Return playback URL of the video. This is direct link to the movie
file. Function supports only "fmt" option.
prepare_download($video_id)
Gather data about the video. A hash reference is returned, with the
following keys:
"fmt"
the default, suggested format. It is inferred by selecting the
alternative with the highest resolution.
"fmt_list"
the list of available formats, as an array reference.
"suffix"
the filename extension associated to the default format (see
"fmt" above).
"title"
the title of the video
"user"
the YouTube user owning the video
"video_id"
the video identifier
"video_url"
the URL of the video associated to the default format (see "fmt"
above).
"video_url_map"
an hash reference containing details about all available
formats.
The "video_url_map" has one key/value pair for each available
format, where the key is the format identifier (can be used as "fmt"
parameter for "download", for example) and the value is a hash
reference with the following data:
"fmt"
the format specifier, that can be passed to "download"
"resolution"
the resolution as *width*x*height*
"suffix"
the suffix, providing a hint about the video format (e.g. webm,
flv, ...)