1 /*
2  * Copyright (C) 2014 Collabora Ltd.
3  *     Author: Nicolas Dufresne <nicolas.dufresne@collabora.com>
4  *
5  * This library is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU Library General Public
7  * License as published by the Free Software Foundation; either
8  * version 2 of the License, or (at your option) any later version.
9  *
10  * This library is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * Library General Public License for more details.
14  *
15  * You should have received a copy of the GNU Library General Public
16  * License along with this library; if not, write to the
17  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18  * Boston, MA 02110-1301, USA.
19  *
20  */
21 
22 #ifdef HAVE_CONFIG_H
23 #include "config.h"
24 #endif
25 
26 #include <sys/stat.h>
27 #include <fcntl.h>
28 #include <errno.h>
29 #include <unistd.h>
30 #include <string.h>
31 
32 #include "gstv4l2object.h"
33 #include "gstv4l2videodec.h"
34 
35 #include <string.h>
36 #include <gst/gst-i18n-plugin.h>
37 
38 GST_DEBUG_CATEGORY_STATIC (gst_v4l2_video_dec_debug);
39 #define GST_CAT_DEFAULT gst_v4l2_video_dec_debug
40 
41 typedef struct
42 {
43   gchar *device;
44   GstCaps *sink_caps;
45   GstCaps *src_caps;
46   const gchar *longname;
47   const gchar *description;
48 } GstV4l2VideoDecCData;
49 
50 enum
51 {
52   PROP_0,
53   V4L2_STD_OBJECT_PROPS
54 };
55 
56 #define gst_v4l2_video_dec_parent_class parent_class
57 G_DEFINE_ABSTRACT_TYPE (GstV4l2VideoDec, gst_v4l2_video_dec,
58     GST_TYPE_VIDEO_DECODER);
59 
60 static GstFlowReturn gst_v4l2_video_dec_finish (GstVideoDecoder * decoder);
61 
62 static void
gst_v4l2_video_dec_set_property(GObject * object,guint prop_id,const GValue * value,GParamSpec * pspec)63 gst_v4l2_video_dec_set_property (GObject * object,
64     guint prop_id, const GValue * value, GParamSpec * pspec)
65 {
66   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (object);
67 
68   switch (prop_id) {
69     case PROP_CAPTURE_IO_MODE:
70       if (!gst_v4l2_object_set_property_helper (self->v4l2capture,
71               prop_id, value, pspec)) {
72         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
73       }
74       break;
75 
76       /* By default, only set on output */
77     default:
78       if (!gst_v4l2_object_set_property_helper (self->v4l2output,
79               prop_id, value, pspec)) {
80         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
81       }
82       break;
83   }
84 }
85 
86 static void
gst_v4l2_video_dec_get_property(GObject * object,guint prop_id,GValue * value,GParamSpec * pspec)87 gst_v4l2_video_dec_get_property (GObject * object,
88     guint prop_id, GValue * value, GParamSpec * pspec)
89 {
90   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (object);
91 
92   switch (prop_id) {
93     case PROP_CAPTURE_IO_MODE:
94       if (!gst_v4l2_object_get_property_helper (self->v4l2capture,
95               prop_id, value, pspec)) {
96         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
97       }
98       break;
99 
100       /* By default read from output */
101     default:
102       if (!gst_v4l2_object_get_property_helper (self->v4l2output,
103               prop_id, value, pspec)) {
104         G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
105       }
106       break;
107   }
108 }
109 
110 static gboolean
gst_v4l2_video_dec_open(GstVideoDecoder * decoder)111 gst_v4l2_video_dec_open (GstVideoDecoder * decoder)
112 {
113   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
114   GstCaps *codec_caps;
115 
116   GST_DEBUG_OBJECT (self, "Opening");
117 
118   if (!gst_v4l2_object_open (self->v4l2output))
119     goto failure;
120 
121   if (!gst_v4l2_object_open_shared (self->v4l2capture, self->v4l2output))
122     goto failure;
123 
124   codec_caps = gst_pad_get_pad_template_caps (decoder->sinkpad);
125   self->probed_sinkcaps = gst_v4l2_object_probe_caps (self->v4l2output,
126       codec_caps);
127   gst_caps_unref (codec_caps);
128 
129   if (gst_caps_is_empty (self->probed_sinkcaps))
130     goto no_encoded_format;
131 
132   return TRUE;
133 
134 no_encoded_format:
135   GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS,
136       (_("Decoder on device %s has no supported input format"),
137           self->v4l2output->videodev), (NULL));
138   goto failure;
139 
140 failure:
141   if (GST_V4L2_IS_OPEN (self->v4l2output))
142     gst_v4l2_object_close (self->v4l2output);
143 
144   if (GST_V4L2_IS_OPEN (self->v4l2capture))
145     gst_v4l2_object_close (self->v4l2capture);
146 
147   gst_caps_replace (&self->probed_srccaps, NULL);
148   gst_caps_replace (&self->probed_sinkcaps, NULL);
149 
150   return FALSE;
151 }
152 
153 static gboolean
gst_v4l2_video_dec_close(GstVideoDecoder * decoder)154 gst_v4l2_video_dec_close (GstVideoDecoder * decoder)
155 {
156   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
157 
158   GST_DEBUG_OBJECT (self, "Closing");
159 
160   gst_v4l2_object_close (self->v4l2output);
161   gst_v4l2_object_close (self->v4l2capture);
162   gst_caps_replace (&self->probed_srccaps, NULL);
163   gst_caps_replace (&self->probed_sinkcaps, NULL);
164 
165   return TRUE;
166 }
167 
168 static gboolean
gst_v4l2_video_dec_start(GstVideoDecoder * decoder)169 gst_v4l2_video_dec_start (GstVideoDecoder * decoder)
170 {
171   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
172 
173   GST_DEBUG_OBJECT (self, "Starting");
174 
