Deleting a video isn’t as easy as removing an image: You have to long-press the video thumbnail in an album. The long-press activates multiple-selection mode. For removing a video, however, just touch the Trash icon that appears in the upper-right corner of the screen. Choose the Confirm Delete command, and the video is gone.
You can’t undelete an image or a video you’ve deleted. There’s no way to recover such an image using available tools on the Galaxy Tab.
You can apply the Delete command to an entire swath of items in the gallery at once. To do so, you must know the secret, found below:
1. Open the album (pile) you want to mess with.
2. Long-press an image to select it.
3. Continue touching images and videos to select them.
Or you can choose the Select All command.
4. Perform an action on the group of images or videos.
To deselect items, touch them again. To deselect everything, touch the Done command.
The type of commands you can use on a group of items in an album depends on the group. Some commands, such as Delete and Share, can be performed on any old group. Other commands, such as the image rotation commands, work only with pictures, not with videos.
See more here:
[http://www.erasephone.com/tutorials/how-to-delete-iphone-photos.html|Delete iphone photos]
[http://www.erasephone.com/tutorials/delete-everything-from-iphone-ipad-ipod.html|Delete everything from iPhone]