summaryrefslogtreecommitdiff
path: root/ext/kate/gstkateutil.c
blob: cf1a2af4736315ca96afea8e7273f2c508545400 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
/* GStreamer
 * Copyright (C) 2008 Vincent Penquerc'h <ogg.k.ogg.k@googlemail.com>
 *
 * 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.
 */

/* FIXME: shouldn't all this GstKateDecoderBase stuff really be a base class? */

#ifdef HAVE_CONFIG_H
#  include "config.h"
#endif

#include <string.h>
#ifdef HAVE_TIGER
#include <tiger/tiger.h>
#endif
#include <gst/tag/tag.h>
#include "gstkate.h"
#include "gstkateutil.h"

GST_DEBUG_CATEGORY_EXTERN (gst_kateutil_debug);
#define GST_CAT_DEFAULT gst_kateutil_debug

static void gst_kate_util_decoder_base_free_event_queue (GstKateDecoderBase *
    decoder);

GstCaps *
gst_kate_util_set_header_on_caps (GstElement * element, GstCaps * caps,
    GList * headers)
{
  GstStructure *structure;
  GValue array = { 0 };

  GST_LOG_OBJECT (element, "caps: %" GST_PTR_FORMAT, caps);

  if (G_UNLIKELY (!caps))
    return NULL;
  if (G_UNLIKELY (!headers))
    return NULL;

  caps = gst_caps_make_writable (caps);
  structure = gst_caps_get_structure (caps, 0);

  g_value_init (&array, GST_TYPE_ARRAY);

  while (headers) {
    GValue value = { 0 };
    GstBuffer *buffer = headers->data;
    g_assert (buffer);
    g_value_init (&value, GST_TYPE_BUFFER);
    buffer = gst_buffer_copy (buffer);
    GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_HEADER);
    gst_value_take_buffer (&value, buffer);
    gst_value_array_append_value (&array, &value);
    g_value_unset (&value);
    headers = headers->next;
  }

  gst_structure_take_value (structure, "streamheader", &array);

  GST_LOG_OBJECT (element, "here are the newly set caps: %" GST_PTR_FORMAT,
      caps);

  return caps;
}

void
gst_kate_util_install_decoder_base_properties (GObjectClass * gobject_class)
{
  g_object_class_install_property (gobject_class, ARG_DEC_BASE_LANGUAGE,
      g_param_spec_string ("language", "Language", "The language of the stream",
          "", G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class, ARG_DEC_BASE_CATEGORY,
      g_param_spec_string ("category", "Category", "The category of the stream",
          "", G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class,
      ARG_DEC_BASE_ORIGINAL_CANVAS_WIDTH,
      g_param_spec_int ("original-canvas-width",
          "Original canvas width (0 is unspecified)",
          "The canvas width this stream was authored for", 0, G_MAXINT, 0,
          G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));

  g_object_class_install_property (gobject_class,
      ARG_DEC_BASE_ORIGINAL_CANVAS_HEIGHT,
      g_param_spec_int ("original-canvas-height", "Original canvas height",
          "The canvas height this stream was authored for (0 is unspecified)",
          0, G_MAXINT, 0, G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
}

void
gst_kate_util_decode_base_init (GstKateDecoderBase * decoder,
    gboolean delay_events)
{
  if (G_UNLIKELY (!decoder))
    return;

  decoder->language = NULL;
  decoder->category = NULL;
  decoder->original_canvas_width = 0;
  decoder->original_canvas_height = 0;
  decoder->tags = NULL;
  decoder->tags_changed = FALSE;
  decoder->initialized = FALSE;
  decoder->delay_events = delay_events;
  decoder->event_queue = NULL;
}

static void
gst_kate_util_decode_base_reset (GstKateDecoderBase * decoder)
{
  g_free (decoder->language);
  decoder->language = NULL;
  g_free (decoder->category);
  decoder->category = NULL;
  if (decoder->tags) {
    gst_tag_list_unref (decoder->tags);
    decoder->tags = NULL;
  }
  decoder->tags_changed = FALSE;
  decoder->original_canvas_width = 0;
  decoder->original_canvas_height = 0;
  if (decoder->event_queue) {
    gst_kate_util_decoder_base_free_event_queue (decoder);
  }
  decoder->initialized = FALSE;
}

