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authorRonald S. Bultje <rbultje@ronald.bitfreak.net>2003-05-21 06:33:18 +0000
committerRonald S. Bultje <rbultje@ronald.bitfreak.net>2003-05-21 06:33:18 +0000
commit6588850d7426b792046254d5ddf050c47172e932 (patch)
treebe06b509f6e905de522c5d36dd4b831ef6c98d4b /sys
parent7777638d99477dd6c3548fd958ea83c52fda1b12 (diff)
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Some final fixes for the v4lsrc elements. remove software sync thread (use GST_ELEMENT_THREAD_SUGGESTED instead) make...
Original commit message from CVS: Some final fixes for the v4lsrc elements. * remove software sync thread (use GST_ELEMENT_THREAD_SUGGESTED instead) * make all src elements threadsafe * fix num_buffer argument setting in v4l2src (VIDIOC_S_PARM) * re-add bufsize (RO) for v4lmjpegsrc * fix the A/V sync calculation in all elements (spvf=GST_SECOND/fps, not GST_SECOND*fps) * probably some more crap.... With all this, it actually works quite well. The TODO files describes the next steps in order to make a full-featured video recorder based on these elements and GStreamer (bottom). Making a simple recorder should be fairly easy now, btw.
Diffstat (limited to 'sys')
-rw-r--r--sys/v4l2/gstv4l2src.c27
-rw-r--r--sys/v4l2/gstv4l2src.h11
-rw-r--r--sys/v4l2/v4l2src_calls.c224
-rw-r--r--sys/v4l2/v4l2src_calls.h2
4 files changed, 218 insertions, 46 deletions
diff --git a/sys/v4l2/gstv4l2src.c b/sys/v4l2/gstv4l2src.c
index 92ca2092..a2219606 100644
--- a/sys/v4l2/gstv4l2src.c
+++ b/sys/v4l2/gstv4l2src.c
@@ -195,6 +195,8 @@ gst_v4l2src_class_init (GstV4l2SrcClass *klass)
static void
gst_v4l2src_init (GstV4l2Src *v4l2src)
{
+ GST_FLAG_SET(GST_ELEMENT(v4l2src), GST_ELEMENT_THREAD_SUGGESTED);
+
v4l2src->srcpad = gst_pad_new_from_template(src_template, "src");
gst_element_add_pad(GST_ELEMENT(v4l2src), v4l2src->srcpad);
@@ -257,14 +259,14 @@ gst_v4l2src_get_fps (GstV4l2Src *v4l2src)
/* if that failed ... */
if (!GST_V4L2_IS_OPEN(GST_V4L2ELEMENT(v4l2src)))
- return FALSE;
+ return 0.;
if (!gst_v4l2_get_norm(GST_V4L2ELEMENT(v4l2src), &norm))
- return FALSE;
+ return 0.;
std = ((struct v4l2_standard *) g_list_nth_data(GST_V4L2ELEMENT(v4l2src)->norms, norm));
- fps = std->frameperiod.numerator / std->frameperiod.denominator;
-
+ fps = (1. * std->frameperiod.denominator) / std->frameperiod.numerator;
+
return fps;
}
@@ -643,7 +645,7 @@ gst_v4l2src_srcconnect (GstPad *pad,
gst_caps_get_int(caps, "width", &w);
} else {
int max;
- gst_caps_get_int_range(caps, "width", &w, &max);
+ gst_caps_get_int_range(caps, "width", &max, &w);
}
}
if (gst_caps_has_property(caps, "height")) {
@@ -651,7 +653,7 @@ gst_v4l2src_srcconnect (GstPad *pad,
gst_caps_get_int(caps, "height", &h);
} else {
int max;
- gst_caps_get_int_range(caps, "height", &h, &max);
+ gst_caps_get_int_range(caps, "height", &max, &h);
