Merge branch 'h264_h265_force_key_frame' into 'main'

vah26{4, 5}enc: Let FORCE_KEYFRAME be IDR frame rather than just I frame

See merge request gstreamer/gstreamer!6619

subprojects/gst-plugins-bad/sys/va/gstvah264enc.c

@@ -229,6 +229,8 @@ struct _GstVaH264Enc
     guint32 ref_num_list1;
 
     guint num_reorder_frames;
+
+    GstVideoCodecFrame *last_keyframe;
   } gop;
 
   struct
@@ -1546,6 +1548,7 @@ gst_va_h264_enc_reset_state (GstVaBaseEnc * base)
   self->gop.ref_num_list0 = 0;
   self->gop.ref_num_list1 = 0;
   self->gop.num_reorder_frames = 0;
+  self->gop.last_keyframe = NULL;
 
   self->rc.max_bitrate = 0;
   self->rc.target_bitrate = 0;
@@ -1715,58 +1718,101 @@ _push_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame * gst_frame,
 {
   GstVaH264Enc *self = GST_VA_H264_ENC (base);
   GstVaH264EncFrame *frame;
+  gboolean add_cached_key_frame = FALSE;
 
   g_return_val_if_fail (self->gop.cur_frame_index <= self->gop.idr_period,
       FALSE);
 
   if (gst_frame) {
-    /* Begin a new GOP, should have a empty reorder_list. */
-    if (self->gop.cur_frame_index == self->gop.idr_period) {
-      g_assert (g_queue_is_empty (&base->reorder_list));
-      self->gop.cur_frame_index = 0;
-      self->gop.cur_frame_num = 0;
-    }
-
     frame = _enc_frame (gst_frame);
-    frame->poc =
-        ((self->gop.cur_frame_index * 2) % self->gop.max_pic_order_cnt);
 
-    /* TODO: move most this logic onto vabaseenc class  */
-    if (self->gop.cur_frame_index == 0) {
-      g_assert (frame->poc == 0);
-      GST_LOG_OBJECT (self, "system_frame_number: %d, an IDR frame, starts"
-          " a new GOP", gst_frame->system_frame_number);
+    /* Force to insert the key frame inside a GOP, just end the current
+       GOP and start a new one. */
+    if (GST_VIDEO_CODEC_FRAME_IS_FORCE_KEYFRAME (gst_frame) &&
+        !(self->gop.cur_frame_index == 0 ||
+            self->gop.cur_frame_index == self->gop.idr_period)) {
+      GST_DEBUG_OBJECT (base, "system_frame_number: %d is a force key "
+          "frame(IDR), begin a new GOP.", gst_frame->system_frame_number);
 
-      g_queue_clear_full (&base->ref_list,
-          (GDestroyNotify) gst_video_codec_frame_unref);
+      frame->poc = 0;
+      frame->type = self->gop.frame_types[0].slice_type;
+      frame->is_ref = self->gop.frame_types[0].is_ref;
+      frame->pyramid_level = self->gop.frame_types[0].pyramid_level;
+      frame->left_ref_poc_diff = self->gop.frame_types[0].left_ref_poc_diff;
+      frame->right_ref_poc_diff = self->gop.frame_types[0].right_ref_poc_diff;
 
