[gst-devel] Simple example of a video filter
michalk at awpi.com
Thu Feb 3 00:09:35 CET 2011
On 02/02/2011 12:58 AM, Aki Suihkonen wrote:
> The effectv filters in gst-plugins good may form the starting
> point you need; Even though they don't implement anything
> particularly advanced, such as dealing with different
> input/output rates, different input/output formats or frame sizes,
> they still contain a rather big amount of interfaces and glue
> to the gstreamer infrastructure.
> You would basically have to locate the function
> xxxx_transform( GstBaseTransform *trans, GstBuffer *in, GstBuffer *out)
> and write your transform function inbetween the LOCK/UNLOCK statements.
> such as
> for (i=0;i<number_of_y_pixels;i++) *dst++=*src++ + 1;
> (or + 0x40 to actually see a difference)
> The extra stuff is basically there to parse the caps / mimetypes
> and get the necessary formats/widths/heights in order to know
> how many bytes to process.
Thanks. That helped a lot.
Now, I am having problems with unresolved symbols.
I am referencing some functions in video.c, but when I run gst-launch,
it says those symbols are missing. I can comment out the functions, and
my element behaves just fine.
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