}
}
@@ -790,14 +792,14 @@ gst_v4l2src_get (GstPad *pad)
* timeframe. This means that if time - begin_time = X sec,
* we want to have written X*fps frames. If we've written
* more - drop, if we've written less - dup... */
- if (v4l2src->handled * fps * GST_SECOND - time >
- 1.5 * fps * GST_SECOND) {
+ if (v4l2src->handled * (GST_SECOND/fps) - time >
+ 1.5 * (GST_SECOND/fps)) {
/* yo dude, we've got too many frames here! Drop! DROP! */
v4l2src->need_writes--; /* -= (v4l2src->handled - (time / fps)); */
g_signal_emit(G_OBJECT(v4l2src),
gst_v4l2src_signals[SIGNAL_FRAME_DROP], 0);
- } else if (v4l2src->handled * fps * GST_SECOND - time <
- -1.5 * fps * GST_SECOND) {
+ } else if (v4l2src->handled * (GST_SECOND/fps) - time <
+ -1.5 * (GST_SECOND/fps)) {
/* this means we're lagging far behind */
v4l2src->need_writes++; /* += ((time / fps) - v4l2src->handled); */
g_signal_emit(G_OBJECT(v4l2src),
@@ -820,7 +822,7 @@ gst_v4l2src_get (GstPad *pad)
v4l2src->use_num_times[num] = 1;
}
- GST_BUFFER_DATA(buf) = GST_V4L2ELEMENT(v4l2src)->buffer[num];
+ GST_BUFFER_DATA(buf) = gst_v4l2src_get_buffer(v4l2src, num);
GST_BUFFER_SIZE(buf) = v4l2src->bufsettings.bytesused;
if (v4l2src->use_fixed_fps)
GST_BUFFER_TIMESTAMP(buf) = v4l2src->handled * GST_SECOND / fps;
@@ -831,6 +833,7 @@ gst_v4l2src_get (GstPad *pad)
v4l2src->handled++;
g_signal_emit(G_OBJECT(v4l2src),
gst_v4l2src_signals[SIGNAL_FRAME_CAPTURE], 0);
+
return buf;
}
@@ -1001,7 +1004,7 @@ gst_v4l2src_buffer_free (GstBufferPool *pool,
return; /* we've already cleaned up ourselves */
for (n=0;n<v4l2src->breq.count;n++)
- if (GST_BUFFER_DATA(buf) == GST_V4L2ELEMENT(v4l2src)->buffer[n]) {
+ if (GST_BUFFER_DATA(buf) == gst_v4l2src_get_buffer(v4l2src, n)) {
v4l2src->use_num_times[n]--;
if (v4l2src->use_num_times[n] <= 0) {
gst_v4l2src_requeue_frame(v4l2src, n);
diff --git a/sys/v4l2/gstv4l2src.h b/sys/v4l2/gstv4l2src.h
index 76fc5ef9..1b4ab095 100644
--- a/sys/v4l2/gstv4l2src.h
+++ b/sys/v4l2/gstv4l2src.h
@@ -52,6 +52,17 @@ struct _GstV4l2Src {
struct v4l2_requestbuffers breq;
struct v4l2_format format;
+ /* num of queued frames and some GThread stuff
+ * to wait if there's not enough */
+ gint8 *frame_queue_state;
+ GMutex *mutex_queue_state;
+ GCond *cond_queue_state;
+ gint num_queued;
+ gint queue_frame;
+
+ /* True if we want to stop */
+ gboolean quit;
+
/* A/V sync... frame counter and internal cache */
gulong handled;
gint last_frame;
diff --git a/sys/v4l2/v4l2src_calls.c b/sys/v4l2/v4l2src_calls.c
index 1f8be1cb..576b6fbe 100644
--- a/sys/v4l2/v4l2src_calls.c
+++ b/sys/v4l2/v4l2src_calls.c
@@ -40,6 +40,12 @@
#define MAP_FAILED ( (caddr_t) -1 )
#endif
+enum {
+ QUEUE_STATE_ERROR = -1,
+ QUEUE_STATE_READY_FOR_QUEUE,
+ QUEUE_STATE_QUEUED,
+ QUEUE_STATE_SYNCED,
+};
/******************************************************