       GST_VIDEO_CODEC_FRAME_SET_SYNC_POINT (gst_frame);
+
+      /* The previous key frame should be already be poped out. */
+      g_assert (self->gop.last_keyframe == NULL);
+
+      /* An empty reorder list, start the new GOP immediately. */
+      if (g_queue_is_empty (&base->reorder_list)) {
+        self->gop.cur_frame_index = 1;
+        self->gop.cur_frame_num = 0;
+        g_queue_clear_full (&base->ref_list,
+            (GDestroyNotify) gst_video_codec_frame_unref);
+        last = FALSE;
+      } else {
+        /* Cache the key frame and end the current GOP.
+           Next time calling this push() without frame, start the new GOP. */
+        self->gop.last_keyframe = gst_frame;
+        last = TRUE;
+      }
+
+      add_cached_key_frame = TRUE;
+    } else {
+      /* Begin a new GOP, should have a empty reorder_list. */
+      if (self->gop.cur_frame_index == self->gop.idr_period) {
+        g_assert (g_queue_is_empty (&base->reorder_list));
+        self->gop.cur_frame_index = 0;
+        self->gop.cur_frame_num = 0;
+      }
+
+      frame->poc =
+          ((self->gop.cur_frame_index * 2) % self->gop.max_pic_order_cnt);
+
+      /* TODO: move most this logic onto vabaseenc class  */
+      if (self->gop.cur_frame_index == 0) {
+        g_assert (frame->poc == 0);
+        GST_LOG_OBJECT (self, "system_frame_number: %d, an IDR frame, starts"
+            " a new GOP", gst_frame->system_frame_number);
+
+        g_queue_clear_full (&base->ref_list,
+            (GDestroyNotify) gst_video_codec_frame_unref);
+
+        GST_VIDEO_CODEC_FRAME_SET_SYNC_POINT (gst_frame);
+      }
+
+      frame->type = self->gop.frame_types[self->gop.cur_frame_index].slice_type;
+      frame->is_ref = self->gop.frame_types[self->gop.cur_frame_index].is_ref;
+      frame->pyramid_level =
+          self->gop.frame_types[self->gop.cur_frame_index].pyramid_level;
+      frame->left_ref_poc_diff =
+          self->gop.frame_types[self->gop.cur_frame_index].left_ref_poc_diff;
+      frame->right_ref_poc_diff =
+          self->gop.frame_types[self->gop.cur_frame_index].right_ref_poc_diff;
+
+      GST_LOG_OBJECT (self, "Push frame, system_frame_number: %d, poc %d, "
+          "frame type %s", gst_frame->system_frame_number, frame->poc,
+          _slice_type_name (frame->type));
+
+      self->gop.cur_frame_index++;
+
+      g_queue_push_tail (&base->reorder_list,
+          gst_video_codec_frame_ref (gst_frame));
     }
-
-    frame->type = self->gop.frame_types[self->gop.cur_frame_index].slice_type;
-    frame->is_ref = self->gop.frame_types[self->gop.cur_frame_index].is_ref;
-    frame->pyramid_level =
-        self->gop.frame_types[self->gop.cur_frame_index].pyramid_level;
-    frame->left_ref_poc_diff =
-        self->gop.frame_types[self->gop.cur_frame_index].left_ref_poc_diff;
-    frame->right_ref_poc_diff =
-        self->gop.frame_types[self->gop.cur_frame_index].right_ref_poc_diff;
-
-    if (GST_VIDEO_CODEC_FRAME_IS_FORCE_KEYFRAME (gst_frame)) {
-      GST_DEBUG_OBJECT (self, "system_frame_number: %d, a force key frame,"
-          " promote its type from %s to %s", gst_frame->system_frame_number,
-          _slice_type_name (frame->type), _slice_type_name (GST_H264_I_SLICE));
-      frame->type = GST_H264_I_SLICE;
-      frame->is_ref = TRUE;
+  } else if (self->gop.last_keyframe) {
+    g_assert (self->gop.last_keyframe ==
+        g_queue_peek_tail (&base->reorder_list));
+    if (g_queue_get_length (&base->reorder_list) == 1) {
+      /* The last cached key frame begins a new GOP */
+      self->gop.cur_frame_index = 1;
+      self->gop.cur_frame_num = 0;
+      self->gop.last_keyframe = NULL;
+      g_queue_clear_full (&base->ref_list,
+          (GDestroyNotify) gst_video_codec_frame_unref);
     }
-
-    GST_LOG_OBJECT (self, "Push frame, system_frame_number: %d, poc %d, "
-        "frame type %s", gst_frame->system_frame_number, frame->poc,
-        _slice_type_name (frame->type));
-
-    self->gop.cur_frame_index++;
-    g_queue_push_tail (&base->reorder_list,
-        gst_video_codec_frame_ref (gst_frame));
   }
 
   /* ensure the last one a non-B and end the GOP. */
@@ -1786,6 +1832,12 @@ _push_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame * gst_frame,
     }
   }
 
