V4L/DVB: em28xx: reduce cropping for VBI area

It turns up we can reduce the starting line for the active area, which results
in more data being captured when under PAL (while the full VBI capture window
still stays properly encoded).

This work was sponsored by EyeMagnet Limited.

Signed-off-by: Devin Heitmueller <dheitmueller@kernellabs.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Devin Heitmueller 2010-01-22 02:05:24 -03:00 committed by Mauro Carvalho Chehab
parent 33c02facb5
commit 1744feab9a

View File

@ -782,11 +782,15 @@ int em28xx_resolution_set(struct em28xx *dev)
em28xx_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
/* If we don't set the start position to 4 in VBI mode, we end up
with line 21 being YUYV encoded instead of being in 8-bit
greyscale */
/* If we don't set the start position to 2 in VBI mode, we end up
with line 20/21 being YUYV encoded instead of being in 8-bit
greyscale. The core of the issue is that line 21 (and line 23 for
PAL WSS) are inside of active video region, and as a result they
get the pixelformatting associated with that area. So by cropping
it out, we end up with the same format as the rest of the VBI
region */
if (em28xx_vbi_supported(dev) == 1)
em28xx_capture_area_set(dev, 0, 4, width >> 2, height >> 2);
em28xx_capture_area_set(dev, 0, 2, width >> 2, height >> 2);
else
em28xx_capture_area_set(dev, 0, 0, width >> 2, height >> 2);