gstreamer/gst/camerabin/camerabinimage.c

/*
 * GStreamer
 * Copyright (C) 2008 Nokia Corporation <multimedia@maemo.org>
 *
 * 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/**
 * SECTION:camerabinimage
 * @short_description: image capturing module of #GstCameraBin
 *
 * <refsect2>
 * <para>
 *
 * The pipeline for this module is:
 *
 * <informalexample>
 * <programlisting>
 *-----------------------------------------------------------------------------
 *
 * -> [post proc] -> csp -> imageenc -> metadatamuxer -> filesink
 *
 *-----------------------------------------------------------------------------
 * </programlisting>
 * </informalexample>
 *
 * The image bin opens file for image writing in READY to PAUSED state change.
 * The image bin closes the file in PAUSED to READY state change.
 *
 * </para>
 * </refsect2>
 */

/*
 * includes
 */

#include <gst/gst.h>

#include "camerabinimage.h"
#include "camerabindebug.h"
#include "camerabingeneral.h"
#include "gstcamerabin-enum.h"

#include "string.h"

/* default internal element names */

#define DEFAULT_SINK "filesink"
#define DEFAULT_ENC "jpegenc"
#define DEFAULT_META_MUX "jifmux"
#define DEFAULT_FLAGS GST_CAMERABIN_FLAG_IMAGE_COLOR_CONVERSION

enum
{
  PROP_0,
  PROP_FILENAME
};

static gboolean gst_camerabin_image_create_elements (GstCameraBinImage * img);
static void gst_camerabin_image_destroy_elements (GstCameraBinImage * img);

static void gst_camerabin_image_dispose (GstCameraBinImage * sink);
static GstStateChangeReturn
gst_camerabin_image_change_state (GstElement * element,
    GstStateChange transition);
static gboolean gst_camerabin_image_send_event (GstElement * element,
    GstEvent * event);
static void gst_camerabin_image_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void gst_camerabin_image_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);
static gboolean metadata_write_probe (GstPad * pad, GstBuffer * buffer,
    gpointer u_data);
static gboolean prepare_element (GList ** result,
    const gchar * default_element_name, GstElement * app_elem,
    GstElement ** res_elem);


GST_BOILERPLATE (GstCameraBinImage, gst_camerabin_image, GstBin, GST_TYPE_BIN);

static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS_ANY);

static void
gst_camerabin_image_base_init (gpointer klass)
{
  GstElementClass *eklass = GST_ELEMENT_CLASS (klass);

  gst_element_class_add_pad_template (eklass,
      gst_static_pad_template_get (&sink_template));
  gst_element_class_set_details_simple (eklass,
      "Image capture bin for camerabin", "Bin/Image",
      "Process and store image data",
      "Edgard Lima <edgard.lima@indt.org.br>, "
      "Nokia Corporation <multimedia@maemo.org>");
}

static void
gst_camerabin_image_class_init (GstCameraBinImageClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *eklass = GST_ELEMENT_CLASS (klass);

  gobject_class = G_OBJECT_CLASS (klass);
  gobject_class->dispose =
      (GObjectFinalizeFunc) GST_DEBUG_FUNCPTR (gst_camerabin_image_dispose);
  eklass->change_state = GST_DEBUG_FUNCPTR (gst_camerabin_image_change_state);
  eklass->send_event = GST_DEBUG_FUNCPTR (gst_camerabin_image_send_event);

  gobject_class->set_property =
      GST_DEBUG_FUNCPTR (gst_camerabin_image_set_property);
  gobject_class->get_property =
      GST_DEBUG_FUNCPTR (gst_camerabin_image_get_property);

  /**
   * GstCameraBinImage:filename
   *
   * This property can be used to specify the filename of the image.
   *
   **/
  g_object_class_install_property (gobject_class, PROP_FILENAME,
      g_param_spec_string ("filename", "Filename",
          "Filename of the image to save", NULL,
          G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
}

static void
gst_camerabin_image_init (GstCameraBinImage * img,
    GstCameraBinImageClass * g_class)
{
  img->filename = g_string_new ("");

  img->post = NULL;
  img->csp = NULL;
  img->enc = NULL;
  img->app_enc = NULL;
  img->meta_mux = NULL;
  img->sink = NULL;