175   gst_v4l2_object_unlock (self->v4l2output);
176   g_atomic_int_set (&self->active, TRUE);
177   self->output_flow = GST_FLOW_OK;
178 
179   return TRUE;
180 }
181 
182 static gboolean
gst_v4l2_video_dec_stop(GstVideoDecoder * decoder)183 gst_v4l2_video_dec_stop (GstVideoDecoder * decoder)
184 {
185   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
186 
187   GST_DEBUG_OBJECT (self, "Stopping");
188 
189   gst_v4l2_object_unlock (self->v4l2output);
190   gst_v4l2_object_unlock (self->v4l2capture);
191 
192   /* Wait for capture thread to stop */
193   gst_pad_stop_task (decoder->srcpad);
194 
195   GST_VIDEO_DECODER_STREAM_LOCK (decoder);
196   self->output_flow = GST_FLOW_OK;
197   GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
198 
199   /* Should have been flushed already */
200   g_assert (g_atomic_int_get (&self->active) == FALSE);
201 
202   gst_v4l2_object_stop (self->v4l2output);
203   gst_v4l2_object_stop (self->v4l2capture);
204 
205   if (self->input_state) {
206     gst_video_codec_state_unref (self->input_state);
207     self->input_state = NULL;
208   }
209 
210   GST_DEBUG_OBJECT (self, "Stopped");
211 
212   return TRUE;
213 }
214 
215 static gboolean
gst_v4l2_video_dec_set_format(GstVideoDecoder * decoder,GstVideoCodecState * state)216 gst_v4l2_video_dec_set_format (GstVideoDecoder * decoder,
217     GstVideoCodecState * state)
218 {
219   GstV4l2Error error = GST_V4L2_ERROR_INIT;
220   gboolean ret = TRUE;
221   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
222 
223   GST_DEBUG_OBJECT (self, "Setting format: %" GST_PTR_FORMAT, state->caps);
224 
225   if (self->input_state) {
226     if (gst_v4l2_object_caps_equal (self->v4l2output, state->caps)) {
227       GST_DEBUG_OBJECT (self, "Compatible caps");
228       goto done;
229     }
230     gst_video_codec_state_unref (self->input_state);
231     self->input_state = NULL;
232 
233     gst_v4l2_video_dec_finish (decoder);
234     gst_v4l2_object_stop (self->v4l2output);
235 
236     /* The renegotiation flow don't blend with the base class flow. To properly
237      * stop the capture pool, if the buffers can't be orphaned, we need to
238      * reclaim our buffers, which will happend through the allocation query.
239      * The allocation query is triggered by gst_video_decoder_negotiate() which
240      * requires the output caps to be set, but we can't know this information
241      * as we rely on the decoder, which requires the capture queue to be
242      * stopped.
243      *
244      * To workaround this issue, we simply run an allocation query with the
245      * old negotiated caps in order to drain/reclaim our buffers. That breaks
246      * the complexity and should not have much impact in performance since the
247      * following allocation query will happen on a drained pipeline and won't
248      * block. */
249     if (self->v4l2capture->pool &&
250         !gst_v4l2_buffer_pool_orphan (&self->v4l2capture->pool)) {
251       GstCaps *caps = gst_pad_get_current_caps (decoder->srcpad);
252       if (caps) {
253         GstQuery *query = gst_query_new_allocation (caps, FALSE);
254         gst_pad_peer_query (decoder->srcpad, query);
255         gst_query_unref (query);
256         gst_caps_unref (caps);
257       }
258     }
259 
260     gst_v4l2_object_stop (self->v4l2capture);
261     self->output_flow = GST_FLOW_OK;
262   }
263 
264   ret = gst_v4l2_object_set_format (self->v4l2output, state->caps, &error);
265 
266   gst_caps_replace (&self->probed_srccaps, NULL);
267   self->probed_srccaps = gst_v4l2_object_probe_caps (self->v4l2capture,
268       gst_v4l2_object_get_raw_caps ());
269 
270   if (gst_caps_is_empty (self->probed_srccaps))
271     goto no_raw_format;
272 
273   if (ret)
274     self->input_state = gst_video_codec_state_ref (state);
275   else
276     gst_v4l2_error (self, &error);
277 
278 done:
279   return ret;
280 
281 no_raw_format:
282   GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS,
283       (_("Decoder on device %s has no supported output format"),
284           self->v4l2output->videodev), (NULL));
285   return GST_FLOW_ERROR;
286 }
287 
288 static gboolean
gst_v4l2_video_dec_flush(GstVideoDecoder * decoder)289 gst_v4l2_video_dec_flush (GstVideoDecoder * decoder)
290 {
291   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
292 
293   GST_DEBUG_OBJECT (self, "Flushed");
294 
295   /* Ensure the processing thread has stopped for the reverse playback
296    * discount case */
297   if (gst_pad_get_task_state (decoder->srcpad) == GST_TASK_STARTED) {
298     GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
299 
300     gst_v4l2_object_unlock (self->v4l2output);
301     gst_v4l2_object_unlock (self->v4l2capture);
302     gst_pad_stop_task (decoder->srcpad);
303     GST_VIDEO_DECODER_STREAM_LOCK (decoder);
304   }
305 
306   self->output_flow = GST_FLOW_OK;
307 
308   gst_v4l2_object_unlock_stop (self->v4l2output);
309   gst_v4l2_object_unlock_stop (self->v4l2capture);
310 
311   if (self->v4l2output->pool)
312     gst_v4l2_buffer_pool_flush (self->v4l2output->pool);
313 
314   /* gst_v4l2_buffer_pool_flush() calls streamon the capture pool and must be
315    * called after gst_v4l2_object_unlock_stop() stopped flushing the buffer
316    * pool. */
317   if (self->v4l2capture->pool)
318     gst_v4l2_buffer_pool_flush (self->v4l2capture->pool);
319 
320   return TRUE;
321 }
322 
323 static gboolean
