1 /* GStreamer
2  *
3  * Copyright (C) 2001-2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
4  *               2006 Edgard Lima <edgard.lima@gmail.com>
5  *
6  * gstv4l2.c: plugin for v4l2 elements
7  *
8  * This library is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Library General Public
10  * License as published by the Free Software Foundation; either
11  * version 2 of the License, or (at your option) any later version.
12  *
13  * This library is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Library General Public License for more details.
17  *
18  * You should have received a copy of the GNU Library General Public
19  * License along with this library; if not, write to the
20  * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
21  * Boston, MA 02110-1301, USA.
22  */
23 
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27 
28 #ifndef _GNU_SOURCE
29 # define _GNU_SOURCE            /* O_CLOEXEC */
30 #endif
31 
32 #include "gst/gst-i18n-plugin.h"
33 
34 #include <gst/gst.h>
35 
36 #include <fcntl.h>
37 #include <string.h>
38 #include <sys/stat.h>
39 #include <sys/types.h>
40 #include <unistd.h>
41 
42 #include "ext/videodev2.h"
43 #include "v4l2-utils.h"
44 
45 #include "gstv4l2object.h"
46 #include "gstv4l2src.h"
47 #include "gstv4l2sink.h"
48 #include "gstv4l2radio.h"
49 #include "gstv4l2videodec.h"
50 #include "gstv4l2fwhtenc.h"
51 #include "gstv4l2h263enc.h"
52 #include "gstv4l2h264enc.h"
53 #include "gstv4l2h265enc.h"
54 #include "gstv4l2jpegenc.h"
55 #include "gstv4l2mpeg4enc.h"
56 #include "gstv4l2vp8enc.h"
57 #include "gstv4l2vp9enc.h"
58 #include "gstv4l2deviceprovider.h"
59 #include "gstv4l2transform.h"
60 
61 /* used in gstv4l2object.c and v4l2_calls.c */
62 GST_DEBUG_CATEGORY (v4l2_debug);
63 #define GST_CAT_DEFAULT v4l2_debug
64 
65 #ifdef GST_V4L2_ENABLE_PROBE
66 /* This is a minimalist probe, for speed, we only enumerate formats */
67 static GstCaps *
gst_v4l2_probe_template_caps(const gchar * device,gint video_fd,enum v4l2_buf_type type)68 gst_v4l2_probe_template_caps (const gchar * device, gint video_fd,
69     enum v4l2_buf_type type)
70 {
71   gint n;
72   struct v4l2_fmtdesc format;
73   GstCaps *caps;
74 
75   GST_DEBUG ("Getting %s format enumerations", device);
76   caps = gst_caps_new_empty ();
77 
78   for (n = 0;; n++) {
79     GstStructure *template;
80 
81     memset (&format, 0, sizeof (format));
82 
83     format.index = n;
84     format.type = type;
85 
86     if (ioctl (video_fd, VIDIOC_ENUM_FMT, &format) < 0)
87       break;                    /* end of enumeration */
88 
89     GST_LOG ("index:       %u", format.index);
90     GST_LOG ("type:        %d", format.type);
91     GST_LOG ("flags:       %08x", format.flags);
92     GST_LOG ("description: '%s'", format.description);
93     GST_LOG ("pixelformat: %" GST_FOURCC_FORMAT,
94         GST_FOURCC_ARGS (format.pixelformat));
95 
96     template = gst_v4l2_object_v4l2fourcc_to_structure (format.pixelformat);
97 
98     if (template) {
99       GstStructure *alt_t = NULL;
100 
101       switch (format.pixelformat) {
102         case V4L2_PIX_FMT_RGB32:
103           alt_t = gst_structure_copy (template);
104           gst_structure_set (alt_t, "format", G_TYPE_STRING, "ARGB", NULL);
105           break;
106         case V4L2_PIX_FMT_BGR32:
107           alt_t = gst_structure_copy (template);
108           gst_structure_set (alt_t, "format", G_TYPE_STRING, "BGRA", NULL);
109         default:
110           break;
111       }
112 
113       gst_caps_append_structure (caps, template);
114 
115       if (alt_t)
116         gst_caps_append_structure (caps, alt_t);
117     }
118   }
119 
120   return gst_caps_simplify (caps);
121 }
122 
123 static gboolean
gst_v4l2_probe_and_register(GstPlugin * plugin)124 gst_v4l2_probe_and_register (GstPlugin * plugin)
125 {
126   GstV4l2Iterator *it;
127   gint video_fd = -1;
128   struct v4l2_capability vcap;
129   guint32 device_caps;
130 
131   GST_DEBUG ("Probing devices");
132 
133   it = gst_v4l2_iterator_new ();
134 
135   while (gst_v4l2_iterator_next (it)) {
136     GstCaps *src_caps, *sink_caps;
137     gchar *basename;
138 
139     if (video_fd >= 0)
140       close (video_fd);
141 
142     video_fd = open (it->device_path, O_RDWR | O_CLOEXEC);
143 
144     if (video_fd == -1) {
145       GST_DEBUG ("Failed to open %s: %s", it->device_path, g_strerror (errno));
146       continue;
147     }
148 
149     memset (&vcap, 0, sizeof (vcap));
150 
151     if (ioctl (video_fd, VIDIOC_QUERYCAP, &vcap) < 0) {
152       GST_DEBUG ("Failed to get device capabilities: %s", g_strerror (errno));
153       continue;
154     }
155 
156     if (vcap.capabilities & V4L2_CAP_DEVICE_CAPS)
157       device_caps = vcap.device_caps;
158     else
159       device_caps = vcap.capabilities;
160 
161     if (!GST_V4L2_IS_M2M (device_caps))
162       continue;
163 
164     GST_DEBUG ("Probing '%s' located at '%s'",
