x264 h264 640x272 900kbps 99min, result: small file, blank screen?

[danalog]

Whenever I am trying to convert a file into a file with the settings below I get extremely small files (and blank screens). Resulted files are below 5MB.

x264 h264 iPod
640x272
900kbps
99min

options:
Constant bitrate
Two pass
i4x4
Decode with QT

encoding profile: ipod
Max GOP: 250
Qmin: 15
Qmax: 51
AVC: 3
ME: hexagon

[Case]

900kbps

Seems like a bit much, but that shouldn't be a reason for a failed conversion. Hit the 'Best' button in the Bitrate Calculator for a suggestion by ffmpegX for what bitrate is enough.

Constant bitrate
Two pass

I don't think it makes sense to use both Constant bitrate and Two-pass encoding. Bitrate-wise there is nothing to optimize in the second pass when the bitrate is constant.

Decode with QT

This option requires that the source file is playable in QuickTime. Have you tested that?

[danalog]

Decode with QT

This option requires that the source file is playable in QuickTime. Have you tested that?

That is probably it since the file didn't play in QT at all to begin with ... testing it now.


edit: Now testing, the file is at 10% and the new file is 200KB.. not good.

[danalog]

Ok, now I have a file of about 53MB, with an audio track that plays in QT, but still no video.

Problem only occurs when transcoding from h264, yuv420p, 640x272 to h264 ipod.

[Case]

Ok, what can you tell about your source file? What does ffmpegX's Summary window say about it? Maybe there is a workaround or QT plugin to make your type of files work.

[danalog]

As said the source file is:

mp4
h264
yuv420p
640x272
avc1 (VLC says so)

More, I don't know.

(edit: yes I am trying to convert 264 to 264 because QT/iTunes/iPod does not like the first one so I need iPod optimized version)