gst_v4l2_video_dec_negotiate(GstVideoDecoder * decoder)324 gst_v4l2_video_dec_negotiate (GstVideoDecoder * decoder)
325 {
326   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
327 
328   /* We don't allow renegotiation without carefull disabling the pool */
329   if (self->v4l2capture->pool &&
330       gst_buffer_pool_is_active (GST_BUFFER_POOL (self->v4l2capture->pool)))
331     return TRUE;
332 
333   return GST_VIDEO_DECODER_CLASS (parent_class)->negotiate (decoder);
334 }
335 
336 static gboolean
gst_v4l2_decoder_cmd(GstV4l2Object * v4l2object,guint cmd,guint flags)337 gst_v4l2_decoder_cmd (GstV4l2Object * v4l2object, guint cmd, guint flags)
338 {
339   struct v4l2_decoder_cmd dcmd = { 0, };
340 
341   GST_DEBUG_OBJECT (v4l2object->element,
342       "sending v4l2 decoder command %u with flags %u", cmd, flags);
343 
344   if (!GST_V4L2_IS_OPEN (v4l2object))
345     return FALSE;
346 
347   dcmd.cmd = cmd;
348   dcmd.flags = flags;
349   if (v4l2object->ioctl (v4l2object->video_fd, VIDIOC_DECODER_CMD, &dcmd) < 0)
350     goto dcmd_failed;
351 
352   return TRUE;
353 
354 dcmd_failed:
355   if (errno == ENOTTY) {
356     GST_INFO_OBJECT (v4l2object->element,
357         "Failed to send decoder command %u with flags %u for '%s'. (%s)",
358         cmd, flags, v4l2object->videodev, g_strerror (errno));
359   } else {
360     GST_ERROR_OBJECT (v4l2object->element,
361         "Failed to send decoder command %u with flags %u for '%s'. (%s)",
362         cmd, flags, v4l2object->videodev, g_strerror (errno));
363   }
364   return FALSE;
365 }
366 
367 static GstFlowReturn
gst_v4l2_video_dec_finish(GstVideoDecoder * decoder)368 gst_v4l2_video_dec_finish (GstVideoDecoder * decoder)
369 {
370   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
371   GstFlowReturn ret = GST_FLOW_OK;
372   GstBuffer *buffer;
373 
374   if (gst_pad_get_task_state (decoder->srcpad) != GST_TASK_STARTED)
375     goto done;
376 
377   GST_DEBUG_OBJECT (self, "Finishing decoding");
378 
379   GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
380 
381   if (gst_v4l2_decoder_cmd (self->v4l2output, V4L2_DEC_CMD_STOP, 0)) {
382     GstTask *task = decoder->srcpad->task;
383 
384     /* If the decoder stop command succeeded, just wait until processing is
385      * finished */
386     GST_DEBUG_OBJECT (self, "Waiting for decoder stop");
387     GST_OBJECT_LOCK (task);
388     while (GST_TASK_STATE (task) == GST_TASK_STARTED)
389       GST_TASK_WAIT (task);
390     GST_OBJECT_UNLOCK (task);
391     ret = GST_FLOW_FLUSHING;
392   } else {
393     /* otherwise keep queuing empty buffers until the processing thread has
394      * stopped, _pool_process() will return FLUSHING when that happened */
395     while (ret == GST_FLOW_OK) {
396       buffer = gst_buffer_new ();
397       ret =
398           gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->
399               v4l2output->pool), &buffer);
400       gst_buffer_unref (buffer);
401     }
402   }
403 
404   /* and ensure the processing thread has stopped in case another error
405    * occured. */
406   gst_v4l2_object_unlock (self->v4l2capture);
407   gst_pad_stop_task (decoder->srcpad);
408   GST_VIDEO_DECODER_STREAM_LOCK (decoder);
409 
410   if (ret == GST_FLOW_FLUSHING)
411     ret = self->output_flow;
412 
413   GST_DEBUG_OBJECT (decoder, "Done draining buffers");
414 
415   /* TODO Shall we cleanup any reffed frame to workaround broken decoders ? */
416 
417 done:
418   return ret;
419 }
420 
421 static GstFlowReturn
gst_v4l2_video_dec_drain(GstVideoDecoder * decoder)422 gst_v4l2_video_dec_drain (GstVideoDecoder * decoder)
423 {
424   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
425 
426   GST_DEBUG_OBJECT (self, "Draining...");
427   gst_v4l2_video_dec_finish (decoder);
428   gst_v4l2_video_dec_flush (decoder);
429 
430   return GST_FLOW_OK;
431 }
432 
433 static GstVideoCodecFrame *
gst_v4l2_video_dec_get_oldest_frame(GstVideoDecoder * decoder)434 gst_v4l2_video_dec_get_oldest_frame (GstVideoDecoder * decoder)
435 {
436   GstVideoCodecFrame *frame = NULL;
437   GList *frames, *l;
438   gint count = 0;
439 
440   frames = gst_video_decoder_get_frames (decoder);
441 
442   for (l = frames; l != NULL; l = l->next) {
443     GstVideoCodecFrame *f = l->data;
444 
445     if (!frame || frame->pts > f->pts)
446       frame = f;
447 
448     count++;
449   }
450 
451   if (frame) {
452     GST_LOG_OBJECT (decoder,
453         "Oldest frame is %d %" GST_TIME_FORMAT " and %d frames left",
454         frame->system_frame_number, GST_TIME_ARGS (frame->pts), count - 1);
455     gst_video_codec_frame_ref (frame);
456   }
457 
458   g_list_free_full (frames, (GDestroyNotify) gst_video_codec_frame_unref);
459 
460   return frame;
461 }
462 
463 static void
gst_v4l2_video_dec_loop(GstVideoDecoder * decoder)464 gst_v4l2_video_dec_loop (GstVideoDecoder * decoder)
465 {
466   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
467   GstV4l2BufferPool *v4l2_pool = GST_V4L2_BUFFER_POOL (self->v4l2capture->pool);
468   GstBufferPool *pool;
469   GstVideoCodecFrame *frame;
470   GstBuffer *buffer = NULL;
471   GstFlowReturn ret;
472 
473   GST_LOG_OBJECT (decoder, "Allocate output buffer");
474 
475   self->output_flow = GST_FLOW_OK;
476   do {
477     /* We cannot use the base class allotate helper since it taking the internal
478      * stream lock. we know that the acquire may need to poll until more frames
479      * comes in and holding this lock would prevent that.
