x264 quality / no audio

[hempcow]

I tried to encode a VOB to x264. The preview function shows the movie correctly inclusive audio. Yet, the movie has no audio but there is a separate file with the name "xxx.audio.mp4" with 0 kb.

in audio I use

encode audio = yes
AC3
384kbit
48000hz
stereo
cbr

audio track 1 (since the preview function has audio with track 1 but not with track 0 it must be the correct one. in the VOB file, I ripped only one audio track from the original DVD)

yet, there is no audio. what did I do wrong?


another question regarding video quality:

I used 1400 kbit/s for a resolution of 720x576, but the quality is not perfect (I turned on all improvements, 2 pass encoding, 4x4i, etc.). Should I use a higher bitrate, e.g. 2000 kbit/s. Is there an optimal bitrate for a given number of pixels (e.g. 1 Megapix should have 3000 kbit/s or something like that).


Thanx for your input, especially for the audio problem.......

[Case]

Audio in ffmpegX-generated x264 MP4 files should be AAC. Even if you select AC3, it would override and encode to AAC anyway.

The log should provide clues to the correct audio track. Click the blue "i" to access the log.
The preview uses mplayer, which may be different from your encode, and thus behave differently for an audio track number selection. Especially so for VOBs with 'missing' audio tracks.

All re-encodes will look less perfect, as the output is lossy and perhaps filtered. A higher video bitrate will allow for more visual quality, but the file size increases more than the quality for higher bitrates. The optimum is around 1214 kbps for 720x576 at 25 fps with H.264.
It also depends on your source file. A cleaner image (little noise/grain) can be better compressed/encoded.