is pretty cheap and doesn't have any built-in hardware echo canceler.  I have designed an algorithm for capture and playback, which uses ring-buffer, calculate the delay and use the webRTC aecm modules API.

Here we go --


    Set the clock cycle rate.
    Set the echo tail length.
    Set the channel count.
    Set the byte per sample. // it's 2 byte per sample


    Calculate sample per frame.
           sampleperframe = byte per sample * (clock cycle rate) / 100

    Set the output latency. // device play-out latecny

    Calculate the frame play delay.
            frameplaydelay = output latency * 3 / 4

    Initiate the webRTC echo module with clock cycle rate.

        Calculate Audio Play time.
            ptime = sampleperframe * 1000 / clock cycle rate

    Calculate latency buffer size.   
            lateframecount = frameplaydelay / ptime

    Add these late frame in latency buffer with filling demo audio data (with zero).


        Store the played frame in the delay buffer (it will be a FIFO ringbuffer
        with your estimated size).

        Now need to remove the demo frame from latency buffer and add real frame
        to the latency buffer.       
        if the latency buffer not filled with real data
                fetch the data from delay buffer and add it to the latency buffer
                and remove it from delay buffer.
            nothing to do.

        if latency buffer not full with real playe frame data
                nothing to do.

            fetch the data from latency buffer and do the echo cancellation by
            setting this frame as far-end and current capture data as the input.
            remove the used frame data from latency buffer.
            if the delay buffer is not empty
                    fetch the frame data from delay buffer and add it to the
                    latency buffer.

                store a demo frame in the latency buffer. 


Make CentOS 6.x an AD member of Windows IIS 2012 R2

Making a CentOS 6.x PC a domain member of an active directory is a tiresome work. I came across this painful task for several time and comes in a conclusion that atleast I will make a document which will be helpful to me in near future. On the meantime if anybody take this step for their use, I wouldn't mind.

So I will go to the task step now --

i) First of all we need some basic (latest) software for making this task possible.
They are --

1. Samba
2. Samba-client
3. Samba-winbind
4. Krb5-workstation
5. Policycoreutils-python

command for the task on console --

yum install -y ntpdate samba samba-client samba-winbind krb5-workstation policycoreutils-python

  ii) Now it's time to make the windows active directory reachable from the centos PC. For that we need to add the active directory FQDN and IP address on resolv.conf

So do it by opening file  /etc/resolv.conf and add the following --

    domain ad.local

if ad.local is pingable from console then our work is done for resolving AD.

 iii) Now we need to sync the time of AD and CentOS PC, so that they can authenticate in kerborus mechanism. It can be done by following --

crontab -e
Now add the following on the opening file --

 0 */4 * * * /usr/sbin/ntpdate >/dev/null 2>&1

Now synchronize the time by --

 We will see the synced time and date on console.

iv) Now we ned to edit the samba configuration file --

    workgroup = AD
    server string = Samba Server Version %v
    security = ads
    realm = AD.LOCAL
    domain master = no
    local master = no
    preferred master = no
    socket options = TCP_NODELAY IPTOS_LOWDELAY SO_RCVBUF=131072 SO_SNDBUF=131072
    use sendfile = true
    idmap config * : backend = tdb
    idmap config * : range = 100000-299999
    idmap config AD : backend = rid
    idmap config AD : range = 10000-99999
    winbind separator = +
    winbind enum users = yes
    winbind enum groups = yes
    winbind use default domain = yeswhen I again have the same issue.
    winbind nested groups = yes
    winbind refresh tickets = yes
    template homedir = /home/%D/%U
    template shell = /bin/bash
    client use spnego = yes
    client ntlmv2 auth = yes
    encrypt passwords = yes
    restrict anonymous = 6
    log file = /var/log/samba/log.%m
    max log size = 50    

v) Edit krb5.conf file for authentication --

    default = FILE:/var/log/krb5libs.log
    kdc = FILE:/var/log/krb5kdc.log
    admin_server = FILE:/var/log/kadmind.log
    default_realm = AD.LOCAL
    ticket_lifetime = 24h
    forwardable = yes
    pam = {
    debug = false
    ticket_lifetime = 36000
    renew_lifetime = 36000
    forwardable = true
    krb4_convert = false
           .ad.local = AD.LOCAL 
            ad.local = AD.LOCAL

vi) Now we update nss configuration file by opening file  /etc/nsswitch.conf .

    passwd: files winbind
    group: files winbind
 We are done.

vii) It's the last step to make centos an AD member of a windows system. Lets over with it by --

 net ads join -U administrator

Will ask for password. Give it and viola!!



[ffmpeg] ffmpeg-2.2 patch for relocation R_X86_64_PC32 against symbol error


ffmpeg-2.2 patch for relocation R_X86_64_PC32 against symbol error when compile in x64-bit

Patch Link:

Download: V1.0

Scope of Issue:

When ffmpeg is built for static library and this compiled static library is linked with another dynamic library then the final linking failed with error --

ffmpeg/libavcodec/libavcodec.a(xx_yyyy.o): relocation R_X86_64_PC32 against symbol `ff_xx_yy_zz_qq' can not be used when making a shared object; recompile with -fPIC
/usr/bin/ld: final link failed: Bad value
collect2: ld returned 1 exit status


x64-bit Linux, Unix, may be windows 64-bit

How to fix:

Use the ffmpeg-2.2.patch in your FFmpeg-n2.2 release source.

How to apply patch:

  1. Copy the downloaded patch to your FFmpeg-n2.2 folder.
  2. Test the patch compatibility with your ffmpeg source by --
patch --dry-run -p1 -i  ffmpeg-2.2.patch
giving this command inside your ffmpeg source folder.
  1. If the test returns no fail patch file then you are good to patch.
  2. Now patch by following command --
patch -p1 -i ffmpeg-2.2.patch
  1. Now enjoy linking with your any other project library !!
Note: I am not in blame for any other issue and any other copyright law , if ffmpeg have any for this. This is only a remedy for the group who suffers from this compilation errors.

[eAskGitHub]Simple C++ console for all github repo release API


Simple console for all github repo release API.


It is a c++ application with a binary. It is created to make the life simple for github repository API user. It uses curl.


1. It can receive any lenght of response from github.
2. It has it's own simple JSON parser method.
3. It is powerfull tool to know your github release download count.
4. Makefile application.


1. Need libcurl.
2. Need Centos/Linux.
3. Not tested with windows(Hopefully it will work after windows curl library installation).


1. Implement every API of [GitHub API](


In console just give command -


Then just follow the hints available on console or answer the querry.

Test Result:


Welcome to github metadata fetcher eAskGitHub v1.0 !!
It's a very simple command line app who will try to
fill your all want for github metadata(THE API).

Please enter github username: robelsharma
Please enter your one repository name: videoconference
Your querry Succeeded :)
Project Title:=>  Chat and Video call simultaneously
Creators' Login Name:=>  robelsharma
User Privilege:=>  User
Are you an Admin for this site?:=> No
Create Date:=>  2014-08-09T08:04:29Z
Publish Date:=>  2014-08-09T08:15:36Z
Project Binary:=>
Uploader Login Name:=>  robelsharma
User Privilege:=>  User
Are you an Admin for this site?:=> No
Binary Package Type:=>  application/zip
|Downloaded: 6 times|
Create Date:=>  2014-08-11T05:50:48Z
Binary Package updated at:=>  2014-08-11T05:50:54Z
Download Link:=>

Want to continue ?(y/n):n