1 /* GStreamer
2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
4 * 2005 Wim Taymans <wim@fluendo.com>
5 * 2005 David Schleef <ds@schleef.org>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
16 *
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
21 */
22 /**
23 * SECTION:element-capsfilter
24 *
25 * The element does not modify data as such, but can enforce limitations on the
26 * data format.
27 *
28 * <refsect2>
29 * <title>Example launch line</title>
30 * |[
31 * gst-launch videotestsrc ! video/x-raw-gray ! ffmpegcolorspace ! autovideosink
32 * ]| Limits acceptable video from videotestsrc to be grayscale.
33 * </refsect2>
34 */
36 #ifdef HAVE_CONFIG_H
37 #include "config.h"
38 #endif
40 #include "../../gst/gst-i18n-lib.h"
41 #include "gstcapsfilter.h"
43 enum
44 {
45 PROP_0,
46 PROP_FILTER_CAPS
47 };
50 static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink",
51 GST_PAD_SINK,
52 GST_PAD_ALWAYS,
53 GST_STATIC_CAPS_ANY);
55 static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src",
56 GST_PAD_SRC,
57 GST_PAD_ALWAYS,
58 GST_STATIC_CAPS_ANY);
61 GST_DEBUG_CATEGORY_STATIC (gst_capsfilter_debug);
62 #define GST_CAT_DEFAULT gst_capsfilter_debug
64 #define _do_init(bla) \
65 GST_DEBUG_CATEGORY_INIT (gst_capsfilter_debug, "capsfilter", 0, \
66 "capsfilter element");
68 GST_BOILERPLATE_FULL (GstCapsFilter, gst_capsfilter, GstBaseTransform,
69 GST_TYPE_BASE_TRANSFORM, _do_init);
72 static void gst_capsfilter_set_property (GObject * object, guint prop_id,
73 const GValue * value, GParamSpec * pspec);
74 static void gst_capsfilter_get_property (GObject * object, guint prop_id,
75 GValue * value, GParamSpec * pspec);
76 static void gst_capsfilter_dispose (GObject * object);
78 static GstCaps *gst_capsfilter_transform_caps (GstBaseTransform * base,
79 GstPadDirection direction, GstCaps * caps);
80 static gboolean gst_capsfilter_accept_caps (GstBaseTransform * base,
81 GstPadDirection direction, GstCaps * caps);
82 static GstFlowReturn gst_capsfilter_transform_ip (GstBaseTransform * base,
83 GstBuffer * buf);
84 static GstFlowReturn gst_capsfilter_prepare_buf (GstBaseTransform * trans,
85 GstBuffer * input, gint size, GstCaps * caps, GstBuffer ** buf);
87 static void
88 gst_capsfilter_base_init (gpointer g_class)
89 {
90 GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
92 gst_element_class_set_details_simple (gstelement_class,
93 "CapsFilter",
94 "Generic",
95 "Pass data without modification, limiting formats",
96 "David Schleef <ds@schleef.org>");
97 gst_element_class_add_pad_template (gstelement_class,
98 gst_static_pad_template_get (&srctemplate));
99 gst_element_class_add_pad_template (gstelement_class,
100 gst_static_pad_template_get (&sinktemplate));
101 }
103 static void
104 gst_capsfilter_class_init (GstCapsFilterClass * klass)
105 {
106 GObjectClass *gobject_class;
107 GstBaseTransformClass *trans_class;
109 gobject_class = G_OBJECT_CLASS (klass);
110 gobject_class->set_property = gst_capsfilter_set_property;
111 gobject_class->get_property = gst_capsfilter_get_property;
112 gobject_class->dispose = gst_capsfilter_dispose;
114 g_object_class_install_property (gobject_class, PROP_FILTER_CAPS,