  /* Create src and sink ghost pads */
  img->sinkpad = gst_ghost_pad_new_no_target ("sink", GST_PAD_SINK);
  gst_element_add_pad (GST_ELEMENT (img), img->sinkpad);

  img->flags = DEFAULT_FLAGS;
}

static void
gst_camerabin_image_dispose (GstCameraBinImage * img)
{
  GST_DEBUG_OBJECT (img, "disposing");

  g_string_free (img->filename, TRUE);
  img->filename = NULL;

  if (img->elements) {
    g_list_free (img->elements);
    img->elements = NULL;
  }

  if (img->sink) {
    GST_LOG_OBJECT (img, "disposing %s with refcount %d",
        GST_ELEMENT_NAME (img->sink), GST_OBJECT_REFCOUNT_VALUE (img->sink));
    gst_object_unref (img->sink);
    img->sink = NULL;
  }

  if (img->meta_mux) {
    GST_LOG_OBJECT (img, "disposing %s with refcount %d",
        GST_ELEMENT_NAME (img->meta_mux),
        GST_OBJECT_REFCOUNT_VALUE (img->meta_mux));
    gst_object_unref (img->meta_mux);
    img->meta_mux = NULL;
  }

  if (img->enc) {
    GST_LOG_OBJECT (img, "disposing %s with refcount %d",
        GST_ELEMENT_NAME (img->enc), GST_OBJECT_REFCOUNT_VALUE (img->enc));
    gst_object_unref (img->enc);
    img->enc = NULL;
  }


  /* Note: if imagebin was never set to READY state the
     ownership of elements created by application were never
     taken by bin and therefore gst_object_sink is called for
     these elements (they may still be in floating state
     and not unreffed properly without sinking first)
     FIXME, something else is wrong if you have to sink here
   */
  if (img->app_enc) {
    //gst_object_ref_sink (img->app_enc);
    GST_LOG_OBJECT (img, "disposing %s with refcount %d",
        GST_ELEMENT_NAME (img->app_enc),
        GST_OBJECT_REFCOUNT_VALUE (img->app_enc));
    gst_object_unref (img->app_enc);
    img->app_enc = NULL;
  }

  if (img->post) {
    //gst_object_ref_sink (img->post);
    GST_LOG_OBJECT (img, "disposing %s with refcount %d",
        GST_ELEMENT_NAME (img->post), GST_OBJECT_REFCOUNT_VALUE (img->post));
    gst_object_unref (img->post);
    img->post = NULL;
  }

  G_OBJECT_CLASS (parent_class)->dispose ((GObject *) img);
}

static GstStateChangeReturn
gst_camerabin_image_change_state (GstElement * element,
    GstStateChange transition)
{
  GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
  GstCameraBinImage *img = GST_CAMERABIN_IMAGE (element);

  GST_DEBUG_OBJECT (element, "changing state: %s -> %s",
      gst_element_state_get_name (GST_STATE_TRANSITION_CURRENT (transition)),
      gst_element_state_get_name (GST_STATE_TRANSITION_NEXT (transition)));

  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      if (!gst_camerabin_image_create_elements (img)) {
        return GST_STATE_CHANGE_FAILURE;
      }
      /* Allow setting filename when image bin in READY state */
      gst_element_set_locked_state (img->sink, TRUE);
      GST_INFO_OBJECT (img, "locking imagebin->sink state to %s",
          gst_element_state_get_name (GST_STATE (img->sink)));
      break;
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      if (!g_str_equal (img->filename->str, "")) {
        GST_INFO_OBJECT (img, "preparing image with filename: %s",
            img->filename->str);
        gst_element_set_locked_state (img->sink, FALSE);
      } else {
        GST_INFO_OBJECT (img, "keep sink locked, we have no filename yet");
      }
      break;
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      /* Set sink to NULL in order to write the file _now_ */
      GST_INFO_OBJECT (img, "write image with filename: %s",
          img->filename->str);
      gst_element_set_locked_state (img->sink, TRUE);
      gst_element_set_state (img->sink, GST_STATE_NULL);
      g_string_assign (img->filename, "");
      break;
    default:
      break;
  }

  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);

  switch (transition) {
    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
      /* Write debug graph to file */
      GST_DEBUG_BIN_TO_DOT_FILE_WITH_TS (GST_BIN (GST_ELEMENT_PARENT (img)),
          GST_DEBUG_GRAPH_SHOW_MEDIA_TYPE |
          GST_DEBUG_GRAPH_SHOW_NON_DEFAULT_PARAMS, "imagebin.playing");
      break;
    case GST_STATE_CHANGE_READY_TO_NULL:
      gst_camerabin_image_destroy_elements (img);
      break;
    default:
      break;
  }

  GST_DEBUG_OBJECT (element, "changed state: %s -> %s = %s",
      gst_element_state_get_name (GST_STATE_TRANSITION_CURRENT (transition)),
      gst_element_state_get_name (GST_STATE_TRANSITION_NEXT (transition)),
      gst_element_state_change_return_get_name (ret));

  return ret;
}

gboolean
gst_camerabin_image_send_event (GstElement * element, GstEvent * event)
{
  GstCameraBinImage *bin = GST_CAMERABIN_IMAGE (element);
  gboolean ret = FALSE;

