blob: 0b08100e9f079ef55a064aa035a02406fb0c0c41 [file] [log] [blame]
/* GStreamer
* Copyright (C) 2011 David Schleef <ds@entropywave.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin Street, Suite 500,
* Boston, MA 02110-1335, USA.
*/
/**
* SECTION:element-gstzebrastripe
*
* The zebrastripe element marks areas of images in a video stream
* that are brighter than a threshold with a diagonal zebra stripe
* pattern. Typically, this is used to aid in adjusting the exposure
* setting on the camera. Setting the threshold to 95 or 100 will
* show areas that are completely overexposed and clipping. A
* threshold setting of 70 is often used to properly adjust skin
* tones.
*
* <refsect2>
* <title>Example launch line</title>
* |[
* gst-launch -v videotestsrc ! zebrastripe ! xvimagesink
* ]|
* Marks overexposed areas of the video with zebra stripes.
*
* The threshold property is expressed as percentage of full scale,
* whereas common usage expresses thresholds in terms of IRE. The
* property setting can be calculated from IRE by using the formula
* percent = (IRE * 1.075) - 7.5. Note that 100 IRE corresponds to
* 100 %, and 70 IRE corresponds to 68 %.
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst.h>
#include <gst/video/video.h>
#include <gst/video/gstvideofilter.h>
#include "gstzebrastripe.h"
#include <math.h>
GST_DEBUG_CATEGORY_STATIC (gst_zebra_stripe_debug_category);
#define GST_CAT_DEFAULT gst_zebra_stripe_debug_category
/* prototypes */
static void gst_zebra_stripe_set_property (GObject * object,
guint property_id, const GValue * value, GParamSpec * pspec);
static void gst_zebra_stripe_get_property (GObject * object,
guint property_id, GValue * value, GParamSpec * pspec);
static gboolean gst_zebra_stripe_start (GstBaseTransform * trans);
static gboolean gst_zebra_stripe_stop (GstBaseTransform * trans);
static GstFlowReturn gst_zebra_stripe_transform_frame_ip (GstVideoFilter *
filter, GstVideoFrame * frame);
enum
{
PROP_0,
PROP_THRESHOLD
};
#define DEFAULT_THRESHOLD 90
/* pad templates */
#define VIDEO_CAPS GST_VIDEO_CAPS_MAKE( \
"{ I420, Y444, Y42B, Y41B, YUY2, UYVY, AYUV, NV12, NV21, YV12 }")
/* class initialization */
G_DEFINE_TYPE_WITH_CODE (GstZebraStripe, gst_zebra_stripe,
GST_TYPE_VIDEO_FILTER,
GST_DEBUG_CATEGORY_INIT (gst_zebra_stripe_debug_category, "zebrastripe", 0,
"debug category for zebrastripe element"));
static void
gst_zebra_stripe_class_init (GstZebraStripeClass * klass)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
GstBaseTransformClass *base_transform_class =
GST_BASE_TRANSFORM_CLASS (klass);
GstVideoFilterClass *video_filter_class = GST_VIDEO_FILTER_CLASS (klass);
/* Setting up pads and setting metadata should be moved to
base_class_init if you intend to subclass this class. */
gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
gst_caps_from_string (VIDEO_CAPS)));
gst_element_class_add_pad_template (GST_ELEMENT_CLASS (klass),
gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
gst_caps_from_string (VIDEO_CAPS)));
gst_element_class_set_static_metadata (GST_ELEMENT_CLASS (klass),
"Zebra stripe overlay",
"Filter/Analysis",
"Overlays zebra striping on overexposed areas of video",
"David Schleef <ds@entropywave.com>");
gobject_class->set_property = gst_zebra_stripe_set_property;
gobject_class->get_property = gst_zebra_stripe_get_property;