480      */
481     pool = gst_video_decoder_get_buffer_pool (decoder);
482 
483     /* Pool may be NULL if we started going to READY state */
484     if (pool == NULL) {
485       ret = GST_FLOW_FLUSHING;
486       goto beach;
487     }
488 
489     ret = gst_buffer_pool_acquire_buffer (pool, &buffer, NULL);
490     g_object_unref (pool);
491 
492     if (ret != GST_FLOW_OK)
493       goto beach;
494 
495     GST_LOG_OBJECT (decoder, "Process output buffer");
496     ret = gst_v4l2_buffer_pool_process (v4l2_pool, &buffer);
497 
498   } while (ret == GST_V4L2_FLOW_CORRUPTED_BUFFER);
499 
500   if (ret != GST_FLOW_OK)
501     goto beach;
502 
503   frame = gst_v4l2_video_dec_get_oldest_frame (decoder);
504 
505   if (frame) {
506     frame->output_buffer = buffer;
507     buffer = NULL;
508     ret = gst_video_decoder_finish_frame (decoder, frame);
509 
510     if (ret != GST_FLOW_OK)
511       goto beach;
512   } else {
513     GST_WARNING_OBJECT (decoder, "Decoder is producing too many buffers");
514     gst_buffer_unref (buffer);
515   }
516 
517   return;
518 
519 beach:
520   GST_DEBUG_OBJECT (decoder, "Leaving output thread: %s",
521       gst_flow_get_name (ret));
522 
523   gst_buffer_replace (&buffer, NULL);
524   self->output_flow = ret;
525   gst_v4l2_object_unlock (self->v4l2output);
526   gst_pad_pause_task (decoder->srcpad);
527 }
528 
529 static gboolean
gst_v4l2_video_remove_padding(GstCapsFeatures * features,GstStructure * structure,gpointer user_data)530 gst_v4l2_video_remove_padding (GstCapsFeatures * features,
531     GstStructure * structure, gpointer user_data)
532 {
533   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (user_data);
534   GstVideoAlignment *align = &self->v4l2capture->align;
535   GstVideoInfo *info = &self->v4l2capture->info;
536   int width, height;
537 
538   if (!gst_structure_get_int (structure, "width", &width))
539     return TRUE;
540 
541   if (!gst_structure_get_int (structure, "height", &height))
542     return TRUE;
543 
544   if (align->padding_left != 0 || align->padding_top != 0 ||
545       height != info->height + align->padding_bottom)
546     return TRUE;
547 
548   if (height == info->height + align->padding_bottom) {
549     /* Some drivers may round up width to the padded with */
550     if (width == info->width + align->padding_right)
551       gst_structure_set (structure,
552           "width", G_TYPE_INT, width - align->padding_right,
553           "height", G_TYPE_INT, height - align->padding_bottom, NULL);
554     /* Some drivers may keep visible width and only round up bytesperline */
555     else if (width == info->width)
556       gst_structure_set (structure,
557           "height", G_TYPE_INT, height - align->padding_bottom, NULL);
558   }
559 
560   return TRUE;
561 }
562 
563 static GstFlowReturn
gst_v4l2_video_dec_handle_frame(GstVideoDecoder * decoder,GstVideoCodecFrame * frame)564 gst_v4l2_video_dec_handle_frame (GstVideoDecoder * decoder,
565     GstVideoCodecFrame * frame)
566 {
567   GstV4l2Error error = GST_V4L2_ERROR_INIT;
568   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
569   GstFlowReturn ret = GST_FLOW_OK;
570   gboolean processed = FALSE;
571   GstBuffer *tmp;
572   GstTaskState task_state;
573 
574   GST_DEBUG_OBJECT (self, "Handling frame %d", frame->system_frame_number);
575 
576   if (G_UNLIKELY (!g_atomic_int_get (&self->active)))
577     goto flushing;
578 
579   if (G_UNLIKELY (!GST_V4L2_IS_ACTIVE (self->v4l2output))) {
580     if (!self->input_state)
581       goto not_negotiated;
582     if (!gst_v4l2_object_set_format (self->v4l2output, self->input_state->caps,
583             &error))
584       goto not_negotiated;
585   }
586 
587   if (G_UNLIKELY (!GST_V4L2_IS_ACTIVE (self->v4l2capture))) {
588     GstBufferPool *pool = GST_BUFFER_POOL (self->v4l2output->pool);
589     GstVideoInfo info;
590     GstVideoCodecState *output_state;
591     GstBuffer *codec_data;
592     GstCaps *acquired_caps, *available_caps, *caps, *filter;
593     GstStructure *st;
594 
595     GST_DEBUG_OBJECT (self, "Sending header");
596 
597     codec_data = self->input_state->codec_data;
598 
599     /* We are running in byte-stream mode, so we don't know the headers, but
600      * we need to send something, otherwise the decoder will refuse to
601      * intialize.
