Annoying Artifacts
When I do TV capturing with VirtualDub, with the KWorld PCI Analog TV Card Lite (PVR-TV 7134SE) hardware device, the only sampling rate that I could choose for audio compression is 32 KHz, irrespective of the audio compression format. As a consequence, I have to compress my MP3 audio with a sampling rate of 32 KHz - in stereo with a bit rate of 96 Kbps.
I do not get any problems with the audio if I were to view my playbacks on my PC. But for playbacks using a media player that is connected to my TV, I can hear those annoying MP3 artifacts - some funny distortion when someone is talking that is audible at certain parts of the playback. I suppose this is because my TV has better speakers compared with my PC.
Fixing It
To get rid of this annoying MP3 artifacts in my TV captures, I have to do some video editing by converting the MP3 audio of the captured .AVI file to a 44.1 KHz sampling rate (from 32 KHz) via the VirtualDub audio filter "resample". While I am at it, I also include the "lowpass" filter set at 17 KHz (to get rid of any sound that is inaudible to the human ear), and the "gain" filter (as I find the captured audio to be a little soft). I then configured VirtualDub to recompress the audio again into the MP3 format at 44.1 KHz sampling rate and 96 Kbps bit rate in stereo.
To save me from retyping these commands everytime when I need to change the sampling rate, I save all the above mentioned steps into a VirtualDub script (Ctrl-S). I just hit Ctrl-L
Note: I usually perform the audio and video synchronization (see VirtualDub Post Capturing: Keeping Audio And Video In Sync) and this MP3 resampling together in one go. I just have to remember to load the script file, as mentioned above, before I start.
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