gboolean
gst_kate_util_decoder_base_queue_event (GstKateDecoderBase * decoder,
    GstEvent * event, gboolean (*handler) (GstPad *, GstObject *, GstEvent *),
    GstObject * parent, GstPad * pad)
{
  gboolean can_be_queued;

  switch (GST_EVENT_TYPE (event)) {
    case GST_EVENT_FLUSH_START:
    case GST_EVENT_FLUSH_STOP:
    case GST_EVENT_EOS:
      can_be_queued = FALSE;
      break;
    case GST_EVENT_SEGMENT:
      gst_kate_util_decoder_base_segment_event (decoder, event);
      can_be_queued = TRUE;
      break;
    default:
      can_be_queued = TRUE;
      break;
  }

  if (GST_EVENT_IS_STICKY (event) && GST_EVENT_TYPE (event) < GST_EVENT_CAPS)
    can_be_queued = FALSE;

  if (decoder->delay_events && can_be_queued) {
    GstKateDecoderBaseQueuedEvent *item;
    GST_DEBUG_OBJECT (decoder, "We have to delay the event");
    item = g_slice_new (GstKateDecoderBaseQueuedEvent);
    if (item) {
      item->event = event;
      item->parent = parent;
      item->pad = pad;
      item->handler = handler;
      g_queue_push_tail (decoder->event_queue, item);
      return TRUE;
    } else {
      return FALSE;
    }
  } else {
    return FALSE;
  }
}

static void
gst_kate_util_decoder_base_free_event_queue (GstKateDecoderBase * decoder)
{
  while (decoder->event_queue->length) {
    GstKateDecoderBaseQueuedEvent *item = (GstKateDecoderBaseQueuedEvent *)
        g_queue_pop_head (decoder->event_queue);
    gst_event_unref (item->event);
    g_slice_free (GstKateDecoderBaseQueuedEvent, item);
  }
  g_queue_free (decoder->event_queue);
  decoder->event_queue = NULL;
}

static void
gst_kate_util_decoder_base_drain_event_queue (GstKateDecoderBase * decoder)
{
  decoder->delay_events = FALSE;

  if (decoder->event_queue->length == 0)
    return;

  GST_DEBUG_OBJECT (decoder, "We can now drain all events!");
  while (decoder->event_queue->length) {
    GstKateDecoderBaseQueuedEvent *item = (GstKateDecoderBaseQueuedEvent *)
        g_queue_pop_head (decoder->event_queue);
    (*item->handler) (item->pad, item->parent, item->event);
    g_slice_free (GstKateDecoderBaseQueuedEvent, item);
  }
}

void
gst_kate_util_decoder_base_add_tags (GstKateDecoderBase * decoder,
    GstTagList * tags, gboolean take_ownership_of_tags)
{
  if (!decoder->tags) {
    if (!take_ownership_of_tags)
      tags = gst_tag_list_ref (tags);
    decoder->tags = tags;
  } else {
    GstTagList *old = decoder->tags;
    decoder->tags = gst_tag_list_merge (old, tags, GST_TAG_MERGE_REPLACE);
    gst_tag_list_unref (old);
    if (take_ownership_of_tags)
      gst_tag_list_unref (tags);
  }
  decoder->tags_changed = TRUE;
}