602      */
603     if (codec_data) {
604       gst_buffer_ref (codec_data);
605     } else {
606       codec_data = gst_buffer_ref (frame->input_buffer);
607       processed = TRUE;
608     }
609 
610     /* Ensure input internal pool is active */
611     if (!gst_buffer_pool_is_active (pool)) {
612       GstStructure *config = gst_buffer_pool_get_config (pool);
613       gst_buffer_pool_config_set_params (config, self->input_state->caps,
614           self->v4l2output->info.size, 2, 2);
615 
616       /* There is no reason to refuse this config */
617       if (!gst_buffer_pool_set_config (pool, config))
618         goto activate_failed;
619 
620       if (!gst_buffer_pool_set_active (pool, TRUE))
621         goto activate_failed;
622     }
623 
624     GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
625     ret =
626         gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->
627             v4l2output->pool), &codec_data);
628     GST_VIDEO_DECODER_STREAM_LOCK (decoder);
629 
630     gst_buffer_unref (codec_data);
631 
632     /* For decoders G_FMT returns coded size, G_SELECTION returns visible size
633      * in the compose rectangle. gst_v4l2_object_acquire_format() checks both
634      * and returns the visible size as with/height and the coded size as
635      * padding. */
636     if (!gst_v4l2_object_acquire_format (self->v4l2capture, &info))
637       goto not_negotiated;
638 
639     /* Create caps from the acquired format, remove the format field */
640     acquired_caps = gst_video_info_to_caps (&info);
641     GST_DEBUG_OBJECT (self, "Acquired caps: %" GST_PTR_FORMAT, acquired_caps);
642     st = gst_caps_get_structure (acquired_caps, 0);
643     gst_structure_remove_fields (st, "format", "colorimetry", "chroma-site",
644         NULL);
645 
646     /* Probe currently available pixel formats */
647     available_caps = gst_caps_copy (self->probed_srccaps);
648     GST_DEBUG_OBJECT (self, "Available caps: %" GST_PTR_FORMAT, available_caps);
649 
650     /* Replace coded size with visible size, we want to negotiate visible size
651      * with downstream, not coded size. */
652     gst_caps_map_in_place (available_caps, gst_v4l2_video_remove_padding, self);
653 
654     filter = gst_caps_intersect_full (available_caps, acquired_caps,
655         GST_CAPS_INTERSECT_FIRST);
656     GST_DEBUG_OBJECT (self, "Filtered caps: %" GST_PTR_FORMAT, filter);
657     gst_caps_unref (acquired_caps);
658     gst_caps_unref (available_caps);
659     caps = gst_pad_peer_query_caps (decoder->srcpad, filter);
660     gst_caps_unref (filter);
661 
662     GST_DEBUG_OBJECT (self, "Possible decoded caps: %" GST_PTR_FORMAT, caps);
663     if (gst_caps_is_empty (caps)) {
664       gst_caps_unref (caps);
665       goto not_negotiated;
666     }
667 
668     /* Fixate pixel format */
669     caps = gst_caps_fixate (caps);
670 
671     GST_DEBUG_OBJECT (self, "Chosen decoded caps: %" GST_PTR_FORMAT, caps);
672 
673     /* Try to set negotiated format, on success replace acquired format */
674     if (gst_v4l2_object_set_format (self->v4l2capture, caps, &error))
675       gst_video_info_from_caps (&info, caps);
676     else
677       gst_v4l2_clear_error (&error);
678     gst_caps_unref (caps);
679 
680     output_state = gst_video_decoder_set_output_state (decoder,
681         info.finfo->format, info.width, info.height, self->input_state);
682 
683     /* Copy the rest of the information, there might be more in the future */
684     output_state->info.interlace_mode = info.interlace_mode;
685     gst_video_codec_state_unref (output_state);
686 
687     if (!gst_video_decoder_negotiate (decoder)) {
688       if (GST_PAD_IS_FLUSHING (decoder->srcpad))
689         goto flushing;
690       else
691         goto not_negotiated;
692     }
693 
694     /* Ensure our internal pool is activated */
695     if (!gst_buffer_pool_set_active (GST_BUFFER_POOL (self->v4l2capture->pool),
696             TRUE))
697       goto activate_failed;
698   }
699 
700   task_state = gst_pad_get_task_state (GST_VIDEO_DECODER_SRC_PAD (self));
701   if (task_state == GST_TASK_STOPPED || task_state == GST_TASK_PAUSED) {
702     /* It's possible that the processing thread stopped due to an error */
703     if (self->output_flow != GST_FLOW_OK &&
704         self->output_flow != GST_FLOW_FLUSHING) {
705       GST_DEBUG_OBJECT (self, "Processing loop stopped with error, leaving");
706       ret = self->output_flow;
707       goto drop;
708     }
709 
710     GST_DEBUG_OBJECT (self, "Starting decoding thread");
711 
712     /* Start the processing task, when it quits, the task will disable input
713      * processing to unlock input if draining, or prevent potential block */
714     self->output_flow = GST_FLOW_FLUSHING;
715     if (!gst_pad_start_task (decoder->srcpad,
716             (GstTaskFunction) gst_v4l2_video_dec_loop, self, NULL))
717       goto start_task_failed;
718   }
719 
720   if (!processed) {
721     GST_VIDEO_DECODER_STREAM_UNLOCK (decoder);
722     ret =
723         gst_v4l2_buffer_pool_process (GST_V4L2_BUFFER_POOL (self->v4l2output->
724             pool), &frame->input_buffer);
725     GST_VIDEO_DECODER_STREAM_LOCK (decoder);
726 
727     if (ret == GST_FLOW_FLUSHING) {
728       if (gst_pad_get_task_state (GST_VIDEO_DECODER_SRC_PAD (self)) !=
729           GST_TASK_STARTED)
730         ret = self->output_flow;
731       goto drop;
732     } else if (ret != GST_FLOW_OK) {
733       goto process_failed;
734     }
735   }
736 
737   /* No need to keep input arround */
738   tmp = frame->input_buffer;
739   frame->input_buffer = gst_buffer_new ();
