/* GStreamer

  * Copyright (C) <2006> Renato Araujo Oliveira Filho <renato.filho@indt.org.br>

  *                      Rosfran Borges <rosfran.borges@indt.org.br>

  *

  * 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.

  */

 /* Element-Checklist-Version: 5 */

 /**

  * SECTION:element-nuvdemux

  *

  * <refsect2>

  * <para>

  * Demuxes an .nuv file into raw or compressed audio and/or video streams.

  * </para>

  * <para>

  * This element currently only supports pull-based scheduling.

  * </para>

  * <title>Example launch line</title>

  * <para>

  * <programlisting>

  * gst-launch filesrc test.nuv ! nuvdemux name=demux  demux.audio_00 ! decodebin ! audioconvert ! audioresample ! autoaudiosink   demux.video_00 ! queue ! decodebin ! ffmpegcolorspace ! videoscale ! autovideosink

  * </programlisting>

  * Play (parse and decode) an .nuv file and try to output it to

  * an automatically detected soundcard and videosink. If the NUV file contains

  * compressed audio or video data, this will only work if you have the

  * right decoder elements/plugins installed.

  * </para>

  * </refsect2>

  *

  */

 #ifdef HAVE_CONFIG_H

 #include "config.h"

 #endif

 #include <gst/gst.h>

 #include <gst/gsterror.h>

 #include <gst/gstplugin.h>

 #include <string.h>

 #include "glib/gi18n.h"

 #include "gstnuvdemux.h"

 GST_DEBUG_CATEGORY_STATIC (nuvdemux_debug);

 #define GST_CAT_DEFAULT nuvdemux_debug

 #define GST_FLOW_ERROR_NO_DATA  -101

 GST_DEBUG_CATEGORY_EXTERN (GST_CAT_EVENT);

 static const GstElementDetails gst_nuv_demux_details =

 GST_ELEMENT_DETAILS ("Nuv demuxer",

     "Codec/Demuxer",

     "Demultiplex a .nuv file into audio and video",

     "Renato Araujo Oliveira Filho <renato.filho@indt.org.br>,"

     "Rosfran Borges <rosfran.borges@indt.org.br>");

 static GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",

     GST_PAD_SINK,

     GST_PAD_ALWAYS,

     GST_STATIC_CAPS ("video/x-nuv"));

 static GstStaticPadTemplate audio_src_template =

 GST_STATIC_PAD_TEMPLATE ("audio_src",

     GST_PAD_SRC,

     GST_PAD_SOMETIMES,

     GST_STATIC_CAPS_ANY);

 static GstStaticPadTemplate video_src_template =

 GST_STATIC_PAD_TEMPLATE ("video_src",

     GST_PAD_SRC,

     GST_PAD_SOMETIMES,

     GST_STATIC_CAPS_ANY);

 /* NUV Demux plug-in time-line functions */

 static void gst_nuv_demux_finalize (GObject * object);

 static GstStateChangeReturn gst_nuv_demux_change_state (GstElement * element,

     GstStateChange transition);

 static void gst_nuv_demux_loop (GstPad * pad);

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

 static GstFlowReturn gst_nuv_demux_play (GstPad * pad);

 static gboolean gst_nuv_demux_sink_activate_pull (GstPad * sinkpad,

     gboolean active);

 static gboolean gst_nuv_demux_sink_activate_push (GstPad * pad, 

     gboolean active);

 static gboolean gst_nuv_demux_sink_activate (GstPad * sinkpad);

 static GstFlowReturn gst_nuv_demux_read_bytes (GstNuvDemux * nuv, guint64 size,

     gboolean move, GstBuffer ** buffer);

 static void gst_nuv_demux_reset (GstNuvDemux * nuv);

 static void gst_nuv_demux_destoy_src_pad (GstNuvDemux * nuv);

 static void gst_nuv_demux_send_eos (GstNuvDemux * nuv);

 /* GObject methods */

 GST_BOILERPLATE (GstNuvDemux, gst_nuv_demux, GstElement, GST_TYPE_ELEMENT);

 #if G_BYTE_ORDER == G_BIG_ENDIAN

 static inline gdouble

 _gdouble_swap_le_be (gdouble * d)

 {

   union

   {

     guint64 i;

     gdouble d;

   } u;

   u.d = *d;

   u.i = GUINT64_SWAP_LE_BE (u.i);

   return u.d;

 }

 #define READ_DOUBLE_FROM_LE(d) (_gdouble_swap_le_be((gdouble* ) d))