+  /* Insert the cached next key frame after ending the current GOP. */
+  if (add_cached_key_frame) {
+    g_queue_push_tail (&base->reorder_list,
+        gst_video_codec_frame_ref (gst_frame));
+  }
+
   return TRUE;
 }
 
@@ -1807,7 +1859,7 @@ _count_backward_ref_num (gpointer data, gpointer user_data)
 }
 
 static GstVideoCodecFrame *
-_pop_pyramid_b_frame (GstVaH264Enc * self)
+_pop_pyramid_b_frame (GstVaH264Enc * self, guint gop_len)
 {
   GstVaBaseEnc *base = GST_VA_BASE_ENC (self);
   guint i;
@@ -1822,7 +1874,7 @@ _pop_pyramid_b_frame (GstVaH264Enc * self)
   b_vaframe = NULL;
 
   /* Find the lowest level with smallest poc. */
-  for (i = 0; i < g_queue_get_length (&base->reorder_list); i++) {
+  for (i = 0; i < gop_len; i++) {
     GstVaH264EncFrame *vaf;
     GstVideoCodecFrame *f;
 
@@ -1854,7 +1906,7 @@ again:
   /* Check whether its refs are already poped. */
   g_assert (b_vaframe->left_ref_poc_diff != 0);
   g_assert (b_vaframe->right_ref_poc_diff != 0);
-  for (i = 0; i < g_queue_get_length (&base->reorder_list); i++) {
+  for (i = 0; i < gop_len; i++) {
     GstVaH264EncFrame *vaf;
     GstVideoCodecFrame *f;
 
@@ -1896,6 +1948,7 @@ _pop_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame ** out_frame)
   GstVaH264Enc *self = GST_VA_H264_ENC (base);
   GstVaH264EncFrame *vaframe;
   GstVideoCodecFrame *frame;
+  guint gop_len;
   struct RefFramesCount count;
 
   g_return_val_if_fail (self->gop.cur_frame_index <= self->gop.idr_period,
@@ -1906,16 +1959,21 @@ _pop_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame ** out_frame)
   if (g_queue_is_empty (&base->reorder_list))
     return TRUE;
 
+  gop_len = g_queue_get_length (&base->reorder_list);
+
+  if (self->gop.last_keyframe && gop_len > 1)
+    gop_len--;
+
   /* Return the last pushed non-B immediately. */
-  frame = g_queue_peek_tail (&base->reorder_list);
+  frame = g_queue_peek_nth (&base->reorder_list, gop_len - 1);
   vaframe = _enc_frame (frame);
   if (vaframe->type != GST_H264_B_SLICE) {
-    frame = g_queue_pop_tail (&base->reorder_list);
+    frame = g_queue_pop_nth (&base->reorder_list, gop_len - 1);
     goto get_one;
   }
 
   if (self->gop.b_pyramid) {
-    frame = _pop_pyramid_b_frame (self);
+    frame = _pop_pyramid_b_frame (self, gop_len);
     if (frame == NULL)
       return TRUE;
     goto get_one;
@@ -3065,6 +3123,7 @@ gst_va_h264_enc_flush (GstVideoEncoder * venc)
   /* begin from an IDR after flush. */
   self->gop.cur_frame_index = 0;
   self->gop.cur_frame_num = 0;
+  self->gop.last_keyframe = NULL;
 
   return GST_VIDEO_ENCODER_CLASS (parent_class)->flush (venc);
 }

subprojects/gst-plugins-bad/sys/va/gstvah265enc.c

@@ -307,6 +307,8 @@ struct _GstVaH265Enc
 
     guint num_reorder_frames;
     guint max_dpb_size;
+
+    GstVideoCodecFrame *last_keyframe;
   } gop;
 
   struct
@@ -2028,55 +2030,96 @@ _h265_push_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame * gst_frame,
 {
   GstVaH265Enc *self = GST_VA_H265_ENC (base);
   GstVaH265EncFrame *frame;
+  gboolean add_cached_key_frame = FALSE;
 
   g_return_val_if_fail (self->gop.cur_frame_index <= self->gop.idr_period,
       FALSE);
 
   if (gst_frame) {
-    /* Begin a new GOP, should have a empty reorder_list. */
-    if (self->gop.cur_frame_index == self->gop.idr_period) {
-      g_assert (g_queue_is_empty (&base->reorder_list));
-      self->gop.cur_frame_index = 0;
-    }
-
     frame = _enc_frame (gst_frame);
-    frame->poc = self->gop.cur_frame_index;
-    g_assert (self->gop.cur_frame_index <= self->gop.max_pic_order_cnt);
 