740   gst_buffer_copy_into (frame->input_buffer, tmp,
741       GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS |
742       GST_BUFFER_COPY_META, 0, 0);
743   gst_buffer_unref (tmp);
744 
745   gst_video_codec_frame_unref (frame);
746   return ret;
747 
748   /* ERRORS */
749 not_negotiated:
750   {
751     GST_ERROR_OBJECT (self, "not negotiated");
752     ret = GST_FLOW_NOT_NEGOTIATED;
753     gst_v4l2_error (self, &error);
754     goto drop;
755   }
756 activate_failed:
757   {
758     GST_ELEMENT_ERROR (self, RESOURCE, SETTINGS,
759         (_("Failed to allocate required memory.")),
760         ("Buffer pool activation failed"));
761     ret = GST_FLOW_ERROR;
762     goto drop;
763   }
764 flushing:
765   {
766     ret = GST_FLOW_FLUSHING;
767     goto drop;
768   }
769 
770 start_task_failed:
771   {
772     GST_ELEMENT_ERROR (self, RESOURCE, FAILED,
773         (_("Failed to start decoding thread.")), (NULL));
774     ret = GST_FLOW_ERROR;
775     goto drop;
776   }
777 process_failed:
778   {
779     GST_ELEMENT_ERROR (self, RESOURCE, FAILED,
780         (_("Failed to process frame.")),
781         ("Maybe be due to not enough memory or failing driver"));
782     ret = GST_FLOW_ERROR;
783     goto drop;
784   }
785 drop:
786   {
787     gst_video_decoder_drop_frame (decoder, frame);
788     return ret;
789   }
790 }
791 
792 static gboolean
gst_v4l2_video_dec_decide_allocation(GstVideoDecoder * decoder,GstQuery * query)793 gst_v4l2_video_dec_decide_allocation (GstVideoDecoder * decoder,
794     GstQuery * query)
795 {
796   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
797   GstClockTime latency;
798   gboolean ret = FALSE;
799 
800   if (gst_v4l2_object_decide_allocation (self->v4l2capture, query))
801     ret = GST_VIDEO_DECODER_CLASS (parent_class)->decide_allocation (decoder,
802         query);
803 
804   if (GST_CLOCK_TIME_IS_VALID (self->v4l2capture->duration)) {
805     latency = self->v4l2capture->min_buffers * self->v4l2capture->duration;
806     GST_DEBUG_OBJECT (self, "Setting latency: %" GST_TIME_FORMAT " (%"
807         G_GUINT32_FORMAT " * %" G_GUINT64_FORMAT, GST_TIME_ARGS (latency),
808         self->v4l2capture->min_buffers, self->v4l2capture->duration);
809     gst_video_decoder_set_latency (decoder, latency, latency);
810   } else {
811     GST_WARNING_OBJECT (self, "Duration invalid, not setting latency");
812   }
813 
814   return ret;
815 }
816 
817 static gboolean
gst_v4l2_video_dec_src_query(GstVideoDecoder * decoder,GstQuery * query)818 gst_v4l2_video_dec_src_query (GstVideoDecoder * decoder, GstQuery * query)
819 {
820   gboolean ret = TRUE;
821   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
822 
823   switch (GST_QUERY_TYPE (query)) {
824     case GST_QUERY_CAPS:{
825       GstCaps *filter, *result = NULL;
826       GstPad *pad = GST_VIDEO_DECODER_SRC_PAD (decoder);
827 
828       gst_query_parse_caps (query, &filter);
829 
830       if (self->probed_srccaps)
831         result = gst_caps_ref (self->probed_srccaps);
832       else
833         result = gst_pad_get_pad_template_caps (pad);
834 
835       if (filter) {
836         GstCaps *tmp = result;
837         result =
838             gst_caps_intersect_full (filter, tmp, GST_CAPS_INTERSECT_FIRST);
839         gst_caps_unref (tmp);
840       }
841 
842       GST_DEBUG_OBJECT (self, "Returning src caps %" GST_PTR_FORMAT, result);
843 
844       gst_query_set_caps_result (query, result);
845       gst_caps_unref (result);
846       break;
847     }
848 
849     default:
850       ret = GST_VIDEO_DECODER_CLASS (parent_class)->src_query (decoder, query);
851       break;
852   }
853 
854   return ret;
855 }
856 
857 static GstCaps *
gst_v4l2_video_dec_sink_getcaps(GstVideoDecoder * decoder,GstCaps * filter)858 gst_v4l2_video_dec_sink_getcaps (GstVideoDecoder * decoder, GstCaps * filter)
859 {
860   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
861   GstCaps *result;
862 
863   result = gst_video_decoder_proxy_getcaps (decoder, self->probed_sinkcaps,
864       filter);
865 
866   GST_DEBUG_OBJECT (self, "Returning sink caps %" GST_PTR_FORMAT, result);
867 
868   return result;
869 }
870 
871 static gboolean
gst_v4l2_video_dec_sink_event(GstVideoDecoder * decoder,GstEvent * event)872 gst_v4l2_video_dec_sink_event (GstVideoDecoder * decoder, GstEvent * event)
873 {
874   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (decoder);
875   gboolean ret;
876   GstEventType type = GST_EVENT_TYPE (event);
877 
878   switch (type) {
879     case GST_EVENT_FLUSH_START:
880       GST_DEBUG_OBJECT (self, "flush start");
881       gst_v4l2_object_unlock (self->v4l2output);
882       gst_v4l2_object_unlock (self->v4l2capture);
883       break;
884     default:
885       break;
886   }
887 
888   ret = GST_VIDEO_DECODER_CLASS (parent_class)->sink_event (decoder, event);
889 
890   switch (type) {
891     case GST_EVENT_FLUSH_START:
892       /* The processing thread should stop now, wait for it */
893       gst_pad_stop_task (decoder->srcpad);
894       GST_DEBUG_OBJECT (self, "flush start done");
895       break;
896     default:
897       break;
898   }
899 
900   return ret;
901 }
902 
903 static GstStateChangeReturn
gst_v4l2_video_dec_change_state(GstElement * element,GstStateChange transition)904 gst_v4l2_video_dec_change_state (GstElement * element,
905     GstStateChange transition)
906 {
907   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (element);
908   GstVideoDecoder *decoder = GST_VIDEO_DECODER (element);
909 
910   if (transition == GST_STATE_CHANGE_PAUSED_TO_READY) {
