1.0 Installation the backends 3gp converter was written in kommander scripting language so you will need Kommander installed at your system (at least kommander-executor).Kommander is a part of kde-webdev package,so you should install this package to use this script,or you can downolad source code of
Kommander, then compile and install.You can find the full sources (kommander editor/executor) at the the home page,but kommander executor only sources is also avalible.
Also you need
FFmpeg, that must be compiled with AMR audio-codec support for this to work.
Extract ffmpeg sources in some directory,
create new directory inside ffmpeg tree /ffmpeg_source_dir/libavcodec/amrwb_float
then download AMR_WB
sources
and extract AMR_WB sources in amrwb_float directory.
Then downlodad AMR_NB
sources
create new directory inside ffmpeg tree /ffmpeg_source_dir/libavcodec/amr_float
and extract AMR_NB sources at amr_float directory.
You must configure at least with options --enable-amr_nb --enable-amr_wb
If you are planing to encode videos with AAC sound,then you must have
libfaac installed at your system and should enable support for that ( --enable-libfaac)
When you are ready to compile,just open the console, configure with needed options,compile and install ffmpeg.
(f.e. ./configure --enable-amr_nb --enable-amr_wb --enable-libfaac && make && make install)
It you want to enable some other extra codecs for ffmpeg,then type ./configure --help for all list.
Optionally you can compile mplayer with AMR codecs support (you must recompile it if you have mplayer already installed at your system withous AMR support) ,to prevew converted video/audio clips with sound.At first download the latest version of
Mplayer source code.Then extract it in some directory,create new directory inside mplayer tree /mplayer_source_dir/libavcodec/amrwb_float then download AMR_WB
sources and extract in amrwb_float directory.Create new directory inside mplayer tree /mplayer_source_dir/libavcodec/amr_float ,then downlodad AMR_NB
sources and extract it in amr_float directory.After that,configure compile and install as always.
1.1 Using the script If you downloaded distro-independent tarball then just extract it and run from the console $kmdr-executor 3gp-comverter-XX.kmdr.If you downloaded package for your distro (rpm:Red-Hat/Ferora,Suse,Mandriva or tgz:Slackware,Vector,KateOS) then install the package and search the link in the K menu.When the main window opens you , choose the input and output files and tune up all needed parameters:select video codec h.263 or mpeg4 depening on your mobile phone model.Keep in mind that h.263 codec is supported by most mobile phones,use mpeg4 codec only if you are sure that your mobile phone can decode it.Choose the resolution of the picture.If you want to set up custom resolution remember that h.263 codec has fixed valid resolutions (128x96, 176x144, 352x288, 704x576, and 1408x1152) and if you will try to set any other resolutions than it wont encode.But there is no such limitations for mpeg4 codec.Also remember that 128x96 and 176x144 are resolutions that supports most mobile phones,and if you will encode the video with mpeg4 codec with any other custom resolutions then probably your mobile phone will not play it.So the next step is setting up framerate and bitrate of the video.I guess 10 fps and 96 kb/s will be fine for most models,setting higher values of these parameters can increase quality of the picture but also increase the file size as well.Also not all models of mobile phones supports higher parameters.You can switch 2 pass encoding to increase quality,but it takes more time to encoding.optiolally you can set up other parameters like cropping of you want.When you done with the video settings you should set up settings for audio stream.If your mobile phone supports AAC then it is best to choose that codec for encoding audio stream.It can produce higher quality that default AMR_NB codec.You shpuld set up the bitrate and samplerate of your audio and of course higher values of these parameters can increase quality of the sound but also increase the file.Optionally you can switch 2 channels (stereo) for the audio stream but,most cheap mobile models do not support stereo sound.If your mobile do not support AAC sound then you should not switch it,and AMR_NB audio codec will be used(default).Most mobiles phones can decode AMR sound.The higheest bit rate for that codec is 12 kb/s,and it is not recomended to decrease it,because you will get very poor quality for audio stream.Also sample rate is set to 8000 Hz and you can not change it because it is the highest value for this codec.You can increase or decrease audio volume ,250 is the default.In the Global Options section of the program you can set up any other parameters if you need it,like file size and time limitations,encoding priority (0 is default) choose the backend for prevew etc.
If you set up all needed parameters then start encoding,you will see the message DONE in the status section when the output file will be ready.Also you can prevew source and ancoded files if you want using FFplay or mplayer.Choose the backend for prevew in Global Optins section.If you do not have mplayer installed at your system use ffplay(default) which is a part of ffmpeg.If you complile mplayer with AMR audio codec support then you will be able to witch encoded clips(if AMR audio codec was used) with sound.
If you have old mobile phone with no video/mp3/aac support then this script can be useful for you to encode AMR only audio.You shoud switch it,choose the input and output audio files and start encode.
Thats it :)