* gst_v4l2src_fill_format_list():
@@ -113,20 +119,28 @@ gst_v4l2src_queue_frame (GstV4l2Src *v4l2src,
{
DEBUG("queueing frame %d", num);
+ if (v4l2src->frame_queue_state[num] != QUEUE_STATE_READY_FOR_QUEUE) {
+ return FALSE;
+ }
+
v4l2src->bufsettings.index = num;
- if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_QBUF, &v4l2src->bufsettings) < 0) {
+ if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd,
+ VIDIOC_QBUF, &v4l2src->bufsettings) < 0) {
gst_element_error(GST_ELEMENT(v4l2src),
"Error queueing buffer %d on device %s: %s",
num, GST_V4L2ELEMENT(v4l2src)->device, g_strerror(errno));
return FALSE;
}
+ v4l2src->frame_queue_state[num] = QUEUE_STATE_QUEUED;
+ v4l2src->num_queued++;
+
return TRUE;
}
/******************************************************
- * gst_v4lsrc_sync_frame():
+ * gst_v4l2src_sync_next_frame():
* sync on a frame for capturing
* return value: TRUE on success, FALSE on error
******************************************************/
@@ -135,15 +149,28 @@ static gboolean
gst_v4l2src_sync_next_frame (GstV4l2Src *v4l2src,
gint *num)
{
- if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_DQBUF, &v4l2src->bufsettings) < 0) {
- gst_element_error(GST_ELEMENT(v4l2src),
- "Error syncing on a buffer on device %s: %s",
- GST_V4L2ELEMENT(v4l2src)->device, g_strerror(errno));
+ if (v4l2src->num_queued <= 0) {
return FALSE;
}
+
+ while (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd,
+ VIDIOC_DQBUF, &v4l2src->bufsettings) < 0) {
+ /* if the sync() got interrupted, we can retry */
+ if (errno != EINTR) {
+ gst_element_error(GST_ELEMENT(v4l2src),
+ "Error syncing on a buffer on device %s: %s",
+ GST_V4L2ELEMENT(v4l2src)->device, g_strerror(errno));
+ return FALSE;
+ }
+ DEBUG("Sync got interrupted");
+ }
+
DEBUG("synced on frame %d", v4l2src->bufsettings.index);
*num = v4l2src->bufsettings.index;
+ v4l2src->frame_queue_state[*num] = QUEUE_STATE_SYNCED;
+ v4l2src->num_queued--;
+
return TRUE;
}
@@ -205,7 +232,8 @@ gst_v4l2src_set_capture (GstV4l2Src *v4l2src,
return FALSE;
}
- return TRUE;
+ /* update internal info */
+ return gst_v4l2src_get_capture(v4l2src);;
}
@@ -220,15 +248,28 @@ gst_v4l2src_capture_init (GstV4l2Src *v4l2src)
{
gint n;
gchar *desc = NULL;
+ struct v4l2_buffer buf;
DEBUG("initting the capture system");
GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
GST_V4L2_CHECK_NOT_ACTIVE(GST_V4L2ELEMENT(v4l2src));
+ /* set num of buffers */
+ if (v4l2src->breq.count > MIN_BUFFERS_QUEUED) {
+ struct v4l2_streamparm p;
+ p.type = v4l2src->format.type;
+
+ /* only if supported */
+ if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd,
+ VIDIOC_G_PARM, &p) == 0) {
+ p.parm.capture.readbuffers = v4l2src->breq.count;
+ ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd,
+ VIDIOC_S_PARM, &p);
+ }
+ }
+
/* request buffer info */
- if (v4l2src->breq.count < MIN_BUFFERS_QUEUED)
- v4l2src->breq.count = MIN_BUFFERS_QUEUED;
v4l2src->breq.type = v4l2src->format.type;
if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_REQBUFS, &v4l2src->breq) < 0) {
gst_element_error(GST_ELEMENT(v4l2src),
@@ -255,24 +296,42 @@ gst_v4l2src_capture_init (GstV4l2Src *v4l2src)
gst_info("Got %d buffers (%s) of size %d KB\n",
v4l2src->breq.count, desc, v4l2src->format.fmt.pix.sizeimage/1024);
- v4l2src->use_num_times = (gint *) malloc(sizeof(gint) * v4l2src->breq.count);
- if (!v4l2src->use_num_times) {
- gst_element_error(GST_ELEMENT(v4l2src),
- "Error creating sync-use-time tracker: %s",
- g_strerror(errno));
- return FALSE;
- }
+ /* keep track of queued buffers */
+ v4l2src->frame_queue_state = (gint8 *)
+ g_malloc(sizeof(gint8) * v4l2src->breq.count);
+
+ /* track how often to use each frame */
+ v4l2src->use_num_times = (gint *)
+ g_malloc(sizeof(gint) * v4l2src->breq.count);
+
+ /* lock for the frame_state */
+ v4l2src->mutex_queue_state = g_mutex_new();
+ v4l2src->cond_queue_state = g_cond_new();
/* Map the buffers */
- GST_V4L2ELEMENT(v4l2src)->buffer = (guint8 **) g_malloc(sizeof(guint8*) * v4l2src->breq.count);
+ GST_V4L2ELEMENT(v4l2src)->buffer = (guint8 **)
+ g_malloc(sizeof(guint8 *) * v4l2src->breq.count);
for (n=0;n<v4l2src->breq.count;n++) {
- GST_V4L2ELEMENT(v4l2src)->buffer[n] = mmap(0, v4l2src->format.fmt.pix.sizeimage,
- PROT_READ|PROT_WRITE, MAP_SHARED, GST_V4L2ELEMENT(v4l2src)->video_fd, v4l2src->format.fmt.pix.sizeimage*n);
+ buf.index = n;
+ buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+ if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd,
+ VIDIOC_QUERYBUF, &buf) < 0) {
+ gst_element_error(GST_ELEMENT(v4l2src),
+ "Failed to get buffer (%d) properties: %s",
+ n, g_strerror(errno));
+ gst_v4l2src_capture_deinit(v4l2src);
+ return FALSE;
+ }
+ GST_V4L2ELEMENT(v4l2src)->buffer[n] = mmap(0,
+ buf.length, PROT_READ|PROT_WRITE, MAP_SHARED,
+ GST_V4L2ELEMENT(v4l2src)->video_fd, buf.m.offset);
if (GST_V4L2ELEMENT(v4l2src)->buffer[n] == MAP_FAILED) {
gst_element_error(GST_ELEMENT(v4l2src),
- "Error mapping video buffer %d on device %s: %s",
- n, GST_V4L2ELEMENT(v4l2src)->device, g_strerror(errno));
+ "Error mapping video buffer (%d) on device %s: %s",
+ n, GST_V4L2ELEMENT(v4l2src)->device,
+ g_strerror(errno));
GST_V4L2ELEMENT(v4l2src)->buffer[n] = NULL;
+ gst_v4l2src_capture_deinit(v4l2src);
return FALSE;
}
}
@@ -296,10 +355,22 @@ gst_v4l2src_capture_start (GstV4l2Src *v4l2src)
GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
- /* queue all buffers, this starts streaming capture */
- for (n=0;n<v4l2src->breq.count;n++)
- if (!gst_v4l2src_queue_frame(v4l2src, n))
+ g_mutex_lock(v4l2src->mutex_queue_state);
+
+ v4l2src->quit = FALSE;
+ v4l2src->num_queued = 0;
+ v4l2src->queue_frame = 0;
+
+ /* set all buffers ready to queue , this starts streaming capture */
+ for (n=0;n<v4l2src->breq.count;n++) {
+ v4l2src->frame_queue_state[n] = QUEUE_STATE_READY_FOR_QUEUE;
+ if (!gst_v4l2src_queue_frame(v4l2src, n)) {
+ g_mutex_unlock(v4l2src->mutex_queue_state);
+ gst_v4l2src_capture_stop(v4l2src);
return FALSE;
+ }
+ }
+
n = 1;
if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_STREAMON, &n) < 0) {
gst_element_error(GST_ELEMENT(v4l2src),
@@ -308,6 +379,8 @@ gst_v4l2src_capture_start (GstV4l2Src *v4l2src)
return FALSE;
}
+ g_mutex_unlock(v4l2src->mutex_queue_state);
+
return TRUE;
}
@@ -327,15 +400,64 @@ gst_v4l2src_grab_frame (GstV4l2Src *v4l2src,
GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
+ g_mutex_lock(v4l2src->mutex_queue_state);
+
+ /* do we have enough frames? */
+ while (v4l2src->num_queued < MIN_BUFFERS_QUEUED ||
+ v4l2src->frame_queue_state[v4l2src->queue_frame] ==
+ QUEUE_STATE_READY_FOR_QUEUE) {
+ while (v4l2src->frame_queue_state[v4l2src->queue_frame] !=
+ QUEUE_STATE_READY_FOR_QUEUE &&
+ !v4l2src->quit) {
+ GST_DEBUG(GST_CAT_PLUGIN_INFO,
+ "Waiting for frames to become available (%d < %d)",
+ v4l2src->num_queued, MIN_BUFFERS_QUEUED);
+ g_cond_wait(v4l2src->cond_queue_state,
+ v4l2src->mutex_queue_state);
+ }
+ if (v4l2src->quit) {
+ g_mutex_unlock(v4l2src->mutex_queue_state);
+ return TRUE; /* it won't get through anyway */
+ }
+ if (!gst_v4l2src_queue_frame(v4l2src, v4l2src->queue_frame)) {
+ g_mutex_unlock(v4l2src->mutex_queue_state);
+ return FALSE;
+ }
+ v4l2src->queue_frame = (v4l2src->queue_frame + 1) % v4l2src->breq.count;
+ }
+
/* syncing on the buffer grabs it */
- if (!gst_v4l2src_sync_next_frame(v4l2src, num))
+ if (!gst_v4l2src_sync_next_frame(v4l2src, num)) {
+ g_mutex_unlock(v4l2src->mutex_queue_state);
return FALSE;
+ }
+
+ g_mutex_unlock(v4l2src->mutex_queue_state);
return TRUE;
}
/******************************************************
+ *
+ ******************************************************/
+
+guint8 *
+gst_v4l2src_get_buffer (GstV4l2Src *v4l2src,
+ gint num)
+{
+ if (!GST_V4L2_IS_ACTIVE(GST_V4L2ELEMENT(v4l2src)) ||
+ !GST_V4L2_IS_OPEN(GST_V4L2ELEMENT(v4l2src)))
+ return NULL;
+
+ if (num < 0 || num >= v4l2src->breq.count)
+ return NULL;
+
+ return GST_V4L2ELEMENT(v4l2src)->buffer[num];
+}
+
+
+/******************************************************
* gst_v4l2src_requeue_frame():
* re-queue a frame after we're done with the buffer
* return value: TRUE on success, FALSE on error
@@ -349,9 +471,23 @@ gst_v4l2src_requeue_frame (GstV4l2Src *v4l2src,
GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
- /* and let's queue the buffer */
- if (!gst_v4l2src_queue_frame(v4l2src, num))
+ /* mark frame as 'ready to requeue' */
+ g_mutex_lock(v4l2src->mutex_queue_state);
+
+ if (v4l2src->frame_queue_state[num] != QUEUE_STATE_SYNCED) {
