Can camcorder Sony HDR CX455 record videos in MP4 at 1920 x 1080i to be uploaded to YouTube?
Finally, I got the official answer from Sony Customer Service as follow:

Yes, You can record MP4 at 1920 x 1080p. Please be advised that the video format for the XAVC S is in MP4, while the AVCHD is for m2ts files. And please make sure that the File Format that is set in your camcorder is XAVC S HD:
- Press Menu.
- Select Image Quality/ Size.
- File Format (film icon) and select  XAVC S HD.

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