base_transform_class->start = GST_DEBUG_FUNCPTR (gst_zebra_stripe_start);
base_transform_class->stop = GST_DEBUG_FUNCPTR (gst_zebra_stripe_stop);
video_filter_class->transform_frame_ip =
GST_DEBUG_FUNCPTR (gst_zebra_stripe_transform_frame_ip);
g_object_class_install_property (gobject_class, PROP_THRESHOLD,
g_param_spec_int ("threshold", "Threshold",
"Threshold above which the video is striped", 0, 100,
DEFAULT_THRESHOLD,
G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS));
}
static void
gst_zebra_stripe_init (GstZebraStripe * zebrastripe)
{
}
void
gst_zebra_stripe_set_property (GObject * object, guint property_id,
const GValue * value, GParamSpec * pspec)
{
GstZebraStripe *zebrastripe = GST_ZEBRA_STRIPE (object);
GST_DEBUG_OBJECT (zebrastripe, "set_property");
switch (property_id) {
case PROP_THRESHOLD:
zebrastripe->threshold = g_value_get_int (value);
zebrastripe->y_threshold =
16 + floor (0.5 + 2.19 * zebrastripe->threshold);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
void
gst_zebra_stripe_get_property (GObject * object, guint property_id,
GValue * value, GParamSpec * pspec)
{
GstZebraStripe *zebrastripe = GST_ZEBRA_STRIPE (object);
GST_DEBUG_OBJECT (zebrastripe, "get_property");
switch (property_id) {
case PROP_THRESHOLD:
g_value_set_int (value, zebrastripe->threshold);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
break;
}
}
static gboolean
gst_zebra_stripe_start (GstBaseTransform * trans)
{
#ifndef GST_DISABLE_GST_DEBUG
GstZebraStripe *zebrastripe = GST_ZEBRA_STRIPE (trans);
GST_DEBUG_OBJECT (zebrastripe, "start");
#endif
if (GST_BASE_TRANSFORM_CLASS (gst_zebra_stripe_parent_class)->start)
return
GST_BASE_TRANSFORM_CLASS (gst_zebra_stripe_parent_class)->start (trans);
return TRUE;
}
static gboolean
gst_zebra_stripe_stop (GstBaseTransform * trans)
{
#ifndef GST_DISABLE_GST_DEBUG
GstZebraStripe *zebrastripe = GST_ZEBRA_STRIPE (trans);
GST_DEBUG_OBJECT (zebrastripe, "stop");
#endif
if (GST_BASE_TRANSFORM_CLASS (gst_zebra_stripe_parent_class)->stop)
return
GST_BASE_TRANSFORM_CLASS (gst_zebra_stripe_parent_class)->stop (trans);
return TRUE;
}
static GstFlowReturn
gst_zebra_stripe_transform_frame_ip (GstVideoFilter * filter,
GstVideoFrame * frame)
{
GstZebraStripe *zebrastripe = GST_ZEBRA_STRIPE (filter);
int width = frame->info.width;
int height = frame->info.height;
int i, j;
int threshold = zebrastripe->y_threshold;
int t = zebrastripe->t;
int offset = 0;
int pixel_stride = 0, y_position = 0;
GST_DEBUG_OBJECT (zebrastripe, "transform_frame_ip");
zebrastripe->t++;
pixel_stride = GST_VIDEO_FORMAT_INFO_PSTRIDE (frame->info.finfo, 0);
switch (frame->info.finfo->format) {
case GST_VIDEO_FORMAT_I420:
case GST_VIDEO_FORMAT_Y41B:
case GST_VIDEO_FORMAT_Y444:
case GST_VIDEO_FORMAT_Y42B:
case GST_VIDEO_FORMAT_YUY2:
case GST_VIDEO_FORMAT_NV12:
case GST_VIDEO_FORMAT_NV21:
case GST_VIDEO_FORMAT_YV12:
break;
case GST_VIDEO_FORMAT_UYVY:
offset = 1;
break;
case GST_VIDEO_FORMAT_AYUV:
y_position = 1;
break;
default:
g_assert_not_reached ();
}
for (j = 0; j < height; j++) {
guint8 *data =
(guint8 *) frame->data[0] + frame->info.stride[0] * j + offset;
for (i = 0; i < width; i++) {
if (data[pixel_stride * i + y_position] >= threshold) {
if ((i + j + t) & 0x4)
data[pixel_stride * i + y_position] = 16;
}
}
}
return GST_FLOW_OK;
}