[gst-devel] The 1.0 plan

[Stefan Kost]

Am 03.12.2010 21:36, schrieb wally_bkg:
> 
> 
> Sebastian Dröge-7 wrote:
>>
>> On Fri, 2010-12-03 at 09:09 -0800, wally_bkg wrote:
>>
>>> I also think the best documentation is a working sample code, with decent
>>> comments.  The only way I could figure out how to interpret video data
>>> pixels in a buffer (either as a plugin or appsink) was to stumble around
>>> the
>>> source code for gstgamma and gstvideoscale.  
>>>
>>> Of course the data you get in a buffer depends on the caps, but am I the
>>> only one who thinks there has to be a better way than:
>>>
>>> [...]
>>
>> For this you should use the libgstvideo API to get the video format,
>> width, height, rowstride, component widths/heights, component offsets,
>> pixel strides, etc. from the caps:
>> http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-base-libs/html/gst-plugins-base-libs-gstvideo.html
>>
>>
> 
> Actually it was the nested function call to get the caps that seemed goofy
> to me.   I still need to do that on the buffer to use most of these API
> functions.

structure = gst_caps_get_structure (gst_buffer_get_caps(buf), 0);

well read the docs, and you'll see that caps can have multimple structure
entries (you specify 0 to get the first entry).

> 
> Unfortunately not all the API features I might like to use are in the 10.28
> version that is in Ubuntu 10.04.  Since I don't intend to maintain a
> distribution, I need to target something as a lowest common denominator (it
> was Ubuntu 8.04 when I first started learning about gstreamer).

You can use the GStreamer developer PPA to have the latest releases on ubuntu.
https://launchpad.net/~gstreamer-developers/+archive/ppa

> 
> I'm still trying to decide if overall my problem is better solved by
> processing the video data by writing a plugin or using appsink & appsrc. 
> I'm playing around right now with both approaches, but straight off the top
> using appsink & appsrc lets me create my application with a simple make file
> instead of needing all the automake stuff to build a plug in.  Once I'd
> built the plugin template the first time,  "make" was all I needed
> afterwards, but I'd sure hate to have start with virgin Ubuntu install, and
> the one file I modified for my "plugin" and have to show someone else how to
> build and install it again!
>  

Maybe lets discuss this in a separate thread :)

Stefan