On Fri, 26 Jun 2009, jmdk wrote: > Hello, > > I have a Hauppauge HVR-1900 which works fine with the pvrusb2 driver. > However because most TV channels now air with 16:9 content inside 4:3 > images, I would like to crop out the top and bottom black bars before > encoding via the hardware MPEG2 encoder. I tried using the ctl_crop_top > and ctl_crop_height in /sysfs as well as the --set-crop option of > v4l2-ctrl but only received error messages indicating a value out of range. > > The card has a cx25843 which should support cropping. Does anyone know > how to get this feature to work ? > > Thanks in advance for the help, Unfortunately the cx25840 driver does not implement any cropping capability and the recent change to the v4l-subdevice architecture currently lacks the API entrypoints to make such a thing possible :-( A pvrusb2 user a while back (it's in the pvrusb2 list archives) came up with some patches to the cx25840 driver that implement cropping. He also generated corresponding patches for the pvrusb2 driver. I merged his pvrusb2 patches (which is why you see that support in the driver) but not the cx25840 patches since I'm not an expert on that chip and I don't have the ability to verify that the patches preserve correct behavior for all the other devices that use the same chip. I did pass the cx25840 patches to Hans Verkuil and he tried them out at the time and basically pronounced them "ok" but I think even he wasn't sure if it was doing everything right. That was a while ago and the cx25840 driver has undergone enough other changes to make merging those patches a lot more difficult - plus the v4l-subdevice stuff needs additional changes to support the extra cropping API. -Mike -- Mike Isely isely @ isely (dot) net PGP: 03 54 43 4D 75 E5 CC 92 71 16 01 E2 B5 F5 C1 E8 -- 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