 #else /* G_BYTE_ORDER != G_BIG_ENDIAN */

 #define READ_DOUBLE_FROM_LE(d) *((gdouble* ) (d))

 #endif /* G_BYTE_ORDER != G_BIG_ENDIAN */

 static void

 gst_nuv_demux_base_init (gpointer klass)

 {

   GstElementClass *element_class = GST_ELEMENT_CLASS (klass);

   gst_element_class_add_pad_template (element_class,

       gst_static_pad_template_get (&audio_src_template));

   gst_element_class_add_pad_template (element_class,

       gst_static_pad_template_get (&video_src_template));

   gst_element_class_add_pad_template (element_class,

       gst_static_pad_template_get (&sink_template));

   gst_element_class_set_details (element_class, &gst_nuv_demux_details);

 }

 static void

 gst_nuv_demux_class_init (GstNuvDemuxClass * klass)

 {

   GstElementClass *gstelement_class = GST_ELEMENT_CLASS (klass);

   GObjectClass *gobject_class = (GObjectClass *) klass;

   GST_DEBUG_CATEGORY_INIT (nuvdemux_debug, "nuvdemux",

       0, "Demuxer for NUV streams");

   parent_class = g_type_class_peek_parent (klass);

   gobject_class->finalize = gst_nuv_demux_finalize;

   gstelement_class->change_state = gst_nuv_demux_change_state;

 }

 static void

 gst_nuv_demux_init (GstNuvDemux * nuv, GstNuvDemuxClass * nuv_class)

 {

   nuv->sinkpad = gst_pad_new_from_static_template (&sink_template, "sink");

   gst_pad_set_activate_function (nuv->sinkpad, gst_nuv_demux_sink_activate);

   gst_pad_set_activatepull_function (nuv->sinkpad,

       gst_nuv_demux_sink_activate_pull);

   gst_pad_set_activatepush_function (nuv->sinkpad, 

       gst_nuv_demux_sink_activate_push);

   gst_pad_set_chain_function (nuv->sinkpad,

       GST_DEBUG_FUNCPTR (gst_nuv_demux_chain));

   gst_element_add_pad (GST_ELEMENT (nuv), nuv->sinkpad);

   gst_nuv_demux_index_init( &nuv->index_entries );

   nuv->adapter = NULL;

   nuv->mpeg_buffer = NULL;

   nuv->h = NULL;

   nuv->eh = NULL;

   nuv->fh = NULL;

   gst_nuv_demux_reset (nuv);

 }

 static void

 gst_nuv_demux_finalize (GObject * object)

 {

   GstNuvDemux *nuv = GST_NUV_DEMUX (object);

   if (nuv->mpeg_buffer != NULL) {

     gst_buffer_unref (nuv->mpeg_buffer);

   }

   if ( nuv->index_entries != NULL ) {

   	gst_nuv_demux_index_clean( &nuv->index_entries );

   	nuv->index_entries = NULL;

   }

   gst_nuv_demux_destoy_src_pad (nuv);

   gst_nuv_demux_reset (nuv);

   if (nuv->adapter != NULL) {

     gst_object_unref (nuv->adapter);

   }

   G_OBJECT_CLASS (parent_class)->finalize (object);

 }

 /* HeaderLoad:

  */

 static GstFlowReturn

 gst_nuv_demux_header_load (GstNuvDemux * nuv, nuv_header ** h_ret)

 {

   GstBuffer *buffer = NULL;

   GstFlowReturn res = gst_nuv_demux_read_bytes (nuv, 72, TRUE, &buffer);

   if (res != GST_FLOW_OK)

     return res;

   nuv_header *h = g_new0 (nuv_header, 1);

   memcpy (h->id, buffer->data, 12);

   memcpy (h->version, buffer->data + 12, 5);

   h->i_width = GST_READ_UINT32_LE (&buffer->data[20]);

   h->i_height = GST_READ_UINT32_LE (&buffer->data[24]);

   h->i_width_desired = GST_READ_UINT32_LE (&buffer->data[28]);

   h->i_height_desired = GST_READ_UINT32_LE (&buffer->data[32]);

   h->i_mode = GPOINTER_TO_INT (buffer->data[36]);

   h->d_aspect = READ_DOUBLE_FROM_LE (&buffer->data[40]);

   h->d_fps = READ_DOUBLE_FROM_LE (&buffer->data[48]);

   h->i_video_blocks = GST_READ_UINT32_LE (&buffer->data[56]);

   h->i_audio_blocks = GST_READ_UINT32_LE (&buffer->data[60]);

   h->i_text_blocks = GST_READ_UINT32_LE (&buffer->data[64]);

   h->i_keyframe_distance = GST_READ_UINT32_LE (&buffer->data[68]);

