| /* 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; |
| } |