GstEvent *
gst_kate_util_decoder_base_get_tag_event (GstKateDecoderBase * decoder)
{
  if (!decoder->tags)
    return NULL;
  decoder->tags_changed = FALSE;
  return gst_event_new_tag (gst_tag_list_ref (decoder->tags));
}

gboolean
gst_kate_util_decoder_base_get_property (GstKateDecoderBase * decoder,
    GObject * object, guint prop_id, GValue * value, GParamSpec * pspec)
{
  gboolean res = TRUE;
  switch (prop_id) {
    case ARG_DEC_BASE_LANGUAGE:
      g_value_set_string (value, decoder->language);
      break;
    case ARG_DEC_BASE_CATEGORY:
      g_value_set_string (value, decoder->category);
      break;
    case ARG_DEC_BASE_ORIGINAL_CANVAS_WIDTH:
      g_value_set_int (value, decoder->original_canvas_width);
      break;
    case ARG_DEC_BASE_ORIGINAL_CANVAS_HEIGHT:
      g_value_set_int (value, decoder->original_canvas_height);
      break;
    default:
      res = FALSE;
      break;
  }
  return res;
}

static inline gboolean
gst_kate_util_is_utf8_string (const char *value, size_t len)
{
  if (len == 0)
    return FALSE;
  if (memchr (value, 0, len - 1))
    return FALSE;
  if (value[len - 1])
    return FALSE;
  return (kate_text_validate (kate_utf8, value, len) >= 0);
}

GstFlowReturn
gst_kate_util_decoder_base_chain_kate_packet (GstKateDecoderBase * decoder,
    GstElement * element, GstPad * pad, GstBuffer * buf, GstPad * srcpad,
    GstPad * tagpad, GstCaps ** src_caps, const kate_event ** ev)
{
  kate_packet kp;
  int ret;
  GstFlowReturn rflow = GST_FLOW_OK;
  gboolean is_header;
  GstMapInfo info;
  gsize header_size;
  guint8 header[1];

  header_size = gst_buffer_extract (buf, 0, header, 1);

  GST_DEBUG_OBJECT (element,
      "got kate packet, %" G_GSIZE_FORMAT " bytes, type %02x",
      gst_buffer_get_size (buf), header_size == 0 ? -1 : header[0]);

  is_header = header_size > 0 && (header[0] & 0x80);

  if (!is_header && decoder->tags_changed) {
    /* after we've processed headers, send any tags before processing the data packet */
    GST_DEBUG_OBJECT (element, "Not a header, sending tags for pad %s:%s",
        GST_DEBUG_PAD_NAME (tagpad));
    gst_pad_push_event (tagpad,
        gst_kate_util_decoder_base_get_tag_event (decoder));
  }

  if (gst_buffer_map (buf, &info, GST_MAP_READ)) {
    kate_packet_wrap (&kp, info.size, info.data);
    ret = kate_high_decode_packetin (&decoder->k, &kp, ev);
    gst_buffer_unmap (buf, &info);
  } else {
    GST_ELEMENT_ERROR (element, STREAM, DECODE, (NULL),
        ("Failed to map buffer"));
    return GST_FLOW_ERROR;
  }

  if (G_UNLIKELY (ret < 0)) {
    GST_ELEMENT_ERROR (element, STREAM, DECODE, (NULL),
        ("Failed to decode Kate packet: %s",
            gst_kate_util_get_error_message (ret)));
    return GST_FLOW_ERROR;
  }

  if (G_UNLIKELY (ret > 0)) {
    GST_DEBUG_OBJECT (element,
        "kate_high_decode_packetin has received EOS packet");
  }

  /* headers may be interesting to retrieve information from */
  if (G_UNLIKELY (is_header)) {
    switch (header[0]) {
      case 0x80:               /* ID header */
        GST_INFO_OBJECT (element, "Parsed ID header: language %s, category %s",
            decoder->k.ki->language, decoder->k.ki->category);
        if (src_caps) {
          if (*src_caps) {
            gst_caps_unref (*src_caps);
            *src_caps = NULL;
          }
          if (strcmp (decoder->k.ki->category, "K-SPU") == 0 ||
              strcmp (decoder->k.ki->category, "spu-subtitles") == 0) {
            *src_caps = gst_caps_new_empty_simple ("subpicture/x-dvd");
          } else if (decoder->k.ki->text_markup_type == kate_markup_none) {
            *src_caps = gst_caps_new_simple ("text/x-raw", "format",
                G_TYPE_STRING, "utf8", NULL);
          } else {
            *src_caps = gst_caps_new_simple ("text/x-raw", "format",
                G_TYPE_STRING, "pango-markup", NULL);
          }
          GST_INFO_OBJECT (srcpad, "Setting caps: %" GST_PTR_FORMAT, *src_caps);
          if (!gst_pad_set_caps (srcpad, *src_caps)) {
            GST_ERROR_OBJECT (srcpad, "Failed to set caps %" GST_PTR_FORMAT,
                *src_caps);
          }
        }
        if (decoder->k.ki->language && *decoder->k.ki->language) {
          GstTagList *tags = gst_tag_list_new_empty ();
          gchar *lang_code;