-    if (self->gop.cur_frame_index == 0) {
-      g_assert (frame->poc == 0);
-      GST_LOG_OBJECT (self, "system_frame_number: %d, an IDR frame, starts"
-          " a new GOP", gst_frame->system_frame_number);
+    /* Force to insert the key frame inside a GOP, just end the current
+       GOP and start a new one. */
+    if (GST_VIDEO_CODEC_FRAME_IS_FORCE_KEYFRAME (gst_frame) &&
+        !(self->gop.cur_frame_index == 0 ||
+            self->gop.cur_frame_index == self->gop.idr_period)) {
+      GST_DEBUG_OBJECT (base, "system_frame_number: %d is a force key "
+          "frame(IDR), begin a new GOP.", gst_frame->system_frame_number);
 
+      frame->poc = 0;
+      frame->type = self->gop.frame_types[0].slice_type;
+      frame->is_ref = self->gop.frame_types[0].is_ref;
+      frame->pyramid_level = self->gop.frame_types[0].pyramid_level;
+      frame->left_ref_poc_diff = self->gop.frame_types[0].left_ref_poc_diff;
+      frame->right_ref_poc_diff = self->gop.frame_types[0].right_ref_poc_diff;
+
+      GST_VIDEO_CODEC_FRAME_SET_SYNC_POINT (gst_frame);
+
+      /* The previous key frame should be already be poped out. */
+      g_assert (self->gop.last_keyframe == NULL);
+
+      /* An empty reorder list, start the new GOP immediately. */
+      if (g_queue_is_empty (&base->reorder_list)) {
+        self->gop.cur_frame_index = 1;
+        g_queue_clear_full (&base->ref_list,
+            (GDestroyNotify) gst_video_codec_frame_unref);
+        last = FALSE;
+      } else {
+        /* Cache the key frame and end the current GOP.
+           Next time calling this push() without frame, start the new GOP. */
+        self->gop.last_keyframe = gst_frame;
+        last = TRUE;
+      }
+
+      add_cached_key_frame = TRUE;
+    } else {
+      /* Begin a new GOP, should have a empty reorder_list. */
+      if (self->gop.cur_frame_index == self->gop.idr_period) {
+        g_assert (g_queue_is_empty (&base->reorder_list));
+        self->gop.cur_frame_index = 0;
+      }
+
+      frame->poc = self->gop.cur_frame_index;
+      g_assert (self->gop.cur_frame_index <= self->gop.max_pic_order_cnt);
+
+      if (self->gop.cur_frame_index == 0) {
+        g_assert (frame->poc == 0);
+        GST_LOG_OBJECT (self, "system_frame_number: %d, an IDR frame, starts"
+            " a new GOP", gst_frame->system_frame_number);
+
+        g_queue_clear_full (&base->ref_list,
+            (GDestroyNotify) gst_video_codec_frame_unref);
+
+        GST_VIDEO_CODEC_FRAME_SET_SYNC_POINT (gst_frame);
+      }
+
+      frame->type = self->gop.frame_types[self->gop.cur_frame_index].slice_type;
+      frame->is_ref = self->gop.frame_types[self->gop.cur_frame_index].is_ref;
+      frame->pyramid_level =
+          self->gop.frame_types[self->gop.cur_frame_index].pyramid_level;
+      frame->left_ref_poc_diff =
+          self->gop.frame_types[self->gop.cur_frame_index].left_ref_poc_diff;
+      frame->right_ref_poc_diff =
+          self->gop.frame_types[self->gop.cur_frame_index].right_ref_poc_diff;
+
+      GST_LOG_OBJECT (self, "Push frame, system_frame_number: %d, poc %d, "
+          "frame type %s", gst_frame->system_frame_number, frame->poc,
+          _h265_slice_type_name (frame->type));
+
+      self->gop.cur_frame_index++;
+      g_queue_push_tail (&base->reorder_list,
+          gst_video_codec_frame_ref (gst_frame));
+    }
+  } else if (self->gop.last_keyframe) {
+    g_assert (self->gop.last_keyframe ==
+        g_queue_peek_tail (&base->reorder_list));
+    if (g_queue_get_length (&base->reorder_list) == 1) {
+      /* The last cached key frame begins a new GOP */
+      self->gop.cur_frame_index = 1;
+      self->gop.last_keyframe = NULL;
       g_queue_clear_full (&base->ref_list,
           (GDestroyNotify) gst_video_codec_frame_unref);
     }
-
-    frame->type = self->gop.frame_types[self->gop.cur_frame_index].slice_type;
-    frame->is_ref = self->gop.frame_types[self->gop.cur_frame_index].is_ref;
-    frame->pyramid_level =
-        self->gop.frame_types[self->gop.cur_frame_index].pyramid_level;
-    frame->left_ref_poc_diff =
-        self->gop.frame_types[self->gop.cur_frame_index].left_ref_poc_diff;
-    frame->right_ref_poc_diff =
-        self->gop.frame_types[self->gop.cur_frame_index].right_ref_poc_diff;
-
-    if (GST_VIDEO_CODEC_FRAME_IS_FORCE_KEYFRAME (gst_frame)) {
-      GST_DEBUG_OBJECT (self, "system_frame_number: %d, a force key frame,"
-          " promote its type from %s to %s", gst_frame->system_frame_number,
-          _h265_slice_type_name (frame->type),
-          _h265_slice_type_name (GST_H265_I_SLICE));
-      frame->type = GST_H265_I_SLICE;
-      frame->is_ref = TRUE;
-    }
-
-    GST_LOG_OBJECT (self, "Push frame, system_frame_number: %d, poc %d, "
-        "frame type %s", gst_frame->system_frame_number, frame->poc,
-        _h265_slice_type_name (frame->type));
-
-    self->gop.cur_frame_index++;
-    g_queue_push_tail (&base->reorder_list,
-        gst_video_codec_frame_ref (gst_frame));
   }
 
