gstreamer/sys/v4l2/gstv4l2src.c
Wim Taymans 9f4cf3be58 v4l2: Move configuration of framerate to _set_format
Move the configuration of the framerate to where we set the other format
parameters.
Remove hack to check if the device is active.
Store streamparm in the device info.
Use some macros to access the current device configuration.
Remove some duplicate fields in src and sink and use the device configuration
instead.
2011-07-13 11:19:28 +02:00

969 lines
27 KiB
C

/* GStreamer
*
* Copyright (C) 2001-2002 Ronald Bultje <rbultje@ronald.bitfreak.net>
* 2006 Edgard Lima <edgard.lima@indt.org.br>
*
* gstv4l2src.c: Video4Linux2 source element
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/**
* SECTION:element-v4l2src
*
* v4l2src can be used to capture video from v4l2 devices, like webcams and tv
* cards.
*
* <refsect2>
* <title>Example launch lines</title>
* |[
* gst-launch v4l2src ! xvimagesink
* ]| This pipeline shows the video captured from /dev/video0 tv card and for
* webcams.
* |[
* gst-launch v4l2src ! jpegdec ! xvimagesink
* ]| This pipeline shows the video captured from a webcam that delivers jpeg
* images.
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#undef HAVE_XVIDEO
#include <string.h>
#include <sys/time.h>
#include "v4l2src_calls.h"
#include <unistd.h>
#include "gstv4l2colorbalance.h"
#include "gstv4l2tuner.h"
#ifdef HAVE_XVIDEO
#include "gstv4l2xoverlay.h"
#endif
#include "gstv4l2vidorient.h"
#include "gst/gst-i18n-plugin.h"
GST_DEBUG_CATEGORY (v4l2src_debug);
#define GST_CAT_DEFAULT v4l2src_debug
#define PROP_DEF_QUEUE_SIZE 2
#define PROP_DEF_ALWAYS_COPY TRUE
#define PROP_DEF_DECIMATE 1
#define DEFAULT_PROP_DEVICE "/dev/video0"
enum
{
PROP_0,
V4L2_STD_OBJECT_PROPS,
PROP_QUEUE_SIZE,
PROP_ALWAYS_COPY,
PROP_DECIMATE
};
GST_IMPLEMENT_V4L2_PROBE_METHODS (GstV4l2SrcClass, gst_v4l2src);
GST_IMPLEMENT_V4L2_COLOR_BALANCE_METHODS (GstV4l2Src, gst_v4l2src);
GST_IMPLEMENT_V4L2_TUNER_METHODS (GstV4l2Src, gst_v4l2src);
#ifdef HAVE_XVIDEO
GST_IMPLEMENT_V4L2_XOVERLAY_METHODS (GstV4l2Src, gst_v4l2src);
#endif
GST_IMPLEMENT_V4L2_VIDORIENT_METHODS (GstV4l2Src, gst_v4l2src);
static void gst_v4l2src_uri_handler_init (gpointer g_iface,
gpointer iface_data);
#define gst_v4l2src_parent_class parent_class
G_DEFINE_TYPE_WITH_CODE (GstV4l2Src, gst_v4l2src, GST_TYPE_PUSH_SRC,
G_IMPLEMENT_INTERFACE (GST_TYPE_URI_HANDLER, gst_v4l2src_uri_handler_init);
G_IMPLEMENT_INTERFACE (GST_TYPE_TUNER, gst_v4l2src_tuner_interface_init);
#ifdef HAVE_XVIDEO
/* FIXME: does GstXOverlay for v4l2src make sense in a GStreamer context? */
G_IMPLEMENT_INTERFACE (GST_TYPE_X_OVERLAY,
gst_v4l2src_xoverlay_interface_init);
#endif
G_IMPLEMENT_INTERFACE (GST_TYPE_COLOR_BALANCE,
gst_v4l2src_color_balance_interface_init);
G_IMPLEMENT_INTERFACE (GST_TYPE_VIDEO_ORIENTATION,
gst_v4l2src_video_orientation_interface_init);
G_IMPLEMENT_INTERFACE (GST_TYPE_PROPERTY_PROBE,
gst_v4l2src_property_probe_interface_init));
static void gst_v4l2src_dispose (GObject * object);
static void gst_v4l2src_finalize (GstV4l2Src * v4l2src);
/* element methods */
static GstStateChangeReturn gst_v4l2src_change_state (GstElement * element,
