asfdec: substract preroll time from marker presentation time

this was forgotten when we changed ASF to not output the preroll time

Signed-off-by: Vladimir Pantelic <vladoman@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
asfdec: replace magic constant with DATA_HEADER_SIZE

Signed-off-by: Vladimir Pantelic <vladoman@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
asfenc: add ASF_Reserved_4 as defined in section 10.10 of the ASF spec

Signed-off-by: Vladimir Pantelic <vladoman@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
asfenc: remember send time and offset of the index entries

Signed-off-by: Vladimir Pantelic <vladoman@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
asfenc: mux chapters in ASF files using an ASF "marker" section

ASF markers only have a start time, so we lose the chapter end times,
but that is ASF for you

Signed-off-by: Vladimir Pantelic <vladoman@gmail.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>