v4l2: add interlaced support

sys/v4l2/gstv4l2object.c

@@ -1361,8 +1361,8 @@ gst_v4l2_object_get_all_caps (void)
  */
 gboolean
 gst_v4l2_object_get_caps_info (GstV4l2Object * v4l2object, GstCaps * caps,
-    struct v4l2_fmtdesc ** format, gint * w, gint * h, guint * fps_n,
-    guint * fps_d, guint * size)
+    struct v4l2_fmtdesc ** format, gint * w, gint * h,
+    gboolean * interlaced, guint * fps_n, guint * fps_d, guint * size)
 {
   GstStructure *structure;
   const GValue *framerate;
@@ -1391,6 +1391,9 @@ gst_v4l2_object_get_caps_info (GstV4l2Object * v4l2object, GstCaps * caps,
   if (!gst_structure_get_int (structure, "height", h))
     return FALSE;
 
+  if (!gst_structure_get_boolean (structure, "interlaced", interlaced))
+    *interlaced = FALSE;
+
   framerate = gst_structure_get_value (structure, "framerate");
   if (!framerate)
     return FALSE;
@@ -1987,15 +1990,15 @@ gst_v4l2_object_get_nearest_size (GstV4l2Object * v4l2object,
   fmt.fmt.pix.width = *width;
   fmt.fmt.pix.height = *height;
   fmt.fmt.pix.pixelformat = pixelformat;
-  fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
+  fmt.fmt.pix.field = V4L2_FIELD_NONE;
 
   r = v4l2_ioctl (fd, VIDIOC_TRY_FMT, &fmt);
   if (r < 0 && errno == EINVAL) {
-    /* try again with progressive video */
+    /* try again with interlaced video */
     fmt.fmt.pix.width = *width;
     fmt.fmt.pix.height = *height;
     fmt.fmt.pix.pixelformat = pixelformat;
-    fmt.fmt.pix.field = V4L2_FIELD_NONE;
+    fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;
     r = v4l2_ioctl (fd, VIDIOC_TRY_FMT, &fmt);
   }
 
@@ -2037,6 +2040,7 @@ gst_v4l2_object_get_nearest_size (GstV4l2Object * v4l2object,
   *height = fmt.fmt.pix.height;
 
   switch (fmt.fmt.pix.field) {
+    case V4L2_FIELD_ANY:
     case V4L2_FIELD_NONE:
       *interlaced = FALSE;
       break;
@@ -2058,10 +2062,22 @@ gst_v4l2_object_get_nearest_size (GstV4l2Object * v4l2object,
 
 gboolean
 gst_v4l2_object_set_format (GstV4l2Object * v4l2object, guint32 pixelformat,
-    guint32 width, guint32 height)
+    guint32 width, guint32 height, gboolean interlaced)
 {
   gint fd = v4l2object->video_fd;
   struct v4l2_format format;
+  enum v4l2_field field;
+
+  if (interlaced) {
+    GST_DEBUG_OBJECT (v4l2object->element, "interlaced video");
+    /* ideally we would differentiate between types of interlaced video
+     * but there is not sufficient information in the caps..
+     */
+    field = V4L2_FIELD_SEQ_TB;
+  } else {
+    GST_DEBUG_OBJECT (v4l2object->element, "progressive video");
+    field = V4L2_FIELD_NONE;
+  }
 
   GST_DEBUG_OBJECT (v4l2object->element, "Setting format to %dx%d, format "
       "%" GST_FOURCC_FORMAT, width, height, GST_FOURCC_ARGS (pixelformat));
@@ -2081,7 +2097,8 @@ gst_v4l2_object_set_format (GstV4l2Object * v4l2object, guint32 pixelformat,
   if (format.type == v4l2object->type &&
       format.fmt.pix.width == width &&
       format.fmt.pix.height == height &&
-      format.fmt.pix.pixelformat == pixelformat) {
+      format.fmt.pix.pixelformat == pixelformat &&
+      format.fmt.pix.field == field) {
     /* Nothing to do. We want to succeed immediately
      * here because setting the same format back
      * can still fail due to EBUSY. By short-circuiting
@@ -2098,24 +2115,9 @@ gst_v4l2_object_set_format (GstV4l2Object * v4l2object, guint32 pixelformat,
   format.fmt.pix.width = width;
   format.fmt.pix.height = height;
   format.fmt.pix.pixelformat = pixelformat;
-  /* FIXME: request whole frames; need to use gstreamer interlace support
-   * (INTERLACED mode returns frames where the fields have already been
-   *  combined, there are other modes for requesting fields individually) */
-  format.fmt.pix.field = V4L2_FIELD_INTERLACED;
+  format.fmt.pix.field = field;
 
   if (v4l2_ioctl (fd, VIDIOC_S_FMT, &format) < 0) {
-    /* we might also get EBUSY here */
-    if (errno != EINVAL)
-      goto set_fmt_failed;
-
-    GST_DEBUG_OBJECT (v4l2object->element, "trying again...");
-
-    /* try again with progressive video */
-    format.fmt.pix.width = width;
-    format.fmt.pix.height = height;
-    format.fmt.pix.pixelformat = pixelformat;
-    format.fmt.pix.field = V4L2_FIELD_NONE;
-    if (v4l2_ioctl (fd, VIDIOC_S_FMT, &format) < 0)
     goto set_fmt_failed;
   }
 

sys/v4l2/gstv4l2object.h

@@ -181,7 +181,7 @@ GstCaps*      gst_v4l2_object_probe_caps_for_format (GstV4l2Object *v4l2object,
 
 gboolean      gst_v4l2_object_get_caps_info (GstV4l2Object *v4l2object, GstCaps *caps,
                                              struct v4l2_fmtdesc **format, gint *w, gint *h,
-                                             guint *fps_n, guint *fps_d, guint *size);
+                                             gboolean * interlaced, guint *fps_n, guint *fps_d, guint *size);
 