911     g_atomic_int_set (&self->active, FALSE);
912     gst_v4l2_object_unlock (self->v4l2output);
913     gst_v4l2_object_unlock (self->v4l2capture);
914     gst_pad_stop_task (decoder->srcpad);
915   }
916 
917   return GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
918 }
919 
920 static void
gst_v4l2_video_dec_dispose(GObject * object)921 gst_v4l2_video_dec_dispose (GObject * object)
922 {
923   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (object);
924 
925   gst_caps_replace (&self->probed_sinkcaps, NULL);
926   gst_caps_replace (&self->probed_srccaps, NULL);
927 
928   G_OBJECT_CLASS (parent_class)->dispose (object);
929 }
930 
931 static void
gst_v4l2_video_dec_finalize(GObject * object)932 gst_v4l2_video_dec_finalize (GObject * object)
933 {
934   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (object);
935 
936   gst_v4l2_object_destroy (self->v4l2capture);
937   gst_v4l2_object_destroy (self->v4l2output);
938 
939   G_OBJECT_CLASS (parent_class)->finalize (object);
940 }
941 
942 static void
gst_v4l2_video_dec_init(GstV4l2VideoDec * self)943 gst_v4l2_video_dec_init (GstV4l2VideoDec * self)
944 {
945   /* V4L2 object are created in subinstance_init */
946 }
947 
948 static void
gst_v4l2_video_dec_subinstance_init(GTypeInstance * instance,gpointer g_class)949 gst_v4l2_video_dec_subinstance_init (GTypeInstance * instance, gpointer g_class)
950 {
951   GstV4l2VideoDecClass *klass = GST_V4L2_VIDEO_DEC_CLASS (g_class);
952   GstV4l2VideoDec *self = GST_V4L2_VIDEO_DEC (instance);
953   GstVideoDecoder *decoder = GST_VIDEO_DECODER (instance);
954 
955   gst_video_decoder_set_packetized (decoder, TRUE);
956 
957   self->v4l2output = gst_v4l2_object_new (GST_ELEMENT (self),
958       GST_OBJECT (GST_VIDEO_DECODER_SINK_PAD (self)),
959       V4L2_BUF_TYPE_VIDEO_OUTPUT, klass->default_device,
960       gst_v4l2_get_output, gst_v4l2_set_output, NULL);
961   self->v4l2output->no_initial_format = TRUE;
962   self->v4l2output->keep_aspect = FALSE;
963 
964   self->v4l2capture = gst_v4l2_object_new (GST_ELEMENT (self),
965       GST_OBJECT (GST_VIDEO_DECODER_SRC_PAD (self)),
966       V4L2_BUF_TYPE_VIDEO_CAPTURE, klass->default_device,
967       gst_v4l2_get_input, gst_v4l2_set_input, NULL);
968 }
969 
970 static void
gst_v4l2_video_dec_class_init(GstV4l2VideoDecClass * klass)971 gst_v4l2_video_dec_class_init (GstV4l2VideoDecClass * klass)
972 {
973   GstElementClass *element_class;
974   GObjectClass *gobject_class;
975   GstVideoDecoderClass *video_decoder_class;
976 
977   parent_class = g_type_class_peek_parent (klass);
978 
979   element_class = (GstElementClass *) klass;
980   gobject_class = (GObjectClass *) klass;
981   video_decoder_class = (GstVideoDecoderClass *) klass;
982 
983   GST_DEBUG_CATEGORY_INIT (gst_v4l2_video_dec_debug, "v4l2videodec", 0,
984       "V4L2 Video Decoder");
985 
986   gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_dispose);
987   gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_finalize);
988   gobject_class->set_property =
989       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_set_property);
990   gobject_class->get_property =
991       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_get_property);
992 
993   video_decoder_class->open = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_open);
994   video_decoder_class->close = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_close);
995   video_decoder_class->start = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_start);
996   video_decoder_class->stop = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_stop);
997   video_decoder_class->finish = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_finish);
998   video_decoder_class->flush = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_flush);
999   video_decoder_class->drain = GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_drain);
1000   video_decoder_class->set_format =
1001       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_set_format);
1002   video_decoder_class->negotiate =
1003       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_negotiate);
1004   video_decoder_class->decide_allocation =
1005       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_decide_allocation);
1006   /* FIXME propose_allocation or not ? */
1007   video_decoder_class->handle_frame =
1008       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_handle_frame);
1009   video_decoder_class->getcaps =
1010       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_sink_getcaps);
1011   video_decoder_class->src_query =
1012       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_src_query);
1013   video_decoder_class->sink_event =
1014       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_sink_event);
1015 
1016   element_class->change_state =
1017       GST_DEBUG_FUNCPTR (gst_v4l2_video_dec_change_state);
1018 
1019   gst_v4l2_object_install_m2m_properties_helper (gobject_class);
1020 }
1021 
1022 static void
gst_v4l2_video_dec_subclass_init(gpointer g_class,gpointer data)1023 gst_v4l2_video_dec_subclass_init (gpointer g_class, gpointer data)
1024 {
1025   GstV4l2VideoDecClass *klass = GST_V4L2_VIDEO_DEC_CLASS (g_class);
1026   GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
1027   GstV4l2VideoDecCData *cdata = data;
1028 
1029   klass->default_device = cdata->device;
1030 
1031   /* Note: gst_pad_template_new() take the floating ref from the caps */
1032   gst_element_class_add_pad_template (element_class,
1033       gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS,
1034           cdata->sink_caps));
