After Effects and Matrox MPEG2 I-frame

[rgoliveira]

Hello,

I am experiencing an issue when exporting from Adobe Effects using the codec Matrox MPEG2 I-frame. The same is happening with Matrox MPEG2 I-frame HD, both with or without alpha channel. No matter the data rate I set, it's always encoding at a much higher data rate. For example, I just encoded a 15s video (plus audio and alpha channel) for which I've set to 25 Mbps, but it resulted in a 714 MB file. It's about 380 Mbps, too far away from the 25 Mbps I've set. I remember that some time ago I did the same and the result was a fairly small file, easily handled by Adobe Premiere and because that, this was the format of choice to export compositions to work with Adobe Premiere when alpha channel is required (MXF is used when don't need alpha channel).
It's seems to me it is actually not using Matrox MPEG2 I-frame, but uncompressed instead.
On Adobe Premiere Pro it's working fine.

Am I missing something?

The setup:

Windows 7 SP1
Adobe After Effects CS5.5 (fully updated)
Matrox MXO2 Rack
Matrox Utils 6.1.0.99
Nvidia Quadro 5000 (driver version 296.70, updated today, but have this issue with version 276.42 too).

I did the same tests on the laptop using the Matrox VFW software codecs version 1.0 (build 33) and resulted the same.

Thanks for any help or advice you can provide.

Kind Regards,

Roberio

[Matrox_Support_Sam]

Hi Roberio,

We have tested this in house and we are not able to replicate your issue.
The AE exported Mpeg2 file sizes are correct depending on the data rate selected within AE.

Can you specify your workflow steps so we can troubleshoot the issue here?
What is the source file you are using for export to Matrox Mpeg2 Iframe?

Can you confirm the data rate selected is updated once you click OK in the Codec Setting in AE Export settings?

We await your results.
_________________
Regards,
Sam
Matrox Video Technical Support