[FFmpeg-user] Why doesn't SAR 1:1 DAR 4:3 take effect?

[Phoney at neo.rr.com]

***** Excuse the aborted post.

Help please,

 What's the difference?

 Source:
 Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661),
yuv420p(progressive), 640x480 [SAR 8:9 DAR 32:27], 746 kb/s, 29.97
fps, 29.97 tbr, 30k tbn (default)

 Target:
 Stream #0:0[0x1](und): Video: h264 (High) (avc1 / 0x31637661),
yuv420p(progressive), 640x480 [SAR 1:1 DAR 4:3], 746 kb/s, SAR 8:9 DAR
32:27, 29.97 fps, 29.97 tbr, 30k tbn (default)

 Why does the target have both this:
 "[SAR 1:1 DAR 4:3]"