Hi all, This RFC discusses the SUBDEV_S_SELECTION/SUBDEV_G_SELECTION API which is intended to amend and replace the existing SUBDEV_[SG]_CROP API. These IOCTLs have previously been discussed in the Cambridge V4L2 brainstorming meeting [0] and their intent is to provide more configurability for subdevs, including cropping on the source pads and composing for a display. The S_SELECTION patches for V4L2 nodes are available here [1] and the existing documentation for the V4L2 subdev pad format configuration can be found in [2]. SUBDEV_[SG]_SELECTION is intended to fully replace SUBDEV_[SG]_CROP in drivers as the latter can be implemented in SUBDEV_[SG]_SELECTION using active CROP target on sink pads. That can be done in v4l2-ioctl.c so drivers only will need to implement SUBDEV_[SG]_SELECTION. If someone is interested in the compose operation on the source pad, I'd like to have better documentation on it. I don't fully understand that use case since I don't use it myself. The original RFC is available in [4]. Questions, comments and thoughts are most welcome. References ========== [0] http://www.mail-archive.com/linux-media@xxxxxxxxxxxxxxx/msg35361.html [1] http://www.mail-archive.com/linux-media@xxxxxxxxxxxxxxx/msg36206.html [2] http://hverkuil.home.xs4all.nl/spec/media.html#subdev [3] http://www.mail-archive.com/linux-media@xxxxxxxxxxxxxxx/msg36203.html [4] http://www.spinics.net/lists/linux-media/msg39888.html -- Sakari Ailus e-mail: sakari.ailus@xxxxxx jabber/XMPP/Gmail: sailus@xxxxxxxxxxxxxx -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