          /* en_GB -> en */
          lang_code = g_ascii_strdown (decoder->k.ki->language, -1);
          g_strdelimit (lang_code, NULL, '\0');
          gst_tag_list_add (tags, GST_TAG_MERGE_APPEND, GST_TAG_LANGUAGE_CODE,
              lang_code, NULL);
          g_free (lang_code);
          /* TODO: category - where should it go ? */
          gst_kate_util_decoder_base_add_tags (decoder, tags, TRUE);
        }

        /* update properties */
        g_free (decoder->language);
        decoder->language = g_strdup (decoder->k.ki->language);
        g_free (decoder->category);
        decoder->category = g_strdup (decoder->k.ki->category);
        decoder->original_canvas_width = decoder->k.ki->original_canvas_width;
        decoder->original_canvas_height = decoder->k.ki->original_canvas_height;

        /* we can now send away any event we've delayed, as the src pad now has caps */
        gst_kate_util_decoder_base_drain_event_queue (decoder);

        break;

      case 0x81:               /* Vorbis comments header */
        GST_INFO_OBJECT (element, "Parsed comments header");
        {
          gchar *encoder = NULL;
          GstTagList *list = gst_tag_list_from_vorbiscomment_buffer (buf,
              (const guint8 *) "\201kate\0\0\0\0", 9, &encoder);
          if (!list) {
            GST_ERROR_OBJECT (element, "failed to decode comment header");
            list = gst_tag_list_new_empty ();
          }
          if (encoder) {
            gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
                GST_TAG_ENCODER, encoder, NULL);
            g_free (encoder);
          }
          gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
              GST_TAG_SUBTITLE_CODEC, "Kate", NULL);
          gst_tag_list_add (list, GST_TAG_MERGE_REPLACE,
              GST_TAG_ENCODER_VERSION, decoder->k.ki->bitstream_version_major,
              NULL);

          gst_kate_util_decoder_base_add_tags (decoder, list, TRUE);

          if (decoder->initialized) {
            gst_pad_push_event (tagpad,
                gst_event_new_tag (gst_tag_list_ref (decoder->tags)));
          }
        }
        break;

      default:
        break;
    }
  }
#if ((KATE_VERSION_MAJOR<<16)|(KATE_VERSION_MINOR<<8)|KATE_VERSION_PATCH) >= 0x000400
  else if (*ev && (*ev)->meta) {
    int count = kate_meta_query_count ((*ev)->meta);
    if (count > 0) {
      GstTagList *evtags = gst_tag_list_new_empty ();
      int idx;
      GST_DEBUG_OBJECT (decoder, "Kate event has %d attached metadata", count);
      for (idx = 0; idx < count; ++idx) {
        const char *tag, *value;
        size_t len;
        if (kate_meta_query ((*ev)->meta, idx, &tag, &value, &len) < 0) {
          GST_WARNING_OBJECT (decoder, "Failed to retrieve metadata %d", idx);
        } else {
          if (gst_kate_util_is_utf8_string (value, len)) {
            gchar *compound = g_strdup_printf ("%s=%s", tag, value);
            GST_DEBUG_OBJECT (decoder,
                "Metadata %d: %s=%s (%" G_GSIZE_FORMAT " bytes)", idx, tag,
                value, len);
            gst_tag_list_add (evtags, GST_TAG_MERGE_APPEND,
                GST_TAG_EXTENDED_COMMENT, compound, NULL);
            g_free (compound);
          } else {
            GST_INFO_OBJECT (decoder,
                "Metadata %d, (%s, %" G_GSIZE_FORMAT
                " bytes) is binary, ignored", idx, tag, len);
          }
        }
      }
      gst_kate_util_decoder_base_add_tags (decoder, evtags, TRUE);
      gst_pad_push_event (tagpad,
          gst_kate_util_decoder_base_get_tag_event (decoder));
    }
  }
#endif