  GST_INFO ("got %s event", GST_EVENT_TYPE_NAME (event));

  if (GST_EVENT_IS_DOWNSTREAM (event)) {
    ret = gst_pad_send_event (bin->sinkpad, event);
  } else {
    if (bin->sink) {
      ret = gst_element_send_event (bin->sink, event);
    } else {
      GST_WARNING ("upstream event handling failed");
    }
  }

  return ret;
}

static void
gst_camerabin_image_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec)
{
  GstCameraBinImage *bin = GST_CAMERABIN_IMAGE (object);

  switch (prop_id) {
    case PROP_FILENAME:
      g_string_assign (bin->filename, g_value_get_string (value));
      GST_INFO_OBJECT (bin, "received filename: '%s'", bin->filename->str);
      if (bin->sink) {
        if (!g_str_equal (bin->filename->str, "")) {
          g_object_set (G_OBJECT (bin->sink), "location", bin->filename->str,
              NULL);
          gst_element_set_locked_state (bin->sink, FALSE);
          gst_element_sync_state_with_parent (bin->sink);
        } else {
          GST_INFO_OBJECT (bin, "empty filename");
        }
      } else {
        GST_INFO_OBJECT (bin, "no sink, not setting name yet");
      }
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

static void
gst_camerabin_image_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec)
{
  GstCameraBinImage *bin = GST_CAMERABIN_IMAGE (object);

  switch (prop_id) {
    case PROP_FILENAME:
      g_value_set_string (value, bin->filename->str);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

/*
 * gst_camerabin_image_prepare_elements:
 * @imagebin: a pointer to #GstCameraBinImage object
 *
 * This function creates an ordered list of elements configured for imagebin
 * pipeline and creates the elements if necessary. It also stores pointers
 * to created elements for re-using them.
 *
 * Image bin:
 *  img->sinkpad ! [ post process !] [ csp !] encoder ! metadata ! filesink
 *
 * Returns: %FALSE if there was error creating element, %TRUE otherwise
 */
gboolean
gst_camerabin_image_prepare_elements (GstCameraBinImage * imagebin)
{
  gboolean ret = FALSE;
  GstPad *sinkpad = NULL;

  g_return_val_if_fail (imagebin != NULL, FALSE);

  GST_DEBUG_OBJECT (imagebin, "preparing image capture elements");

  if (imagebin->elements != NULL) {
    g_list_free (imagebin->elements);
    imagebin->elements = NULL;
  }

  /* Create file sink element */
  if (!prepare_element (&imagebin->elements, DEFAULT_SINK, NULL,
          &imagebin->sink)) {
    goto done;
  } else {
    g_object_set (G_OBJECT (imagebin->sink), "location",
        imagebin->filename->str, "async", FALSE, "buffer-mode", 2,
        /* non buffered io */ NULL);
  }

  /* Create metadata muxer element */
  if (!prepare_element (&imagebin->elements, DEFAULT_META_MUX, NULL,
          &imagebin->meta_mux)) {
    goto done;
  } else if (!imagebin->metadata_probe_id) {
    /* Add probe for default XMP metadata writing */
    sinkpad = gst_element_get_static_pad (imagebin->meta_mux, "sink");
    imagebin->metadata_probe_id =
        gst_pad_add_buffer_probe (sinkpad, G_CALLBACK (metadata_write_probe),
        imagebin);
    gst_object_unref (sinkpad);
  }

  /* Create image encoder element */
  if (!prepare_element (&imagebin->elements, DEFAULT_ENC, imagebin->app_enc,
          &imagebin->enc)) {
    goto done;
  }

  /* Create optional colorspace conversion element */
  if (imagebin->flags & GST_CAMERABIN_FLAG_IMAGE_COLOR_CONVERSION) {
    if (!prepare_element (&imagebin->elements, "ffmpegcolorspace", NULL,
            &imagebin->csp)) {
      goto done;
    }
  }

  /* Add optional image post processing element */
  if (!prepare_element (&imagebin->elements, NULL, imagebin->post,
          &imagebin->post)) {
    goto done;
  }

  ret = TRUE;

done:
  GST_DEBUG_OBJECT (imagebin, "preparing finished %s", ret ? "OK" : "NOK");
  return ret;
}