   GST_DEBUG_OBJECT (nuv,

       "nuv: h=%s v=%s %dx%d a=%f fps=%f v=%d a=%d t=%d kfd=%d", h->id,

       h->version, h->i_width, h->i_height, h->d_aspect, h->d_fps,

       h->i_video_blocks, h->i_audio_blocks, h->i_text_blocks,

       h->i_keyframe_distance);

   *h_ret = h;

   gst_buffer_unref (buffer);

   return res;

 }

 static GstFlowReturn

 gst_nuv_demux_stream_header_data (GstNuvDemux * nuv)

 {

   GstFlowReturn res = gst_nuv_demux_header_load (nuv, &nuv->h);

   if (res == GST_FLOW_OK)

     nuv->state = GST_NUV_DEMUX_EXTRA_DATA;

   return res;

 }

 /*

  * Read NUV file tag

  */

 static GstFlowReturn

 gst_nuv_demux_stream_file_header (GstNuvDemux * nuv)

 {

   GstFlowReturn res = GST_FLOW_OK;

   GstBuffer *file_header = NULL;

   res = gst_nuv_demux_read_bytes (nuv, 12, FALSE, &file_header);

   if (res != GST_FLOW_OK) {

     return res;

   } else {

     if (strncmp ((gchar *) file_header->data, "MythTVVideo", 11) ||

         strncmp ((gchar *) file_header->data, "NuppelVideo", 11)) {

       nuv->state = GST_NUV_DEMUX_HEADER_DATA;

     } else {

       GST_DEBUG_OBJECT (nuv, "error parsing file header");

       nuv->state = GST_NUV_DEMUX_INVALID_DATA;

       res = GST_FLOW_ERROR;

     }

   }

   if (file_header != NULL) {

     gst_buffer_unref (file_header);

   }

   return res;

 }

 /* FrameHeaderLoad:

  */

 static GstFlowReturn

 gst_nuv_demux_frame_header_load (GstNuvDemux * nuv, nuv_frame_header ** h_ret)

 {

   unsigned char *data;

   nuv_frame_header *h;

   GstBuffer *buf = NULL;

   GstFlowReturn res = gst_nuv_demux_read_bytes (nuv, 12, TRUE, &buf);

   if (res != GST_FLOW_OK) {

     if (buf != NULL) {

       gst_buffer_unref (buf);

     }

     return res;

   }

   h = g_new0 (nuv_frame_header, 1);

   data = buf->data;

   h->i_type = GPOINTER_TO_INT (data[0]);

   h->i_compression = GPOINTER_TO_INT (data[1]);

   h->i_keyframe = GPOINTER_TO_INT (data[2]);

   h->i_filters = GPOINTER_TO_INT (data[3]);

   h->i_timecode = GST_READ_UINT32_LE (&data[4]);

   h->i_length = GST_READ_UINT32_LE (&data[8]);

   GST_DEBUG_OBJECT (nuv, "frame hdr: t=%c c=%c k=%d f=0x%x timecode=%d l=%d",

       h->i_type,

       h->i_compression ? h->i_compression : ' ',

       h->i_keyframe ? h->i_keyframe : ' ',

       h->i_filters, h->i_timecode, h->i_length);

   *h_ret = h;

   gst_buffer_unref (buf);

   return GST_FLOW_OK;

 }

 static GstFlowReturn

 gst_nuv_demux_extended_header_load (GstNuvDemux * nuv,

     nuv_extended_header ** h_ret)

 {

   unsigned char *data;

   GstBuffer *buff = NULL;

   nuv_extended_header *h;

   GstFlowReturn res = gst_nuv_demux_read_bytes (nuv, 512, TRUE, &buff);

   if (res != GST_FLOW_OK) {

     if (buff != NULL) {

       gst_buffer_unref (buff);

     }

     return res;