 
 GSList*       gst_v4l2_object_get_format_list  (GstV4l2Object *v4l2object);
@@ -190,7 +190,7 @@ GstCaps*      gst_v4l2_object_get_all_caps (void);
 
 GstStructure* gst_v4l2_object_v4l2fourcc_to_structure (guint32 fourcc);
 
-gboolean      gst_v4l2_object_set_format (GstV4l2Object *v4l2object, guint32 pixelformat, guint32 width, guint32 height);
+gboolean      gst_v4l2_object_set_format (GstV4l2Object *v4l2object, guint32 pixelformat, guint32 width, guint32 height, gboolean interlaced);
 
 gboolean      gst_v4l2_object_start_streaming (GstV4l2Object *v4l2object);
 gboolean      gst_v4l2_object_stop_streaming (GstV4l2Object *v4l2object);

sys/v4l2/gstv4l2sink.c

@@ -689,6 +689,7 @@ gst_v4l2sink_set_caps (GstBaseSink * bsink, GstCaps * caps)
 {
   GstV4l2Sink *v4l2sink = GST_V4L2SINK (bsink);
   gint w = 0, h = 0;
+  gboolean interlaced;
   struct v4l2_fmtdesc *format;
   guint fps_n, fps_d;
   guint size;
@@ -724,7 +725,7 @@ gst_v4l2sink_set_caps (GstBaseSink * bsink, GstCaps * caps)
 
   /* we want our own v4l2 type of fourcc codes */
   if (!gst_v4l2_object_get_caps_info (v4l2sink->v4l2object, caps,
-          &format, &w, &h, &fps_n, &fps_d, &size)) {
+          &format, &w, &h, &interlaced, &fps_n, &fps_d, &size)) {
     GST_DEBUG_OBJECT (v4l2sink, "can't get capture format from caps %p", caps);
     return FALSE;
   }
@@ -734,8 +735,8 @@ gst_v4l2sink_set_caps (GstBaseSink * bsink, GstCaps * caps)
     return FALSE;
   }
 
-  if (!gst_v4l2_object_set_format (v4l2sink->v4l2object, format->pixelformat, w,
-          h)) {
+  if (!gst_v4l2_object_set_format (v4l2sink->v4l2object, format->pixelformat,
+          w, h, interlaced)) {
     /* error already posted */
     return FALSE;
   }

sys/v4l2/gstv4l2src.c

@@ -611,6 +611,7 @@ gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps)
 {
   GstV4l2Src *v4l2src;
   gint w = 0, h = 0;
+  gboolean interlaced;
   struct v4l2_fmtdesc *format;
   guint fps_n, fps_d;
   guint size;
@@ -632,7 +633,7 @@ gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps)
 
   /* we want our own v4l2 type of fourcc codes */
   if (!gst_v4l2_object_get_caps_info (v4l2src->v4l2object, caps, &format, &w,
-          &h, &fps_n, &fps_d, &size)) {
+          &h, &interlaced, &fps_n, &fps_d, &size)) {
     GST_INFO_OBJECT (v4l2src,
         "can't get capture format from caps %" GST_PTR_FORMAT, caps);
     return FALSE;
@@ -641,8 +642,8 @@ gst_v4l2src_set_caps (GstBaseSrc * src, GstCaps * caps)
   GST_DEBUG_OBJECT (v4l2src, "trying to set_capture %dx%d at %d/%d fps, "
       "format %s", w, h, fps_n, fps_d, format->description);
 
-  if (!gst_v4l2src_set_capture (v4l2src, format->pixelformat, w, h, fps_n,
-          fps_d))
+  if (!gst_v4l2src_set_capture (v4l2src, format->pixelformat, w, h,
+          interlaced, fps_n, fps_d))
     /* error already posted */
     return FALSE;
 

sys/v4l2/v4l2src_calls.c

@@ -214,7 +214,8 @@ too_many_trials:
  ******************************************************/
 gboolean
 gst_v4l2src_set_capture (GstV4l2Src * v4l2src, guint32 pixelformat,
-    guint32 width, guint32 height, guint fps_n, guint fps_d)
+    guint32 width, guint32 height, gboolean interlaced,
+    guint fps_n, guint fps_d)
 {
   gint fd = v4l2src->v4l2object->video_fd;
   struct v4l2_streamparm stream;
@@ -223,7 +224,7 @@ gst_v4l2src_set_capture (GstV4l2Src * v4l2src, guint32 pixelformat,
     return TRUE;
 
   if (!gst_v4l2_object_set_format (v4l2src->v4l2object, pixelformat, width,
-          height)) {
+          height, interlaced)) {
     /* error already reported */
     return FALSE;
   }

sys/v4l2/v4l2src_calls.h

@@ -31,6 +31,7 @@ gboolean   gst_v4l2src_get_capture       (GstV4l2Src * v4l2src);
 gboolean   gst_v4l2src_set_capture       (GstV4l2Src * v4l2src,
                                           guint32 pixelformat,
                                           guint32 width, guint32 height,
+                                          gboolean interlaced,
                                           guint32 fps_n, guint32 fps_d);
 
 gboolean   gst_v4l2src_capture_init      (GstV4l2Src * v4l2src, GstCaps *caps);