GstStateChange transition);
/* basesrc methods */
static gboolean gst_v4l2src_start (GstBaseSrc * src);
static gboolean gst_v4l2src_unlock (GstBaseSrc * src);
static gboolean gst_v4l2src_unlock_stop (GstBaseSrc * src);
static gboolean gst_v4l2src_stop (GstBaseSrc * src);
static gboolean gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps);
static GstCaps *gst_v4l2src_get_caps (GstBaseSrc * src, GstCaps * filter);
static gboolean gst_v4l2src_query (GstBaseSrc * bsrc, GstQuery * query);
static GstFlowReturn gst_v4l2src_create (GstPushSrc * src, GstBuffer ** out);
static void gst_v4l2src_fixate (GstBaseSrc * basesrc, GstCaps * caps);
static gboolean gst_v4l2src_negotiate (GstBaseSrc * basesrc);
static void gst_v4l2src_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_v4l2src_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
/* get_frame io methods */
static GstFlowReturn
gst_v4l2src_get_read (GstV4l2Src * v4l2src, GstBuffer ** buf);
static GstFlowReturn
gst_v4l2src_get_mmap (GstV4l2Src * v4l2src, GstBuffer ** buf);
static void
gst_v4l2src_class_init (GstV4l2SrcClass * klass)
{
GObjectClass *gobject_class;
GstElementClass *element_class;
GstBaseSrcClass *basesrc_class;
GstPushSrcClass *pushsrc_class;
gobject_class = G_OBJECT_CLASS (klass);
element_class = GST_ELEMENT_CLASS (klass);
basesrc_class = GST_BASE_SRC_CLASS (klass);
pushsrc_class = GST_PUSH_SRC_CLASS (klass);
gobject_class->dispose = gst_v4l2src_dispose;
gobject_class->finalize = (GObjectFinalizeFunc) gst_v4l2src_finalize;
gobject_class->set_property = gst_v4l2src_set_property;
gobject_class->get_property = gst_v4l2src_get_property;
element_class->change_state = gst_v4l2src_change_state;
gst_v4l2_object_install_properties_helper (gobject_class,
DEFAULT_PROP_DEVICE);
g_object_class_install_property (gobject_class, PROP_QUEUE_SIZE,
g_param_spec_uint ("queue-size", "Queue size",
"Number of buffers to be enqueud in the driver in streaming mode",
GST_V4L2_MIN_BUFFERS, GST_V4L2_MAX_BUFFERS, PROP_DEF_QUEUE_SIZE,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_ALWAYS_COPY,
g_param_spec_boolean ("always-copy", "Always Copy",
"If the buffer will or not be used directly from mmap",
PROP_DEF_ALWAYS_COPY, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
/**
* GstV4l2Src:decimate
*
* Only use every nth frame
*
* Since: 0.10.26
*/
g_object_class_install_property (gobject_class, PROP_DECIMATE,
g_param_spec_int ("decimate", "Decimate",
"Only use every nth frame", 1, G_MAXINT,
PROP_DEF_DECIMATE, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
gst_element_class_set_details_simple (element_class,
"Video (video4linux2) Source", "Source/Video",
"Reads frames from a Video4Linux2 device",
"Edgard Lima <edgard.lima@indt.org.br>, "
"Stefan Kost <ensonic@users.sf.net>");
gst_element_class_add_pad_template
(element_class,
gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS,
gst_v4l2_object_get_all_caps ()));
basesrc_class->get_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_get_caps);
basesrc_class->set_caps = GST_DEBUG_FUNCPTR (gst_v4l2src_set_caps);