115 g_param_spec_boxed ("caps", _("Filter caps"),
116 _("Restrict the possible allowed capabilities (NULL means ANY). "
117 "Setting this property takes a reference to the supplied GstCaps "
118 "object."), GST_TYPE_CAPS,
119 G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
121 trans_class = GST_BASE_TRANSFORM_CLASS (klass);
122 trans_class->transform_caps =
123 GST_DEBUG_FUNCPTR (gst_capsfilter_transform_caps);
124 trans_class->transform_ip = GST_DEBUG_FUNCPTR (gst_capsfilter_transform_ip);
125 trans_class->accept_caps = GST_DEBUG_FUNCPTR (gst_capsfilter_accept_caps);
126 trans_class->prepare_output_buffer =
127 GST_DEBUG_FUNCPTR (gst_capsfilter_prepare_buf);
128 }
130 static void
131 gst_capsfilter_init (GstCapsFilter * filter, GstCapsFilterClass * g_class)
132 {
133 GstBaseTransform *trans = GST_BASE_TRANSFORM (filter);
134 gst_base_transform_set_gap_aware (trans, TRUE);
135 filter->filter_caps = gst_caps_new_any ();
136 }
138 static gboolean
139 copy_func (GQuark field_id, const GValue * value, GstStructure * dest)
140 {
141 gst_structure_id_set_value (dest, field_id, value);
143 return TRUE;
144 }
146 static void
147 gst_capsfilter_set_property (GObject * object, guint prop_id,
148 const GValue * value, GParamSpec * pspec)
149 {
150 GstCapsFilter *capsfilter = GST_CAPSFILTER (object);
152 switch (prop_id) {
153 case PROP_FILTER_CAPS:{
154 GstCaps *new_caps;
155 GstCaps *old_caps, *suggest, *nego;
156 const GstCaps *new_caps_val = gst_value_get_caps (value);
158 if (new_caps_val == NULL) {
159 new_caps = gst_caps_new_any ();
160 } else {
161 new_caps = (GstCaps *) new_caps_val;
162 gst_caps_ref (new_caps);
163 }
165 GST_OBJECT_LOCK (capsfilter);
166 old_caps = capsfilter->filter_caps;
167 capsfilter->filter_caps = new_caps;
168 GST_OBJECT_UNLOCK (capsfilter);
170 gst_caps_unref (old_caps);
172 GST_DEBUG_OBJECT (capsfilter, "set new caps %" GST_PTR_FORMAT, new_caps);
174 /* filter the currently negotiated format against the new caps */
175 GST_OBJECT_LOCK (GST_BASE_TRANSFORM_SINK_PAD (object));
176 nego = GST_PAD_CAPS (GST_BASE_TRANSFORM_SINK_PAD (object));
177 if (nego) {
178 GST_DEBUG_OBJECT (capsfilter, "we had negotiated caps %" GST_PTR_FORMAT,
179 nego);
181 if (G_UNLIKELY (gst_caps_is_any (new_caps))) {
182 GST_DEBUG_OBJECT (capsfilter, "not settings any suggestion");
184 suggest = NULL;
185 } else {
186 GstStructure *s1, *s2;
188 /* first check if the name is the same */
189 s1 = gst_caps_get_structure (nego, 0);
190 s2 = gst_caps_get_structure (new_caps, 0);
192 if (gst_structure_get_name_id (s1) == gst_structure_get_name_id (s2)) {
193 /* same name, copy all fields from the new caps into the previously
194 * negotiated caps */
195 suggest = gst_caps_copy (nego);
196 s1 = gst_caps_get_structure (suggest, 0);
197 gst_structure_foreach (s2, (GstStructureForeachFunc) copy_func, s1);
198 GST_DEBUG_OBJECT (capsfilter, "copied structure fields");
199 } else {
200 GST_DEBUG_OBJECT (capsfilter, "different structure names");
201 /* different names, we can only suggest the complete caps */
202 suggest = gst_caps_copy (new_caps);
203 }
204 }
205 } else {
206 GST_DEBUG_OBJECT (capsfilter, "no negotiated caps");
