From fefa084bde0850447ca5ed84775c094fcf0b2351 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Fri, 8 Jun 2012 20:38:34 +0200 Subject: [PATCH] v4l2object: Don't probe UVC devices for being interlaced UVC devices are never interlaced, and doing VIDIOC_TRY_FMT on them causes expensive and slow USB IO, so don't probe them for interlaced. This shaves 2 seconds of the startup time of cheese with a Logitech Webcam Pro 9000. Signed-off-by: Hans de Goede --- sys/v4l2/gstv4l2object.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/sys/v4l2/gstv4l2object.c b/sys/v4l2/gstv4l2object.c index 6564b91..ce52547 100644 --- a/sys/v4l2/gstv4l2object.c +++ b/sys/v4l2/gstv4l2object.c @@ -1561,10 +1561,18 @@ gst_v4l2_object_probe_caps_for_format_and_size (GstV4l2Object * v4l2object, gint int_width = width; gint int_height = height; - /* interlaced detection using VIDIOC_TRY/S_FMT */ - if (!gst_v4l2_object_get_nearest_size (v4l2object, pixelformat, - &int_width, &int_height, &interlaced)) - return NULL; + if (!strcmp((char *)v4l2object->vcap.driver, "uvcvideo")) { + /* + * UVC devices are never interlaced, and doing VIDIOC_TRY_FMT on them + * causes expensive and slow USB IO, so don't probe them for interlaced + */ + interlaced = FALSE; + } else { + /* Interlaced detection using VIDIOC_TRY/S_FMT */ + if (!gst_v4l2_object_get_nearest_size (v4l2object, pixelformat, + &int_width, &int_height, &interlaced)) + return NULL; + } memset (&ival, 0, sizeof (struct v4l2_frmivalenum)); ival.index = 0; -- 1.7.10.2