/*
 * static helper functions implementation
 */

/*
 * metadata_write_probe:
 * @pad: sink pad of metadata muxer
 * @buffer: received buffer
 * @u_data: image bin object
 *
 * Buffer probe that sets Xmp.dc.type and Xmp.dc.format tags
 * to metadata muxer based on preceding element src pad caps.
 *
 * Returns: TRUE always
 */
static gboolean
metadata_write_probe (GstPad * pad, GstBuffer * buffer, gpointer u_data)
{
  /* Add XMP tags */
  GstCameraBinImage *img = NULL;
  GstTagSetter *setter = NULL;
  GstPad *srcpad = NULL;
  GstCaps *caps = NULL;
  GstStructure *st = NULL;

  img = GST_CAMERABIN_IMAGE (u_data);

  g_return_val_if_fail (img != NULL, TRUE);

  setter = GST_TAG_SETTER (img->meta_mux);

  if (!setter) {
    GST_WARNING_OBJECT (img, "setting tags failed");
    goto done;
  }

  /* Xmp.dc.type tag */
  gst_tag_setter_add_tags (setter, GST_TAG_MERGE_REPLACE,
      GST_TAG_CODEC, "Image", NULL);
  /* Xmp.dc.format tag */
  if (img->enc) {
    srcpad = gst_element_get_static_pad (img->enc, "src");
  }
  GST_LOG_OBJECT (img, "srcpad:%" GST_PTR_FORMAT, srcpad);
  if (srcpad) {
    caps = gst_pad_get_negotiated_caps (srcpad);
    GST_LOG_OBJECT (img, "caps:%" GST_PTR_FORMAT, caps);
    if (caps) {
      /* If there are many structures, we can't know which one to use */
      if (gst_caps_get_size (caps) != 1) {
        GST_WARNING_OBJECT (img, "can't decide structure for format tag");
        goto done;
      }
      st = gst_caps_get_structure (caps, 0);
      if (st) {
        GST_DEBUG_OBJECT (img, "Xmp.dc.format:%s", gst_structure_get_name (st));
        gst_tag_setter_add_tags (setter, GST_TAG_MERGE_REPLACE,
            GST_TAG_VIDEO_CODEC, gst_structure_get_name (st), NULL);
      }
    }
  }
done:
  if (caps)
    gst_caps_unref (caps);
  if (srcpad)
    gst_object_unref (srcpad);

  return TRUE;
}

/*
 * prepare_element:
 * @result: result list address
 * @default_element_name: name of default element to be created
 * @app_elem: pointer to application set element
 * @res_elem: pointer to current element to be replaced if needed
 *
 * This function chooses given image capture element or creates a new one and
 * and prepends it to @result list.
 *
 * Returns: %FALSE if there was error creating new element, %TRUE otherwise
 */
static gboolean
prepare_element (GList ** result, const gchar * default_element_name,
    GstElement * app_elem, GstElement ** res_elem)
{
  GstElement *elem = NULL;
  gboolean ret = TRUE;

  if (app_elem) {
    /* Prefer application set element */
    elem = app_elem;
  } else if (*res_elem) {
    /* Use existing element if any */
    elem = *res_elem;
  } else if (default_element_name) {
    /* Create new element */
    if (!(elem = gst_element_factory_make (default_element_name, NULL))) {
      GST_WARNING ("creating %s failed", default_element_name);
      ret = FALSE;
    }
  }

  if (*res_elem != elem) {
    /* Keep reference and store pointer to chosen element, which can be re-used
       until imagebin is disposed or new image capture element is chosen. */
    gst_object_replace ((GstObject **) res_elem, (GstObject *) elem);
  }
  if (elem) {
    *result = g_list_prepend (*result, elem);
  }

  return ret;
}

/*
 * gst_camerabin_image_link_first_element:
 * @img: a pointer to #GstCameraBinImage object
 * @elem: first element to be linked on imagebin
 *
 * Adds given element to imagebin and links it to imagebin's ghost sink pad.
 *
 * Returns: %TRUE if adding and linking succeeded, %FALSE otherwise
 */
static gboolean
gst_camerabin_image_link_first_element (GstCameraBinImage * imagebin,
    GstElement * elem)
{
  GstPad *first_sinkpad = NULL;
  gboolean ret = FALSE;

  g_return_val_if_fail (imagebin != NULL, FALSE);
  /* Link given element to imagebin ghost sink pad */
  if (gst_bin_add (GST_BIN (imagebin), elem)) {
    first_sinkpad = gst_element_get_static_pad (elem, "sink");
    if (first_sinkpad) {
      if (gst_ghost_pad_set_target (GST_GHOST_PAD (imagebin->sinkpad),
              first_sinkpad)) {
        ret = TRUE;
      } else {
        GST_WARNING ("linking first element failed");
      }
      gst_object_unref (first_sinkpad);
    } else {
      GST_WARNING ("no sink pad in first element");
    }
  } else {
    GST_WARNING ("adding element failed");
  }
  return ret;
}