   }

   h = g_new0 (nuv_extended_header, 1);

   data = buff->data;

   h->i_version = GST_READ_UINT32_LE (&data[0]);

   h->i_video_fcc = GST_MAKE_FOURCC (data[4], data[5], data[6], data[7]);

   h->i_audio_fcc = GST_MAKE_FOURCC (data[8], data[9], data[10], data[11]);

   h->i_audio_sample_rate = GST_READ_UINT32_LE (&data[12]);

   h->i_audio_bits_per_sample = GST_READ_UINT32_LE (&data[16]);

   h->i_audio_channels = GST_READ_UINT32_LE (&data[20]);

   h->i_audio_compression_ratio = GST_READ_UINT32_LE (&data[24]);

   h->i_audio_quality = GST_READ_UINT32_LE (&data[28]);

   h->i_rtjpeg_quality = GST_READ_UINT32_LE (&data[32]);

   h->i_rtjpeg_luma_filter = GST_READ_UINT32_LE (&data[36]);

   h->i_rtjpeg_chroma_filter = GST_READ_UINT32_LE (&data[40]);

   h->i_lavc_bitrate = GST_READ_UINT32_LE (&data[44]);

   h->i_lavc_qmin = GST_READ_UINT32_LE (&data[48]);

   h->i_lavc_qmin = GST_READ_UINT32_LE (&data[52]);

   h->i_lavc_maxqdiff = GST_READ_UINT32_LE (&data[56]);

   h->i_seekable_offset = GST_READ_UINT64_LE (&data[60]);

   h->i_keyframe_adjust_offset = GST_READ_UINT64_LE (&data[68]);

   GST_DEBUG_OBJECT (nuv,

       "ex hdr: v=%d vffc=%4.4s afcc=%4.4s %dHz %dbits ach=%d acr=%d aq=%d"

       "rtjpeg q=%d lf=%d lc=%d lavc br=%d qmin=%d qmax=%d maxqdiff=%d seekableoff=%lld keyfao=%lld",

       h->i_version, (gchar *) & h->i_video_fcc, (gchar *) & h->i_audio_fcc,

       h->i_audio_sample_rate, h->i_audio_bits_per_sample, h->i_audio_channels,

       h->i_audio_compression_ratio, h->i_audio_quality, h->i_rtjpeg_quality,

       h->i_rtjpeg_luma_filter, h->i_rtjpeg_chroma_filter, h->i_lavc_bitrate,

       h->i_lavc_qmin, h->i_lavc_qmax, h->i_lavc_maxqdiff, h->i_seekable_offset,

       h->i_keyframe_adjust_offset);

   *h_ret = h;

   gst_buffer_unref (buff);

   return res;

 }

 static void

 gst_nuv_demux_create_pads (GstNuvDemux * nuv)

 {

   if (nuv->h->i_video_blocks != 0) {

     GstCaps *video_caps = NULL;

     nuv->src_video_pad =

         gst_pad_new_from_static_template (&video_src_template, "video_src");

     video_caps = gst_caps_new_simple ("video/x-divx",

         "divxversion", G_TYPE_INT, 4,

         "width", G_TYPE_INT, nuv->h->i_width,

         "height", G_TYPE_INT, nuv->h->i_height,

         "framerate", GST_TYPE_FRACTION, (gint) (nuv->h->d_fps * 1000.0f), 1000,

         "format", GST_TYPE_FOURCC, nuv->eh->i_video_fcc,

         "pixel-aspect-ratio", GST_TYPE_FRACTION,

         (gint) (nuv->h->d_aspect * 1000.0f), 1000, NULL);

     gst_pad_use_fixed_caps (nuv->src_video_pad);

     gst_pad_set_caps (nuv->src_video_pad, video_caps);

     gst_pad_set_active (nuv->src_video_pad, TRUE);

     gst_element_add_pad (GST_ELEMENT (nuv), nuv->src_video_pad);

     gst_caps_unref (video_caps);

   }

   if (nuv->h->i_audio_blocks != 0) {

     GstCaps *audio_caps = NULL;

     nuv->src_audio_pad =

         gst_pad_new_from_static_template (&audio_src_template, "audio_src");

     audio_caps = gst_caps_new_simple ("audio/mpeg",

         "rate", G_TYPE_INT, nuv->eh->i_audio_sample_rate,

         "format", GST_TYPE_FOURCC, nuv->eh->i_audio_fcc,

         "channels", G_TYPE_INT, nuv->eh->i_audio_channels,

         "mpegversion", G_TYPE_INT, nuv->eh->i_version, NULL);

     gst_pad_use_fixed_caps (nuv->src_audio_pad);

     gst_pad_set_caps (nuv->src_audio_pad, audio_caps);

     gst_pad_set_active (nuv->src_audio_pad, TRUE);

     gst_element_add_pad (GST_ELEMENT (nuv), nuv->src_audio_pad);

     gst_caps_unref (audio_caps);