  return rflow;
}

GstStateChangeReturn
gst_kate_decoder_base_change_state (GstKateDecoderBase * decoder,
    GstElement * element, GstElementClass * parent_class,
    GstStateChange transition)
{
  GstStateChangeReturn res;
  int ret;

  switch (transition) {
    case GST_STATE_CHANGE_NULL_TO_READY:
      break;
    case GST_STATE_CHANGE_READY_TO_PAUSED:
      GST_DEBUG_OBJECT (element, "READY -> PAUSED, initializing kate state");
      ret = kate_high_decode_init (&decoder->k);
      if (ret < 0) {
        GST_WARNING_OBJECT (element, "failed to initialize kate state: %s",
            gst_kate_util_get_error_message (ret));
      }
      gst_segment_init (&decoder->kate_segment, GST_FORMAT_UNDEFINED);
      decoder->kate_flushing = FALSE;
      decoder->initialized = TRUE;
      decoder->event_queue = g_queue_new ();
      break;
    case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
      break;
    default:
      break;
  }

  res = parent_class->change_state (element, transition);

  switch (transition) {
    case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
      break;
    case GST_STATE_CHANGE_PAUSED_TO_READY:
      GST_DEBUG_OBJECT (element, "PAUSED -> READY, clearing kate state");
      if (decoder->initialized) {
        kate_high_decode_clear (&decoder->k);
        decoder->initialized = FALSE;
      }
      gst_segment_init (&decoder->kate_segment, GST_FORMAT_UNDEFINED);
      decoder->kate_flushing = TRUE;
      gst_kate_util_decode_base_reset (decoder);
      break;
    case GST_STATE_CHANGE_READY_TO_NULL:
      gst_kate_util_decode_base_reset (decoder);
      break;
    default:
      break;
  }

  return res;
}

void
gst_kate_util_decoder_base_set_flushing (GstKateDecoderBase * decoder,
    gboolean flushing)
{
  decoder->kate_flushing = flushing;
  gst_segment_init (&decoder->kate_segment, GST_FORMAT_UNDEFINED);
}

void
gst_kate_util_decoder_base_segment_event (GstKateDecoderBase * decoder,
    GstEvent * event)
{
  GstSegment seg;

  gst_event_copy_segment (event, &seg);

  GST_DEBUG_OBJECT (decoder, "kate pad segment: %" GST_SEGMENT_FORMAT, &seg);

  decoder->kate_segment = seg;
}

gboolean
gst_kate_util_decoder_base_update_segment (GstKateDecoderBase * decoder,
    GstElement * element, GstBuffer * buf)
{
  guint64 clip_start = 0, clip_stop = 0;
  gboolean in_seg;

  if (decoder->kate_flushing) {
    GST_LOG_OBJECT (element, "Kate pad flushing, buffer ignored");
    return FALSE;
  }

  if (G_LIKELY (GST_BUFFER_TIMESTAMP_IS_VALID (buf))) {
    GstClockTime stop;

    if (G_LIKELY (GST_BUFFER_DURATION_IS_VALID (buf)))
      stop = GST_BUFFER_TIMESTAMP (buf) + GST_BUFFER_DURATION (buf);
    else
      stop = GST_CLOCK_TIME_NONE;

    in_seg = gst_segment_clip (&decoder->kate_segment, GST_FORMAT_TIME,
        GST_BUFFER_TIMESTAMP (buf), stop, &clip_start, &clip_stop);
  } else {
    in_seg = TRUE;
  }

  if (in_seg) {
    if (GST_BUFFER_TIMESTAMP_IS_VALID (buf)) {
      decoder->kate_segment.position = clip_start;
    }
  } else {
    GST_INFO_OBJECT (element, "Kate buffer not in segment, ignored");
  }