   /* ensure the last one a non-B and end the GOP. */
@@ -2096,6 +2139,12 @@ _h265_push_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame * gst_frame,
     }
   }
 
+  /* Insert the cached next key frame after ending the current GOP. */
+  if (add_cached_key_frame) {
+    g_queue_push_tail (&base->reorder_list,
+        gst_video_codec_frame_ref (gst_frame));
+  }
+
   return TRUE;
 }
 
@@ -2117,7 +2166,7 @@ _count_backward_ref_num (gpointer data, gpointer user_data)
 }
 
 static GstVideoCodecFrame *
-_h265_pop_pyramid_b_frame (GstVaH265Enc * self)
+_h265_pop_pyramid_b_frame (GstVaH265Enc * self, guint gop_len)
 {
   GstVaBaseEnc *base = GST_VA_BASE_ENC (self);
   guint i;
@@ -2132,7 +2181,7 @@ _h265_pop_pyramid_b_frame (GstVaH265Enc * self)
   b_vaframe = NULL;
 
   /* Find the highest level with smallest poc. */
-  for (i = 0; i < g_queue_get_length (&base->reorder_list); i++) {
+  for (i = 0; i < gop_len; i++) {
     GstVaH265EncFrame *vaf;
     GstVideoCodecFrame *f;
 
@@ -2164,7 +2213,7 @@ again:
   /* Check whether its refs are already poped. */
   g_assert (b_vaframe->left_ref_poc_diff != 0);
   g_assert (b_vaframe->right_ref_poc_diff != 0);
-  for (i = 0; i < g_queue_get_length (&base->reorder_list); i++) {
+  for (i = 0; i < gop_len; i++) {
     GstVaH265EncFrame *vaf;
     GstVideoCodecFrame *f;
 
