From e605a94e4093e1304b153ab1baf3e5ccef7562e8 Mon Sep 17 00:00:00 2001 From: "William M. Brack" Date: Tue, 25 Mar 2008 12:33:09 +0000 Subject: [PATCH] sys/v4l2/v4l2src_calls.c: Check whether the device supports setting the framerate before trying to set it and then po... Original commit message from CVS: Based on patch by: William M. Brack * sys/v4l2/v4l2src_calls.c: (fractions_are_equal), (gst_v4l2src_set_capture): Check whether the device supports setting the framerate before trying to set it and then posting a warning or error if it doesn't work (#516649, #520092). Also compare fractions more correctly. --- ChangeLog | 10 +++++++ sys/v4l2/v4l2src_calls.c | 77 +++++++++++++++++++++++++++++++----------------- 2 files changed, 60 insertions(+), 27 deletions(-) diff --git a/ChangeLog b/ChangeLog index 8e5fea5..4a95cb1 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,13 @@ +2008-03-25 Tim-Philipp Müller + + Based on patch by: William M. Brack + + * sys/v4l2/v4l2src_calls.c: (fractions_are_equal), + (gst_v4l2src_set_capture): + Check whether the device supports setting the framerate before + trying to set it and then posting a warning or error if it doesn't + work (#516649, #520092). Also compare fractions more correctly. + 2008-03-23 Tim-Philipp Müller * gst/goom/Makefile.am: diff --git a/sys/v4l2/v4l2src_calls.c b/sys/v4l2/v4l2src_calls.c index 9e6a95c..b00d97d 100644 --- a/sys/v4l2/v4l2src_calls.c +++ b/sys/v4l2/v4l2src_calls.c @@ -1111,6 +1111,19 @@ qbuf_failed: */ } +static gboolean +fractions_are_equal (gint num1, gint den1, gint num2, gint den2) +{ + GValue fraction1 = { 0, }, fraction2 = { + 0,}; + + g_value_init (&fraction1, GST_TYPE_FRACTION); + g_value_init (&fraction2, GST_TYPE_FRACTION); + gst_value_set_fraction (&fraction1, num1, den1); + gst_value_set_fraction (&fraction2, num2, den2); + /* we know we don't have to unset the values in this case */ + return (gst_value_compare (&fraction1, &fraction2) == GST_VALUE_EQUAL); +} /****************************************************** * gst_v4l2src_set_capture(): @@ -1153,32 +1166,52 @@ gst_v4l2src_set_capture (GstV4l2Src * v4l2src, guint32 pixelformat, if (format.fmt.pix.pixelformat != pixelformat) goto invalid_pixelformat; + /* Is there a reason we require the caller to always specify a framerate? */ + GST_LOG_OBJECT (v4l2src, "Desired framerate: %u/%u", fps_n, fps_d); + memset (&stream, 0x00, sizeof (struct v4l2_streamparm)); stream.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; if (ioctl (fd, VIDIOC_G_PARM, &stream) < 0) { GST_ELEMENT_WARNING (v4l2src, RESOURCE, SETTINGS, (_("Could not get parameters on device '%s'"), v4l2src->v4l2object->videodev), GST_ERROR_SYSTEM); - } else { /* seems no point in SET, if can't get GET */ - /* Note: V4L2 gives us the frame interval, we need the frame rate */ - stream.parm.capture.timeperframe.numerator = fps_d; - stream.parm.capture.timeperframe.denominator = fps_n; - - if (ioctl (fd, VIDIOC_S_PARM, &stream) < 0) { - GST_ELEMENT_WARNING (v4l2src, RESOURCE, SETTINGS, - (_("Could not set parameters on device '%s'"), - v4l2src->v4l2object->videodev), GST_ERROR_SYSTEM); - - /* FIXME: better test for fraction equality */ - if (stream.parm.capture.timeperframe.numerator != fps_d - || stream.parm.capture.timeperframe.denominator != fps_n) - goto invalid_framerate; - } + goto done; + } + + /* Note: V4L2 provides the frame interval, we have the frame rate */ + if (fractions_are_equal (stream.parm.capture.timeperframe.numerator, + stream.parm.capture.timeperframe.denominator, fps_d, fps_n)) { + GST_LOG_OBJECT (v4l2src, "Desired framerate already set, nothing to do"); + goto done; + } + + /* We want to change the frame rate, so check whether we can. Some cheap USB + * cameras don't have the capability */ + if ((stream.parm.capture.capability & V4L2_CAP_TIMEPERFRAME) == 0) { + GST_DEBUG_OBJECT (v4l2src, "Not setting framerate (not supported)"); + goto done; + } + + GST_LOG_OBJECT (v4l2src, "Setting framerate to %u/%u", fps_n, fps_d); + + /* Note: V4L2 wants the frame interval, we have the frame rate */ + stream.parm.capture.timeperframe.numerator = fps_d; + stream.parm.capture.timeperframe.denominator = fps_n; - v4l2src->fps_d = fps_d; - v4l2src->fps_n = fps_n; + /* some cheap USB cam's won't accept any change */ + if (ioctl (fd, VIDIOC_S_PARM, &stream) < 0) { + GST_ELEMENT_WARNING (v4l2src, RESOURCE, SETTINGS, + (_("Video input device did not accept new frame rate setting.")), + GST_ERROR_SYSTEM); + goto done; } + v4l2src->fps_n = fps_n; + v4l2src->fps_d = fps_d; + GST_INFO_OBJECT (v4l2src, "Set framerate to %u/%u", fps_n, fps_d); + +done: + return TRUE; /* ERRORS */ @@ -1219,16 +1252,6 @@ invalid_pixelformat: GST_FOURCC_ARGS (format.fmt.pix.pixelformat))); return FALSE; } -invalid_framerate: - { - GST_ELEMENT_ERROR (v4l2src, RESOURCE, SETTINGS, - (_("Device '%s' cannot capture at %d/%d frames per second"), - v4l2src->v4l2object->videodev, fps_n, fps_d), - ("Tried to capture at %d/%d fps, but device returned %d/%d fps", - fps_n, fps_d, stream.parm.capture.timeperframe.denominator, - stream.parm.capture.timeperframe.numerator)); - return FALSE; - } } /****************************************************** -- 2.7.4