GStreamer-1.0 omxh264dec output color space format

[Lazar Todic]

Hi everyone. I'm trying to write simple video filter in GStreamer-1.0. My filter is linked after omxh264dec. In order to access the wanted pixels(bytes) in correct order in buffer I need to know what is the output color space format of the omxh264dec decoder. I think I expressed myself correctly, please don't mind if I'm wrong, I'm relatively new to GStreamer. When launching gst-inspect-1.0 omxh264dec I see that source pad receives video/x-raw. Does this mean that it supports any x-raw format, NV12, YUV420 etc? I need to work with data in NV12 format. If I use this pipeline can I expect that the color space format is NV12?

pipeline:
gst-launch-1.0 filesrc location=out.mpg ! tsdemux ! h264parse ! omxh264dec ! video/x-raw, format=NV12 ! videoconvert ! colorfilter ! nveglglessink -e

Thanks in advance!

[Sebastian Dröge-3]

On Mi, 2016-06-15 at 02:08 -0700, Lazar Todic wrote:

> Hi everyone. I'm trying to write simple video filter in GStreamer-1.0. My
> filter is linked after omxh264dec. In order to access the wanted
> pixels(bytes) in correct order in buffer I need to know what is the output
> color space format of the *omxh264dec* decoder. I think I expressed myself
> correctly, please don't mind if I'm wrong, I'm relatively new to GStreamer.
> When launching *gst-inspect-1.0 omxh264dec* I see that source pad receives
> video/x-raw. Does this mean that it supports any x-raw format, NV12, YUV420
> etc? I need to work with data in *NV12* format. If I use this pipeline can I
> expect that the color space format is NV12?
>
> pipeline:
> gst-launch-1.0 filesrc location=out.mpg ! tsdemux ! h264parse ! omxh264dec !
> video/x-raw, format=NV12 ! videoconvert ! colorfilter ! nveglglessink -e

The caps you see in gst-inspect-1.0 are only all possibilities. At
runtime your colorfilter element will have to look at the caps that it
is receiving in the CAPS event. And based on that decide what to do.

For parsing raw video caps there is GstVideoInfo, which might be
helpful for you. Or depending on what kind of base class your filter
uses, there might also be simple ways of handling this.

--

Sebastian Dröge, Centricular Ltd · http://www.centricular.com

_______________________________________________
gstreamer-devel mailing list
[hidden email]
https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel