Esempi in C++ (Cpp) per gst_pngdec_caps_create_and_set

Esempio n. 1

File: gstpngdec.c Progetto: DylanZA/gst-plugins-good

static void
user_info_callback (png_structp png_ptr, png_infop info)
{
  GstPngDec *pngdec = NULL;
  GstFlowReturn ret;

  GST_LOG ("info ready");

  pngdec = GST_PNGDEC (png_get_io_ptr (png_ptr));
  /* Generate the caps and configure */
  ret = gst_pngdec_caps_create_and_set (pngdec);
  if (ret != GST_FLOW_OK) {
    goto beach;
  }

  /* Allocate output buffer */
  ret =
      gst_video_decoder_allocate_output_frame (GST_VIDEO_DECODER (pngdec),
      pngdec->current_frame);
  if (G_UNLIKELY (ret != GST_FLOW_OK))
    GST_DEBUG_OBJECT (pngdec, "failed to acquire buffer");

beach:
  pngdec->ret = ret;
}

Esempio n. 2

static void
user_info_callback (png_structp png_ptr, png_infop info)
{
  GstPngDec *pngdec = NULL;
  GstFlowReturn ret = GST_FLOW_OK;
  size_t buffer_size;
  GstBuffer *buffer = NULL;

  pngdec = GST_PNGDEC (png_ptr->io_ptr);

  GST_LOG ("info ready");

  /* Generate the caps and configure */
  ret = gst_pngdec_caps_create_and_set (pngdec);
  if (ret != GST_FLOW_OK) {
    goto beach;
  }

  /* Allocate output buffer */
  pngdec->rowbytes = png_get_rowbytes (pngdec->png, pngdec->info);
  buffer_size = pngdec->height * GST_ROUND_UP_4 (pngdec->rowbytes);
  ret =
      gst_pad_alloc_buffer_and_set_caps (pngdec->srcpad, GST_BUFFER_OFFSET_NONE,
      buffer_size, GST_PAD_CAPS (pngdec->srcpad), &buffer);
  if (ret != GST_FLOW_OK) {
    goto beach;
  }

  pngdec->buffer_out = buffer;

beach:
  pngdec->ret = ret;
}

Esempio n. 3

File: gstpngdec.c Progetto: JJCG/gst-plugins-good

static void
gst_pngdec_task (GstPad * pad)
{
  GstPngDec *pngdec;
  GstBuffer *buffer = NULL;
  size_t buffer_size = 0;
  gint i = 0;
  png_bytep *rows, inp;
  png_uint_32 rowbytes;
  GstFlowReturn ret = GST_FLOW_OK;

  pngdec = GST_PNGDEC (GST_OBJECT_PARENT (pad));

  GST_LOG_OBJECT (pngdec, "read frame");

  /* Let libpng come back here on error */
  if (setjmp (png_jmpbuf (pngdec->png))) {
    ret = GST_FLOW_ERROR;
    goto pause;
  }

  /* Set reading callback */
  png_set_read_fn (pngdec->png, pngdec, user_read_data);

  /* Read info */
  png_read_info (pngdec->png, pngdec->info);

  /* Generate the caps and configure */
  ret = gst_pngdec_caps_create_and_set (pngdec);
  if (ret != GST_FLOW_OK) {
    goto pause;
  }

  /* Allocate output buffer */
  rowbytes = png_get_rowbytes (pngdec->png, pngdec->info);
  if (rowbytes > (G_MAXUINT32 - 3) || pngdec->height > G_MAXUINT32 / rowbytes) {
    ret = GST_FLOW_ERROR;
    goto pause;
  }
  rowbytes = GST_ROUND_UP_4 (rowbytes);
  buffer_size = pngdec->height * rowbytes;
  ret =
      gst_pad_alloc_buffer_and_set_caps (pngdec->srcpad, GST_BUFFER_OFFSET_NONE,
      buffer_size, GST_PAD_CAPS (pngdec->srcpad), &buffer);
  if (ret != GST_FLOW_OK)
    goto pause;

  rows = (png_bytep *) g_malloc (sizeof (png_bytep) * pngdec->height);

  inp = GST_BUFFER_DATA (buffer);

  for (i = 0; i < pngdec->height; i++) {
    rows[i] = inp;
    inp += rowbytes;
  }

  /* Read the actual picture */
  png_read_image (pngdec->png, rows);
  g_free (rows);

  /* Push the raw RGB frame */
  ret = gst_pad_push (pngdec->srcpad, buffer);
  if (ret != GST_FLOW_OK)
    goto pause;

  /* And we are done */
  gst_pad_pause_task (pngdec->sinkpad);
  gst_pad_push_event (pngdec->srcpad, gst_event_new_eos ());
  return;

pause:
  {
    GST_INFO_OBJECT (pngdec, "pausing task, reason %s",
        gst_flow_get_name (ret));
    gst_pad_pause_task (pngdec->sinkpad);
    if (GST_FLOW_IS_FATAL (ret) || ret == GST_FLOW_NOT_LINKED) {
      GST_ELEMENT_ERROR (pngdec, STREAM, FAILED,
          (_("Internal data stream error.")),
          ("stream stopped, reason %s", gst_flow_get_name (ret)));
      gst_pad_push_event (pngdec->srcpad, gst_event_new_eos ());
    }
  }
}