gstreamer/ext/jpeg/gstsmokedec.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 *
 * 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 St, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

/**
 * SECTION:element-smokedec
 * @title: smokedec
 *
 * Decodes images in smoke format.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>

/*#define DEBUG_ENABLED*/
#include "gstsmokedec.h"
#include <gst/video/video.h>

GST_DEBUG_CATEGORY_STATIC (smokedec_debug);
#define GST_CAT_DEFAULT smokedec_debug

/* SmokeDec signals and args */
enum
{
  LAST_SIGNAL
};

enum
{
  PROP_0
};

static void gst_smokedec_base_init (gpointer g_class);
static void gst_smokedec_class_init (GstSmokeDec * klass);
static void gst_smokedec_init (GstSmokeDec * smokedec);
static void gst_smokedec_finalize (GObject * object);

static GstStateChangeReturn
gst_smokedec_change_state (GstElement * element, GstStateChange transition);

static GstFlowReturn gst_smokedec_chain (GstPad * pad, GstBuffer * buf);

static GstElementClass *parent_class = NULL;

/*static guint gst_smokedec_signals[LAST_SIGNAL] = { 0 }; */

GType
gst_smokedec_get_type (void)
{
  static GType smokedec_type = 0;

  if (!smokedec_type) {
    static const GTypeInfo smokedec_info = {
      sizeof (GstSmokeDecClass),
      gst_smokedec_base_init,
      NULL,
      (GClassInitFunc) gst_smokedec_class_init,
      NULL,
      NULL,
      sizeof (GstSmokeDec),
      0,
      (GInstanceInitFunc) gst_smokedec_init,
    };

    smokedec_type =
        g_type_register_static (GST_TYPE_ELEMENT, "GstSmokeDec", &smokedec_info,
        0);
  }
  return smokedec_type;
}

static GstStaticPadTemplate gst_smokedec_src_pad_template =
GST_STATIC_PAD_TEMPLATE ("src",
    GST_PAD_SRC,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS (GST_VIDEO_CAPS_YUV ("I420"))
    );

static GstStaticPadTemplate gst_smokedec_sink_pad_template =
GST_STATIC_PAD_TEMPLATE ("sink",
    GST_PAD_SINK,
    GST_PAD_ALWAYS,
    GST_STATIC_CAPS ("video/x-smoke, "
        "width = (int) [ 16, 4096 ], "
        "height = (int) [ 16, 4096 ], " "framerate = (fraction) [ 0/1, MAX ]")
    );

static void
gst_smokedec_base_init (gpointer g_class)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

  gst_element_class_add_static_pad_template (element_class,
      &gst_smokedec_src_pad_template);
  gst_element_class_add_static_pad_template (element_class,
      &gst_smokedec_sink_pad_template);
  gst_element_class_set_static_metadata (element_class, "Smoke video decoder",
      "Codec/Decoder/Video", "Decode video from Smoke format",
      "Wim Taymans <wim@fluendo.com>");
}

static void
gst_smokedec_class_init (GstSmokeDec * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;

  parent_class = g_type_class_peek_parent (klass);

  gobject_class->finalize = gst_smokedec_finalize;

  gstelement_class->change_state =
      GST_DEBUG_FUNCPTR (gst_smokedec_change_state);

  GST_DEBUG_CATEGORY_INIT (smokedec_debug, "smokedec", 0, "Smoke decoder");
}

static void
gst_smokedec_init (GstSmokeDec * smokedec)
{
  GST_DEBUG_OBJECT (smokedec, "gst_smokedec_init: initializing");
  /* create the sink and src pads */

  smokedec->sinkpad =
      gst_pad_new_from_static_template (&gst_smokedec_sink_pad_template,
      "sink");
  gst_pad_set_chain_function (smokedec->sinkpad, gst_smokedec_chain);
  gst_element_add_pad (GST_ELEMENT (smokedec), smokedec->sinkpad);

  smokedec->srcpad =
      gst_pad_new_from_static_template (&gst_smokedec_src_pad_template, "src");
  gst_pad_use_fixed_caps (smokedec->srcpad);
  gst_element_add_pad (GST_ELEMENT (smokedec), smokedec->srcpad);

  smokecodec_decode_new (&smokedec->info);
}

static void
gst_smokedec_finalize (GObject * object)
{
  GstSmokeDec *dec = GST_SMOKEDEC (object);

  smokecodec_info_free (dec->info);

  G_OBJECT_CLASS (parent_class)->finalize (object);
}

static GstFlowReturn
gst_smokedec_chain (GstPad * pad, GstBuffer * buf)
{
  GstSmokeDec *smokedec;
  guint8 *data, *outdata;
  gulong size, outsize;
  GstBuffer *outbuf;
  SmokeCodecFlags flags;
  GstClockTime time;
  guint width, height;
  guint fps_num, fps_denom;
  gint smokeret;
  GstFlowReturn ret;

  smokedec = GST_SMOKEDEC (gst_pad_get_parent (pad));

  data = GST_BUFFER_DATA (buf);
  size = GST_BUFFER_SIZE (buf);
  time = GST_BUFFER_TIMESTAMP (buf);

  if (size < 1)
    goto too_small;