207 /* Suggest the new caps, we can't just rely on _get_caps as this may
208 * already be called at this point even though no buffer has been
209 * pushed yet */
210 suggest = gst_caps_copy (new_caps);
211 }
212 GST_OBJECT_UNLOCK (GST_BASE_TRANSFORM_SINK_PAD (object));
214 GST_DEBUG_OBJECT (capsfilter, "suggesting new caps %" GST_PTR_FORMAT,
215 suggest);
216 gst_base_transform_suggest (GST_BASE_TRANSFORM (object), suggest, 0);
217 if (suggest)
218 gst_caps_unref (suggest);
220 break;
221 }
222 default:
223 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
224 break;
225 }
226 }
228 static void
229 gst_capsfilter_get_property (GObject * object, guint prop_id, GValue * value,
230 GParamSpec * pspec)
231 {
232 GstCapsFilter *capsfilter = GST_CAPSFILTER (object);
234 switch (prop_id) {
235 case PROP_FILTER_CAPS:
236 GST_OBJECT_LOCK (capsfilter);
237 gst_value_set_caps (value, capsfilter->filter_caps);
238 GST_OBJECT_UNLOCK (capsfilter);
239 break;
240 default:
241 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
242 break;
243 }
244 }
246 static void
247 gst_capsfilter_dispose (GObject * object)
248 {
249 GstCapsFilter *filter = GST_CAPSFILTER (object);
251 gst_caps_replace (&filter->filter_caps, NULL);
253 G_OBJECT_CLASS (parent_class)->dispose (object);
254 }
256 static GstCaps *
257 gst_capsfilter_transform_caps (GstBaseTransform * base,
258 GstPadDirection direction, GstCaps * caps)
259 {
260 GstCapsFilter *capsfilter = GST_CAPSFILTER (base);
261 GstCaps *ret, *filter_caps;
263 GST_OBJECT_LOCK (capsfilter);
264 filter_caps = gst_caps_ref (capsfilter->filter_caps);
265 GST_OBJECT_UNLOCK (capsfilter);
267 ret = gst_caps_intersect (caps, filter_caps);
268 GST_DEBUG_OBJECT (capsfilter, "input: %" GST_PTR_FORMAT, caps);
269 GST_DEBUG_OBJECT (capsfilter, "filter: %" GST_PTR_FORMAT, filter_caps);
270 GST_DEBUG_OBJECT (capsfilter, "intersect: %" GST_PTR_FORMAT, ret);
272 gst_caps_unref (filter_caps);
274 return ret;
275 }
277 static gboolean
278 gst_capsfilter_accept_caps (GstBaseTransform * base,
279 GstPadDirection direction, GstCaps * caps)
280 {
281 GstCapsFilter *capsfilter = GST_CAPSFILTER (base);
282 GstCaps *filter_caps;
283 gboolean ret;
285 GST_OBJECT_LOCK (capsfilter);
286 filter_caps = gst_caps_ref (capsfilter->filter_caps);
287 GST_OBJECT_UNLOCK (capsfilter);
289 ret = gst_caps_can_intersect (caps, filter_caps);
290 GST_DEBUG_OBJECT (capsfilter, "can intersect: %d", ret);
291 if (ret) {
292 /* if we can intersect, see if the other end also accepts */
293 if (direction == GST_PAD_SRC)
294 ret = gst_pad_peer_accept_caps (GST_BASE_TRANSFORM_SINK_PAD (base), caps);
295 else
296 ret = gst_pad_peer_accept_caps (GST_BASE_TRANSFORM_SRC_PAD (base), caps);
297 GST_DEBUG_OBJECT (capsfilter, "peer accept: %d", ret);
298 }
300 gst_caps_unref (filter_caps);
302 return ret;
303 }
305 static GstFlowReturn
306 gst_capsfilter_transform_ip (GstBaseTransform * base, GstBuffer * buf)
307 {
308 /* No actual work here. It's all done in the prepare output buffer
309 * func. */
310 return GST_FLOW_OK;
311 }
313 /* Output buffer preparation... if the buffer has no caps, and
314 * our allowed output caps is fixed, then give the caps to the
315 * buffer.
