[Vorbis-dev] base64 ALBUMART vorbiscomment (was Re: [ogg-dev] Ogg/Spots and Ogg/MNG)

[Ian Malone]

Conrad Parker wrote:
> On 13/04/2008, Ian Malone <ibmalone at gmail.com> wrote:
>> Ivo Emanuel Gonçalves wrote:

> 
>> You can't with vorbiscomment (you have to dump the comments, strip it
>>  and write them back, and vorbiscomment will not support safe
>>  round-tripping if I recall correctly, due to the new-line thing).
> 
> Ian, could you clarify this?
> 

As far as I remember, quite a while ago, I asked about having '\n' in 
comments (at the time I used quite extensive COMMENT= tags). If you pipe 
vorbiscomment's output to a file and then use the -wc options to write 
that comment back you hit the problem that it reads line-by-line.

And you can't over-write comments unless you use -w, as multiple 
comments with the same name are allowed.

>>  You can do it with the comment library.
> 
> which comment library are you thinking of?
> 

The vcedit that vorbiscomment is based on should make it relatively 
easy, but you do have to rewrite that bit of the stream if you want to 
do it.  Liboggz can do it too of course.

I am talking about two different things I realise, there's how easy it 
is for a programmer to work with it and how easy an end user will find 
it. (And at the end of the day I assume people will want to do this with 
a GUI.)

>>  So for a developer I think it's
>>  harder to add/subtract images that are already Ogg encapsulated as you
>>  just use liboggz or your own muxing (the already encapsulated is the
>>  tricky bit).
> 
> I don't understand this sentence :-) are you saying that one of the
> possible approaches is lacking in library/tool support?
> 

What's needed is a tool to encode png / jpeg to OggMNG (Can rillian's 
experimental code do that?  A while since I've checked.), and another to 
demux back to something that can be passed to libpng / a jpeg library, 
without the time based aspect (for this particular application).  If 
those things already exist then this is already done isn't it?

-- 
imalone