basesrc_class->start = GST_DEBUG_FUNCPTR (gst_v4l2src_start);
basesrc_class->unlock = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock);
basesrc_class->unlock_stop = GST_DEBUG_FUNCPTR (gst_v4l2src_unlock_stop);
basesrc_class->stop = GST_DEBUG_FUNCPTR (gst_v4l2src_stop);
basesrc_class->query = GST_DEBUG_FUNCPTR (gst_v4l2src_query);
basesrc_class->fixate = GST_DEBUG_FUNCPTR (gst_v4l2src_fixate);
basesrc_class->negotiate = GST_DEBUG_FUNCPTR (gst_v4l2src_negotiate);
pushsrc_class->create = GST_DEBUG_FUNCPTR (gst_v4l2src_create);
klass->v4l2_class_devices = NULL;
GST_DEBUG_CATEGORY_INIT (v4l2src_debug, "v4l2src", 0, "V4L2 source element");
}
static void
gst_v4l2src_init (GstV4l2Src * v4l2src)
{
/* fixme: give an update_fps_function */
v4l2src->v4l2object = gst_v4l2_object_new (GST_ELEMENT (v4l2src),
V4L2_BUF_TYPE_VIDEO_CAPTURE, DEFAULT_PROP_DEVICE,
gst_v4l2_get_input, gst_v4l2_set_input, NULL);
/* number of buffers requested */
v4l2src->num_buffers = PROP_DEF_QUEUE_SIZE;
v4l2src->always_copy = PROP_DEF_ALWAYS_COPY;
v4l2src->decimate = PROP_DEF_DECIMATE;
v4l2src->is_capturing = FALSE;
gst_base_src_set_format (GST_BASE_SRC (v4l2src), GST_FORMAT_TIME);
gst_base_src_set_live (GST_BASE_SRC (v4l2src), TRUE);
}
static void
gst_v4l2src_dispose (GObject * object)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (object);
if (v4l2src->probed_caps) {
gst_caps_unref (v4l2src->probed_caps);
}
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_v4l2src_finalize (GstV4l2Src * v4l2src)
{
gst_v4l2_object_destroy (v4l2src->v4l2object);
G_OBJECT_CLASS (parent_class)->finalize ((GObject *) (v4l2src));
}
static void
gst_v4l2src_set_property (GObject * object,
guint prop_id, const GValue * value, GParamSpec * pspec)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (object);
if (!gst_v4l2_object_set_property_helper (v4l2src->v4l2object,
prop_id, value, pspec)) {
switch (prop_id) {
case PROP_QUEUE_SIZE:
v4l2src->num_buffers = g_value_get_uint (value);
break;
case PROP_ALWAYS_COPY:
v4l2src->always_copy = g_value_get_boolean (value);
break;
case PROP_DECIMATE:
v4l2src->decimate = g_value_get_int (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
}
static void
gst_v4l2src_get_property (GObject * object,
guint prop_id, GValue * value, GParamSpec * pspec)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (object);
if (!gst_v4l2_object_get_property_helper (v4l2src->v4l2object,
prop_id, value, pspec)) {
switch (prop_id) {
case PROP_QUEUE_SIZE:
g_value_set_uint (value, v4l2src->num_buffers);
break;
case PROP_ALWAYS_COPY:
g_value_set_boolean (value, v4l2src->always_copy);
break;
case PROP_DECIMATE:
g_value_set_int (value, v4l2src->decimate);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
}
}
/* this function is a bit of a last resort */
static void
gst_v4l2src_fixate (GstBaseSrc * basesrc, GstCaps * caps)
{
GstStructure *structure;
gint i;
GST_DEBUG_OBJECT (basesrc, "fixating caps %" GST_PTR_FORMAT, caps);
for (i = 0; i < gst_caps_get_size (caps); ++i) {
const GValue *v;
structure = gst_caps_get_structure (caps, i);
/* We are fixating to a resonable 320x200 resolution
