1 /* G-Streamer Video4linux2 video-capture plugin - system calls
2 * Copyright (C) 2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
25 #include <sys/types.h>
28 #include <sys/ioctl.h>
32 #include "v4l2src_calls.h"
36 #define GST_CAT_DEFAULT v4l2src_debug
39 #define GST_V4L2_SET_ACTIVE(element) (element)->buffer = GINT_TO_POINTER (-1)
40 #define GST_V4L2_SET_INACTIVE(element) (element)->buffer = NULL
42 #define DEBUG(format, args...) \
43 GST_CAT_DEBUG_OBJECT (\
44 v4l2src_debug, v4l2src, \
45 "V4L2SRC: " format, ##args)
47 /* On some systems MAP_FAILED seems to be missing */
49 #define MAP_FAILED ( (caddr_t) -1 )
52 /******************************************************
53 * gst_v4l2src_fill_format_list():
54 * create list of supported capture formats
55 * return value: TRUE on success, FALSE on error
56 ******************************************************/
59 gst_v4l2src_fill_format_list (GstV4l2Src *v4l2src)
62 struct v4l2_fmtdesc *format;
64 GST_DEBUG_OBJECT (v4l2src, "getting src format enumerations");
66 /* format enumeration */
68 format = g_new (struct v4l2_fmtdesc, 1);
70 format->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
71 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_ENUM_FMT, format) < 0) {
72 if (errno == EINVAL) {
73 break; /* end of enumeration */
75 GST_ELEMENT_ERROR (v4l2src, RESOURCE, SETTINGS, (NULL),
76 ("failed to get number %d in pixelformat enumeration for %s: %s",
77 n, GST_V4L2ELEMENT(v4l2src)->device, g_strerror (errno)));
82 GST_LOG_OBJECT (v4l2src, "got format"GST_FOURCC_FORMAT,
83 GST_FOURCC_ARGS (format->pixelformat));
84 v4l2src->formats = g_slist_prepend (v4l2src->formats, format);
91 /******************************************************
92 * gst_v4l2src_clear_format_list():
93 * free list of supported capture formats
94 * return value: TRUE on success, FALSE on error
95 ******************************************************/
98 gst_v4l2src_clear_format_list (GstV4l2Src *v4l2src)
100 g_slist_foreach (v4l2src->formats, (GFunc) g_free, NULL);
101 g_slist_free (v4l2src->formats);
107 /******************************************************
108 * gst_v4l2src_queue_frame():
109 * queue a frame for capturing
110 * return value: TRUE on success, FALSE on error
111 ******************************************************/
114 gst_v4l2src_queue_frame (GstV4l2Src *v4l2src,
117 GST_LOG_OBJECT (v4l2src, "queueing frame %u", i);
119 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_QBUF, &v4l2src->pool->buffers[i].buffer) < 0) {
120 GST_ELEMENT_ERROR (v4l2src, RESOURCE, WRITE,
121 (_("Could not write to device \"%s\"."), GST_V4L2ELEMENT(v4l2src)->device),
122 ("Error queueing buffer %u on device %s", i, g_strerror(errno)));
130 /******************************************************
131 * gst_v4l2src_grab_frame ():
132 * grab a frame for capturing
133 * return value: TRUE on success, FALSE on error
134 ******************************************************/
137 gst_v4l2src_grab_frame (GstV4l2Src *v4l2src)
139 struct v4l2_buffer buffer;
141 buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
142 while (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_DQBUF, &buffer) < 0) {
143 /* if the sync() got interrupted, we can retry */
144 if (errno != EINTR) {
145 GST_ELEMENT_ERROR (v4l2src, RESOURCE, SYNC, (NULL), ("could not sync on a buffer on device %s: %s",
146 GST_V4L2ELEMENT(v4l2src)->device, g_strerror (errno)));
149 GST_DEBUG_OBJECT (v4l2src, "grab got interrupted");
152 GST_LOG_OBJECT (v4l2src, "grabbed frame %d", buffer.index);
158 /******************************************************
159 * gst_v4l2src_get_capture():
160 * get capture parameters
161 * return value: TRUE on success, FALSE on error
162 ******************************************************/
165 gst_v4l2src_get_capture (GstV4l2Src *v4l2src)
167 DEBUG("Getting capture format");
169 GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
171 v4l2src->format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
172 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_G_FMT, &v4l2src->format) < 0) {
173 GST_ELEMENT_ERROR (v4l2src, RESOURCE, SETTINGS, (NULL),
174 ("failed to get pixelformat for device %s: %s",
175 GST_V4L2ELEMENT(v4l2src)->device, g_strerror (errno)));
183 /******************************************************
184 * gst_v4l2src_set_capture():
185 * set capture parameters
186 * return value: TRUE on success, FALSE on error
187 ******************************************************/
190 gst_v4l2src_set_capture (GstV4l2Src *v4l2src,
191 struct v4l2_fmtdesc *fmt,
195 DEBUG("Setting capture format to %dx%d, format %s",
196 width, height, fmt->description);
198 GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
199 GST_V4L2_CHECK_NOT_ACTIVE(GST_V4L2ELEMENT(v4l2src));
201 memset(&v4l2src->format, 0, sizeof(struct v4l2_format));
202 v4l2src->format.fmt.pix.width = width;
203 v4l2src->format.fmt.pix.height = height;
204 v4l2src->format.fmt.pix.pixelformat = fmt->pixelformat;
205 v4l2src->format.fmt.pix.field = V4L2_FIELD_INTERLACED;
206 v4l2src->format.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
208 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_S_FMT, &v4l2src->format) < 0) {
209 GST_ELEMENT_ERROR (v4l2src, RESOURCE, SETTINGS, (NULL),
210 ("failed to set pixelformat to %s @ %dx%d for device %s: %s",
211 fmt->description, width, height, GST_V4L2ELEMENT(v4l2src)->device, g_strerror (errno)));
215 /* update internal info */
216 return gst_v4l2src_get_capture(v4l2src);;
220 /******************************************************
221 * gst_v4l2src_capture_init():
222 * initialize the capture system
223 * return value: TRUE on success, FALSE on error
224 ******************************************************/
227 gst_v4l2src_capture_init (GstV4l2Src *v4l2src)
232 GST_DEBUG_OBJECT (v4l2src, "initting the capture system");
234 GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
235 GST_V4L2_CHECK_NOT_ACTIVE(GST_V4L2ELEMENT(v4l2src));
237 /* request buffer info */
238 buffers = v4l2src->breq.count;
239 if (v4l2src->breq.count > GST_V4L2_MAX_BUFFERS) {
240 v4l2src->breq.count = GST_V4L2_MAX_BUFFERS;
242 if (v4l2src->breq.count < GST_V4L2_MIN_BUFFERS) {
243 v4l2src->breq.count = GST_V4L2_MIN_BUFFERS;
245 v4l2src->breq.type = v4l2src->format.type;
246 v4l2src->breq.memory = V4L2_MEMORY_MMAP;
247 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_REQBUFS, &v4l2src->breq) < 0) {
248 GST_ELEMENT_ERROR (v4l2src, RESOURCE, READ,
249 (_("Could not get buffers from device \"%s\"."), GST_V4L2ELEMENT(v4l2src)->device),
250 ("error requesting %d buffers: %s", v4l2src->breq.count, g_strerror (errno)));
254 if (v4l2src->breq.count < GST_V4L2_MIN_BUFFERS) {
255 GST_ELEMENT_ERROR (v4l2src, RESOURCE, READ,
256 (_("Could not get enough buffers from device \"%s\"."), GST_V4L2ELEMENT(v4l2src)->device),
257 ("we received %d, we want at least %d", v4l2src->breq.count, GST_V4L2_MIN_BUFFERS));
258 v4l2src->breq.count = buffers;
261 if (v4l2src->breq.count != buffers)
262 g_object_notify (G_OBJECT (v4l2src), "num_buffers");
264 GST_INFO_OBJECT (v4l2src, "Got %d buffers ("GST_FOURCC_FORMAT") of size %d KB\n",
265 v4l2src->breq.count, GST_FOURCC_ARGS (v4l2src->format.fmt.pix.pixelformat),
266 v4l2src->format.fmt.pix.sizeimage / 1024);
268 /* Map the buffers */
269 v4l2src->pool = g_new (GstV4l2BufferPool, 1);
270 gst_atomic_int_init (&v4l2src->pool->refcount, 1);
271 v4l2src->pool->video_fd = GST_V4L2ELEMENT (v4l2src)->video_fd;
272 v4l2src->pool->buffer_count = v4l2src->breq.count;
273 v4l2src->pool->buffers = g_new0 (GstV4l2Buffer, v4l2src->breq.count);
275 for (n = 0; n < v4l2src->breq.count; n++) {
276 GstV4l2Buffer *buffer = &v4l2src->pool->buffers[n];
278 gst_atomic_int_init (&buffer->refcount, 1);
279 buffer->pool = v4l2src->pool;
280 buffer->buffer.index = n;
281 buffer->buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
282 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_QUERYBUF, &buffer->buffer) < 0) {
283 GST_ELEMENT_ERROR (v4l2src, RESOURCE, READ, (NULL),
284 ("Could not get buffer properties of buffer %d: %s", n, g_strerror (errno)));
285 gst_v4l2src_capture_deinit(v4l2src);
288 buffer->start = mmap (0, buffer->buffer.length, PROT_READ|PROT_WRITE, MAP_SHARED,
289 GST_V4L2ELEMENT(v4l2src)->video_fd, buffer->buffer.m.offset);
290 if (buffer->start == MAP_FAILED) {
291 GST_ELEMENT_ERROR (v4l2src, RESOURCE, READ, (NULL),
292 ("Could not mmap video buffer %d: %s", n, g_strerror (errno)));
294 gst_v4l2src_capture_deinit (v4l2src);
297 buffer->length = buffer->buffer.length;
298 if (!gst_v4l2src_queue_frame(v4l2src, n)) {
299 gst_v4l2src_capture_deinit (v4l2src);
304 GST_V4L2_SET_ACTIVE(GST_V4L2ELEMENT (v4l2src));
309 /******************************************************
310 * gst_v4l2src_capture_start():
311 * start streaming capture
312 * return value: TRUE on success, FALSE on error
313 ******************************************************/
316 gst_v4l2src_capture_start (GstV4l2Src *v4l2src)
318 gint type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
320 GST_DEBUG_OBJECT (v4l2src, "starting the capturing");
322 GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
323 if (!GST_V4L2_IS_ACTIVE (GST_V4L2ELEMENT(v4l2src))) {
324 gst_pad_renegotiate (v4l2src->srcpad);
326 GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
328 v4l2src->quit = FALSE;
330 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_STREAMON, &type) < 0) {
331 GST_ELEMENT_ERROR (v4l2src, RESOURCE, OPEN_READ, (NULL),
332 ("Error starting streaming capture from device %s: %s",
333 GST_V4L2ELEMENT(v4l2src)->device, g_strerror(errno)));
341 /******************************************************
342 * gst_v4l2src_capture_stop():
343 * stop streaming capture
344 * return value: TRUE on success, FALSE on error
345 ******************************************************/
348 gst_v4l2src_capture_stop (GstV4l2Src *v4l2src)
350 gint type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
352 GST_DEBUG_OBJECT (v4l2src, "stopping capturing");
353 GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
354 GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
356 /* we actually need to sync on all queued buffers but not
357 * on the non-queued ones */
358 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_STREAMOFF, &type) < 0) {
359 GST_ELEMENT_ERROR (v4l2src, RESOURCE, CLOSE, (NULL),
360 ("Error stopping streaming capture from device %s: %s",
361 GST_V4L2ELEMENT(v4l2src)->device, g_strerror (errno)));
365 /* make an optional pending wait stop */
366 v4l2src->quit = TRUE;
372 gst_v4l2src_buffer_pool_free (GstV4l2BufferPool *pool, gboolean do_close)
376 for (i = 0; i < pool->buffer_count; i++) {
377 gst_atomic_int_destroy (&pool->buffers[i].refcount);
378 munmap (pool->buffers[i].start, pool->buffers[i].length);
380 g_free (pool->buffers);
381 gst_atomic_int_destroy (&pool->refcount);
383 close (pool->video_fd);
388 gst_v4l2src_free_buffer (GstBuffer *buffer)
390 GstV4l2Buffer *buf = (GstV4l2Buffer *) GST_BUFFER_PRIVATE (buffer);
392 GST_LOG ("freeing buffer %p (nr. %d)", buffer, buf->buffer.index);
394 if (!gst_atomic_int_dec_and_test (&buf->refcount)) {
395 /* we're still in use, add to queue again
396 note: this might fail because the device is already stopped (race) */
397 if (ioctl(buf->pool->video_fd, VIDIOC_QBUF, &buf->buffer) < 0)
398 GST_INFO ("readding to queue failed, assuming video device is stopped");
400 if (gst_atomic_int_dec_and_test (&buf->pool->refcount)) {
401 /* we're last thing that used all this */
402 gst_v4l2src_buffer_pool_free (buf->pool, TRUE);
406 /******************************************************
407 * gst_v4l2src_capture_deinit():
408 * deinitialize the capture system
409 * return value: TRUE on success, FALSE on error
410 ******************************************************/
413 gst_v4l2src_capture_deinit (GstV4l2Src *v4l2src)
417 GST_DEBUG_OBJECT (v4l2src, "deinitting capture system");
419 GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
420 GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
422 /* free the buffers */
423 for (i = 0; i < v4l2src->breq.count; i++) {
424 if (gst_atomic_int_dec_and_test (&v4l2src->pool->buffers[i].refcount))
427 for (i = 0; i < dequeue; i++) {
428 struct v4l2_buffer buffer;
429 buffer.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
430 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_DQBUF, &buffer) < 0)
431 GST_WARNING_OBJECT (v4l2src, "Could not dequeue buffer on uninitialization");
433 if (gst_atomic_int_dec_and_test (&v4l2src->pool->refcount)) {
434 /* we're last thing that used all this */
435 gst_v4l2src_buffer_pool_free (v4l2src->pool, FALSE);
437 v4l2src->pool = NULL;
439 GST_V4L2_SET_INACTIVE (GST_V4L2ELEMENT (v4l2src));
449 gst_v4l2src_get_size_limits (GstV4l2Src *v4l2src,
450 struct v4l2_fmtdesc *format,
451 gint *min_w, gint *max_w,
452 gint *min_h, gint *max_h)
454 struct v4l2_format fmt;
456 GST_LOG_OBJECT (v4l2src, "getting size limits with format " GST_FOURCC_FORMAT,
457 GST_FOURCC_ARGS (format->pixelformat));
459 /* get size delimiters */
460 memset(&fmt, 0, sizeof(fmt));
461 fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
462 fmt.fmt.pix.width = 0;
463 fmt.fmt.pix.height = 0;
464 fmt.fmt.pix.pixelformat = format->pixelformat;
465 fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
466 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd,
467 VIDIOC_TRY_FMT, &fmt) < 0) {
472 *min_w = fmt.fmt.pix.width;
474 *min_h = fmt.fmt.pix.height;
475 GST_LOG_OBJECT (v4l2src, "got min size %dx%d", fmt.fmt.pix.width, fmt.fmt.pix.height);
477 fmt.fmt.pix.width = G_MAXINT;
478 fmt.fmt.pix.height = 576;
479 if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd,
480 VIDIOC_TRY_FMT, &fmt) < 0) {
485 *max_w = fmt.fmt.pix.width;
487 *max_h = fmt.fmt.pix.height;
488 GST_LOG_OBJECT (v4l2src, "got max size %dx%d", fmt.fmt.pix.width, fmt.fmt.pix.height);