165         it->device_name ? it->device_name : (const gchar *) vcap.driver,
166         it->device_path);
167 
168     /* get sink supported format (no MPLANE for codec) */
169     sink_caps = gst_caps_merge (gst_v4l2_probe_template_caps (it->device_path,
170             video_fd, V4L2_BUF_TYPE_VIDEO_OUTPUT),
171         gst_v4l2_probe_template_caps (it->device_path, video_fd,
172             V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE));
173 
174     /* get src supported format */
175     src_caps = gst_caps_merge (gst_v4l2_probe_template_caps (it->device_path,
176             video_fd, V4L2_BUF_TYPE_VIDEO_CAPTURE),
177         gst_v4l2_probe_template_caps (it->device_path, video_fd,
178             V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE));
179 
180     /* Skip devices without any supported formats */
181     if (gst_caps_is_empty (sink_caps) || gst_caps_is_empty (src_caps)) {
182       gst_caps_unref (sink_caps);
183       gst_caps_unref (src_caps);
184       continue;
185     }
186 
187     basename = g_path_get_basename (it->device_path);
188 
189     /* Caps won't be freed if the subclass is not instantiated */
190     GST_MINI_OBJECT_FLAG_SET (sink_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);
191     GST_MINI_OBJECT_FLAG_SET (src_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED);
192 
193     if (gst_v4l2_is_video_dec (sink_caps, src_caps)) {
194       gst_v4l2_video_dec_register (plugin, basename, it->device_path,
195           sink_caps, src_caps);
196     } else if (gst_v4l2_is_video_enc (sink_caps, src_caps, NULL)) {
197       if (gst_v4l2_is_fwht_enc (sink_caps, src_caps))
198         gst_v4l2_fwht_enc_register (plugin, basename, it->device_path,
199             sink_caps, src_caps);
200 
201       if (gst_v4l2_is_h264_enc (sink_caps, src_caps))
202         gst_v4l2_h264_enc_register (plugin, basename, it->device_path,
203             sink_caps, src_caps);
204 
205       if (gst_v4l2_is_h265_enc (sink_caps, src_caps))
206         gst_v4l2_h265_enc_register (plugin, basename, it->device_path,
207             sink_caps, src_caps);
208 
209       if (gst_v4l2_is_mpeg4_enc (sink_caps, src_caps))
210         gst_v4l2_mpeg4_enc_register (plugin, basename, it->device_path,
211             sink_caps, src_caps);
212 
213       if (gst_v4l2_is_h263_enc (sink_caps, src_caps))
214         gst_v4l2_h263_enc_register (plugin, basename, it->device_path,
215             sink_caps, src_caps);
216 
217       if (gst_v4l2_is_jpeg_enc (sink_caps, src_caps))
218         gst_v4l2_jpeg_enc_register (plugin, basename, it->device_path,
219             sink_caps, src_caps);
220 
221       if (gst_v4l2_is_vp8_enc (sink_caps, src_caps))
222         gst_v4l2_vp8_enc_register (plugin, basename, it->device_path,
223             sink_caps, src_caps);
224 
225       if (gst_v4l2_is_vp9_enc (sink_caps, src_caps))
226         gst_v4l2_vp9_enc_register (plugin, basename, it->device_path,
227             sink_caps, src_caps);
228     } else if (gst_v4l2_is_transform (sink_caps, src_caps)) {
229       gst_v4l2_transform_register (plugin, basename, it->device_path,
230           sink_caps, src_caps);
231     }
232     /* else if ( ... etc. */
233 
234     gst_caps_unref (sink_caps);
235     gst_caps_unref (src_caps);
236     g_free (basename);
237   }
238 
239   if (video_fd >= 0)
240     close (video_fd);
241 
242   gst_v4l2_iterator_free (it);
243 
244   return TRUE;
245 }
246 #endif
247 
248 static gboolean
plugin_init(GstPlugin * plugin)249 plugin_init (GstPlugin * plugin)
250 {
251   const gchar *paths[] = { "/dev", "/dev/v4l2", NULL };
252   const gchar *names[] = { "video", NULL };
253 
254   GST_DEBUG_CATEGORY_INIT (v4l2_debug, "v4l2", 0, "V4L2 API calls");
255 
256   /* Add some depedency, so the dynamic features get updated upon changes in
257    * /dev/video* */
258   gst_plugin_add_dependency (plugin,
259       NULL, paths, names, GST_PLUGIN_DEPENDENCY_FLAG_FILE_NAME_IS_PREFIX);
260 
261   if (!gst_element_register (plugin, "v4l2src", GST_RANK_PRIMARY,
262           GST_TYPE_V4L2SRC) ||
263       !gst_element_register (plugin, "v4l2sink", GST_RANK_NONE,
264           GST_TYPE_V4L2SINK) ||
265       !gst_element_register (plugin, "v4l2radio", GST_RANK_NONE,
266           GST_TYPE_V4L2RADIO) ||
267       !gst_device_provider_register (plugin, "v4l2deviceprovider",
268           GST_RANK_PRIMARY, GST_TYPE_V4L2_DEVICE_PROVIDER)
269       /* etc. */
270 #ifdef GST_V4L2_ENABLE_PROBE
271       || !gst_v4l2_probe_and_register (plugin)
272 #endif
273       )
274     return FALSE;
275 
276 #ifdef ENABLE_NLS
277   bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
278   bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
279 #endif /* ENABLE_NLS */
280 
281   return TRUE;
282 }
283 
284 GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
285     GST_VERSION_MINOR,
286     video4linux2,
287     "elements for Video 4 Linux",
288     plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)
289