and the maximum framerate resolution for that size */
gst_structure_fixate_field_nearest_int (structure, "width", 320);
gst_structure_fixate_field_nearest_int (structure, "height", 200);
gst_structure_fixate_field_nearest_fraction (structure, "framerate",
G_MAXINT, 1);
v = gst_structure_get_value (structure, "format");
if (v && G_VALUE_TYPE (v) != G_TYPE_STRING) {
const gchar *format;
g_return_if_fail (G_VALUE_TYPE (v) == GST_TYPE_LIST);
format = g_value_get_string (gst_value_list_get_value (v, 0));
gst_structure_set (structure, "format", G_TYPE_STRING, format, NULL);
}
}
GST_DEBUG_OBJECT (basesrc, "fixated caps %" GST_PTR_FORMAT, caps);
}
static gboolean
gst_v4l2src_negotiate (GstBaseSrc * basesrc)
{
GstCaps *thiscaps;
GstCaps *caps = NULL;
GstCaps *peercaps = NULL;
gboolean result = FALSE;
/* first see what is possible on our source pad */
thiscaps = gst_pad_get_caps (GST_BASE_SRC_PAD (basesrc), NULL);
GST_DEBUG_OBJECT (basesrc, "caps of src: %" GST_PTR_FORMAT, thiscaps);
LOG_CAPS (basesrc, thiscaps);
/* nothing or anything is allowed, we're done */
if (thiscaps == NULL || gst_caps_is_any (thiscaps))
goto no_nego_needed;
/* get the peer caps */
peercaps = gst_pad_peer_get_caps (GST_BASE_SRC_PAD (basesrc), thiscaps);
GST_DEBUG_OBJECT (basesrc, "caps of peer: %" GST_PTR_FORMAT, peercaps);
LOG_CAPS (basesrc, peercaps);
if (peercaps && !gst_caps_is_any (peercaps)) {
GstCaps *icaps = NULL;
int i;
/* Prefer the first caps we are compatible with that the peer proposed */
for (i = 0; i < gst_caps_get_size (peercaps); i++) {
/* get intersection */
GstCaps *ipcaps = gst_caps_copy_nth (peercaps, i);
GST_DEBUG_OBJECT (basesrc, "peer: %" GST_PTR_FORMAT, ipcaps);
LOG_CAPS (basesrc, ipcaps);
icaps = gst_caps_intersect (thiscaps, ipcaps);
gst_caps_unref (ipcaps);
if (!gst_caps_is_empty (icaps))
break;
gst_caps_unref (icaps);
icaps = NULL;
}
GST_DEBUG_OBJECT (basesrc, "intersect: %" GST_PTR_FORMAT, icaps);
LOG_CAPS (basesrc, icaps);
if (icaps) {
/* If there are multiple intersections pick the one with the smallest
* resolution strictly bigger then the first peer caps */
if (gst_caps_get_size (icaps) > 1) {
GstStructure *s = gst_caps_get_structure (peercaps, 0);
int best = 0;
int twidth, theight;
int width = G_MAXINT, height = G_MAXINT;
if (gst_structure_get_int (s, "width", &twidth)
&& gst_structure_get_int (s, "height", &theight)) {
/* Walk the structure backwards to get the first entry of the
* smallest resolution bigger (or equal to) the preferred resolution)
*/
for (i = gst_caps_get_size (icaps) - 1; i >= 0; i--) {
GstStructure *is = gst_caps_get_structure (icaps, i);
int w, h;
if (gst_structure_get_int (is, "width", &w)
&& gst_structure_get_int (is, "height", &h)) {
if (w >= twidth && w <= width && h >= theight && h <= height) {
width = w;
height = h;
best = i;
}
}
}
}
caps = gst_caps_copy_nth (icaps, best);
gst_caps_unref (icaps);
} else {
caps = icaps;
}
}
gst_caps_unref (thiscaps);
gst_caps_unref (peercaps);
} else {
/* no peer or peer have ANY caps, work with our own caps then */
caps = thiscaps;
}
if (caps) {
caps = gst_caps_make_writable (caps);