1035   gst_element_class_add_pad_template (element_class,
1036       gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
1037           cdata->src_caps));
1038 
1039   gst_element_class_set_static_metadata (element_class, cdata->longname,
1040       "Codec/Decoder/Video/Hardware", cdata->description,
1041       "Nicolas Dufresne <nicolas.dufresne@collabora.com>");
1042 
1043   gst_caps_unref (cdata->sink_caps);
1044   gst_caps_unref (cdata->src_caps);
1045   g_free (cdata);
1046 }
1047 
1048 /* Probing functions */
1049 gboolean
gst_v4l2_is_video_dec(GstCaps * sink_caps,GstCaps * src_caps)1050 gst_v4l2_is_video_dec (GstCaps * sink_caps, GstCaps * src_caps)
1051 {
1052   gboolean ret = FALSE;
1053 
1054   if (gst_caps_is_subset (sink_caps, gst_v4l2_object_get_codec_caps ())
1055       && gst_caps_is_subset (src_caps, gst_v4l2_object_get_raw_caps ()))
1056     ret = TRUE;
1057 
1058   return ret;
1059 }
1060 
1061 static gchar *
gst_v4l2_video_dec_set_metadata(GstStructure * s,GstV4l2VideoDecCData * cdata,const gchar * basename)1062 gst_v4l2_video_dec_set_metadata (GstStructure * s, GstV4l2VideoDecCData * cdata,
1063     const gchar * basename)
1064 {
1065   gchar *codec_name = NULL;
1066   gchar *type_name = NULL;
1067 
1068 #define SET_META(codec) \
1069 G_STMT_START { \
1070   cdata->longname = "V4L2 " codec " Decoder"; \
1071   cdata->description = "Decodes " codec " streams via V4L2 API"; \
1072   codec_name = g_ascii_strdown (codec, -1); \
1073 } G_STMT_END
1074 
1075   if (gst_structure_has_name (s, "image/jpeg")) {
1076     SET_META ("JPEG");
1077   } else if (gst_structure_has_name (s, "video/mpeg")) {
1078     gint mpegversion = 0;
1079     gst_structure_get_int (s, "mpegversion", &mpegversion);
1080 
1081     if (mpegversion == 2) {
1082       SET_META ("MPEG2");
1083     } else {
1084       SET_META ("MPEG4");
1085     }
1086   } else if (gst_structure_has_name (s, "video/x-h263")) {
1087     SET_META ("H263");
1088   } else if (gst_structure_has_name (s, "video/x-fwht")) {
1089     SET_META ("FWHT");
1090   } else if (gst_structure_has_name (s, "video/x-h264")) {
1091     SET_META ("H264");
1092   } else if (gst_structure_has_name (s, "video/x-h265")) {
1093     SET_META ("H265");
1094   } else if (gst_structure_has_name (s, "video/x-wmv")) {
1095     SET_META ("VC1");
1096   } else if (gst_structure_has_name (s, "video/x-vp8")) {
1097     SET_META ("VP8");
1098   } else if (gst_structure_has_name (s, "video/x-vp9")) {
1099     SET_META ("VP9");
1100   } else if (gst_structure_has_name (s, "video/x-bayer")) {
1101     SET_META ("BAYER");
1102   } else if (gst_structure_has_name (s, "video/x-sonix")) {
1103     SET_META ("SONIX");
1104   } else if (gst_structure_has_name (s, "video/x-pwc1")) {
1105     SET_META ("PWC1");
1106   } else if (gst_structure_has_name (s, "video/x-pwc2")) {
1107     SET_META ("PWC2");
1108   } else {
1109     /* This code should be kept on sync with the exposed CODEC type of format
1110      * from gstv4l2object.c. This warning will only occure in case we forget
1111      * to also add a format here. */
1112     gchar *s_str = gst_structure_to_string (s);
1113     g_warning ("Missing fixed name mapping for caps '%s', this is a GStreamer "
1114         "bug, please report at https://bugs.gnome.org", s_str);
1115     g_free (s_str);
1116   }
1117 
1118   if (codec_name) {
1119     type_name = g_strdup_printf ("v4l2%sdec", codec_name);
1120     if (g_type_from_name (type_name) != 0) {
1121       g_free (type_name);
1122       type_name = g_strdup_printf ("v4l2%s%sdec", basename, codec_name);
1123     }
1124 
1125     g_free (codec_name);
1126   }
1127 
1128   return type_name;
1129 #undef SET_META
1130 }
1131 
1132 void
gst_v4l2_video_dec_register(GstPlugin * plugin,const gchar * basename,const gchar * device_path,GstCaps * sink_caps,GstCaps * src_caps)1133 gst_v4l2_video_dec_register (GstPlugin * plugin, const gchar * basename,
1134     const gchar * device_path, GstCaps * sink_caps, GstCaps * src_caps)
1135 {
1136   gint i;
1137 
1138   for (i = 0; i < gst_caps_get_size (sink_caps); i++) {
1139     GstV4l2VideoDecCData *cdata;
1140     GstStructure *s;
1141     GTypeQuery type_query;
1142     GTypeInfo type_info = { 0, };
1143     GType type, subtype;
1144     gchar *type_name;
1145 
1146     s = gst_caps_get_structure (sink_caps, i);
1147 
1148     cdata = g_new0 (GstV4l2VideoDecCData, 1);
1149     cdata->device = g_strdup (device_path);
1150     cdata->sink_caps = gst_caps_new_empty ();
1151     gst_caps_append_structure (cdata->sink_caps, gst_structure_copy (s));
1152     cdata->src_caps = gst_caps_ref (src_caps);
1153     type_name = gst_v4l2_video_dec_set_metadata (s, cdata, basename);
1154 
1155     /* Skip over if we hit an unmapped type */
1156     if (!type_name) {
1157       g_free (cdata);
1158       continue;
1159     }
1160 
1161     type = gst_v4l2_video_dec_get_type ();
1162     g_type_query (type, &type_query);
1163     memset (&type_info, 0, sizeof (type_info));
1164     type_info.class_size = type_query.class_size;
1165     type_info.instance_size = type_query.instance_size;
1166     type_info.class_init = gst_v4l2_video_dec_subclass_init;
1167     type_info.class_data = cdata;
1168     type_info.instance_init = gst_v4l2_video_dec_subinstance_init;
1169 
1170     subtype = g_type_register_static (type, type_name, &type_info, 0);
1171     if (!gst_element_register (plugin, type_name, GST_RANK_PRIMARY + 1,
1172             subtype))
1173       GST_WARNING ("Failed to register plugin '%s'", type_name);
1174 
1175     g_free (type_name);
1176   }
1177 }
1178