   }

   gst_element_no_more_pads (GST_ELEMENT (nuv));

 }

 static GstFlowReturn

 gst_nuv_demux_read_head_frame (GstNuvDemux * nuv)

 {

   GstFlowReturn ret = GST_FLOW_OK;

   if (nuv->fh != NULL) 

   {

     g_free (nuv->fh);

     nuv->fh = NULL;

   }

   ret = gst_nuv_demux_frame_header_load (nuv, &nuv->fh);

   if (ret != GST_FLOW_OK)

     return ret;

   nuv->state = GST_NUV_DEMUX_MOVI;

   return ret;

 }

 static GstFlowReturn

 gst_nuv_demux_stream_data (GstNuvDemux * nuv)

 {

   GstFlowReturn ret = GST_FLOW_OK;

   GstBuffer *buf = NULL;

   nuv_frame_header *h = nuv->fh;

   if (h->i_type == 'R')

     goto done;

   if (h->i_length > 0) {

 	  ret = gst_nuv_demux_read_bytes (nuv, h->i_length, TRUE, &buf);

 	  if (ret != GST_FLOW_OK)

 		  return ret;

       if ((h->i_type == 'V') || (h->i_type == 'A')) {

         if (h->i_timecode < 0) {

             nuv->last_time = 1;

             h->i_timecode = 0;

         }

         else if (nuv->last_time == 1)

         {

           nuv->last_time = 0;

           gst_pad_push_event (nuv->src_video_pad,

               gst_event_new_new_segment (TRUE, 1.0, GST_FORMAT_TIME, 0, 

               		GST_CLOCK_TIME_NONE, 0));

           gst_pad_push_event (nuv->src_audio_pad,

               gst_event_new_new_segment (TRUE, 1.0, GST_FORMAT_TIME, 0, 

               		GST_CLOCK_TIME_NONE, 0));

         }

         GST_BUFFER_TIMESTAMP (buf) = h->i_timecode * GST_MSECOND;

       }    

   }

   switch (h->i_type) {

     case 'V':

     {

       if (h->i_length == 0)

         break;

       if ( !gst_pad_is_linked( nuv->src_video_pad ) )

       	break;

       GST_BUFFER_SIZE (buf) = h->i_length;

       gst_buffer_set_caps (buf, GST_PAD_CAPS (nuv->src_video_pad));

       ret = gst_pad_push (nuv->src_video_pad, buf);

       if (ret != GST_FLOW_OK) {

         GST_WARNING_OBJECT (nuv, "error pushing on srcpad %s, is linked? = %d",

             gst_pad_get_name (nuv->src_video_pad), gst_pad_is_linked (nuv->src_video_pad));

       }

       break;

     }

     case 'A':

     {

       if (h->i_length == 0)

         break;

       if ( !gst_pad_is_linked( nuv->src_audio_pad ) )

       	break;

       GST_BUFFER_SIZE (buf) = h->i_length;

       gst_buffer_set_caps (buf, GST_PAD_CAPS (nuv->src_audio_pad));

       ret = gst_pad_push (nuv->src_audio_pad, buf);

       if (ret != GST_FLOW_OK) {

         GST_WARNING_OBJECT (nuv, "Error pushing on srcpad %s, is linked? = %d",

             gst_pad_get_name (nuv->src_audio_pad), gst_pad_is_linked (nuv->src_audio_pad));

       }

       break;

     }

     case 'S':

     {

       switch (h->i_compression) {

         case 'V':

 		  if ( !gst_pad_is_linked( nuv->src_video_pad ) )

 		    break;

           GST_DEBUG_OBJECT (nuv, "sending new video segment: %d", h->i_timecode);

           gst_pad_push_event (nuv->src_video_pad,

               gst_event_new_new_segment (TRUE, 1.0, GST_FORMAT_TIME, h->i_timecode * GST_MSECOND, 

               		GST_CLOCK_TIME_NONE, 0));

           break;

         case 'A':        

 		      if ( !gst_pad_is_linked( nuv->src_audio_pad ) )

 		      	break;

           GST_DEBUG_OBJECT (nuv, "sending new audio segment: %d", h->i_timecode);

           gst_pad_push_event (nuv->src_audio_pad,

               gst_event_new_new_segment (TRUE, 1.0, GST_FORMAT_TIME, 0, 

               		GST_CLOCK_TIME_NONE, 0));

           break;

         default:

           break;