gst_caps_truncate (caps);
/* now fixate */
if (!gst_caps_is_empty (caps)) {
gst_pad_fixate_caps (GST_BASE_SRC_PAD (basesrc), caps);
GST_DEBUG_OBJECT (basesrc, "fixated to: %" GST_PTR_FORMAT, caps);
LOG_CAPS (basesrc, caps);
if (gst_caps_is_any (caps)) {
/* hmm, still anything, so element can do anything and
* nego is not needed */
result = TRUE;
} else if (gst_caps_is_fixed (caps)) {
/* yay, fixed caps, use those then */
gst_pad_push_event (GST_BASE_SRC_PAD (basesrc),
gst_event_new_caps (caps));
result = gst_v4l2src_set_caps (basesrc, caps);
}
}
gst_caps_unref (caps);
}
return result;
no_nego_needed:
{
GST_DEBUG_OBJECT (basesrc, "no negotiation needed");
if (thiscaps)
gst_caps_unref (thiscaps);
return TRUE;
}
}
static GstCaps *
gst_v4l2src_get_caps (GstBaseSrc * src, GstCaps * filter)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
GstCaps *ret;
GSList *walk;
GSList *formats;
if (!GST_V4L2_IS_OPEN (v4l2src->v4l2object)) {
/* FIXME: copy? */
return
gst_caps_copy (gst_pad_get_pad_template_caps (GST_BASE_SRC_PAD
(v4l2src)));
}
if (v4l2src->probed_caps)
return gst_caps_ref (v4l2src->probed_caps);
formats = gst_v4l2_object_get_format_list (v4l2src->v4l2object);
ret = gst_caps_new_empty ();
for (walk = formats; walk; walk = walk->next) {
struct v4l2_fmtdesc *format;
GstStructure *template;
format = (struct v4l2_fmtdesc *) walk->data;
template = gst_v4l2_object_v4l2fourcc_to_structure (format->pixelformat);
if (template) {
GstCaps *tmp;
tmp =
gst_v4l2_object_probe_caps_for_format (v4l2src->v4l2object,
format->pixelformat, template);
if (tmp)
gst_caps_append (ret, tmp);
gst_structure_free (template);
} else {
GST_DEBUG_OBJECT (v4l2src, "unknown format %u", format->pixelformat);
}
}
v4l2src->probed_caps = gst_caps_ref (ret);
GST_INFO_OBJECT (v4l2src, "probed caps: %" GST_PTR_FORMAT, ret);
return ret;
}
static gboolean
gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps)
{
GstV4l2Src *v4l2src;
v4l2src = GST_V4L2SRC (src);
/* if we're not open, punt -- we'll get setcaps'd later via negotiate */
if (!GST_V4L2_IS_OPEN (v4l2src->v4l2object))
return FALSE;
/* make sure we stop capturing and dealloc buffers */
if (GST_V4L2_IS_ACTIVE (v4l2src->v4l2object)) {
/* both will throw an element-error on failure */
if (!gst_v4l2src_capture_stop (v4l2src))
return FALSE;
if (!gst_v4l2src_capture_deinit (v4l2src))
return FALSE;
}
if (!gst_v4l2_object_set_format (v4l2src->v4l2object, caps))
/* error already posted */
return FALSE;
if (!gst_v4l2src_capture_init (v4l2src))
return FALSE;
if (v4l2src->use_mmap) {
v4l2src->get_frame = gst_v4l2src_get_mmap;
} else {
v4l2src->get_frame = gst_v4l2src_get_read;
}
if (!gst_v4l2src_capture_start (v4l2src))
return FALSE;
/* now store the expected output size */
v4l2src->frame_byte_size = v4l2src->v4l2object->size;
return TRUE;
}
static gboolean
gst_v4l2src_query (GstBaseSrc * bsrc, GstQuery * query)
{
GstV4l2Src *src;
gboolean res = FALSE;
src = GST_V4L2SRC (bsrc);
switch (GST_QUERY_TYPE (query)) {
case GST_QUERY_LATENCY:{
GstClockTime min_latency, max_latency;
guint32 fps_n, fps_d;
/* device must be open */
if (!GST_V4L2_IS_OPEN (src->v4l2object)) {