@@ -2206,6 +2255,7 @@ _h265_pop_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame ** out_frame)
   GstVaH265Enc *self = GST_VA_H265_ENC (base);
   GstVaH265EncFrame *vaframe;
   GstVideoCodecFrame *frame;
+  guint gop_len;
   struct RefFramesCount count;
 
   g_return_val_if_fail (self->gop.cur_frame_index <= self->gop.idr_period,
@@ -2216,16 +2266,21 @@ _h265_pop_one_frame (GstVaBaseEnc * base, GstVideoCodecFrame ** out_frame)
   if (g_queue_is_empty (&base->reorder_list))
     return TRUE;
 
+  gop_len = g_queue_get_length (&base->reorder_list);
+
+  if (self->gop.last_keyframe && gop_len > 1)
+    gop_len--;
+
   /* Return the last pushed non-B immediately. */
-  frame = g_queue_peek_tail (&base->reorder_list);
+  frame = g_queue_peek_nth (&base->reorder_list, gop_len - 1);
   vaframe = _enc_frame (frame);
   if (vaframe->type != GST_H265_B_SLICE) {
-    frame = g_queue_pop_tail (&base->reorder_list);
+    frame = g_queue_pop_nth (&base->reorder_list, gop_len - 1);
     goto get_one;
   }
 
   if (self->gop.b_pyramid) {
-    frame = _h265_pop_pyramid_b_frame (self);
+    frame = _h265_pop_pyramid_b_frame (self, gop_len);
     if (frame == NULL)
       return TRUE;
 
@@ -2529,6 +2584,7 @@ gst_va_h265_enc_reset_state (GstVaBaseEnc * base)
   self->gop.backward_ref_num = 0;
   self->gop.num_reorder_frames = 0;
   self->gop.max_dpb_size = 0;
+  self->gop.last_keyframe = NULL;
 
   self->rc.max_bitrate = 0;
   self->rc.target_bitrate = 0;
@@ -4657,6 +4713,7 @@ gst_va_h265_enc_flush (GstVideoEncoder * venc)
 
   /* begin from an IDR after flush. */
   self->gop.cur_frame_index = 0;
+  self->gop.last_keyframe = NULL;
 
   return GST_VIDEO_ENCODER_CLASS (parent_class)->flush (venc);
 }

subprojects/gst-plugins-bad/tests/examples/va/vaenc-dynamic-reconfigure.c

@@ -43,6 +43,8 @@ typedef struct
 
   gint prev_width;
   gint prev_height;
+
+  guint force_keyframe_count;
 } TestCallbackData;
 
 static gboolean
@@ -130,9 +132,10 @@ loop_rate_control (GstElement * encoder)
   g_object_set (encoder, "rate-control", enum_class->values[i].value, NULL);
 }
 
+static gboolean force_key_frame;
+
 static GstPadProbeReturn
-resolution_change_probe (GstPad * pad, GstPadProbeInfo * info,
-    gpointer user_data)
+pad_buffer_probe (GstPad * pad, GstPadProbeInfo * info, gpointer user_data)
 {
   GstPadProbeReturn ret = GST_PAD_PROBE_OK;
   TestCallbackData *data = (TestCallbackData *) user_data;
@@ -144,6 +147,17 @@ resolution_change_probe (GstPad * pad, GstPadProbeInfo * info,
     GstPad *peer = gst_pad_get_peer (pad);
     GstFlowReturn flow_ret = GST_FLOW_OK;
 
+    if (force_key_frame) {
+      GstEvent *force_key_event;
+
+      force_key_frame = FALSE;
+
+      force_key_event = gst_video_event_new_downstream_force_key_unit
+          (GST_BUFFER_PTS (buffer), GST_CLOCK_TIME_NONE,
+          GST_CLOCK_TIME_NONE, FALSE, data->force_keyframe_count++);
+      gst_pad_push_event (pad, force_key_event);
+    }
+
     ret = GST_PAD_PROBE_HANDLED;
 