       }

       if (buf != NULL)

         gst_buffer_unref (buf);

     }

     default:

       if (buf != NULL)

         gst_buffer_unref (buf);

       break;

   }

 done:

   nuv->state = GST_NUV_DEMUX_FRAME_HEADER;

   g_free (nuv->fh);

   nuv->fh = NULL;

   return ret;

 }

 static GstFlowReturn

 gst_nuv_demux_stream_mpeg_data (GstNuvDemux * nuv)

 {

   GstFlowReturn ret = GST_FLOW_OK;

   /* ffmpeg extra data */

   ret =

       gst_nuv_demux_read_bytes (nuv, nuv->mpeg_data_size, TRUE,

       &nuv->mpeg_buffer);

   if (ret != GST_FLOW_OK) {

     return ret; 

   }

   GST_BUFFER_SIZE (nuv->mpeg_buffer) = nuv->mpeg_data_size;

   nuv->state = GST_NUV_DEMUX_EXTEND_HEADER;

   return ret;

 }

 static GstFlowReturn

 gst_nuv_demux_stream_extra_data (GstNuvDemux * nuv)

 {

   GstFlowReturn ret = GST_FLOW_OK;

   /* Load 'D' */

   nuv_frame_header *h;

   ret = gst_nuv_demux_frame_header_load (nuv, &h);

   if (ret != GST_FLOW_OK)

     return ret;

   if (h->i_type != 'D') {

     g_free (h);

     return GST_FLOW_ERROR;

   }

   if (h->i_length > 0) {

     if (h->i_compression == 'F') {

       nuv->state = GST_NUV_DEMUX_MPEG_DATA;

     } else {

       g_free (h);

       return GST_FLOW_ERROR;

     }

   } else {

     nuv->state = GST_NUV_DEMUX_EXTEND_HEADER;

   }

   g_free (h);

   h = NULL;

   return ret;

 }

 static GstFlowReturn

 gst_nuv_demux_stream_extend_header_data (GstNuvDemux * nuv)

 {

   GstFlowReturn ret = GST_FLOW_OK;

   ret = gst_nuv_demux_extended_header_load (nuv, &nuv->eh);

   if (ret != GST_FLOW_OK)

     return ret;

   gst_nuv_demux_create_pads (nuv);

   nuv->state = GST_NUV_DEMUX_FRAME_HEADER;

   return ret;

 }

 static GstFlowReturn

 gst_nuv_demux_stream_extend_header (GstNuvDemux * nuv)

 {

   GstBuffer *buf = NULL;

   GstFlowReturn res = GST_FLOW_OK;

   res = gst_nuv_demux_read_bytes (nuv, 1, FALSE, &buf);

   if (res != GST_FLOW_OK) {

     if (buf != NULL) {

       gst_buffer_unref (buf);

     }

     return res;

   }

   if (buf->data[0] == 'X') {

     gst_buffer_unref (buf);

     buf = NULL;

     nuv_frame_header *h = NULL;

     res = gst_nuv_demux_frame_header_load (nuv, &h);

     if (res != GST_FLOW_OK)

       return res;

     if (h->i_length != 512) {

       g_free (h);

       return GST_FLOW_ERROR;

     }

     g_free (h);

     h = NULL;

     nuv->state = GST_NUV_DEMUX_EXTEND_HEADER_DATA;

   } else {

     nuv->state = GST_NUV_DEMUX_INVALID_DATA;

     g_object_unref (buf);

     GST_ELEMENT_WARNING (nuv, STREAM, FAILED,

         (_("incomplete NUV support")), ("incomplete NUV support"));

     return GST_FLOW_ERROR;

   }

   return res;

 }

 static GstFlowReturn

 gst_nuv_demux_play (GstPad * pad)

 {

   GstFlowReturn res = GST_FLOW_OK;