GST_WARNING_OBJECT (src,
"Can't give latency since device isn't open !");
goto done;
}
fps_n = GST_V4L2_FPS_N (src->v4l2object);
fps_d = GST_V4L2_FPS_D (src->v4l2object);
/* we must have a framerate */
if (fps_n <= 0 || fps_d <= 0) {
GST_WARNING_OBJECT (src,
"Can't give latency since framerate isn't fixated !");
goto done;
}
/* min latency is the time to capture one frame */
min_latency = gst_util_uint64_scale_int (GST_SECOND, fps_d, fps_n);
/* max latency is total duration of the frame buffer */
max_latency = src->num_buffers * min_latency;
GST_DEBUG_OBJECT (bsrc,
"report latency min %" GST_TIME_FORMAT " max %" GST_TIME_FORMAT,
GST_TIME_ARGS (min_latency), GST_TIME_ARGS (max_latency));
/* we are always live, the min latency is 1 frame and the max latency is
* the complete buffer of frames. */
gst_query_set_latency (query, TRUE, min_latency, max_latency);
res = TRUE;
break;
}
default:
res = GST_BASE_SRC_CLASS (parent_class)->query (bsrc, query);
break;
}
done:
return res;
}
/* start and stop are not symmetric -- start will open the device, but not start
* capture. it's setcaps that will start capture, which is called via basesrc's
* negotiate method. stop will both stop capture and close the device.
*/
static gboolean
gst_v4l2src_start (GstBaseSrc * src)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
v4l2src->offset = 0;
/* activate settings for first frame */
v4l2src->ctrl_time = 0;
gst_object_sync_values (G_OBJECT (src), v4l2src->ctrl_time);
return TRUE;
}
static gboolean
gst_v4l2src_unlock (GstBaseSrc * src)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
GST_LOG_OBJECT (src, "Flushing");
gst_poll_set_flushing (v4l2src->v4l2object->poll, TRUE);
return TRUE;
}
static gboolean
gst_v4l2src_unlock_stop (GstBaseSrc * src)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
GST_LOG_OBJECT (src, "No longer flushing");
gst_poll_set_flushing (v4l2src->v4l2object->poll, FALSE);
return TRUE;
}
static gboolean
gst_v4l2src_stop (GstBaseSrc * src)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
if (GST_V4L2_IS_ACTIVE (v4l2src->v4l2object)) {
if (!gst_v4l2src_capture_stop (v4l2src))
return FALSE;
if (!gst_v4l2src_capture_deinit (v4l2src))
return FALSE;
}
return TRUE;
}
static GstStateChangeReturn
gst_v4l2src_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
GstV4l2Src *v4l2src = GST_V4L2SRC (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
/* open the device */
if (!gst_v4l2_object_start (v4l2src->v4l2object))
return GST_STATE_CHANGE_FAILURE;
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_READY_TO_NULL:
/* close the device */
if (!gst_v4l2_object_stop (v4l2src->v4l2object))
return GST_STATE_CHANGE_FAILURE;
if (v4l2src->probed_caps) {
gst_caps_unref (v4l2src->probed_caps);
v4l2src->probed_caps = NULL;
}
break;
default:
break;
}
return ret;
}
static GstFlowReturn
gst_v4l2src_get_read (GstV4l2Src * v4l2src, GstBuffer ** buf)
{
GstFlowReturn res;
gint amount;
gint ret;
gpointer data;
gint buffersize;
buffersize = v4l2src->frame_byte_size;
/* In case the size per frame is unknown assume it's a streaming format (e.g.