+ gst_element_error(GST_ELEMENT(v4l2src),
+ "Invalid state %d (expected %d), can't requeue",
+ v4l2src->frame_queue_state[num],
+ QUEUE_STATE_SYNCED);
return FALSE;
+ }
+
+ v4l2src->frame_queue_state[num] = QUEUE_STATE_READY_FOR_QUEUE;
+
+ /* let an optional wait know */
+ g_cond_broadcast(v4l2src->cond_queue_state);
+
+ g_mutex_unlock(v4l2src->mutex_queue_state);
return TRUE;
}
@@ -372,7 +508,10 @@ gst_v4l2src_capture_stop (GstV4l2Src *v4l2src)
GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
- /* we actually need to sync on all queued buffers but not on the non-queued ones */
+ g_mutex_lock(v4l2src->mutex_queue_state);
+
+ /* we actually need to sync on all queued buffers but not
+ * on the non-queued ones */
if (ioctl(GST_V4L2ELEMENT(v4l2src)->video_fd, VIDIOC_STREAMOFF, &n) < 0) {
gst_element_error(GST_ELEMENT(v4l2src),
"Error stopping streaming capture for %s: %s",
@@ -380,6 +519,17 @@ gst_v4l2src_capture_stop (GstV4l2Src *v4l2src)
return FALSE;
}
+ /* make an optional pending wait stop */
+ v4l2src->quit = TRUE;
+ g_cond_broadcast(v4l2src->cond_queue_state);
+
+ /* sync on remaining frames */
+ while (v4l2src->num_queued > 0) {
+ gst_v4l2src_sync_next_frame(v4l2src, &n);
+ }
+
+ g_mutex_unlock(v4l2src->mutex_queue_state);
+
return TRUE;
}
@@ -393,23 +543,29 @@ gst_v4l2src_capture_stop (GstV4l2Src *v4l2src)
gboolean
gst_v4l2src_capture_deinit (GstV4l2Src *v4l2src)
{
- gint n;
-
+ int n;
+
DEBUG("deinitting capture system");
GST_V4L2_CHECK_OPEN(GST_V4L2ELEMENT(v4l2src));
GST_V4L2_CHECK_ACTIVE(GST_V4L2ELEMENT(v4l2src));
/* unmap the buffer */
for (n=0;n<v4l2src->breq.count;n++) {
- if (!GST_V4L2ELEMENT(v4l2src)->buffer[n])
+ if (!GST_V4L2ELEMENT(v4l2src)->buffer[n]) {
break;
- munmap(GST_V4L2ELEMENT(v4l2src)->buffer[n], v4l2src->format.fmt.pix.sizeimage);
+ }
+ munmap(GST_V4L2ELEMENT(v4l2src)->buffer[n],
+ v4l2src->format.fmt.pix.sizeimage);
GST_V4L2ELEMENT(v4l2src)->buffer[n] = NULL;
}
+
+ /* free buffer tracker */
g_free(GST_V4L2ELEMENT(v4l2src)->buffer);
GST_V4L2ELEMENT(v4l2src)->buffer = NULL;
-
- free(v4l2src->use_num_times);
+ g_mutex_free(v4l2src->mutex_queue_state);
+ g_cond_free(v4l2src->cond_queue_state);
+ g_free(v4l2src->frame_queue_state);
+ g_free(v4l2src->use_num_times);
return TRUE;
}
diff --git a/sys/v4l2/v4l2src_calls.h b/sys/v4l2/v4l2src_calls.h
index fceb5755..4332312d 100644
--- a/sys/v4l2/v4l2src_calls.h
+++ b/sys/v4l2/v4l2src_calls.h
@@ -33,6 +33,8 @@ gboolean gst_v4l2src_capture_init (GstV4l2Src *v4l2src);
gboolean gst_v4l2src_capture_start (GstV4l2Src *v4l2src);
gboolean gst_v4l2src_grab_frame (GstV4l2Src *v4l2src,
gint *num);
+guint8 * gst_v4l2src_get_buffer (GstV4l2Src *v4l2src,
+ gint num);
gboolean gst_v4l2src_requeue_frame (GstV4l2Src *v4l2src,
gint num);
gboolean gst_v4l2src_capture_stop (GstV4l2Src *v4l2src);