  return in_seg;
}

static GstClockTime
gst_kate_util_granule_time (kate_state * k, gint64 granulepos)
{
  if (G_UNLIKELY (granulepos == -1))
    return -1;

  return kate_granule_time (k->ki, granulepos) * GST_SECOND;
}

/*
conversions on the sink:
  - default is granules at num/den rate (subject to the granule shift)
  - default -> time is possible
  - bytes do not mean anything, packets can be any number of bytes, and we
    have no way to know the number of bytes emitted without decoding
conversions on the source:
  - nothing
*/

gboolean
gst_kate_decoder_base_convert (GstKateDecoderBase * decoder,
    GstElement * element, GstPad * pad, GstFormat src_fmt, gint64 src_val,
    GstFormat * dest_fmt, gint64 * dest_val)
{
  gboolean res = FALSE;

  if (src_fmt == *dest_fmt) {
    *dest_val = src_val;
    return TRUE;
  }

  if (!decoder->initialized) {
    GST_WARNING_OBJECT (element, "not initialized yet");
    return FALSE;
  }

  if (src_fmt == GST_FORMAT_BYTES || *dest_fmt == GST_FORMAT_BYTES) {
    GST_WARNING_OBJECT (element, "unsupported format");
    return FALSE;
  }

  switch (src_fmt) {
    case GST_FORMAT_DEFAULT:
      switch (*dest_fmt) {
        case GST_FORMAT_TIME:
          *dest_val = gst_kate_util_granule_time (&decoder->k, src_val);
          res = TRUE;
          break;
        default:
          res = FALSE;
          break;
      }
      break;
    default:
      res = FALSE;
      break;
  }

  if (!res) {
    GST_WARNING_OBJECT (element, "unsupported format");
  }

  return res;
}

gboolean
gst_kate_decoder_base_sink_query (GstKateDecoderBase * decoder,
    GstElement * element, GstPad * pad, GstObject * parent, GstQuery * query)
{
  switch (GST_QUERY_TYPE (query)) {
    case GST_QUERY_CONVERT:
    {
      GstFormat src_fmt, dest_fmt;
      gint64 src_val, dest_val;

      gst_query_parse_convert (query, &src_fmt, &src_val, &dest_fmt, &dest_val);
      if (!gst_kate_decoder_base_convert (decoder, element, pad, src_fmt,
              src_val, &dest_fmt, &dest_val)) {
        return gst_pad_query_default (pad, parent, query);
      }
      gst_query_set_convert (query, src_fmt, src_val, dest_fmt, dest_val);
      return TRUE;
    }
    default:
      return gst_pad_query_default (pad, parent, query);
  }
}

const char *
gst_kate_util_get_error_message (int ret)
{
  switch (ret) {
    case KATE_E_NOT_FOUND:
      return "value not found";
    case KATE_E_INVALID_PARAMETER:
      return "invalid parameter";
    case KATE_E_OUT_OF_MEMORY:
      return "out of memory";
    case KATE_E_BAD_GRANULE:
      return "bad granule";
    case KATE_E_INIT:
      return "initialization error";
    case KATE_E_BAD_PACKET:
      return "bad packet";
    case KATE_E_TEXT:
      return "invalid/truncated text";
    case KATE_E_LIMIT:
      return "a limit was exceeded";
    case KATE_E_VERSION:
      return "unsupported bitstream version";
    case KATE_E_NOT_KATE:
      return "not a kate bitstream";
    case KATE_E_BAD_TAG:
      return "bad tag";
    case KATE_E_IMPL:
      return "not implemented";

#ifdef HAVE_TIGER
    case TIGER_E_NOT_FOUND:
      return "value not found";
    case TIGER_E_INVALID_PARAMETER:
      return "invalid parameter";
    case TIGER_E_OUT_OF_MEMORY:
      return "out of memory";
    case TIGER_E_CAIRO_ERROR:
      return "Cairo error";
    case TIGER_E_BAD_SURFACE_TYPE:
      return "bad surface type";
#endif

    default:
      return "unknown error";
  }
}