   GstNuvDemux *nuv = GST_NUV_DEMUX (GST_PAD_PARENT (pad));

   switch (nuv->state) {

     case GST_NUV_DEMUX_START:

       res = gst_nuv_demux_stream_file_header (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       if (nuv->state != GST_NUV_DEMUX_HEADER_DATA)

         break;

     case GST_NUV_DEMUX_HEADER_DATA:

       res = gst_nuv_demux_stream_header_data (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       if (nuv->state != GST_NUV_DEMUX_EXTRA_DATA)

         break;

     case GST_NUV_DEMUX_EXTRA_DATA:

       res = gst_nuv_demux_stream_extra_data (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       if (nuv->state != GST_NUV_DEMUX_MPEG_DATA)

         break;

     case GST_NUV_DEMUX_MPEG_DATA:

       res = gst_nuv_demux_stream_mpeg_data (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       if (nuv->state != GST_NUV_DEMUX_EXTEND_HEADER)

         break;

     case GST_NUV_DEMUX_EXTEND_HEADER:

       res = gst_nuv_demux_stream_extend_header (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       if (nuv->state != GST_NUV_DEMUX_EXTEND_HEADER_DATA)

         break;

     case GST_NUV_DEMUX_EXTEND_HEADER_DATA:

       res = gst_nuv_demux_stream_extend_header_data (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       if (nuv->state != GST_NUV_DEMUX_FRAME_HEADER)

         break;

     case GST_NUV_DEMUX_FRAME_HEADER:

       res = gst_nuv_demux_read_head_frame (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       if (nuv->state != GST_NUV_DEMUX_MOVI)

         break;

     case GST_NUV_DEMUX_MOVI:

       res = gst_nuv_demux_stream_data (nuv);

       if ((res != GST_FLOW_OK) && (res != GST_FLOW_ERROR_NO_DATA)) {

         goto pause;

       }

       break;

     case GST_NUV_DEMUX_INVALID_DATA:

       goto pause;

       break;

     default:

       g_assert_not_reached ();

   }

   GST_DEBUG_OBJECT (nuv, "state: %d res:%s", nuv->state,

       gst_flow_get_name (res));

   return GST_FLOW_OK;

 pause:

   GST_LOG_OBJECT (nuv, "pausing task, reason %s", gst_flow_get_name (res));

   gst_pad_pause_task (nuv->sinkpad);

   if (GST_FLOW_IS_FATAL (res)) {

     GST_ELEMENT_ERROR (nuv, STREAM, FAILED,

         (_("Internal data stream error.")),

         ("streaming stopped, reason %s", gst_flow_get_name (res)));

     gst_nuv_demux_send_eos (nuv);

   }

   return res;

 }

 static void

 gst_nuv_demux_send_eos (GstNuvDemux * nuv)

 {

   gst_element_post_message (GST_ELEMENT (nuv),

       gst_message_new_segment_done (GST_OBJECT (nuv), GST_FORMAT_TIME, -1));

   if (nuv->src_video_pad)

     gst_pad_push_event (nuv->src_video_pad, gst_event_new_eos ());

   if (nuv->src_audio_pad)

     gst_pad_push_event (nuv->src_audio_pad, gst_event_new_eos ());

 }

 static GstFlowReturn

 gst_nuv_demux_read_bytes (GstNuvDemux * nuv, guint64 size, gboolean move,

     GstBuffer ** buffer)

 {

   GstFlowReturn ret = GST_FLOW_OK;

   if (size == 0) {

     *buffer = gst_buffer_new ();

     return ret;

   }

   if (nuv->mode == 0) {

     ret = gst_pad_pull_range (nuv->sinkpad, nuv->offset, size, buffer);

     if (ret == GST_FLOW_OK) {

         if (move) {

 		    nuv->offset += size;

 		}

       /* got eos */

     } else if (ret == GST_FLOW_UNEXPECTED) {

       if (buffer != NULL)

           gst_buffer_unref (buffer);

       gst_nuv_demux_send_eos (nuv);

       return GST_FLOW_WRONG_STATE;

     }

   } else {

     if (gst_adapter_available (nuv->adapter) < size)

       return GST_FLOW_ERROR_NO_DATA;

     if (move) {

       guint8 *data = NULL;

       data = (guint8 *) gst_adapter_take (nuv->adapter, size);

       *buffer = gst_buffer_new ();

       gst_buffer_set_data (*buffer, data, size);

     } else {

       guint8 *data = NULL;

       data = (guint8 *) gst_adapter_peek (nuv->adapter, size);

       *buffer = gst_buffer_new ();

       gst_buffer_set_data (*buffer, data, size);

     }

   }

   return ret;

 }

 static gboolean

 gst_nuv_demux_sink_activate (GstPad * sinkpad)

 {

   gboolean res = TRUE;

   GstNuvDemux *nuv = GST_NUV_DEMUX (gst_pad_get_parent (sinkpad));

   if (gst_pad_check_pull_range (sinkpad)) {

     nuv->mode = 0;

     if (nuv->adapter) {

       gst_adapter_clear (nuv->adapter);

       g_object_unref (nuv->adapter);

       nuv->adapter = NULL;