  GST_LOG_OBJECT (smokedec, "got buffer of %lu bytes", size);

  /* have the ID packet. */
  if (data[0] == SMOKECODEC_TYPE_ID) {
    smokeret = smokecodec_parse_id (smokedec->info, data, size);
    if (smokeret != SMOKECODEC_OK)
      goto header_error;

    ret = GST_FLOW_OK;
    goto done;
  }

  /* now handle data packets */
  GST_DEBUG_OBJECT (smokedec, "reading header %08lx", *(gulong *) data);
  smokecodec_parse_header (smokedec->info, data, size, &flags, &width, &height,
      &fps_num, &fps_denom);

  if (smokedec->height != height || smokedec->width != width ||
      smokedec->fps_num != fps_num || smokedec->fps_denom != fps_denom) {
    GstCaps *caps;

    GST_DEBUG_OBJECT (smokedec, "parameter change: %dx%d @ %d/%dfps",
        width, height, fps_num, fps_denom);

    smokedec->height = height;
    smokedec->width = width;

    caps = gst_caps_new_simple ("video/x-raw-yuv",
        "format", GST_TYPE_FOURCC, GST_MAKE_FOURCC ('I', '4', '2', '0'),
        "width", G_TYPE_INT, width,
        "height", G_TYPE_INT, height,
        "framerate", GST_TYPE_FRACTION, fps_num, fps_denom, NULL);

    gst_pad_set_caps (smokedec->srcpad, caps);
    gst_caps_unref (caps);
  }

  if (smokedec->need_keyframe) {
    if (!(flags & SMOKECODEC_KEYFRAME))
      goto keyframe_skip;

    smokedec->need_keyframe = FALSE;
  }

  outsize = width * height + width * height / 2;
  outbuf = gst_buffer_new_and_alloc (outsize);
  outdata = GST_BUFFER_DATA (outbuf);

  GST_BUFFER_DURATION (outbuf) =
      gst_util_uint64_scale_int (GST_SECOND, fps_denom, fps_num);
  GST_BUFFER_OFFSET (outbuf) = GST_BUFFER_OFFSET (buf);
  gst_buffer_set_caps (outbuf, GST_PAD_CAPS (smokedec->srcpad));

  if (time == GST_CLOCK_TIME_NONE) {
    if (GST_BUFFER_OFFSET (buf) == -1) {
      time = smokedec->next_time;
    } else {
      time = GST_BUFFER_OFFSET (buf) * GST_BUFFER_DURATION (outbuf);
    }
  }
  GST_BUFFER_TIMESTAMP (outbuf) = time;
  if (time != -1)
    smokedec->next_time = time + GST_BUFFER_DURATION (outbuf);
  else
    smokedec->next_time = -1;

  smokeret = smokecodec_decode (smokedec->info, data, size, outdata);
  if (smokeret != SMOKECODEC_OK)
    goto decode_error;

  GST_DEBUG_OBJECT (smokedec, "gst_smokedec_chain: sending buffer");
  ret = gst_pad_push (smokedec->srcpad, outbuf);

done:
  gst_buffer_unref (buf);
  gst_object_unref (smokedec);

  return ret;

  /* ERRORS */
too_small:
  {
    GST_ELEMENT_ERROR (smokedec, STREAM, DECODE,
        (NULL), ("Input buffer too small"));
    ret = GST_FLOW_ERROR;
    goto done;
  }
header_error:
  {
    GST_ELEMENT_ERROR (smokedec, STREAM, DECODE,
        (NULL), ("Could not parse smoke header, reason: %d", smokeret));
    ret = GST_FLOW_ERROR;
    goto done;
  }
keyframe_skip:
  {
    GST_DEBUG_OBJECT (smokedec, "dropping buffer while waiting for keyframe");
    ret = GST_FLOW_OK;
    goto done;
  }
decode_error:
  {
    GST_ELEMENT_ERROR (smokedec, STREAM, DECODE,
        (NULL), ("Could not decode smoke frame, reason: %d", smokeret));
    ret = GST_FLOW_ERROR;
    goto done;
  }
}

static GstStateChangeReturn
gst_smokedec_change_state (GstElement * element, GstStateChange transition)
{
  GstStateChangeReturn ret;
  GstSmokeDec *dec;

  dec = GST_SMOKEDEC (element);

  switch (transition) {
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      /* reset the initial video state */
      dec->format = -1;
      dec->width = -1;
      dec->height = -1;
      dec->fps_num = -1;
      dec->fps_denom = -1;
      dec->next_time = 0;
    default:
      break;
  }

  ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
  if (ret != GST_STATE_CHANGE_SUCCESS)
    return ret;

  switch (transition) {
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      break;
    default:
      break;
  }

  return ret;
}