* mpegts) and grab a reasonable default size instead */
if (buffersize == 0)
buffersize = GST_BASE_SRC (v4l2src)->blocksize;
*buf = gst_buffer_new_and_alloc (buffersize);
data = gst_buffer_map (*buf, NULL, NULL, GST_MAP_WRITE);
do {
ret = gst_poll_wait (v4l2src->v4l2object->poll, GST_CLOCK_TIME_NONE);
if (G_UNLIKELY (ret < 0)) {
if (errno == EBUSY)
goto stopped;
if (errno == ENXIO) {
GST_DEBUG_OBJECT (v4l2src,
"v4l2 device doesn't support polling. Disabling");
v4l2src->v4l2object->can_poll_device = FALSE;
} else {
if (errno != EAGAIN && errno != EINTR)
goto select_error;
}
}
amount = v4l2_read (v4l2src->v4l2object->video_fd, data, buffersize);
if (amount == buffersize) {
break;
} else if (amount == -1) {
if (errno == EAGAIN || errno == EINTR) {
continue;
} else
goto read_error;
} else {
/* short reads can happen if a signal interrupts the read */
continue;
}
} while (TRUE);
gst_buffer_unmap (*buf, data, amount);
/* we set the buffer metadata in gst_v4l2src_create() */
return GST_FLOW_OK;
/* ERRORS */
select_error:
{
GST_ELEMENT_ERROR (v4l2src, RESOURCE, READ, (NULL),
("select error %d: %s (%d)", ret, g_strerror (errno), errno));
res = GST_FLOW_ERROR;
goto cleanup;
}
stopped:
{
GST_DEBUG ("stop called");
res = GST_FLOW_WRONG_STATE;
goto cleanup;
}
read_error:
{
GST_ELEMENT_ERROR (v4l2src, RESOURCE, READ,
(_("Error reading %d bytes from device '%s'."),
buffersize, v4l2src->v4l2object->videodev), GST_ERROR_SYSTEM);
res = GST_FLOW_ERROR;
goto cleanup;
}
cleanup:
{
gst_buffer_unmap (*buf, data, 0);
gst_buffer_unref (*buf);
return res;
}
}
static GstFlowReturn
gst_v4l2src_get_mmap (GstV4l2Src * v4l2src, GstBuffer ** buf)
{
GstBuffer *temp;
GstFlowReturn ret;
guint size;
guint count = 0;
again:
ret = gst_v4l2src_grab_frame (v4l2src, &temp);
if (G_UNLIKELY (ret != GST_FLOW_OK))
goto done;
if (v4l2src->frame_byte_size > 0) {
size = gst_buffer_get_size (temp);
/* if size does not match what we expected, try again */
if (size != v4l2src->frame_byte_size) {
GST_ELEMENT_WARNING (v4l2src, RESOURCE, READ,
(_("Got unexpected frame size of %u instead of %u."),
size, v4l2src->frame_byte_size), (NULL));
gst_buffer_unref (temp);
if (count++ > 50)
goto size_error;
goto again;
}
}
*buf = temp;
done:
return ret;
/* ERRORS */
size_error:
{
GST_ELEMENT_ERROR (v4l2src, RESOURCE, READ,
(_("Error reading %d bytes on device '%s'."),
v4l2src->frame_byte_size, v4l2src->v4l2object->videodev), (NULL));
return GST_FLOW_ERROR;
}
}
static GstFlowReturn
gst_v4l2src_create (GstPushSrc * src, GstBuffer ** buf)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (src);
int i;
GstFlowReturn ret;
if (v4l2src->get_frame == NULL)
goto not_negotiated;
/* decimate, just capture and throw away frames */
for (i = 0; i < v4l2src->decimate - 1; i++) {
ret = v4l2src->get_frame (v4l2src, buf);
if (ret != GST_FLOW_OK) {
return ret;
}
gst_buffer_unref (*buf);
}
ret = v4l2src->get_frame (v4l2src, buf);
/* set buffer metadata */
if (G_LIKELY (ret == GST_FLOW_OK && *buf)) {
GstClock *clock;
