August, Voodoo Lagfix

First generation of Samsung Galaxy S smartphone was released running Android 2.1 Eclair.
Despite leading competition in the specs department, this Android device was suffering from severe pause in OS and application execution, rapidly qualified universally as lag.

Novice in mobile development but comfortable with Linux system administration, but also without a job,  [BOUNTY] Community help is needed for fixing the poor IO performance (lag) of the SGS discussion thread on XDA  caught my attention.
Assuming publishing a fix would take 3 or 4 days I started the “full” approach: replacing offending Samsung proprietary RFS filesystem by Linux standard Ext4.

This first project became eventually a great success, in its technical results but also personally, XDA community donating more than planned initially but more importantly being so supportive so convince me believing my little hacks could be worth something, instead of being forgotten unfinished on my hard drive.

Despite Voodoo lagfix was working very well, RFS <-> Ext4 conversion reliability and strong performance & data safety always being the key points of this solution, a lot of debate happened on XDA on a moot point, Ext4 journaling being accused of premature wear of the NAND memory in FUD talk by the developer of an alternative based on Ext2, looking good in benchmarks but not really solving the lag issue because still depending on RFS.
Eventually debate was sealed by Google adopting Ext4 on Nexus S, officially recommending it as standard for every Android device, Samsung then choosing Ext4 with Voodoo lagfix optimized parameters on Galaxy S II (and all their next android devices).

As the whole Galaxy S generation has been plagued by RFS lag, Vodooo lagfix (source code link) has been ported on many devices, including all Galaxy S US variants (Vibrant, Captivate, Fascinate, Epic 4G) and many more I don’t even know of.

October, Voodoo Sound

Same Samsung Galaxy S had great potential in audio quality thanks to the choice of Wolfson Micro WM8994 audio hub a with a good hardware implementation.

Presentation of a couple of ideas in XDA Thread Anything related to Sound: features or fix requests in order to gain more feedback and generate interest showed that audio was captivating community members, surpassing by far any expectations in a forum dedicated usually to custom ROMs or kernels.

After a few releases depending on flashing a custom patched kernel on the phone, Korean developer tegrak ported Voodoo Sound patches as a Linux kernel module using brilliant rootkit-inspired method as an alternative to complete kernel replacement.
His contribution made a huge difference, by allowing me to release Voodoo Sound Plus as paid app on Google Play store. No job, no money… at that time I had no choice but leave & do something else or succeed.
Luckily the app became successful, allowing me to continue android development ever since!


December, Voodoo LOUDER

Galaxy S successor, massively popular Galaxy S II came with a lot fewer software quirks to fix.
Unfortunately this time Samsung chose to change of Audio Codec for another built by Yamaha: YMU823 aka MC1N2 that might have look good on paper with good SNR and THD theoretical measurements, but unfortunately revealing issues plaguing audio quality once implemented in the actual mobile device.

Analyzing Galaxy S II audio was a great opportunity to start collaborating with Anandtech, as an audio analysis page in their review.

Disappointed, I wasn’t planning hacking Galaxy S II audio until I bought a Galaxy Note, which headphone output levels were very low with the original Gingerbread.
Annoyed by that, I wrote a new driver and application to fix it.
LOUDER support has then been extended to Galaxy Tab 7.7 and Galaxy Tab Plus.
Not using Galaxy S II or Galaxy Note to listen to music myself, this app is not my favorite and is paid-only.


A lot of projects are not cited here, as you will see in the Applications page and on github source code repository