     if (peer) {
@@ -208,6 +222,7 @@ print_keyboard_help (void)
     "p", "Decrease QP-P (only in CQP)"}, {
     "B", "Increase QP-B (only in CQP)"}, {
     "b", "Decrease QP-B (only in CQP)"}, {
+    "f", "Force to set a key frame"}, {
     "k", "show keyboard shortcuts"}
   };
   /* *INDENT-ON* */
@@ -418,6 +433,10 @@ keyboard_cb (gchar input, gboolean is_ascii, gpointer user_data)
           g_object_set (data->encoder, "qpb", qpb, NULL);
         break;
       }
+      case 'f':{
+        force_key_frame = TRUE;
+        break;
+      }
       default:
         break;
     }
@@ -541,7 +560,7 @@ main (gint argc, gchar ** argv)
 
   pad = gst_element_get_static_pad (capsfilter, "src");
   data.probe_id = gst_pad_add_probe (pad, GST_PAD_PROBE_TYPE_BUFFER,
-      resolution_change_probe, &data, NULL);
+      pad_buffer_probe, &data, NULL);
   gst_object_unref (pad);
   data.prev_width = width;
   data.prev_height = height;

subprojects/gst-python/meson.build

@@ -45,35 +45,53 @@ pylib_loc = get_option('libpython-dir')
 fsmod = import('fs')
 pylib_prefix = 'lib'
 pylib_suffix = 'so'
+pylib_ver = python_dep.version()
+pylib_locs = []
 if host_system == 'windows'
   if cc.get_argument_syntax() == 'msvc'
     pylib_prefix = ''
   endif
   pylib_suffix = 'dll'
+  pylib_ver = pylib_ver.replace('.', '')
 elif host_system == 'darwin'
   pylib_suffix = 'dylib'
 endif
 pylib_fnames = []
 # Library name with soversion, non-devel package
-pylib_fnames += python.get_variable('INSTSONAME', [])
+if python.has_variable('INSTSONAME')
+  # For example, libpython3.12.so.1.0 (Linux), libpython3.11.dll.a (MSYS2), etc.
+  pylib_fnames += python.get_variable('INSTSONAME')
+endif
 # Library name without soversion, devel package, framework, etc.
-pylib_fnames += python.get_variable('LDLIBRARY', [])
+if python.has_variable('LDLIBRARY')
+  # For example, libpython3.12.so (Linux), libpython3.11.dll.a (MSYS2), etc.
+  pylib_fnames += python.get_variable('LDLIBRARY')
+endif
 # Manually construct name as a fallback
 pylib_fnames += [
-  pylib_prefix + 'python' + python_dep.version() + python_abi_flags + '.' + pylib_suffix
+  pylib_prefix + 'python' + pylib_ver + python_abi_flags + '.' + pylib_suffix
 ]
 if pylib_loc != ''
   pylib_locs = [pylib_loc]
 else
-  pylib_locs = [
-    python.get_variable('LIBDIR', ''),
-    python.get_variable('LIBPL', ''),
-  ]
+  if python.has_variable('LIBDIR')
+    pylib_locs += python.get_variable('LIBDIR')
+  endif
+  if python.has_variable('LIBPL')
+    pylib_locs += python.get_variable('LIBPL')
+  endif
+  # On Windows, python312.dll is in the rootdir where Python is installed,
+  # which is configured as the "prefix" in sysconfig.
+  if host_system == 'windows'
+    pylib_locs += python.get_variable('prefix')
+  endif
 endif
 pylib_fname = ''
 foreach loc: pylib_locs
   foreach fname: pylib_fnames
-    if fsmod.exists(loc / fname)
+    fpath = loc / fname
+    debug(f'Looking for Python library at: @fpath@')
+    if fsmod.exists(fpath)
       pylib_fname = fname
       message(f'PY_LIB_FNAME = @fname@ (@loc@)')
       break
@@ -81,12 +99,7 @@ foreach loc: pylib_locs
   endforeach
 endforeach
 if pylib_fname == ''
-  error_msg = 'Could not find python library to load'
-  if python_opt.enabled()
-    error(error_msg)
-  else
-    message(error_msg)
-  endif
+  message('Could not find python library to load, will try loading at runtime')
 endif
 
 pygi_override_dir = get_option('pygi-overrides-dir')