-
HDV in After Effects CS3 – black screen
Hello everybody,
I experience some strange problem, I shot with a Sony-FX1 some HDv footage and captured it with Final Cut 5 and with my Powerbook which runs OSX 10.3.9 and Quicktime 7.4
I had no problem, I was able to watch the footage.
Now I transfered all to an iMac (OSX 10.5 / QT 7.4) to work with it and all I get in After Effects is a black screen, but I can hear Sound, when I open it with QT I have a white Screen with sound and when I open it in Final Cut 5 on the iMac it is working fine and I can watch the footage….does anybody know what the problem is here?Thanks,
Stephan
-
6 Replies
-
A white screen is usually indicative that your system is missing the proper codec to properly play the file. Since your second system doesn’t have FCP installed it is probably missing the codec that FCP used when you captured the footage.
It is best when working with HDV footage and AE to convert the footage into a lossless format. HDV uses “long GOP” MPEG-2 compression which can be difficult to work with efficiently in AE.
Erik
-
Thanks for the reply, if it is the best, then I will convert it. As for understanding, can you say in a short sentence why it is not so good to work with long GOP Mpeg2-compression?
Also I want to add, that I have FCP installed on the second system, this is what is so strange about it, that it works in FCP but not AFX.
stephan
-
There are several reasons for not working in HDV. Since HDV is MPEG-2 it is compressed using intraframe compression, meaning that not every frame of video is a full frame of video, rather some are full frames followed by frames that only include changes that have occurred. During the decoding (playback) process these partial frames refer to the full frames (I-frames) to then display a complete frame of video. This decoding process is more taxing on the computer since it has to do a lot of overhead processing to create frames of video in order to display and work with them.
When you convert the footage to a lossless codec, you are decoding this compressed video once and creating full frames of video for every frame. The file size of the video will be much much larger, but it will be easier to work with and not cause the system to do additional processing.Erik
-
ok, thank you very much for this information!
-
You really don’t want to work in HDV for the reasons outlined above. I’ve had great luck converting HDV to ProRes 422 on import. It’s not lossless but it is an excellent codec with a high bit rate which generates reasonably sized files. I highly recommend it.
Arthur
Arthur Vibert
-
I have another question:
I downloaded the Blackmagic codec and it gives me the
possibility to render out the hdv footage with 10bit.
Does it make sense to do so, or should I just use the 8bit?thanks,
stephan
Reply to this Discussion! Login or Sign Up