316 * This ensures that outgoing buffers have caps if we can, so
317 * that pipelines like:
318 * gst-launch filesrc location=rawsamples.raw !
319 * audio/x-raw-int,width=16,depth=16,rate=48000,channels=2,
320 * endianness=4321,signed='(boolean)'true ! alsasink
321 * will work.
322 */
323 static GstFlowReturn
324 gst_capsfilter_prepare_buf (GstBaseTransform * trans, GstBuffer * input,
325 gint size, GstCaps * caps, GstBuffer ** buf)
326 {
327 GstFlowReturn ret = GST_FLOW_OK;
329 if (GST_BUFFER_CAPS (input) != NULL) {
330 /* Output buffer already has caps */
331 GST_LOG_OBJECT (trans, "Input buffer already has caps (implicitly fixed)");
332 /* FIXME : Move this behaviour to basetransform. The given caps are the ones
333 * of the source pad, therefore our outgoing buffers should always have
334 * those caps. */
335 if (GST_BUFFER_CAPS (input) != caps) {
336 /* caps are different, make a metadata writable output buffer to set
337 * caps */
338 if (gst_buffer_is_metadata_writable (input)) {
339 /* input is writable, just set caps and use this as the output */
340 *buf = input;
341 gst_buffer_set_caps (*buf, caps);
342 gst_buffer_ref (input);
343 } else {
344 GST_DEBUG_OBJECT (trans, "Creating sub-buffer and setting caps");
345 *buf = gst_buffer_create_sub (input, 0, GST_BUFFER_SIZE (input));
346 gst_buffer_set_caps (*buf, caps);
347 }
348 } else {
349 /* caps are right, just use a ref of the input as the outbuf */
350 *buf = input;
351 gst_buffer_ref (input);
352 }
353 } else {
354 /* Buffer has no caps. See if the output pad only supports fixed caps */
355 GstCaps *out_caps;
357 out_caps = GST_PAD_CAPS (trans->srcpad);
359 if (out_caps != NULL) {
360 gst_caps_ref (out_caps);
361 } else {
362 out_caps = gst_pad_get_allowed_caps (trans->srcpad);
363 g_return_val_if_fail (out_caps != NULL, GST_FLOW_ERROR);
364 }
366 out_caps = gst_caps_make_writable (out_caps);
367 gst_caps_do_simplify (out_caps);
369 if (gst_caps_is_fixed (out_caps) && !gst_caps_is_empty (out_caps)) {
370 GST_DEBUG_OBJECT (trans, "Have fixed output caps %"
371 GST_PTR_FORMAT " to apply to buffer with no caps", out_caps);
372 if (gst_buffer_is_metadata_writable (input)) {
373 gst_buffer_ref (input);
374 *buf = input;
375 } else {
376 GST_DEBUG_OBJECT (trans, "Creating sub-buffer and setting caps");
377 *buf = gst_buffer_create_sub (input, 0, GST_BUFFER_SIZE (input));
378 }
379 GST_BUFFER_CAPS (*buf) = out_caps;
381 if (GST_PAD_CAPS (trans->srcpad) == NULL)
382 gst_pad_set_caps (trans->srcpad, out_caps);
383 } else {
384 gchar *caps_str = gst_caps_to_string (out_caps);
386 GST_DEBUG_OBJECT (trans, "Cannot choose caps. Have unfixed output caps %"
387 GST_PTR_FORMAT, out_caps);
388 gst_caps_unref (out_caps);
390 ret = GST_FLOW_ERROR;
391 GST_ELEMENT_ERROR (trans, STREAM, FORMAT,
392 ("Filter caps do not completely specify the output format"),
393 ("Output caps are unfixed: %s", caps_str));
394 g_free (caps_str);
395 }
396 }
398 return ret;
399 }