/*
 * gst_camerabin_image_link_elements:
 * @imagebin: a pointer to #GstCameraBinImage object
 *
 * Link elements configured to imagebin elements list.
 *
 * Returns %TRUE if linking succeeded, %FALSE otherwise.
 */
static gboolean
gst_camerabin_image_link_elements (GstCameraBinImage * imagebin)
{
  GList *prev = NULL;
  GList *next = NULL;
  gboolean ret = FALSE;

  GST_DEBUG_OBJECT (imagebin, "linking image elements");

  if (!imagebin->elements) {
    GST_WARNING ("no elements to link");
    goto done;
  }

  /* Link the elements in list */
  prev = imagebin->elements;
  next = g_list_next (imagebin->elements);
  for (; next != NULL; next = g_list_next (next)) {
    /* Link first element in list to imagebin ghost sink pad */
    if (prev == imagebin->elements
        && !gst_camerabin_image_link_first_element (imagebin,
            GST_ELEMENT (prev->data))) {
      goto done;
    }
    if (!gst_bin_add (GST_BIN (imagebin), GST_ELEMENT (next->data))) {
      GST_WARNING_OBJECT (imagebin, "adding element failed");
      goto done;
    }
    GST_LOG_OBJECT (imagebin, "linking %s - %s",
        GST_ELEMENT_NAME (GST_ELEMENT (prev->data)),
        GST_ELEMENT_NAME (GST_ELEMENT (next->data)));
    if (!gst_element_link (GST_ELEMENT (prev->data), GST_ELEMENT (next->data))) {
      GST_WARNING_OBJECT (imagebin, "linking element failed");
      goto done;
    }

    prev = next;
  }

  ret = TRUE;

done:

  if (!ret) {
    gst_camerabin_remove_elements_from_bin (GST_BIN (imagebin));
  }

  GST_DEBUG_OBJECT (imagebin, "linking finished %s", ret ? "OK" : "NOK");

  return ret;
}

/*
 * gst_camerabin_image_create_elements:
 * @img: a pointer to #GstCameraBinImage object
 *
 * This function creates needed elements, adds them to
 * imagebin and links them.
 *
 * Returns %TRUE if success, %FALSE otherwise.
 */
static gboolean
gst_camerabin_image_create_elements (GstCameraBinImage * img)
{
  gboolean ret = FALSE;
  g_return_val_if_fail (img != NULL, FALSE);

  if (gst_camerabin_image_prepare_elements (img)) {
    ret = gst_camerabin_image_link_elements (img);
  }

  return ret;
}

/*
 * gst_camerabin_image_destroy_elements:
 * @img: a pointer to #GstCameraBinImage object
 *
 * This function releases resources allocated in
 * gst_camerabin_image_create_elements.
 *
 */
static void
gst_camerabin_image_destroy_elements (GstCameraBinImage * img)
{
  GST_LOG ("destroying image elements");

  gst_ghost_pad_set_target (GST_GHOST_PAD (img->sinkpad), NULL);

  gst_camerabin_remove_elements_from_bin (GST_BIN (img));
}

void
gst_camerabin_image_set_encoder (GstCameraBinImage * img, GstElement * encoder)
{
  GST_DEBUG ("setting image encoder %" GST_PTR_FORMAT, encoder);
  if (img->app_enc)
    gst_object_unref (img->app_enc);
  if (encoder)
    gst_object_ref (encoder);

  img->app_enc = encoder;
}

void
gst_camerabin_image_set_postproc (GstCameraBinImage * img,
    GstElement * postproc)
{
  GST_DEBUG ("setting image postprocessing element %" GST_PTR_FORMAT, postproc);
  if (img->post)
    gst_object_unref (img->post);
  if (postproc)
    gst_object_ref (postproc);

  img->post = postproc;
}

void
gst_camerabin_image_set_flags (GstCameraBinImage * img, GstCameraBinFlags flags)
{
  GST_DEBUG_OBJECT (img, "setting image flags: %d", flags);
  img->flags = flags;
}

GstElement *
gst_camerabin_image_get_encoder (GstCameraBinImage * img)
{
  GstElement *enc;

  if (img->app_enc) {
    enc = img->app_enc;
  } else {
    enc = img->enc;
  }

  return enc;
}

GstElement *
gst_camerabin_image_get_postproc (GstCameraBinImage * img)
{
  return img->post;
}