[FFmpeg-user] Loss of resolution when adding metadata to an ogv file

[Giordano Lipari]

Hi all! 
Admittedly I am a vanilla ffmpeg user busy with early experimentation work (version 0.8.17-4:0.8.17-0ubuntu0.12.04.1). 
I have read the ffmpeg Documentation but lack the background to fully grasp possibilities, implications and messages in the bottle.

a) My first aim was to add some metadata information to an ogv file with the following command
   ffmpeg -i testIn.ogv -metadata title="test title" testOut.ogvThis was successful, but the quality of the output file worsened a lot. I presume that this is because of a reduction of the fps, which I did not ask though.
b) Then, more specifically, the command
   ffmpeg -i testIn.ogv -metadata year="2015" testOut.ogvwas well received by the console that acknowledged this setting. However the year value never made to the output file. The viewers I tested the output with (Movie Player and Banshee), showed a blank field. The video quality was as bad as in case a)
c) Finally, the command  ffmpeg -i testIn.ogv -r 15 testOut.ogvaimed at solely keeping the same fps rate of the original, but failed to keep the promise.
Questions then:
Any mistakes in conceiving the correct operations to reach the aims (metadata + equal resolution)?Has ogv perhaps special features that make my attempt ill-posed from the outset?Any tips to put me straight on the matter? I will appreciate explanations as I may well be in need of them to hone my intuition.
Thanks in advance.
Cheers,Giordano