multiple processing, or 1-at-a-time?

[coyote2]

Does it matter whether I perform 3 operations at once (i.e. with one "Save As") on a file at the same time, or perform them separately (i.e. with separately, each time doing "Save As").

The operations:

Changing codec from DX50 to XVID
Changing resolution from 720x544 to 640x480
Changing audio (MPEG-1 Layer 3, 48000 tot, Joint Stereo) from 160 kbps to 128 kbps

[jagabo]

Do them all at once.

[coyote2]

Do them all at once.

Since one of the operations I'm planning to do is a 2-pass codec conversion...

Do I leave both of the other operations in place for both passes?

(In other words, if I do so will the resize and bitrate change operations be run more times than is necessary on the final file output?)

[jagabo]

Yes, the video passed to the the encoder should be identical for both passes. During the first pass the encoder is examining each frame of the video for its "compressibility". During the second pass it uses that information to decide how to apportion bits to deliver the average bitrate you requested. It the video is different during the two passes that information may no longer be accurate.

Though I don't know why you're bothering to reencode a 720x540 DX50 video to 640x480 XVID. All you're going to do is reduce the quality. Does the original video use some settings your player can't handle? Are you just looking to make the video smaller?

[coyote2]

Yes, the video passed to the the encoder should be identical for both passes. During the first pass the encoder is examining each frame of the video for its "compressibility". During the second pass it uses that information to decide how to apportion bits to deliver the average bitrate you requested. It the video is different during the two passes that information may no longer be accurate.

Though I don't know why you're bothering to reencode a 720x540 DX50 video to 640x480 XVID. All you're going to do is reduce the quality. Does the original video use some settings your player can't handle? Are you just looking to make the video smaller?

Good question. I'm joining a pair of files with different resolutions.

Thank you for your help, jagabo!