GstClockTime timestamp, duration;
GST_BUFFER_OFFSET (*buf) = v4l2src->offset++;
GST_BUFFER_OFFSET_END (*buf) = v4l2src->offset;
/* timestamps, LOCK to get clock and base time. */
/* FIXME: element clock and base_time is rarely changing */
GST_OBJECT_LOCK (v4l2src);
if ((clock = GST_ELEMENT_CLOCK (v4l2src))) {
/* we have a clock, get base time and ref clock */
timestamp = GST_ELEMENT (v4l2src)->base_time;
gst_object_ref (clock);
} else {
/* no clock, can't set timestamps */
timestamp = GST_CLOCK_TIME_NONE;
}
GST_OBJECT_UNLOCK (v4l2src);
duration = v4l2src->v4l2object->duration;
if (G_LIKELY (clock)) {
/* the time now is the time of the clock minus the base time */
timestamp = gst_clock_get_time (clock) - timestamp;
gst_object_unref (clock);
/* if we have a framerate adjust timestamp for frame latency */
if (GST_CLOCK_TIME_IS_VALID (duration)) {
if (timestamp > duration)
timestamp -= duration;
else
timestamp = 0;
}
}
/* activate settings for next frame */
if (GST_CLOCK_TIME_IS_VALID (duration)) {
v4l2src->ctrl_time += duration;
} else {
/* this is not very good (as it should be the next timestamp),
* still good enough for linear fades (as long as it is not -1)
*/
v4l2src->ctrl_time = timestamp;
}
gst_object_sync_values (G_OBJECT (src), v4l2src->ctrl_time);
GST_INFO_OBJECT (src, "sync to %" GST_TIME_FORMAT,
GST_TIME_ARGS (v4l2src->ctrl_time));
/* FIXME: use the timestamp from the buffer itself! */
GST_BUFFER_TIMESTAMP (*buf) = timestamp;
GST_BUFFER_DURATION (*buf) = duration;
}
return ret;
/* ERRORS */
not_negotiated:
{
GST_DEBUG_OBJECT (src, "we are not negotiated");
return GST_FLOW_NOT_NEGOTIATED;
}
}
/* GstURIHandler interface */
static GstURIType
gst_v4l2src_uri_get_type (GType type)
{
return GST_URI_SRC;
}
static gchar **
gst_v4l2src_uri_get_protocols (GType type)
{
static gchar *protocols[] = { (char *) "v4l2", NULL };
return protocols;
}
static const gchar *
gst_v4l2src_uri_get_uri (GstURIHandler * handler)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
if (v4l2src->v4l2object->videodev != NULL) {
gchar uri[256];
/* need to return a const string, but also don't want to leak the generated
* string, so just intern it - there's a limited number of video devices
* after all */
g_snprintf (uri, sizeof (uri), "v4l2://%s", v4l2src->v4l2object->videodev);
return g_intern_string (uri);
}
return "v4l2://";
}
static gboolean
gst_v4l2src_uri_set_uri (GstURIHandler * handler, const gchar * uri)
{
GstV4l2Src *v4l2src = GST_V4L2SRC (handler);
const gchar *device = DEFAULT_PROP_DEVICE;
if (strcmp (uri, "v4l2://") != 0) {
device = uri + 7;
}
g_object_set (v4l2src, "device", device, NULL);
return TRUE;
}
static void
gst_v4l2src_uri_handler_init (gpointer g_iface, gpointer iface_data)
{
GstURIHandlerInterface *iface = (GstURIHandlerInterface *) g_iface;
iface->get_type = gst_v4l2src_uri_get_type;
iface->get_protocols = gst_v4l2src_uri_get_protocols;
iface->get_uri = gst_v4l2src_uri_get_uri;
iface->set_uri = gst_v4l2src_uri_set_uri;
}