Hi all,
Still on the topic of file format. I think it could be a good idea to
have a validating dtd for kdenlive: that could help diagnosing
wrongly-formed files and would also be a kind-of-human-readable
documentation for the format: as I couldn't find any in the source tree,
I started making one from mlt-xml.dtd. Do you think it would actually be
useful ?
It seems it shouldn't be too much work. I tried to validate a simple
Kdenlive file against the mlt-xml.dtd and "fixed" the errors of the fly
; I found two categories of issues:
- Adding attributes and children elements, which is straightforward. I
always assumed CDATA for the type (so there is room for optimisation if
we want stricter control: e.g the hide element could have a more
constrained type, I guess). Just a few points that should be addressed :
- In the DTD, Playlist can't be empty, as they must have a least
one of the following elements : (entry | blank | producer | playlist |
property | tractor | multitrack)+. But I get an empty one in my simple
example : which is correct ?
- In the DTD, tractor has a mandatory multitrack child element :
tractor (multitrack, (filter | property | track| transition)*) , but
such child element never appears in my example. Should it be tractor
(multitrack | filter | property | track| transition)+ ?
- ID /IDREF types issues. It seems that most issues related IDs has been
fixed between "Generation 2" and "Generation 3" formats. There is one
remaining, "main bin" as you can't have spaces in IDs
(https://www.w3.org/TR/REC-xml/#NT-Name ). could that be fixed in the
code, or should we give up on the ID/IDREFS types and just use CDATA ?
Cheers,
Camille
