Miscellany

/*GST_PLUGIN_PATH=. GST_REGISTRY=./registry.xml GST_DEBUG=*:5 \                gst-launch-0.10 videotestsrc ! ffmpegcolorspace  name=precsp ! \                                cvbgsubtraction ! \                                ffmpegcolorspace name=postcsp ! ximagesink \                2>debug.logERROR: from element /pipeline0/videotestsrc0: Internal data flow error.Additional debug info:gstbasesrc.c(1614): gst_base_src_loop (): /pipeline0/videotestsrc0:streaming task paused, reason not-negotiated (-4)*//* ex:set ts=2 et: */#ifndef __GST_BGSUBTRACTION_H__#define __GST_BGSUBTRACTION_H__#include <glib-object.h>#include <gst/gst.h>#include <gst/base/gstbasetransform.h>#include <cv.h>#include <cvaux.h>G_BEGIN_DECLS#define GST_TYPE_BGSUBTRACTION             (gst_bgsubtraction_get_type())#define GST_BGSUBTRACTION(obj)             (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BGSUBTRACTION,GstBgSubtraction))#define GST_BGSUBTRACTION_CLASS(klass)     (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_BGSUBTRACTION,GstBgSubtractionClass))#define GST_IS_BGSUBTRACTION(obj)          (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BGSUBTRACTION))#define GST_IS_BGSUBTRACTION_CLASS(klass)  (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_BGSUBTRACTION))#define GST_TYPE_BGSUBTRACTION_OP          (gst_bgsubtraction_op_get_type())typedef struct _GstBgSubtraction      GstBgSubtraction;typedef struct _GstBgSubtractionClass GstBgSubtractionClass;struct _GstBgSubtraction{  GstBaseTransform parent;  /*< private >*/  CvBGStatModel *model;  IplImage *srcimage;  IplImage *dstimage; /* gray levels */  CvSize size;  int channels;  int step;};struct _GstBgSubtractionClass {  GstBaseTransformClass parent_class;};GType gst_bgsubtraction_get_type (void);G_END_DECLS#endif /* __GST_BGSUBTRACTION_H__ *//* ex:set ts=2 et: */#include "gstbgsubtraction.h"GST_DEBUG_CATEGORY_STATIC (gst_bgsubtraction_debug);#define GST_CAT_DEFAULT gst_bgsubtraction_debugstatic const GstElementDetails bgsubtraction_details =   GST_ELEMENT_DETAILS (    "Background subtraction",    "Filter/Vision",    "Extracts the background from a video sequence",    "Steve Frécinaux <code@istique.net>"  );static GstStaticPadTemplate sink_factory =  GST_STATIC_PAD_TEMPLATE (    "sink",    GST_PAD_SINK,    GST_PAD_ALWAYS,    GST_STATIC_CAPS ("video/x-raw-gray")//    GST_STATIC_CAPS ("video/x-raw-gray ; video/x-raw-rgb ; video/x-raw-yuv")  );static GstStaticPadTemplate src_factory =  GST_STATIC_PAD_TEMPLATE (    "src",    GST_PAD_SRC,    GST_PAD_ALWAYS,    GST_STATIC_CAPS ("video/x-raw-gray")  );enum{  PROP_0};GST_BOILERPLATE (GstBgSubtraction, gst_bgsubtraction, GstBaseTransform,                 GST_TYPE_BASE_TRANSFORM);static voidgst_bgsubtraction_set_property (GObject *object, guint prop_id,                                const GValue *value, GParamSpec *pspec){  GstBgSubtraction *filter = GST_BGSUBTRACTION (object);  switch (prop_id) {    default:      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);      break;  }}static voidgst_bgsubtraction_get_property (GObject *object, guint prop_id,                                GValue *value, GParamSpec *pspec){  GstBgSubtraction *filter = GST_BGSUBTRACTION (object);  switch (prop_id) {    default:      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);      break;  }}static GstCaps *gst_bgsubtraction_transform_caps (GstBaseTransform *base,                                   GstPadDirection direction, GstCaps *caps){  GstBgSubtraction *filter = GST_BGSUBTRACTION (base);  GstCaps *tcaps;  GstStructure *structure;  int i, n;  const GValue *width, *height, *framerate, *par;  /* informations that should be conserved */  structure = gst_caps_get_structure (caps, 0);  width = gst_structure_get_value (structure, "width");  height = gst_structure_get_value (structure, "height");  framerate = gst_structure_get_value (structure, "framerate");  par = gst_structure_get_value (structure, "pixel-aspect-ratio");  if (direction == GST_PAD_SINK) {    tcaps = gst_static_pad_template_get_caps (&src_factory);  } else if (direction == GST_PAD_SRC) {    tcaps = gst_static_pad_template_get_caps (&sink_factory);  } else {    g_return_val_if_reached (NULL);  }  tcaps = gst_caps_make_writable (tcaps);  n = gst_caps_get_size (tcaps);  for (i = 0; i < n; i++) {    structure = gst_caps_get_structure (tcaps, i);    if (width != NULL)      gst_structure_set_value (structure, "width", width);    if (height != NULL)      gst_structure_set_value (structure, "height", height);    if (framerate != NULL)      gst_structure_set_value (structure, "framerate", framerate);    if (par != NULL)      gst_structure_set_value (structure, "pixel-aspect-ratio", par);  }//  gst_caps_do_simplify (tcaps);  return tcaps;}static gbooleangst_bgsubtraction_get_unit_size (GstBaseTransform *base, GstCaps *caps,                                 guint *size){  GstBgSubtraction *filter = GST_BGSUBTRACTION (base);  GstStructure *structure;  gint width, height, bpp = 8;  structure = gst_caps_get_structure (caps, 0);  if (gst_structure_get_int (structure, "width", &width) &&      gst_structure_get_int (structure, "height", &height)) {    *size = width * height; /* because the output image is gray-level */    return TRUE;  }    return FALSE;}static gbooleangst_bgsubtraction_set_caps (GstBaseTransform *base, GstCaps *incaps,                             GstCaps *outcaps){  GstBgSubtraction *filter = GST_BGSUBTRACTION (base);  GstStructure *structure;  int bpp = 8;  gboolean ret;  structure = gst_caps_get_structure (incaps, 0);  /* Update the image header so it can contain the new image */  gst_structure_get_int (structure, "width", &(filter->size.width));  gst_structure_get_int (structure, "height", &(filter->size.height));  gst_structure_get_int (structure, "bpp", &bpp);  filter->channels = bpp / 8;  filter->step = filter->channels * filter->size.width;  if (filter->srcimage != NULL)    cvReleaseImageHeader (&(filter->srcimage));  filter->srcimage = cvCreateImageHeader (filter->size, IPL_DEPTH_8U, filter->channels);  if (filter->dstimage != NULL)    cvReleaseImageHeader (&(filter->dstimage));  filter->dstimage = cvCreateImageHeader (filter->size, IPL_DEPTH_8U, 1);  if (filter->model != NULL) {    cvReleaseBGStatModel (&(filter->model));    filter->model = NULL;  }  return TRUE;}static GstFlowReturngst_bgsubtraction_transform (GstBaseTransform *base, GstBuffer *inbuf,                             GstBuffer *outbuf){  GstBgSubtraction *filter = GST_BGSUBTRACTION (base);  gst_buffer_stamp (outbuf, inbuf);  cvSetData (filter->srcimage, GST_BUFFER_DATA (inbuf), filter->step);  cvSetData (filter->dstimage, GST_BUFFER_DATA (outbuf), filter->size.width);  if (filter->model == NULL) {    /* initialize the model with the first frame (ie the current one) */    filter->model = cvCreateGaussianBGModel (filter->srcimage, NULL);  } else {    /* update the current model */    cvUpdateBGStatModel (filter->srcimage, filter->model);  }  cvCopy (filter->model->foreground, filter->dstimage, NULL);  return GST_FLOW_OK;}static voidgst_bgsubtraction_init (GstBgSubtraction *filter, GstBgSubtractionClass *klass){  filter->model = NULL;    filter->step = 0;  filter->srcimage = NULL;  filter->dstimage = NULL;}static voidgst_bgsubtraction_finalize (GObject *object){  GstBgSubtraction *filter = GST_BGSUBTRACTION (object);  if (filter->srcimage != NULL)    cvReleaseImageHeader (&(filter->srcimage));    if (filter->dstimage != NULL)    cvReleaseImageHeader (&(filter->dstimage));  if (filter->model != NULL)    cvReleaseBGStatModel (&(filter->model));  G_OBJECT_CLASS (parent_class)->finalize (object);}static voidgst_bgsubtraction_base_init (gpointer klass){  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);  gst_element_class_add_pad_template (element_class,                                      gst_static_pad_template_get (&src_factory));  gst_element_class_add_pad_template (element_class,                                      gst_static_pad_template_get (&sink_factory));  gst_element_class_set_details (element_class, &bgsubtraction_details);}static voidgst_bgsubtraction_class_init (GstBgSubtractionClass *klass){  GObjectClass *object_class = G_OBJECT_CLASS (klass);  GstElementClass *element_class = GST_ELEMENT_CLASS (klass);  GstBaseTransformClass *transform_class = GST_BASE_TRANSFORM_CLASS (klass);  object_class->set_property = gst_bgsubtraction_set_property;  object_class->get_property = gst_bgsubtraction_get_property;  object_class->finalize = gst_bgsubtraction_finalize;#if 1  transform_class->transform_caps = GST_DEBUG_FUNCPTR (gst_bgsubtraction_transform_caps);#endif  transform_class->get_unit_size = GST_DEBUG_FUNCPTR (gst_bgsubtraction_get_unit_size);  transform_class->set_caps = GST_DEBUG_FUNCPTR (gst_bgsubtraction_set_caps);  transform_class->transform = GST_DEBUG_FUNCPTR (gst_bgsubtraction_transform);  GST_DEBUG_CATEGORY_INIT (gst_bgsubtraction_debug, "bgsubtraction",                           0, "Background Subtraction");}