     }

     res = gst_pad_activate_pull (sinkpad, TRUE);

   } else {

     nuv->mode = 1;

     if (nuv->adapter) {

       gst_adapter_clear (nuv->adapter);

     } else {

       nuv->adapter = gst_adapter_new ();

     }

     res = gst_pad_activate_push (sinkpad, TRUE);

   }

   g_object_unref (nuv);

   return res;

 }

 static gboolean

 gst_nuv_demux_sink_activate_pull (GstPad * sinkpad, gboolean active)

 {

   GstNuvDemux *nuv = GST_NUV_DEMUX (gst_pad_get_parent (sinkpad));

   if (active) {

     gst_pad_start_task (sinkpad, (GstTaskFunction) gst_nuv_demux_loop, sinkpad);

   } else {

     gst_pad_stop_task (sinkpad);

   }

   gst_object_unref (nuv);

   return TRUE;

 }

 static gboolean

 gst_nuv_demux_sink_activate_push (GstPad * pad, gboolean active)

 {

   GstNuvDemux *nuv = GST_NUV_DEMUX (gst_pad_get_parent (pad));

   if (active) {

     GST_DEBUG_OBJECT (nuv, "activating push/chain function");

   } else {

     GST_DEBUG_OBJECT (nuv, "deactivating push/chain function");

   }

   gst_object_unref (nuv);

   return TRUE;

 }

 static GstFlowReturn

 gst_nuv_demux_chain (GstPad * pad, GstBuffer * buf)

 {

   GstNuvDemux *nuv = GST_NUV_DEMUX (gst_pad_get_parent (pad));

   gst_adapter_push (nuv->adapter, buf);

   gst_object_unref (nuv);

   return gst_nuv_demux_play (pad);

 }

 static void

 gst_nuv_demux_loop (GstPad * pad)

 {

   gst_nuv_demux_play (pad);

 }

 static void

 gst_nuv_demux_reset (GstNuvDemux * nuv)

 {

   nuv->state = GST_NUV_DEMUX_START;

   nuv->mode = 0;

   nuv->offset = 0;

   nuv->last_time = 0;

   if (nuv->adapter != NULL)

     gst_adapter_clear (nuv->adapter);

   if (nuv->mpeg_buffer != NULL) {

     gst_buffer_unref (nuv->mpeg_buffer);

     nuv->mpeg_buffer = NULL;

   }

   g_free (nuv->h);

   nuv->h = NULL;

   g_free (nuv->eh);

   nuv->eh = NULL;

   g_free (nuv->fh);

   nuv->fh = NULL;

 }

 static void

 gst_nuv_demux_destoy_src_pad (GstNuvDemux * nuv)

 {

   if (nuv->src_video_pad) {

     gst_element_remove_pad (GST_ELEMENT (nuv), nuv->src_video_pad);

     nuv->src_video_pad = NULL;

   }

   if (nuv->src_audio_pad) {

     gst_element_remove_pad (GST_ELEMENT (nuv), nuv->src_audio_pad);

     nuv->src_audio_pad = NULL;

   }

 }

 static GstStateChangeReturn

 gst_nuv_demux_change_state (GstElement * element, GstStateChange transition)

 {

   GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;

   switch (transition) {

     case GST_STATE_CHANGE_READY_TO_PAUSED:

       break;

     default:

       break;

   }

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

   if (ret == GST_STATE_CHANGE_FAILURE)

     goto done;

   switch (transition) {

     case GST_STATE_CHANGE_PAUSED_TO_READY:

       gst_nuv_demux_destoy_src_pad (GST_NUV_DEMUX (element));

       gst_nuv_demux_reset (GST_NUV_DEMUX (element));

       break;

     default:

       break;

   }

 done:

   return ret;

 }

 static gboolean

 plugin_init (GstPlugin * plugin)

 {

 #ifdef ENABLE_NLS

   setlocale (LC_ALL, "");

   bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);

 #endif /* ENABLE_NLS */

   if (!gst_element_register (plugin, "nuvdemux", GST_RANK_SECONDARY,

           GST_TYPE_NUV_DEMUX)) {

     return FALSE;

   }

   return TRUE;

 }

 GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,

     GST_VERSION_MINOR,

     "nuvdemux",

     "Demuxes and muxes audio and video",

     plugin_init, VERSION, "LGPL", "NuvDemux", "")